VNU-UET Repository: No conditions. Results ordered -Date Deposited. 2024-03-28T21:55:06ZEPrintshttp://eprints.uet.vnu.edu.vn/images/sitelogo.pnghttps://eprints.uet.vnu.edu.vn/eprints/2022-10-26T21:59:46Z2022-10-26T21:59:46Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4164This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/41642022-10-26T21:59:46ZFormation and Study of Nanostructured M-Monolayers and LS-Films of TriphenylcorroleThao T. VuLarissa A. MaiorovaDmitrii B. BerezinOskar I. Koifman2020-12-13T15:49:19Z2022-10-26T21:59:50Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4163This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/41632020-12-13T15:49:19ZThermal stability of meso-substituted metal corroles in inert and oxidative mediaVu Thi ThaoD. R. KarimovS. S. GuseinovE. V. BalantsevaD. B. Berezin2019-12-10T15:58:17Z2019-12-10T15:58:17Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/3814This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/38142019-12-10T15:58:17ZA bigraph representation model and directional search mechanism for debatesThe beauty of thinking resides not only in finding answers but also in challenging already existing ones and creating intelligible networks of thoughts and ideas of many different perspectives. Understanding that the essence of critical thinking presents in the flows of questions and answers and aiming at a tool of augmenting it, we propose a new knowledge representation model based on bipartite graphs and a set of functions aided to explore those graphs. A bipartite graph has two disjoint vertex sets that are question and answer sets. Every edge connects a question to an answer holds an evidence for the answer and every edge connects an answer to a question holds an argument raised from the answer. The directional search mechanism is particularly designed to reuse reasoning flows in the debate graphs by a projecting function between the question and answer sets. We also introduce a framework placing the model and the search mechanism altogether in collaborative applications. Many philosophical debates are collected to demonstrate the advantages of the bigraph model besides its simplicity. The analysis and experiments on optimizing semantic search show a sufficient performance for a real-time application.Diep Thi Ngoc Nguyenngocdiep@vnu.edu.vnYasushi Kiyoki2019-12-05T13:58:54Z2019-12-05T13:58:54Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/3710This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/37102019-12-05T13:58:54ZModeling sequential preferences with dynamic user and context factorsUsers express their preferences for items in diverse forms,
through their liking for items, as well as through the sequence in which they consume items. The latter, referred to as “sequential preference”, manifests itself in scenarios such as song or video playlists, topics one reads or writes about in social media, etc. The current approach to modeling sequential preferences relies primarily on the sequence information, i.e., which item follows another item. However, there are other important factors, due to either the user or the context, which may dynamically a↵ect the way a sequence unfolds. In this work, we develop generative modeling of sequences, incorporating dynamic user-biased emission and context-biased transition for sequential preference. Experiments on publicly-available real-life datasets as well as synthetic data show significant improvements in accuracy at predicting the next item in a sequence.Duc-Trong Letrongld@vnu.edu.vnHady W. Lauwhadywlauw@smu.edu.sgYuan Fangyfang@smu.edu.sg2018-12-08T08:23:31Z2018-12-08T08:23:31Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/3193This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/31932018-12-08T08:23:31ZOn the Use of Surplus Division to Facilitate Efficient Negotiation in the Presence of Incomplete InformationQuoc Bao VoTrong Hieu Tranhieutt@vnu.edu.vnThi Hong Khanh Nguyen2018-11-15T09:20:10Z2018-11-15T09:20:10Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/3145This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/31452018-11-15T09:20:10ZTrue nature of active layers in organic solar cells fabricated by sequential casting of donor and acceptor layersThe operation characteristics of nominal bilayer (BL) organic solar cells (OSCs), the active layers (ALs) of which consisted of sequentially casted bottom P3HT donor and top ICBA acceptor layers, resembled those of OSCs with bulk heterojunction (BHJ) ALs. Optical analysis and device simulations showed that such resemblance can be attributed to a similarity in the micromorphology of ALs; as‐deposited BL‐type ALs transformed spontaneously into BHJ‐type ALs. The inclusion of P3HT nanowires (NWs) in the donor layers resulted in different AL micromorphology and consequently a larger power conversion efficiency. Separate assessment of the exciton generation and charge–carrier transport and/or extraction showed that the contribution of P3HT NWs was more prominent in optical effects.Jong Hyuk YimSung‐yoon JoeDuc Cuong Nguyencuongnd@vnu.edu.vnShin Young RyuNa Young HaY. H. AhnJi‐Yong ParkSoonil Leesoonil@ajou.ac.kr2018-11-15T09:20:01Z2018-11-15T09:20:01Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/3144This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/31442018-11-15T09:20:01ZHole‐extraction layer dependence of defect formation and operation of planar CH3NH3PbI3 perovskite solar cellsThree planar CH3NH3PbI3 (MAPbI3) solar cells having the same structure except a hole‐extraction layer (HEL) showed distinctive difference in operation characteristics. Analysis of frequency‐dependent capacitance and dielectric‐loss spectra of the three MAPbI3 devices showed two types of recombination‐loss channels with different time constants that we attributed respectively to interface and bulk defects. Discrepancy in defect formation among the three devices with a HEL of PEDOT:PSS, NiOx, or Cu‐doped NiOx was not surprising because grain‐size distribution and crystalline quality of MAPbI3 can be affected by surface energy and morphology of underlying HELs. We were able to quantify interface and bulk defects in these MAPbI3solar cells based on systematic and simultaneous simulations of capacitance and dielectric‐loss spectra, and current–voltage characteristics by using the device simulator SCAPS.Duc Cuong Nguyencuongnd@vnu.edu.vnSung‐yoon JoeNa Young HaHui Joon ParkJi‐Yong ParkY. H. AhnSoonil Leesoonil@ajou.ac.kr2018-11-15T09:19:47Z2018-11-15T09:19:47Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/3019This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/30192018-11-15T09:19:47ZSolution-Processible Crystalline NiO Nanoparticles for High-Performance Planar Perovskite Photovoltaic CellsIn this work, we report on solution-based p-i-n-type planar-structured CH3NH3PbI3 perovskite
photovoltaic (PV) cells, in which pre-crystallized NiO nanoparticles (NPs) without post-treatment are
used to form a hole transport layer (HTL). X-ray diffraction and high-resolution transmission electron
microscopy showed the crystallinity of the NPs, and atomic force microscopy and scanning electron
microscopy confirmed the uniform surfaces of the resultant NiO thin film and the subsequent perovskite
photoactive layer. Compared to the conventional poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) HTL, the NiO HTL had excellent energy-level alignment with that of CH3NH3PbI3
and improved electron-blocking capability, as analyzed by photoelectron spectroscopy and diode
modeling, resulting in Voc ~0.13 V higher than conventional PEDOT:PSS-based devices. Consequently, a
power conversion efficiency (PCE) of 15.4% with a high fill factor (FF, 0.74), short-circuit current density
(Jsc, 20.2 mA·cm−2), and open circuit voltage (Voc, 1.04 V) having negligible hysteresis and superior air
stability has been achieved.Uisik KwonBong-Gi KimDuc Cuong Nguyencuongnd@vnu.edu.vnJong-Hyeon ParkNa Young HaSeung-Joo KimSeung Hwan KoSoonil Leesoonil@ajou.ac.krDaeho Leedhl@gachon.ac.krHui Joon Parkhuijoon@ajou.ac.kr2018-10-09T09:58:45Z2018-10-09T09:58:45Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/3089This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/30892018-10-09T09:58:45ZFabrication of Ferrite-Based Integrated Micro-Inductors onto Silicon WaferIn this work, the technology for fabricating integrated micro-inductors onto silicon is
developed. The paper will report the experimental process and technology development to
fabricate the micro-inductor on-to silicon substrates with the hybrid integration approach.
Copper is used for the fabrication of the conductor windings and vias. Electro-deposition is
chosen for depositing copper. Via is electro-deposited to make the connection between bottom
tracks and top tracks. The ferrite core is fabricated and sintered from in-house ferrites or
commercial ferrite films.Yen Mai Nguyenmainty85@gmail.comMagali Brunet2018-01-18T02:21:03Z2018-01-18T02:21:03Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2835This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/28352018-01-18T02:21:03ZNanocomposite materials for energy conversion and storageDinh Duc Nguyenducnd@vnu.edu.vn2017-12-14T03:34:58Z2017-12-14T03:34:58Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2777This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/27772017-12-14T03:34:58ZOptimizing GLCNMO version 2 method to detect Vietnam's urban expansionNo global scale land cover classification method performs with high accuracy at local scale. This study tries to develop a classification algorithm for urban area in Vietnam. This is the first assessment of the Global Land Cover by National Mapping Organizations (GLCNMO) version 2 method for producing global urban map in 2008. An improved and optimized algorithm is then developed based on the GLCNMO method for Vietnam taking into account of local natural and social conditions. Improving method is then applied to produce urban maps of Vietnam for the years of 2008 and 2015. Accuracy assessment showed that the improved method can achieve up to 13% higher precision and 10% higher F1 measure as compared to the global GNCNMO method. Also, an increasing trend was observed in population density in urban area in the period from 2008 to 2015 in Vietnam which may correspond to fast urbanization process in the country. The cities also tend to become less green in 2015 than 2008 as indicated by comparing the Normalized Difference Vegetation Index (NDVI) between the two years.Tuan Dung Phamdungpt@fimo.edu.vnDuc Chuc Manchucmd@fimo.edu.vnThi Nhat Thanh Nguyenthanhntn@vnu.edu.vnQuang Hung Buihungbq@vnu.edu.vnMinh Chung Doan2017-12-14T03:34:49Z2017-12-14T03:34:49Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2776This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/27762017-12-14T03:34:49ZStandardization procedure for automatic environmental data: A case study in Hanoi, VietnamIn Vietnam, environmental data collected from ground-based stations may contain abnormal or missing values due to several problems during operation, i.e. sensor's problems. This paper proposes a standardization procedure which try to detect unusual values and fill in missing data. Experiments were conducted for PM10 data. Two datasets measured in 01/2011 and 01/2012 at Nguyen Van Cu station in Hanoi, Vietnam is used for experiments. For the abnormal detection process, unusual data can be informed to the data analyzers at ground stations for judging. For the missing filling process, the first dataset is used as training dataset to construct regression models for predicting missing data, the second dataset is used as testing data. In the worst case, suppose 100% PM10 is missing, Root Mean Square Error (RMSE) and Mean Absolute Percentage Error (MAPE) are 51 µg/m3 and 45% respectively. Correlation coefficient (R) between original PM10 data and predicted PM10 data is 0.56. In addition, different scenarios taking account of percentage of missing data of the whole testing dataset are also considered. Experimental results showed that it is best to perform missing filling process on datasets that contain 10% to 30% of missing data. For this case, RMSE ranges from 15–25 µg/m3 and MAPE varies from 5 to 13%.Duc Linh NguyenDuc Chuc Manchucmd@fimo.edu.vnQuang Hung Buihungbq@vnu.edu.vnThi Nhat Thanh Nguyenthanhntn@vnu.edu.vn2017-11-23T07:07:48Z2017-11-23T07:07:48Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2340This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23402017-11-23T07:07:48ZString Distance For Automatic Image ClassificationHong Thinh Nguyenhongthinh.nguyen@vnu.edu.vnVu Ha Lehalv@vnu.edu.vnBarat Cecilececile.barat@univ-st-etienne.frDucottet Christophechristophe.ducottet@univ-st-etienne.fr2017-11-16T04:33:06Z2017-11-16T04:33:06Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2661This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/26612017-11-16T04:33:06ZPOLYESTER KNIT-FABRICS TREATED WITH CATIONIC DIRECT DYES USING PLASMA -INDUCED GRAFT-POLYMERIZATIONPolyester knit-fabrics were treated by argon-helium plasma at room temperature and ambient pressure, subsequently graft-polymerized with acrylic acid in vapor. Plasma interaction to the polyester fibres and graft-polymerization of carboxyl functional groups were investigated. Finally, the polyester knit-fabric grafted with carboxyl groups were treated with cationic direct dyes at around 800C and ambient pressure. Results obtained show that grafted surface of the knit fabrics was dyed with the red color, and then their color surface becomes dark pink while their untreated surface has pinkish white. The graft polymerization of the carboxyl groups and the absorption of cationic direct dyes will be discussed in details.
Keywords: plasma-induced graft-polymerization, polyester-fiber knit-fabrics, cationic direct dyes, polyesterKien Cuong Nguyencuongnk@vnu.edu.vnSeiichi Kataoka2017-11-16T04:26:31Z2017-11-16T04:26:31Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2633This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/26332017-11-16T04:26:31ZSTUDY ON ITO THIN FILMS PREPARED BY
MULTI-ANNEALING TECHNIQUEIndium tin oxide (ITO) thin films have been successfully prepared by a solution process
followed by a multi-annealing method. In this study, we focus on the use of multi-annealing
method, for which each layer was annealed at a suitable temperature, instead of a conventional
annealing way, by means of a rapid thermal annealing system, in order to improve the film
quality. The crystalline structure and surface morphology of the ITO thin films were investigated
by using X-ray diffraction (XRD) spectrometer, atomic force microscope (AFM) and scanning
electron microscope (SEM). It has been obtained that all of ITO films exhibit a single phase with
(200)- and (444)-preferred orientations. The AFM and SEM observations show that the particle
size of ITO films was about 10 nm and the ITO film thickness was 180 nm, respectively. In
sequence, the electrical properties of ITO thin films were evaluated by using four-point probe
and Hall effect measurement methods, and the optical properties were investigated by UV/VIS
spectrometer. The achievement results show that the optimum ITO films possessed electrical
resistivity of 2.6 × 10-3 Ωcm and transparency higher than 90%, which strongly supports to the
application of electrode in solar cell, LED or transistor devices from viewpoints of low-cost
production and low-energy consumption.Quang Hoa NguyenThi Xuyen NguyenQuoc Viet VuongThi Huyen Trang VuHa HoangThi Thanh Tam HoangThi Dung VuVan Dung TranNguyen Quoc Trinh Buitrinhbnq@vnu.edu.vn2017-11-16T04:26:10Z2017-11-16T04:26:10Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2632This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/26322017-11-16T04:26:10ZINVESTIGATION ON STRUCTURAL AND FERROELECTRIC PROPERTIES OF Bi3.25La0.75Ti3O12 THIN FILMSLanthanum doped bismuth titanate (Bi3.25La0.75Ti3O12 abbreviated as BLT) has been known
as one of typical materials for Bi-layered perovskite structure which possess several unique
properties such as good fatigue with metal electrode and stable remanent polarization, hence it
has potential applications in ferroelectric random access memory. In this work, the BLT thin
films were fabricated on Pt/TiO2/SiO2/Si substrates by using a solution process, and then their
features including crystal structure, surface morphology, and electrical properties were
characterized by using X-ray diffraction system (XRD), scanning electron microscopy (SEM),
and electrical measurement system (Radiant Precision LC 10), respectively. The obtained results
point out that the BLT thin film annealed at 725oC is mostly optimum from a viewpoint of film
quality and ferroelectricity. In particular, the optimum BLT thin film having a thickness of 200
nm does not contain any cracks on the sample surface, and the grain size is closed to 400 nm from
SEM observation. XRD patterns imply that the BLT thin film had stoichiometric structure with
preferred orientations of (117) and (006), when annealed at temperatures higher than 725oC. In
addition, we found the influence of La (0.75) dopping on c-axis-oriented growth of BLT thin
films is clear from the structural analysis. The remanent polarization of optimum BLT thin film is
approximately 10 µC/cm2, but the ferroelectric hysteresis loops are not saturated at low applied
voltages.Van Dung TranHa HoangThi Thanh Tam HoangThi Dung VuVan Dung NguyenHong Minh DoThi Huyen Trang VuQuang Hoa NguyenNguyen Quoc Trinh Buitrinhbnq@vnu.edu.vn2017-11-16T02:41:03Z2017-11-16T02:41:03Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2637This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/26372017-11-16T02:41:03ZPhotoluminescence and I -V Characteristics of
Blended Conjugated Polymers/ZnO NanoparticlesAbstract: The investigation of photoluminescence and current-voltage (I-V) characteristics of the
MEH-PPV/PVK blended polymers doped with ZnO nanoparticles (ZnO NPs). First, PVK polymers were mixed with MEH-PPV in respect to the mass-ratio of 100:15, respectively. And
then the MEH-PPV/PVK composites were doped with ZnO NPs with the mass-ratio of 10 wt%, 15 wt% and 20 wt% of total weight blended polymers. Polymer light-emitting diodes (PLEDs), based on a hybrid composite, having structure of ITO/ MEH-PPV/PVK/ZnO/Al were made by spincoated,and subsequently vacuum-thermally evaporated.
UV-Vis absorption, photoluminescence properties, SEM micrographs of the hybrid compositelayer as well as I -V characteristics of the PLED based on the MEH-PPV/ZnO-and PVK/ZnOheterojunction were investigated. Results obtained show that the turn-on voltage of the polymers/ZnO-based PLED is lower than that of the polymers-based PLED without doped ZnO NPs. This is due to the Auger-assisted energy up-conversion process occurring at the polymers/ZnO-heterojunction that could enhance the luminescence efficiency of the PLED.
Keywords: PLED, photoluminescence efficiency, MEH-PPV, PVK, SEM, spin coating, thermal
vacuum evaporationKien Cuong Nguyencuongnk@vnu.edu.vn2017-11-09T03:21:27Z2017-11-09T03:21:27Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2624This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/26242017-11-09T03:21:27ZLow-temperature PZT thin-film ferroelectric memories fabricated on SiO2/Si and glass substratesIn a ferroelectric-gate thin film transistor memory (FGT) type structure, the gate-insulator layer is
extremely important for inducing the charge when accumulating or depleting. We concentrated on the
application of low-temperature PZT films crystallized at 450, 500 and 550 �C, instead of at conventional
high temperatures (�600 �C). Investigation of the crystalline structure and electrical properties indicated
that the PZT film, crystallized at 500 �C, was suitable for FGT fabrication because of a high (111) orientation,
large remnant polarization of 38 mC/cm2 on SiO2/Si substrate and 17.8 mC/cm2 on glass, and low
leakage current of 10�6 A/cm2. In sequence, we successfully fabricated FGT with all processes below
500 �C on a glass substrate, whose operation exhibits a memory window of 4 V, ON/OFF current ratio of
105, field-effect mobility of 0.092 cm2 V�1 s�1, and retention time of 1 h.Hong Minh DoVan Loi NguyenHuu Duc Nguyenducnh@vnu.edu.vnNguyen Quoc Trinh Buitrinhbnq@vnu.edu.vn2017-11-04T23:59:44Z2017-11-04T23:59:44Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2612This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/26122017-11-04T23:59:44ZLight source detection using multirobot systems with particle swarm optimization approachExploration and searching in unknown or hazardous environments using Multirobot
System (MRS) is among the principal topics in robotics. There have been numerous
researches on searching and detection of odor, fire or pollution sources. In this paper, we
present results on detecting light sources with MRS using modified Particle Swarm
Optimization (PSO). The robot swarm makes use of Artificial Potential Field (APF) to avoid
collision with obstacles or other robots while heading towards areas of highest ...Anh Quy Hoangquyha@vnu.edu.vnMinh Trien Phamtrienpm@vnu.edu.vn2017-10-23T08:45:53Z2017-10-23T08:45:53Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2577This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/25772017-10-23T08:45:53ZHow Reliable Are Ligand-Centric Methods for Target Fishing?Computational methods for Target Fishing (TF), also known as Target Prediction or Polypharmacology Prediction, can be used to discover new targets for small-molecule drugs. This may result in repositioning the drug in a new indication or improving our current understanding of its efficacy and side effects. While there is a substantial body of research on TF methods, there is still a need to improve their validation, which is often limited to a small part of the available targets and not easily interpretable by the user. Here we discuss how target-centric TF methods are inherently limited by the number of targets that can possibly predict (this number is by construction much larger in ligand-centric techniques). We also propose a new benchmark to validate TF methods, which is particularly suited to analyse how predictive performance varies with the query molecule. On average over approved drugs, we estimate that only five predicted targets will have to be tested to find two true targets with submicromolar potency (a strong variability in performance is however observed). In addition, we find that an approved drug has currently an average of eight known targets, which reinforces the notion that polypharmacology is a common and strong event. Furthermore, with the assistance of a control group of randomly-selected molecules, we show that the targets of approved drugs are generally harder to predict.Antonio PeonCao Cuong DangPedro Ballester2017-06-26T10:37:31Z2017-06-26T10:38:32Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2537This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/25372017-06-26T10:37:31ZBisimilarity for paraconsistent description logicsWe introduce comparisons with respect to information between interpretations in paraconsistent description logics and use them to define bisimilarity for such logics. As bisimilarity is a natural notion for characterizing indiscernibility in modal and description logics, it is useful for concept learning in description logics also when inconsistencies occur. We give preservation results and the Hennessy-Milner property for comparisons with respect to information in paraconsistent description logics. As consequences, we also obtain invariance results and the Hennessy-Milner property for bisimilarity in paraconsistent description logics.Linh Anh NguyenThi Hong Khanh NguyenNgoc Thanh NguyenQuang Thuy Hathuyhq@vnu.edu.vn2017-06-17T04:53:15Z2017-06-17T04:53:15Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2388This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23882017-06-17T04:53:15ZEffect of the Interruption of the Propagation Path on the Response of Surface Acoustic Wave TransducersThu Hang Buihangbt@vnu.edu.vnAn TranBruno MoranaJia WeiDuc Trinh Chutrinhcd@vnu.edu.vnPasqualina M. Sarro2017-06-16T03:35:48Z2017-06-16T03:35:48Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2521This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/25212017-06-16T03:35:48ZSocial-spam profile detection based on content classification and user behaviorWeb-based social system enables new community-based opportunities for participants to engage, share and interact. The rapid growth of Facebook has triggered a dramatic increase in spam volume and sophistication. Spammers post their status or comment in Page to send spam content to their friends or other users in the network. In this paper, we consider the problem of detecting spam accounts on Facebook based on comment content and user social behavior. We will propose a hybrid approach using Maximum Entropy (Maxent) model for classifying user comments as either spam or non-spam. We carefully conducted an empirical evaluation for our model on a large collection of comments in Vietnamese Facebook Pages and achieved promising results with an average accuracy of more than 90%.Thi Hong Vuonghongvt_57@vnu.edu.vnVan Hien TranMinh Duc Nguyenduchell.uet.vnu@gmail.comThi Cam Van NguyenThanh Huyen PhamMai Vu Tranvutm@vnu.edu.vn2017-06-14T09:57:38Z2017-06-14T09:57:38Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2390This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23902017-06-14T09:57:38ZAutomatic Interpretation of Unordered Point Cloud Data for UAV Navigation in ConstructionThe objective of this work is to develop a data processing system that can automatically generate waypoints for navigation of an unmanned aerial vehicle (UAV) to inspect surfaces of structures like buildings and bridges. The input includes data recorded by two 2D laser scanners, orthogonally mounted on the UAV, and an inertial measurement unit (IMU). To achieve the goal, algorithms are developed to process the data collected. They are separated into three major groups: (i) the data registration and filtering to generate a 3D model of the structure and control the density of point clouds for data completeness enhancement; (ii) the surface and obstacle detection to assist the UAV in monitoring tasks; and (iii) the waypoint generation to set the flight path. Experiments on different data sets show that the developed system is able to reconstruct a 3D point cloud of the structure, extract its surfaces and objects, and generate waypoints for the UAV to accomplish inspection tasks.Manh Duong Phungduongpm@vnu.edu.vnCong Hoang Quachhoangqc@vnu.edu.vnDuc Trinh Chutrinhcd@vnu.edu.vnNgoc Que Nguyenquenn@gmail.comTran Hiep Dinhtranhiep.dinh@vnu.edu.vnQuang Haquangha@gmail.com2017-06-14T08:28:51Z2017-06-14T08:28:51Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2505This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/25052017-06-14T08:28:51ZPhương thức quản lý truyền thông trong các hệ thống điều khiển và giám sát tập trungTrong các hệ thống điều khiển giám sát và thu thập dữ liệu (SCADA), bài toán quản lý truyền thông phải đối mặt với những thách thức về sự đa dạng trong sự truyền thông dữ liệu giữa các thiết bị công nghiệp. Chẳng hạn, từ việc hỗ trợ kết nối tới các RTU (Remote Terminal Unit) theo chuẩn truyền thông công nghiệp Modbus TCP/IP, OPC, … đến việc hỗ trợ các chuẩn mới như OPC-UA, Industrial IoT, … Ngoài ra, với sự đa dạng và phức tạp trong các nhà máy sản xuất công nghiệp, cũng cần phải có sự linh hoạt trong việc hỗ trợ các mô hình kết nối khác nhau, chẳng hạn như MultiClient, MultiServer, Redundancy. Từ thực trạng đó, nhóm nghiên cứu đã tiến hành khảo sát, đánh giá và đề xuất mô hình kiến trúc phân tầng và sử dụng chuẩn OPC-UA cho việc trao đổi dữ liệu trong các hệ thống thu thập và giám sát dữ liệu để phù hợp với yêu cầu trên. Mô hình này đã cho phép nâng cao khả năng quản lý truyền thông, cho phép mở rộng kết nối chỉ liên quan tới mở rộng giao diện tầng dưới mà không làm thay đổi cấu trúc các tầng phía trên. Thực nghiệm chúng tôi tiến hành trong khuôn khổ đề tài KC.03.26/11-15 đã cho phép minh chứng và khẳng định tính linh hoạt và hiệu quả của phương thức quản lý truyền thông đó của chúng tôi.Chi Cong Phamphamchicong@gmail.comHai Thai Trinhtrinhhaithai@gmail.comNgoc Hoa Nguyenhoa.nguyen@vnu.edu.vn2017-06-10T11:32:27Z2017-06-10T11:32:27Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2472This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24722017-06-10T11:32:27ZSieve-based coreference resolution enhances semi-supervised learning model for chemical-induced disease relation extractionThe BioCreative V chemical-disease relation (CDR) track was proposed to accelerate progress of text mining in facilitating integrative understanding ofchemical substances, diseases and their relations. In this article, we describe an extension of the UET-CAM system for mining chemical-disease relations from text data, of which performance was ranked 4th among 18 participating corresponding systems by the BioCreative CDR track committee. In Disease Named Entity Recognition and Normalization (DNER) phase, our system employs joint learning with a perceptron-based named entity recognizer (NER) and a back-off model with Semantic Supervised Indexing (SSI) and Skip-gram for named entity normalization (NEN). Crucially, for solving the chemical-induced disease (CID) sub-task, we propose a pipeline that includes a coreference resolution module and a SVM intra-sentence relations extraction model. The former module utilizes a multi-pass sieve to identify inter-sentence references for entities while the latter is trained on both the CDR data and our silverCID corpus with a rich feature set. SilverCID is the silver standard corpus contains more than 50 thousands sentences which are automatically built based on the CTD database in order to provide evidence for the CID relation extraction. We critically evaluated our method on the CDR test set in order to clarify the contribution of our system components. Results show an F1 of 82.44 for the DNER task, and a best performance of F1 58.90 on the CID task. The comparisons also demonstrate the significant contribution of the multi-pass sieve coreference resolution method and the silverCID corpus.Hoang Quynh Lelhquynh@gmail.comMai Vu Tranvutm@vnu.edu.vnThanh Hai Danghai.dang@vnu.edu.vnQuang Thuy Hathuyhq@vnu.edu.vnNigel Collier2017-06-10T11:28:30Z2017-06-10T11:28:30Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2469This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24692017-06-10T11:28:30ZPolymer dẫn và điôt phát quang hữu cơTrong gần 15 năm lại đây nhóm chúng tôi đã tiến hành các nghiên cứu khoa học về vật liệu và linh kiện trên cơ sở polymer dẫn và tổ hợp nanô polymer với ôxit kim loại. Các loại linh kiện được tập thể khoa học tập trung nghiên cứu và triển khai ứng dụng là OLED, pin mặt trời hữu cơ (OSC) và sensor màng mỏng hữu cơ (OTFS). Nhằm phần nào đáp ứng nhu cầu người đọc về vật liệu polymer và linh kiện vi điện tử hữu cơ đầy triển vọng ứng dụng này, tác giả tập trung biên soạn sách chuyên khảo “Polymer dẫn và điôt phát quang hữu cơ”. Sách được biên soạn một cách chọn lọc, cập nhật phân tích các công trình khoa học của nhiều tác giả trên thế giới và một phần đáng kể từ các công trình khoa học, luận án tiến sĩ của các thành viên trong Nhóm. Sách này có thể làm tài liệu học tập, tra cứu, tham khảo trong lĩnh vực chuyên sâu về polymer dẫn và OLED.
Sách gồm Phần mở đầu, 5 chương và Kết luận. Các chương là:
CHƯƠNG I. POLYMER DẪN ĐIỆN VÀ LINH KIỆN PHÁT QUANG HỮU CƠ
CHƯƠNG 2. CÁC KĨ THUẬT SỬ DỤNG TRONG CÔNG NGHỆ CHẾ TẠO VÀ ĐẶC TRƯNG TÍNH CHẤT VẬT LIỆU VÀ LINH KIỆN OLED
CHƯƠNG 3. TÍNH CHẤT CỦA VẬT LIỆU VÀ LINH KIỆN OLED THUẦN KHIẾT POLYMER
CHƯƠNG 4. VẬT LIỆU TỔ HỢP CẤU TRÚC NANÔ KHỐI VÀ LINH KIỆN OLED
CHƯƠNG 5. VẬT LIỆU VÀ LINH KIỆN OLED PHÁT XẠ NGƯỢCNang Dinh Nguyendinhnn@vnu.edu.vn2017-03-10T03:34:42Z2017-03-10T03:34:42Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2439This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24392017-03-10T03:34:42ZStudy of determination adjusted ratio for calculating strength of orthotropic laminated composite plates used in building shipVan Thu PhamVan Binh TrinhTan Dat HuynhVan Dat NguyenDinh Duc Nguyenducnd@vnu.edu.vn2017-03-06T04:38:02Z2017-03-06T04:39:21Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2438This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24382017-03-06T04:38:02ZThe mechanical effect and physics properties of ZnO nanoparticles in nanocomposite organic solar cell P3HT:PCBMDinh Duc Nguyenducnd@vnu.edu.vnDinh Long Dangddlong@vnu.edu.vnXuan Nguyen Nguyen2017-03-06T04:37:52Z2017-03-06T04:37:52Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2437This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24372017-03-06T04:37:52ZHybrid Phase Field Simulation of Dynamic Crack Propagation in Functionally Graded Glass-Filled EpoxyHong Duc Doandoan.hd.amsl.eng@vnu.edu.vnQuoc Tinh BuiDinh Duc Nguyenducnd@vnu.edu.vnFushinobu Kazuyoshi2017-03-06T04:36:48Z2017-03-06T04:37:14Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2436This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24362017-03-06T04:36:48ZNonlinear stability analysis of imperfect three-phase sandwich laminated polymer nanocomposite panels resting on elastic foundations in thermal environmentsVan Thu PhamDinh Duc Nguyenducnd@vnu.edu.vn2017-03-06T04:34:41Z2017-05-23T08:35:51Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2435This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24352017-03-06T04:34:41ZVibration and nonlinear dynamic analysis of imperfect thin eccentrically stiffened functionally graded plates in thermal environmentsHong Cong PhamDinh Duc Nguyenducnd@vnu.edu.vn2017-03-06T04:29:03Z2017-03-06T04:29:36Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2433This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24332017-03-06T04:29:03ZAnalytical approach for investigating the nonlinear dynamic response of imperfect shear deformable FGM cylindrical panel subjected to blast loadsDinh Duc Nguyenducnd@vnu.edu.vnDinh Duc Nguyenducnd@vnu.edu.vnQuoc Quan Tran2017-03-06T04:28:17Z2017-03-06T04:28:56Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2432This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24322017-03-06T04:28:17ZNonlinear thermal dynamic analysis of pienzoelectric functionally graded platesDinh Duc Nguyenducnd@vnu.edu.vnPhuong TranHong Cong Pham2017-03-06T04:28:06Z2017-03-06T04:28:06Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2431This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24312017-03-06T04:28:06ZNonlinear stability of pienzoelectric functionally graded circular cylindrical shell under temperatureDuc Tuan NgoPhuong TranDinh Duc Nguyenducnd@vnu.edu.vn2017-03-06T04:25:53Z2017-03-06T04:25:53Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2430This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24302017-03-06T04:25:53ZNonlinear vibration and dynamic response of imperfect eccentrically stiffened shear deformable sandwich plate with functionally graded material in thermal environmentDinh Duc Nguyenducnd@vnu.edu.vnHong Cong PhamDuc Tuan NgoPhuong Tran2017-03-06T04:25:24Z2017-03-06T04:25:24Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2429This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24292017-03-06T04:25:24ZNonlinear vibration and dynamic response of shear deformable imperfect functionally graded double curved shallow shells resting on elastic foundations in thermal environmentsQuoc Quan TranDinh Duc Nguyenducnd@vnu.edu.vn2017-03-06T04:25:02Z2017-03-06T04:25:16Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2428This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24282017-03-06T04:25:02ZNonlinear dynamic response and vibration of an imperfect three-phase laminated nanocomposite cylindrical panel resting on elastic foundations in thermal environments.Van Thu PhamDinh Duc Nguyenducnd@vnu.edu.vn2017-03-06T04:24:25Z2017-03-06T04:24:55Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2427This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24272017-03-06T04:24:25ZThermal stability analysis of eccentrically stiffened Sigmoid – FGM plate with metal –ceramic-metal layers based on FSDTHong Cong PhamDinh Duc Nguyenducnd@vnu.edu.vn2017-03-06T04:24:19Z2017-03-06T04:24:19Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2426This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24262017-03-06T04:24:19ZNonlinear thermo-mechanical dynamic analysis and vibration of higher order shear deformable piezoelectric functionally graded material sandwich plates resting on elastic foundationsDinh Duc Nguyenducnd@vnu.edu.vnHong Cong Pham2017-03-06T04:24:10Z2017-03-06T04:24:10Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2425This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24252017-03-06T04:24:10ZNonlinear thermo-electro-mechanical dynamic response of shear deformable piezoelectric Sigmoid functionally graded sandwich circular cylindrical shells on elastic foundationsDinh Duc Nguyenducnd@vnu.edu.vn2017-03-06T04:24:00Z2017-03-06T04:24:00Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2424This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24242017-03-06T04:24:00ZNonlinear thermal dynamic analysis of eccentrically stiffened S-FGM circular cylindrical shells surrounded on elastic foundations using the Reddy’s third-order shear deformation shell theoryDinh Duc Nguyenducnd@vnu.edu.vn2017-03-06T04:23:49Z2017-03-06T04:23:49Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2420This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24202017-03-06T04:23:49ZHybrid Phase Field Simulation of Dynamic Crack Propagation in Functionally Graded Glass-Filled EpoxyHong Duc Doandoan.hd.amsl.eng@vnu.edu.vnQuoc Tinh BuiDinh Duc Nguyenducnd@vnu.edu.vnFushinobu Kazuyoshi2017-03-06T04:23:38Z2017-03-06T04:23:38Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2419This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24192017-03-06T04:23:38ZEvaluation of elastic properties and thermal expansion coefficient of composites reinforced by randomly distributed spherical particles with negative Poisson’s ratiosThe Duong NguyenDinh Duc Nguyenducnd@vnu.edu.vn2017-03-06T04:23:25Z2017-03-06T04:23:25Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2418This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24182017-03-06T04:23:25ZEffects of variable thickness and imperfection on nonlinear buckling of Sigmoid-functionally graded cylindrical panelsToan Thang PhamDinh Duc Nguyenducnd@vnu.edu.vnThoi Trung Nguyen2017-03-06T04:23:11Z2019-01-14T02:54:45Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2417This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24172017-03-06T04:23:11ZNonlinear dynamic response and vibration of sandwich composite plates with negative Poisson’s ratio in auxetic honeycombsAuxetic cellular solids in the forms of honeycombs under blast load have great potential in a diverse range of applications, including core material in sandwich plates composite components. Based on Reddy’s first-order shear deformation plate theory, this paper presents an analysis of the nonlinear dynamic response and vibration of sandwich plates with negative Poisson’s ratio in auxetic honeycombes on elastic foundations subjected to blast and mechanical loads. A three-layer sandwich plate is considered discretized in the thickness direction by using analytical methods (stress function method, approximate solution), Galerkin method, and fourth-order Runge-Kutta method. The results show the effects of geometrical parameters, material properties, mechanical and elastic foundations on the nonlinear dynamic response, and vibration of sandwich plates.Dinh Duc Nguyenducnd@vnu.edu.vnHong Cong Pham2017-03-06T04:22:44Z2017-03-06T04:22:44Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2416This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24162017-03-06T04:22:44ZEnhancement of energy conversion efficiency in organic solar cell using nanoparticlesDinh Duc Nguyenducnd@vnu.edu.vn2017-03-06T04:22:24Z2017-03-06T04:22:24Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2415This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24152017-03-06T04:22:24ZNanocompositematerials for energy conversion and storageDinh Duc Nguyenducnd@vnu.edu.vn2017-02-28T09:09:20Z2017-02-28T09:09:20Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2453This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24532017-02-28T09:09:20ZA Numerical Study of Mixed-mode Crack Propagation in ZnO2/NiCr Functionally Graded Materials by A Hybrid Phase-Field MethodMinh Phuc PhamHong Duc Doandoan.hd.amsl.eng@vnu.edu.vnQuoc Tinh BuiXuan Nguyen NguyenMinh Dung NguyenBinh Khiem NguyenDinh Duc Nguyenducnd@vnu.edu.vn2017-02-28T09:09:10Z2017-02-28T09:09:10Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2452This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24522017-02-28T09:09:10ZDynamics Crack Propagation Simulation by A Rate-dependent Phase Field Fracture ApproachHong Duc Doandoan.hd.amsl.eng@vnu.edu.vnQuoc Tinh BuiXuan Nguyen NguyenFushinobu KazuyoshiDinh Duc Nguyenducnd@vnu.edu.vn2017-02-28T09:08:50Z2017-02-28T09:08:50Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2451This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24512017-02-28T09:08:50ZA finite Element Model Using a New Third-order Shear Deformation Plate Theory for The Analysis of Heated Functionally Graded plates in High TemperatureVan Thom DoQuoc Tinh BuiHong Duc Doandoan.hd.amsl.eng@vnu.edu.vnDinh Duc Nguyenducnd@vnu.edu.vn2017-02-28T09:08:32Z2017-02-28T09:08:32Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2450This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24502017-02-28T09:08:32ZBuckling anslysis of plates with crack using FSDT and the phase-field theoryVan Thom DoHong Duc Doandoan.hd.amsl.eng@vnu.edu.vnQuoc Tinh BuiDinh Duc Nguyenducnd@vnu.edu.vn2017-02-28T09:08:02Z2017-02-28T09:08:02Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2449This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24492017-02-28T09:08:02ZThe behavior of cracks in the interface ZnO2 / NiCrHong Duc Doandoan.hd.amsl.eng@vnu.edu.vnQuoc Tinh BuiDinh Duc Nguyenducnd@vnu.edu.vn2017-02-28T09:07:45Z2017-02-28T09:07:45Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2448This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24482017-02-28T09:07:45ZApplying dynamic downscaling method with a high-resolution regional climate model for local climate projection in greater Hanoi cityQuang Van DoanKusaka HiroyukiMinh Truong NguyenHong Duc Doandoan.hd.amsl.eng@vnu.edu.vnDinh Duc Nguyenducnd@vnu.edu.vn2017-02-28T09:07:16Z2017-02-28T09:07:16Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2447This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24472017-02-28T09:07:16ZNonlinear buckling and postbuckling of an eccentrically stiffened E-FGM plate resting on elastic foudations in thermal environmentDinh Duc Nguyenducnd@vnu.edu.vnHong Cong PhamXuan Tinh Ho2017-02-28T09:07:07Z2017-02-28T09:07:07Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2446This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24462017-02-28T09:07:07ZNonlinear buckling and postbuckling of an eccentrically stiffened E-FGM circular cylindrical shells resting on elastic foundations in thermal environmentDinh Duc Nguyenducnd@vnu.edu.vnQuoc Quan TranDinh Nguyen Pham2017-02-28T09:06:55Z2017-02-28T09:06:55Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2445This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24452017-02-28T09:06:55ZNonlinear dynamic response and vibration of imperfect eccentrically stiffened E-FGM double curved shallow shells in thermal environmentsDinh Duc Nguyenducnd@vnu.edu.vnQuoc Quan Tran2017-02-28T09:06:39Z2017-02-28T09:06:39Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2444This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24442017-02-28T09:06:39ZNonlinear dynamic and vibration analysis of an eccentrically stiffened E-FGM plate in thermal environmentDinh Duc Nguyenducnd@vnu.edu.vnHong Cong PhamDinh Dat Ngo2017-02-28T09:06:24Z2017-02-28T09:06:24Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2442This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24422017-02-28T09:06:24ZOn the nonlinear dynamic and vibration stability of S-FGM spherical shells with metal-ceramic-metal layers resting on elastic foundationDinh Duc Nguyenducnd@vnu.edu.vnThuy Anh VuDinh Quang Vuquangvd2510@gmail.com2017-02-28T09:05:58Z2017-02-28T09:05:58Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2441This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24412017-02-28T09:05:58ZNumerical Failure Simulation of Quasi-Brittle Materials using A Second-Order Implicit Gradient Damage TheoryQuoc Tinh BuiA.H Tuan NguyenHong Duc Doandoan.hd.amsl.eng@vnu.edu.vnDinh Duc Nguyenducnd@vnu.edu.vnHirose Sohichi2017-02-28T09:05:40Z2017-02-28T09:05:40Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2440This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24402017-02-28T09:05:40ZNonlinear dynamic and vibration analysis of imperfect eccentrically stiffened E-FGM circular cylindrical shells surrounded by Pasternak elastic foundation in thermal environmentDinh Duc Nguyenducnd@vnu.edu.vnHong Cong PhamDuy Khanh Nguyen2017-02-28T08:25:41Z2017-02-28T08:25:41Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2422This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24222017-02-28T08:25:41ZNonlinear stability of eccentrically stiffened S-FGM elliptical cylindrical shells in thermal environmentDinh Duc Nguyenducnd@vnu.edu.vnDuc Tuan NgoPhuong TranHong Cong PhamDinh Nguyen Pham2017-02-28T08:25:32Z2017-02-28T08:25:32Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2421This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24212017-02-28T08:25:32ZNonlinear dynamic and vibration analysis of piezoelectric eccentrically stiffened FGM plates in thermal environmentDinh Duc Nguyenducnd@vnu.edu.vnHong Cong PhamDinh Quang Vuquangvd2510@gmail.com2017-01-17T02:10:24Z2017-01-17T02:10:24Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2405This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24052017-01-17T02:10:24ZHigh Accuracy Prostate Cancer Detection Using Human Blood Serum Metabolomic ProfilingProstate cancer (PCa) represents the second leading cause of cancer mortality in many western countries. Although the Prostate-Specific Antigen (PSA) test is widely used to screen for PCa, certain advisory groups recommend against its use because it suffers from false positive results and over-treatment. These drawbacks have led to the increased interest of using metabolite profiling to discover new differential biomarkers that could improve the specificity of PCa diagnosis.1 In this work,2 untargeted metabolomic profiling of age-matched serum samples from PCa patients and healthy individuals was performed using ultraperformance liquid chromatography coupled to high-resolution tandem mass spectrometry and machine learning methods. PCa was detected in serum samples with 92.1% sensitivity, 94.3% specificity, and 93.0% accuracy by means of a metabolite-based in vitro diagnostic multivariate index assay, which outperformed the prevalent PSA test. Within the panel of 40 metabolic spectral features that was found to be differential, 31 metabolites were identified by MS and MS/MS, with 10 further confirmed by standards. Numerous discriminant metabolites were mapped in the steroid hormone biosynthesis pathway. The identification of fatty acids, amino acids, lysophospholipids, and bile acids provided further insights into the metabolite alterations associated with the disease. Our current work involves the prospective analysis of a larger sample cohort (n=500) that includes samples from PCa patients before and after undergoing surgery, patients with benign prostatitis, and healthy individuals with measured PSA values, in order to evaluate the influence of ethnicity and cohort size on the robustness of the metabolic biomarker panel that we have previously found, and to discover biomarkers useful for follow-up care.ME Mongemaria.monge@cibion.conicet.gov.arX ZangCM JonesQuoc Long Tranlongtq@vnu.edu.vnManshui ZhouDeEtte Walker L.Roman MezencevAlexander GrayJohn F. McDonaldFacundo Fernandez2017-01-13T02:31:03Z2017-01-13T02:31:03Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1871This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18712017-01-13T02:31:03ZExploiting GPU for Large Scale Fingerprint IdentificationHong Hai LeNgoc Hoa Nguyenhoa.nguyen@vnu.edu.vnTri Thanh Nguyenntthanh@vnu.edu.vn2017-01-12T15:55:15Z2017-01-12T15:55:15Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2401This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24012017-01-12T15:55:15ZA hybrid approach to Vietnamese word segmentationWord segmentation is the very first task for Vietnamese language processing. Word-segmented text is the input of almost other NLP tasks. This task faces some challenges due to specific characteristics of the language. As in many other Asian languages such as Japanese, Korean and Chinese, white spaces in Vietnamese are not always used as word separators and a word may contain one or more syllables. In this paper, we propose an efficient hybrid approach to detect word boundary for Vietnamese texts using logistic regression as a binary classifier combining with longest matching algorithm. First, longest matching algorithm is used to catch words that contain more than two syllables in input sentence. Next, the system utilizes the classifier to determine the boundary of 2-syllable words and proper names. Then, the predictions having low confidence conducted by the classifier are verified by a dictionary to get the final result. Our system can achieve an F-measure of 98.82% which is the most accurate result for Vietnamese word segmentation to the best of our knowledge. Moreover, the system also has a high speed. It can run word segmentation for nearly 34k tokens per second.Tuan Phong Nguyentuanphong94@gmail.comAnh Cuong Lecuongla@vnu.edu.vn2017-01-12T11:46:22Z2017-01-12T11:46:22Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2403This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24032017-01-12T11:46:22ZThe Index-based Optical Spatial Modulation Scheme
in Optical MIMOOptical Multi-input Multi-output (O-MIMO) is
considered as an effective solution in order to achieve high
performance for Visible Light Communication (VLC) systems.
However, O-MIMO systems are faced with the impact of InterChannel Interference (ICI) which results in system performance
decrease. In this paper, a novel Index-based Optical Spatial
Modulation (IOSM) is proposed to remove ICI and increase
spectrum efficiency for indoor VLC systems applying O-MIMO.
In our proposed scheme, the signals are DC biased for intensity
modulation and direct detection (IM/DD) and a Maximumlikelihood (ML) decoder decision to maximize the signal-to-noise
ratio (SNR) at the receiver. Computer simulation results show
that the proposed scheme outperforms previously proposed
spatial modulation schemes in O-MIMO systems.Ngoc-Tan Nguyennguyen.tan170@gmail.comQuoc-Tuan Nguyentuannq@vnu.edu.vnNam-Hoang Nguyenhoangnn@vnu.edu.vn2017-01-12T11:46:10Z2017-01-12T11:46:10Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2402This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24022017-01-12T11:46:10ZLight Beam Allocation Algorithm for Eliminating
Interference in Visible Light CommunicationsIn this paper, we present a model of visible light
communication (VLC) systems which exploit light beams for
downlink transmission. A calculation method is proposed for light
beam configuration which guarantees no blind areas in the whole
VLC coverage while minimizing the number of light beams. As a
major contribution in this paper, a light beam allocation algorithm
is proposed which aims to eliminate interferences between inter
VLC Access Points (inter-APs) by using information of incoming
data queue length and co-channel interference (CCI) conditions to
decide which VLC beams are used for transmitting data to
appropriate user equipments (UEs). By deploying the proposed
algorithm, CCI can be eliminated because noise-effected regions
and noise-free regions can be separated. Performance of the novel
light beam allocation algorithm is analyzed, evaluated and then
compared with that of another light beam allocation method using
the Round-Robin algorithm. Performance results show that there
are significantly improvements in SINR, user throughput and
packet delay parameters when deploying the proposed light beam
allocation algorithm.Duc-Quan Nguyenquannd57@gmail.comNgoc-Tan Nguyennguyen.tan170@gmail.comNam-Hoang Nguyenhoangnn@vnu.edu.vnKeattisak Spirinmanwatkeattisak.sripimanwat@gmail.com2017-01-12T09:42:56Z2017-01-12T09:42:56Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2404This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24042017-01-12T09:42:56ZĐánh giá hiệu năng của các thuật toán phân bổ tài nguyên trong mạng truyền thông ánh sáng nhìn thấy sử dụng các chùm sáng định hướngPhân bổ tài nguyên là một trong những bài toán cấp
thiết trong các hệ thống truyền thông đa truy cập. Trong bài báo
này, chúng tôi sẽ đánh giá hiệu năng của ba thuật toán phân bổ tài
nguyên là Round Robin, LBAA (Light Beam Allocation
Algorithm) và thuật toán đề xuất i-LBAA (improved Light Beam
Allocation Algorithm) sử dụng cấu hình các chùm sáng định
hướng (beam). Các mô phỏng trên máy tính được thực hiện với hệ
thống sử dụng thuật toán i-LBAA, LBAA và Round Robin để so
sánh hiệu năng của hệ thống khi sử dụng các thuật toán thông qua
các tham số tỉ lệ tín hiệu trên tạp âm SINR, thông lượng và độ trễ
trung bình của các gói tin.Dinh Nguyen Nguyennguyennd.1995@gmail.comDuc Quan Nguyenquannd57@gmail.comNgoc Tan Nguyennguyen.tan170@gmail.comNam Hoang Nguyenhoangnn@vnu.edu.vn2017-01-08T08:09:06Z2017-01-08T08:09:06Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2400This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/24002017-01-08T08:09:06ZTilt sensor based on three electrodes dielectric liquid capacitive sensorDang Dinh Tiepdangtiep.2011@gmail.comBui Ngoc Mymybuingoc@gmail.comVu Quoc Tuanvqtuan0211@gmail.comPham Quoc Thinhphamquocthinh@gmail.comTran Minh Cuongcuongtm2@vnpt-technology.vnThanh Tung Buitungbt@vnu.edu.vnDuc Trinh Chutrinhcd@vnu.edu.vn2017-01-08T08:08:24Z2017-01-08T08:08:24Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2398This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23982017-01-08T08:08:24ZIon Wind Generator Utilizing Bipolar Discharge in Parallel Pin GeometryThanh Van Daudauv@sc.sumitomo-chem.co.jpThien Xuan Dinhthien@cfd.ritsumei.ac.jpTerebessy Tibortibor.terebessy@clearviewtraffic.comThanh Tung Buitungbt@vnu.edu.vn2017-01-08T08:07:48Z2017-01-08T08:07:48Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2397This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23972017-01-08T08:07:48ZBipolar corona assisted jet flow for fluidic applicationVan Thanh Daudauv@sc.sumitomo-chem.co.jpThien Xuan Dinhthien@cfd.ritsumei.ac.jpThanh Tung Buitungbt@vnu.edu.vnTibor Terebessytibor.terebessy@clearviewtraffic.com2017-01-06T07:07:58Z2017-01-06T07:07:58Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2395This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23952017-01-06T07:07:58ZA peer assessment approach to project based blended learning course in a Vietnamese higher educationThis article presents a model using peer assessment to evaluate students taking part in blended - learning courses (BL). In these courses, teaching activities are carried out in the form of traditional face-to-face (F2F) and learning activities are performed online via the learning management system Moodle. In the model, the topics of courses are built as a set of projects and case studies for the attending students divided into groups. The result of the implementation of projects is evaluated and ranked by all course participants and is one of the course evaluation criteria for lecturers. To assess learners more precisely, we propose a multi-phase assessment model in evaluating all groups and the group members. The result of each student in the group based on himself evaluation, evaluations of the team members, the tearcher and all students in the course. There are 107 students, who participated in the course entitled ``web application development'', are divided into 20 groups conducting the course in the field of information technology is deployed in the form of blended learning through peer assessment. The results of student's feedback suggested that the usage of various peer assessment created positive learning effectiveness and more interesting learning attitude for students. The survey was conducted with the students through the questionnaire, each question with scale 5-point Likert scale that ranged from 1 (very unsatisfied) to 5 (very statisfied) to investigate the factors: Collaboration, Assessment, Technology showed that students were satisfied with our approach.Viet Anh Nguyenvietanh@vnu.edu.vn2017-01-06T07:05:04Z2017-01-06T07:05:04Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2393This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23932017-01-06T07:05:04ZExamining student’s satisfaction with online learning activities in blended learning course: a case studyViet Anh Nguyenvietanh@vnu.edu.vn2017-01-06T02:35:29Z2017-01-06T02:35:29Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2392This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23922017-01-06T02:35:29ZA Novel Behavior based Navigation Architecture of Mobile Robot in Unknown EnviromentsThi Thanh Van Nguyenvanntt@vnu.edu.vnManh Duong Phungduongpm@vnu.edu.vnAnh Viet Dangvietda@vnu.edu.vnQuang Vinh Tranvinhtq@vnu.edu.vn2017-01-05T02:42:24Z2017-01-05T02:42:24Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2353This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23532017-01-05T02:42:24ZHigh accuracy electronic compass for detecting azimuth direction based on a novel magnetoelectric effectMost navigation systems today use compass to determine heading direction based on determining the earth’s magnetic fields in a horizontal plane. There are several types of electronic compasses based on different effects such as fluxgate, magnetoresistive, and magnetoinductive. This paper presents a novel electronics compassing for navigation system, a modification of the conventional magnetic compass, which based on magnetoelectric effect. Recent researches have shown that thanks to enhancement of shape magnetic anisotropy of Metglas ribbon, an high magnetic sensitivity (~Voltage/Tesla), and extremely high accurary (1 nanoTesla) geomagnetic sensors based on Metglas/PZT magnetoelectric laminate were built [1]. By intergrating 2-axis sensor with an electronic circuit and 12-bit ADC (Fig. 1), a high resolution magnetoelectric compass containing anplifcation, automatic degaussing, offset cancellation that enables 0.1 degree compass heading accuracy. This kind of magnetoelectric compass would contribute to the most sensitive and high accuracy electronic compass available in the industry todayThi Huong Giang Dogiangdth@vnu.edu.vnHuu Duc Nguyenducnh@vnu.edu.vn2017-01-05T02:39:45Z2017-01-05T02:39:45Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2345This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23452017-01-05T02:39:45ZStress Electro-Cardiogram Instrumentation: Principles and StructureElectrocardiography, nowadays, is an essential part of the initial evaluation for patients presenting with cardiac complaints. However, an normal electrocardiography can not eliminate absolutely the heart disease. For example, in the case our heart rate is irregular and appears intermittently, if ECG is mearsured between the attacks, it will be normally. Also, not all cases of myocardial infarction were detected by normal ECG and angina is a typical case. At that time, we will need to consider a special ECG – Stress (Exercise) Echocardiography. Stress echo is done as part of a stress test. During a stress test, patients exercise or take medicine (given by doctor) to make their heart work hard and beat fast. A technician will use echo to create pictures of patients’ heart before they exercise and as soon as they finish. Some heart problems, such as coronary heart disease, are easier to diagnose when the heart is working hard and beating fast. To meet the demands of this procedure, a stress electro-cardiogram instrumentation wil be used in order to observe and store the whole process. Generally, such this system consists of three main units: exercise equipment (treadmill/stationary bicycle), special ECG device and a supported computer system. By considering appropriate components, a stress ECG instrumentation can be designed and integrated completely.Manh Thang Phamthangpm@vnu.edu.vnNgoc Viet Nguyenvietnn@vnu.edu.vnVan Manh Hoangmanhhv87@vnu.edu.vnNgoc Linh Nguyennlnguyen@vnu.edu.vn2017-01-05T02:35:29Z2017-01-05T02:35:29Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2363This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23632017-01-05T02:35:29ZMô hình nứt nẻ liên tục (CFM) cho các vỉa nứt nẻ và áp dụng cho tầng móng mỏ Bạch HổCác vỉa nứt nẻ được mô hình hóa thành các mô hình nứt nẻ liên tục (CFM) với các thông số đặc trưng là mật độ và độ mở nứt nẻ trung bình. Các phương pháp Fuzzy logic và trí tuệ nhân tạo (ANN) được phát triển để xác định thông số mô hình CFM trên lưới địa chất toàn vỉa thông qua các thuộc tính địa chấn và các dữ liệu tại các giếng. Dữ liệu khảo sát tại giếng dùng để xác định các thông số cho mô hình tại các ô lưới chứa giếng. Thuật toán Fuzzy logic dùng để đánh giá tương giữa các thuộc tính địa chấn và các thông số của mô hình CFM. Thuật toán ANN được sử dụng để xác định quan hệ giữa các thuộc tính địa chấn và thông số của mô hình CFM tại các ô giếng, sau đó thác triển các thông số này cho toàn vỉa. Các chương trình tính toán của mô hình được viết bằng ngôn ngữ FORTRAN. Kết quả đã được kiểm tra và thử nghiệm áp dụng để xác định độ thấm cho tầng móng mỏ Bạch Hổ và cho kết quả tốt.The Ba Dangbadt@vnu.edu.vnQuang Thai Nguyen2017-01-05T02:33:16Z2017-01-05T02:33:16Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2285This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22852017-01-05T02:33:16ZOn the nonlinear stability of eccentrically stiffened functionally graded annular spherical segment shellsDinh Duc Nguyenducnd@vnu.edu.vnHuy Bich DaoThi Thuy Anh Vuanhvutt@vnu.edu.vn2017-01-05T02:31:33Z2017-01-05T02:31:33Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2282This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22822017-01-05T02:31:33ZOn the linear stability of eccentrically stiffened functionally graded annular spherical shell on elastic foundationsThi Thuy Anh Vuanhvutt@vnu.edu.vnHong Cong PhamHuy Bich DaoDinh Duc Nguyenducnd@vnu.edu.vn2017-01-04T13:42:09Z2017-01-04T13:42:10Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2389This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23892017-01-04T13:42:09ZA Comprehensive Lighting Configuration for Efficient Indoor
Visible Light Communication NetworksDesign of an efcient indoor visible light communication (VLC) system requires careful considerations on both illumination and
communication aspects. Besides fundamental factors such as received power and signal-to-noise ratio (SNR) level, studies on
mobility scenarios and link switching process must be done in order to achieve good communication link quality in such systems.
In this paper, a comprehensive lighting confguration for efcient indoor VLC systems for supporting mobility and link switching
with constraint on illumination, received power, and SNR is proposed. Full connectivity in mobility scenarios is required to make
the system more practical. However, different from other literatures, our work highlights the signifcance of recognizing the main
influences of feld of view angle on the connectivity performance in the practical indoor scenarios. A flexible link switching initiation
algorithm based on the consideration of relative received power with adaptive hysteresis margin is demonstrated. In this regard, we
investigate the effect of the overlap area between two light sources with respect to the point view of the receiver on the link switching
performance. Te simulation results show that an indoor VLC system with sufcient illumination level and high communication
link quality as well as full mobility and support link switching can be achieved using our approach.Thai-Chien Buiuetchien@gmail.comSuwit Kiravittayasuwitki@gmail.comKeattisak Sripimanwatkeattisak.sripimanwat@gmail.comNam Hoang Nguyenhoangnn@vnu.edu.vn2017-01-04T03:26:58Z2017-01-04T03:26:58Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2221This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22212017-01-04T03:26:58ZOn the thermal buckling analysis of functionally graded plates with internal defects using extended isogeometric analysisTiantang YuQuoc Tinh BuiShuohui YinHong Duc Doandoan.hd.amsl.eng@vnu.edu.vnC.T. WuVan Thom DoSatoyuki Tanaka2017-01-04T03:25:53Z2017-01-04T03:25:53Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2220This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22202017-01-04T03:25:53ZBessel beam laser-scribing of thin film silicon solar cells by ns pulsed laserHong Duc Doandoan.hd.amsl.eng@vnu.edu.vnRyoichi IIDAByunggi KIMIsao SATOHKazuyoshi FUSHINOBU2016-12-31T14:34:59Z2016-12-31T14:34:59Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2339This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23392016-12-31T14:34:59ZThe mechanical effect and physics properties of ZnO nanoparticles in nanocomposite organic solar cell P3HT:PCBMDoping particles into composite materials can mechanically stabilize these structure. At nanoscale, doping nanoparticles not only strengthen the material structure but also improve some mechanical and physical properties of materials. In this work, we will investigate the role of ZnO nanoparticles (NPs) doping into the nanocompsite multilayer organic solar cell (OSC) with the active layer composed of P3HT:PCBM. ZnO NPs is an economical ingredient for some applications in organic solar cell devices. They not only enhance significantly the absorption of the incident light but also make the composite nanostructure in OSC more durable. The absorption properties such as the absorption intensity can be explained by Mie scattering theory and studied numerically using finite element method (FEM). The mechanical effects can be illustrated by Young and Bulk modulus.Dinh Long Dangddlong@vnu.edu.vnDinh Duc Nguyenducnd@vnu.edu.vn2016-12-31T14:32:56Z2016-12-31T14:32:56Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2347This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23472016-12-31T14:32:56ZResearch on improving aerodynamic performance of an UAV airfoil using numerical simulation methodThis paper shows research results which allow improving the aerodynamic performance of an UAV airfoil through the modeling and simulation of aerodynamic flow around an airfoil using Computational Fluid Dynamics (CFD) tools. Firstly, a model of wing with the NACA4415 across area is considered under the effect of low speed air flow at different coming angles. The aerodynamic characteristics of this airfoil will be simulated, calculated and analyzed. Based on the analysis, the author proposes a new design of UAV airfoil in order to improve the aerodynamic performance of the wing. Several profiles of proposed design have been investigated in the similar airstream conditions with respect to the initial one by using the numerical simulation method on COMSOL software. The results show the good response of the new design. This research can apply for the design and construction tasks about unmanned aerial vehicle (UAV) in Vietnam.Ngoc Viet Nguyenvietnn@vnu.edu.vnVan Manh Hoangmanhhv87@vnu.edu.vnNgoc Linh Nguyennlnguyen@vnu.edu.vn2016-12-31T14:30:59Z2016-12-31T14:30:59Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2336This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23362016-12-31T14:30:59ZThe Physics of Spin-1/2 XY Model with Four-Site Exchange Interaction on the Kagome LatticeThe quantum spin liquid (QSL) state, proposed more than three decades ago by Fazekas and Anderson remains surprisingly elusive. Although recent experiments provide a strong evidence of their existence in the frustrated spin systems, the microscopic model for this state is still rare. The extensive theoretical framework, developed over decades, continues to extend further motivated by these and other discoveries from large-scale computer simulations of a relatively small number of models. In this work, we discuss the physics of the ground-state phase diagram of a two- dimensional Kagome lattice spin-1/2 XY model with a four-site ring-exchange interaction using quantum Monte Carlo simulation. We found the second order phase transition from superfluid state to a Z2 quantum spin liquid phase driven by the four-site ring exchange interaction. We have characterized the QSL by its vanishing order parameters such as the spin-spin structure factor, the plaquette-plaquette structure factor. Moreover, we have found the large anomalous exponent ηXY* ≈ 1.325 which belongs to a different universality class other than 3D XY universality class. There is no signal of supersolid phase intervening between the superfluid state and QSL state.Thi Kim Oanh NguyenThanh Dai PhamDinh Long Dangddlong@vnu.edu.vn2016-12-31T14:28:29Z2016-12-31T14:28:29Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2334This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23342016-12-31T14:28:29ZElectric-field Control of a Spin “bit” Configuration in MERAM Model: A Monte Carlo StudyMagnetoelectric (ME) effect can be realized in multiferroic composites composed of the alternative ferromagnetic (FM) and ferroelectric (FE) multilayer such as FM layer grown on top of FE layer (FM/FE). In this work, we have shown that the spin orientation in FM layer can be controlled by using the electrical field indirectly via the elastic mechanism between these layers. There is a critical electric field for each FM layer such as Fe, Fe3O4, which is the minimum electric field to switch the spin to the different directions in space. The Monte Carlo simulation has been applied for the anisotropy model taken into account the magnetocrystalline anisotropy and shape anisotropy as well as the effective anisotropy field. The particular spin switching, i.e. an angle of 90 degree switching, corresponding to bit “0” and “1” switching in magnetoelectric random access memory (MERAM) will be discussed.Long Dangddlong@vnu.edu.vn2016-12-31T14:23:58Z2017-01-13T02:26:34Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2253This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22532016-12-31T14:23:58ZA survey for wireless sensor network applicationsWireless Sensor Networks (WSNs) are an emerging technology for low-cost with vital applications such as unattended monitoring of a wide range of environmental parameters and target tracking. This has been enabled by the availability, particularly in recent years, of sensors that are smaller, cheaper, and intelligent. These sensors are equipped with wireless interfaces that they can communicate with one another to create a network. The design of a WSN depends significantly on the applications, and it must consider factors such as the environment, the application’s design objectives, cost, hardware, and system constraints. This work not only discusses about their potential advantages and disadvantages but also gives an overview of several new applications and identifies the research challenges associated with such applications.
Key Words: Wireless sensor networks; Sensor network services; ZigBee; Sensor network deployment.Thai Son Transon.th.tran@gmail.comVan Manh Hoangmanhhv87@vnu.edu.vnManh Thang Phamthangpm@vnu.edu.vn2016-12-31T14:23:03Z2016-12-31T14:23:03Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2269This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22692016-12-31T14:23:03ZMeasurement of Iron-Oxide Fluids Using a Magnetoelectric SensorIron oxide fluids have been measured by using a magnetoelectric (ME) effect - based magnetic sensor with a long-type sandwiched composite of Metglass/PZT/Meglass laminates of 1×15 mm2 in dimension. In homogeneous magnetic fields, the sensor exhibits a sensitivity of 307.453 mV/Oe. The minimum measurable signal (i.e. noise level) of this experimental setup was found as small as 0.782 mV, which reveals a possible detection limit of 3×10−8 emu . Our report presents the simulation and the measurement of magnetic fluids of various magnetic Fe3O4 nanoparticle concentrations. The results open a possibility of using this sensor for medical and bioengineering applications.Xuan Toan NguyenThi Huong Giang Dogiangdth@vnu.edu.vnHuu Duc Nguyenducnh@vnu.edu.vn2016-12-31T14:20:18Z2016-12-31T14:20:18Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2335This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23352016-12-31T14:20:18ZPreparation and characterization of nanorod-like TiO2 and ZnO films used for charge- transport buffer layers in P3HT based organic solar cellsWith the aim of findingout the appropriate buffer layers for organic solar cells (OSC), TiO2 and ZnO on ITO/glass were prepared as nanorod-like thin films. The TiO2 films were crystallyzed in the anatase phase and the ZnO films, in the wurtzite structure. The nanorods in both the fims have a similar size of 15 to 20 nm in diameter and 30 to 50 nm in length. The nanorods have an orientation nearly perpendicular to the ITO-substrate surface. From UV-Vis data the bandgap of the TiO2 and ZnO films were determined tobe 3.26 eV and 3.42 eV, respectively. The laminar organic solar cells with added TiO2 and ZnO, namely ITO/TiO2/P3HT:PCBM/LiF/Al (TBD) and ITO/ZnO/P3HT:PCBM/LiF/Al (ZBD)were made for characterization of the energy conversion performance. As a result, comparing to TiO2,the nanorod-likeZnO filmwas found to be a much better buffer layer that made the fill factor improve from a value of 0.60 for TBD to 0.82 for ZBD, and consequently thePCE was enhanced from 0.84 for TBD to 1.17% for ZBD.Thi Thao Tranthaott@vnu.edu.vnDinh Long Dangddlong@vnu.edu.vnVan Truong VoNang Dinh Nguyendinhnn@vnu.edu.vn2016-12-31T14:13:53Z2016-12-31T14:13:53Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2219This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22192016-12-31T14:13:53ZOn the high temperature mechanical behaviors analysis of heated functionally graded plates using FEM and a new third-order shear deformation plate theoryQuoc Tinh BuiVan Thom DoLan Hoang That TonHong Duc Doandoan.hd.amsl.eng@vnu.edu.vnSatoyuki TanakaDat Tien PhamThien-An Nguyen-VanTiantang YuSohichi Hirose2016-12-31T14:12:06Z2016-12-31T14:12:06Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2218This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22182016-12-31T14:12:06ZHybrid phase field simulation of dynamic crack propagation in functionally graded glass-filled epoxyHong Duc Doandoan.hd.amsl.eng@vnu.edu.vnQuoc Tinh BuiDinh Duc Nguyenducnd@vnu.edu.vnKazuyoshi Fushinobu2016-12-31T14:10:55Z2016-12-31T14:10:55Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2217This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22172016-12-31T14:10:55ZHigh frequency modes meshfree analysis of Reissner–Mindlin platesQuoc Tinh BuiHong Duc Doandoan.hd.amsl.eng@vnu.edu.vnVan Thom DoSohichi HiroseDinh Duc Nguyenducnd@vnu.edu.vn2016-12-31T14:09:17Z2016-12-31T14:09:17Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2216This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22162016-12-31T14:09:17ZMechanism of TCO thin film removal process using near-infrared ns pulse laser: Plasma shielding effect on irradiation directionByunggi KimRyoichi IidaHong Duc Doandoan.hd.amsl.eng@vnu.edu.vnKazuyoshi Fushinobu2016-12-31T14:08:09Z2016-12-31T14:08:09Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2215This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22152016-12-31T14:08:09ZEnhanced nodal gradient 3D consecutive-interpolation tetrahedral element (CTH4) for heat transfer analysisMinh Ngoc NguyenQuoc Tinh BuiThien Tich TruongNgoc Anh TrinhIndra Vir SinghTiantang YuHong Duc Doandoan.hd.amsl.eng@vnu.edu.vn2016-12-31T14:06:47Z2016-12-31T14:06:47Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2214This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22142016-12-31T14:06:47ZNumerical modeling of 3-D inclusions and voids by a novel adaptive XFEMZhen WangTiantang YuQuoc Tinh BuiNgoc Anh TrinhThi Hien Luong NguyenDinh Duc Nguyenducnd@vnu.edu.vnHong Duc Doandoan.hd.amsl.eng@vnu.edu.vn2016-12-31T10:22:45Z2016-12-31T10:22:45Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2380This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23802016-12-31T10:22:45ZLipid biosynthesis of ten Thraustochyrid strains isolated from mangrove Xuan Thuy, Nam DinhThe features of polyunsaturated fatty acid-PUFA structures were corresponded to each separate functions as adjusting the cellular physiology and gene expression. Therefore, lack of PUFA could lead to abnormalities in skin, kidney, neural networks, immune responses and inflammation; cardiovascular, endocrine, respiratory and reproductive systems. In fish oil, PUFA content were low, thus it was difficult to produce on a large scale. Therefore, the exploration of PUFA sources particularly as arachidonic acid-AA, eicosapentaenoic acid EPA, docosapentaenoic acid-DPA/DHA attracted many researches. Heterotrophic microalgae Thraustochytrids were capable of producing high amounts of DHA and PUFA composition varied. DHA can be synthesized by the metabolism of AA, EPA and DPA. The different types of PUFA reflected relationships in classification. Ten heterotrophic microalgae thraustochytrids isolated from mangrove Xuan Thuy, Nam Dinh contain fatty acid composition varied from C12 to C28. Especially, they had two important fatty acids of PUFA as EPA and DPA. Polyunsaturated fatty acids - PUFA content of ten thraustochytrid strains were from 28.95 to 49.62% total lipid. DPA compared to other PUFA were high for all thraustochytrid strains studied, accounting 20.22 to 39.35% TFA. Ten thraustochytrid strains had the highest growth with carbon source as glucose, total lipid reached 7 to 12.35 % dry weight biomass after 72 hours. Growth rate and lipid biosynthesis in organic nitrogen source were higher than in inorganic nitrogen sources. The best source of nitrogen for growth and lipid biosynthesis of ten thraustochytrid strains is yeast extract, total lipid were 8.57 to 18.87% dry weight biomass after 72 hours.Thi Bich Dao PhamDinh Tuan NguyenDang Khoa Trankhoatd@vnu.edu.vnThi Huyen ChuHoang Thanh DoThi Hoai Ha Nguyen2016-12-31T10:21:25Z2016-12-31T10:21:25Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2211This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22112016-12-31T10:21:25ZDetection of magnetic nanoparticles using simple AMR sensors in Wheatstone bridgeWheatstone bridges incorporating a serially connected ensemble of simple AMR elements of Ni80Fe20 film were produced, targeting an application of a pinned magnetic field along the sensing magnetoresistor length. For the optimal dimension, the magnetoresistive element with length l 4 µm, width 150 µm and thickness 5 nm still shows a rather modest AMR ratio (of about 0.85% only). However, the resulting bridge exhibits a sensitivity as large as 2.15 mV/Oe. This is according to a standard sensitivity of 1.80 mV/V/Oe and a detection limit better than 10_6 emu, which is almost doubled with respect to that in the typical commercial AMR devices and is comparable with Permalloy based PHE sensor. This is suitable to detect the superparamagnetic fluid of 50 nm-Fe3O4-chitosan.Khac Quynh LeDinh Tu Buibuidinhtu@vnu.edu.vnXuan Dang DangQuoc Viet DongThi Hien Lelehien@vnu.edu.vnThi Huong Giang Dogiangdth@vnu.edu.vnHuu Duc Nguyenducnh@vnu.edu.vn2016-12-31T10:18:46Z2016-12-31T10:18:46Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2212This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22122016-12-31T10:18:46ZDetection of magnetically labeled DNA by a magnetic sensor
operating with a disposable cardDisposable cards with immobilized bioreceptors are being increasingly investigated and developed in biomedical analysis systems because they have significant advantages. In our work, a biosensor system consisting of an anisotropic magnetoresistive (AMR) sensor operating with a disposable card was developed for magnetically labeled DNA detection. The SPA/SAA/APTES/PDMS/Si as-prepared disposable card involves DNA probes specific for the 16S rRNA gene of Streptococcus suis. A single-stranded target DNA was hybridized with the DNA probe on the disposable card, which was subsequently magnetically labeled with superparamagnetic beads for detection using the AMR sensor. An almost linear response between the output signal of the AMR sensor and amount of single-stranded target DNA varied from 4.5 to 18 pmol was identified. This novel approach opens up new possibilities for the development of a sensitive, easy to use and low-cost DNA biosensor system.Thi Hien Lelehien@vnu.edu.vnKhac Quynh LeThi Huyen VuThi Yen NguyenDinh Tu Buibuidinhtu@vnu.edu.vnHong Nhung PhamThi Huong Giang Dogiangdth@vnu.edu.vnHuu Duc Nguyenducnh@vnu.edu.vn2016-12-31T10:14:37Z2016-12-31T10:14:37Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2352This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23522016-12-31T10:14:37ZAspects of nondestructive detections using a magnetoelectric sensorThis article deals with the state-of-the-art techniques in the field of nondestructive (and/or distance) detections. Illustrations are described for a wide range of applications from local evaluations of magnetic nanoparticles at a depth of several centimeters in the body during clinical interventions to blood pulse analysis and pipe and cable monitoring. Developments are implemented using a magnetoelectric based magnetic sensor with a long type sandwich Metglas/PZT/Meglas laminate composite of 1×15 mm2 dimension. In the resonant mode, the sensor exhibits a sensitivity better than 200 mV/Oe and a detection limit of 3×10−8 emu. This method can detect a spot with at least 50 µg iron oxide magnetic nanoparticles at a distance of about 10 mm from the skin surface. For the radial pulse analysis, thanks to the disturbance created by blood flowing through a localized magnetic field, not only the information of the heard rate, but also the radial blood flow waveforms are monitored (fig. 1), which strongly supports the traditional Chinese medicine. Moreover, this universal detector type can also be performed for locating wood, metal, copper, iron and live wires in the walls. It is indispensable tools for any contractors in the building who have to drill holes into walls as well as building inspectors who want to making a report on a site. The magnetoelectric sensors, thus, exhibit a high potential of applications.Thi Huong Giang Dogiangdth@vnu.edu.vnHuu Duc Nguyenducnh@vnu.edu.vn2016-12-31T10:11:21Z2016-12-31T10:11:21Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2382This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23822016-12-31T10:11:21ZDesigning and Analyzing of a Dual-Buoy 5kW Wave Energy ConverterOcean wave energy is a renewable energy source with a large potential to contribute to the world’s electricity production. The work presented in this article is intended to calculate and analyze a dual-buoy 5kW wave energy converter. This device consists of two-body point absorber, one floating body and one semi-submerged body, which moves inside a tube. A linear permanent magnet generator that is a direct-driven conversion mechanism connects two bodies. In this article, a simple modeling approach for the linear permanent magnet generator is presented and its structure is described.The Ba Dangbadt@vnu.edu.vnVan Tien DoanHoang Quan Nguyenquannh@vnu.edu.vn2016-12-31T10:09:19Z2016-12-31T10:09:19Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2348This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23482016-12-31T10:09:19ZA Study on Low-Speed Wind Tunnel – Theory and ExperimentA wind tunnel is an important tool used in aerodynamic field to investigate the effects of airstream moving through solid objects. In this paper, a low-speed wind tunnel with a cross section of 50250mm of working area and a free low velocity from 0 up to 27 m/s was considered. This model includes 30 differential pressure sensors, allows us to measure the pressure along the tunnel. In order to operate the system, a human-machine interface (HMI) in LabVIEW environment has been built. It allows us to modify the experimental parameters as well as display and collect the data. A number of tests with the model are carried out. The study shows that the results obtained from the experimental model are well agreed with the fluid dynamic theory. It shows that the low-speed wind tunnel proposed in this research can be used to study flow phenomena as well as to investigate the aerodynamic charateristics of testing objects.Minh Triet NguyenVan Long NguyenNgoc Viet NguyenNgoc Linh Nguyennlnguyen@vnu.edu.vnManh Thang Phamthangpm@vnu.edu.vn2016-12-31T10:08:05Z2016-12-31T10:08:05Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2386This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23862016-12-31T10:08:05ZDesigning and developing of a stabilizer for direct-driven wave energy converterThiết bị chuyển đổi năng lượng sóng biển cơ cấu trực tiếp dung máy phát tịnh tiến có ưu điểm đơn giản, độ tin cậy cao, dễ triển khai. Tuy nhiên, đặc trưng nguồn điện không ổn định cao là rào cản lớn nhất cho sự phát triển của thiết bị này trong thực tế. Phát triển bộ biến đổi, ổn định dòng điện cho đầu ra của các thiết bị phát điện từ các nguồn năng lượng tái tạo như sóng, gió, mặt trời…, với đặc trưng chung là đầu ra không ổn định, là nhu cầu cần thiết và đang được quan tâm nhiều trên thế giới và cả Việt Nam.
Báo cáo trình bày một số kết quả phát triển mô hình và thiết kế chế tạo bộ biến đổi điện đầu ra 3 pha cho máy phát điện tịnh tiến công suất 40W dung cho thiết bị chuyển đổi năng lượng sóng cơ cấu trực tiếp với máy phát điện tinh tiến. Từ các tham số đặc trưng đầu ra của máy phát điện đang phát triển, như biên độ điện áp, dòng điện đầu ra, đã xây dựng sơ đồ mạch nguyên lí, mô hình tính toán mô phỏng, thiết kế và phát triển mạch điện tử. Kết quả kiểm tra thực tế bằng thực nghiệm cho kết quả là nguồn điện ổn định một chiều 12V cho nhiều mục đích sử dụng khác nhau như nạp ắc quy, thắp đèn chiếu sáng và các dụng cụ điện công suất nhỏ. Nghiên cứu cũng là cơ sở cho tính toán thiết kế, chế tạo các bộ biến đổi ổn định điện công suất lớn hơn cho mục đích khai thác sử dụng năng lượng tái tạo, đặc biệt là năng lượng sóng.Van Duc NguyenThe Ba Dangbadt@vnu.edu.vnThang Long Nguyenlongnt@vnu.edu.vn2016-12-31T10:06:32Z2016-12-31T10:06:32Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2201This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22012016-12-31T10:06:32ZLight Absorption And Luminescence Properties of the Blend Pol(N-Vinylcarbazole)/Poly(N-Hexylthiophene)We have investigated the enhancement of light absorption and luminescence properties of the blend conducting polymers using poly(N-vinylcarbazole) and poly(N-hexylthiophene). The optimizedmaterial showed a broad absorption in the region from ultra violet to near infra-red and the better of luminescence ability than the pristine conducting polymers. The remarkable improvements in photoluminescence of the blends provide useful information to the application of this material in fabrication of optical – electronic devices.Phuong Hoai Nam Nguyennamnph@vnu.edu.vnMai Ha HoangTrinh Tung NgoDinh Long Dangddlong@vnu.edu.vnKhac Quan NguyenDuy Lien Vu2016-12-31T10:01:32Z2017-01-13T02:28:30Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2202This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22022016-12-31T10:01:32ZExtremum Seeking Control based MPPT for photovoltaic array under uniform and non-uniform irradiancesIn order to extract the maximum power from photovoltaic (PV) array, the maximum power point tracking (MPPT) technology has always been applied in PV systems. The Perturb and Observe (P&O) and Incremental Conductance (INC) methods are the most popular and widely used under the constant irradiance. However, the changes of the environmental parameters, such as cloud cover or the building block, will lead to the radiation change and then have a direct effect on the location of Maximum Power Point (MPP). In order to carry out MPPT in PV array under Partial Shading Conditions (PSCs), a method based on Extremum Seeking Control (ESC) is applied to determine the optimal value of a reference current in the PV system. The proposed ESC approach for the Global Maximum Power Point Tracking (GMPPT) in this work uses a series combination of a High Pass Filter (HPF) and two Low Pass Filters (LPFs). These three filters act as two Band Pass Filters (BPFs) and let a specific frequency of input power which includes the derivative of PV with respect to its voltage pass through. This auto-tuning strategy was developed to maximize the PV array output power through the regulation of the voltage input to the DC-DC boost converter in order to lead the PV array steady-state to a stable oscillation behavior around the Global Maximum Power Point (GMPP). The performance of the proposed ESC algorithm is evaluated by comparing it with the conventional ESC and modified P&O method in terms of tracking speed and accuracy by utilizing MATLAB SIMULINK. The simulation results demonstrate that the tracking capability of the proposed ESC algorithm is superior to that of the conventional ESC and modified P&O algorithm, particularly under low radiance and sudden mutation irradiance conditions.
Key Words: Boost converter; Extremum Seeking Control; Maximum Power Point Tracking (MPPT); Partial Shading Conditions (PSCs); Photovoltaic (PV) system.Van Manh Hoangmanhhv87@vnu.edu.vnNgoc Viet Nguyenvietnn.mt@gmail.comManh Thang Phamthangpm@vnu.edu.vn2016-12-31T09:56:50Z2016-12-31T09:56:50Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2367This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23672016-12-31T09:56:50ZModeling an Testing of a Two-buoy Heaving Wave Energy ConverterA design of a two-buoy small scale point absorber was built and tested in July 2016 on West Lake. The tests were aimed at performance characterization and validation of a linear dynamics model. The coefficients used in the model are obtained through a combination of bench-top and tank-side experiment. The device produced an average of 40W from waves of 35 cm height and frequencies between 0.6-0.8Hz. The experimental results compare reasonably well with the numerical model. However, there is a significant amount of scatter in the experimental values which was attributed to various sourcesVan Ngoc PhungThe Ba Dangbadt@vnu.edu.vnVan Duc Nguyen2016-12-30T08:26:32Z2016-12-30T08:26:32Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2373This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23732016-12-30T08:26:32ZA new viral marketing strategy with the competition in the large-scale Online Social NetworksThe problem of Influence Maximization (IM) on social networks proposed firstly by Kempe et al. (2003) has been researched and developed with many cases. However, the IM in limited time while unwanted users are restricted is still a new potential subject. In this paper, we conducted research the problem on the model of information diffusion name Locally Bounded Diffusion and tested some useful heuristic algorithms. The results of the experiment on some real datasets of social networks show that the algorithm meta-heuristic generated better output than the others.Van Canh PhamKim Dung HaQuang Dung NgoQuang Cao VuXuan Huan Hoang2016-12-30T08:26:04Z2016-12-30T08:26:04Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2366This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23662016-12-30T08:26:04ZMột thuật toán hiệu quả dựa trên giải thuật tối ưu đàn
kiến giải bài toán r|p trung tâmDuc Quang VuXuan Huan HoangThanh Mai Do2016-12-30T02:21:30Z2016-12-30T02:21:30Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2379This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23792016-12-30T02:21:30ZVerifying OSEK/VDX OS Design using Its Formal SpecificationAutomotive systems are widely used in industry and our daily
life. As the reliability of automotive systems is becoming a greater
challenge in our community, increasingly more automotive companies are
interested in applying formal methods to improve the reliability of
automotive systems. We focus on automotive operating systems
conforming to the OSEK/VDX standard. Such operating systems are considered as important
components to ensure the reliability of the automotive systems. In
previous work, we proposed a framework to verify the design models of
reactive systems against their specifications. This framework allows us to
check whether the design model conforms to the specification based
on a simulation relation. This paper shows a case study in which the
framework is applied to a real design of the OSEK/VDX operating system. As a
result, we found that we were able to check several important properties
of the design model. We show the effectiveness and practicality of the framework based on the results of the case study.Dieu Huong Vuhuongvd@vnu.edu.vnYuki ChibaKenro YatakeToshiaki Aoki2016-12-29T12:52:51Z2017-01-12T16:10:17Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2354This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23542016-12-29T12:52:51ZA Novel Behavior-based Navigation Architecture of Mobile Robot in Unknown EnvironmentsThis study proposes behavior-based navigation architecture, named BBFM, for mobile robot in unknown environment with obstacles. The architecture is carried out in three steps: (i) analyzing the navigation problem to determine parameters of the architecture; (ii) designing the objective functions to relate input data with the desired output; and (iii) fusing the output of each objective function to generate the optimal control signal. We use fuzzy logic to design the objective functions and multi-objective optimization to find the Pareto optimal solution for the fusion. A number of simulations, comparisons, and experiments were conducted. The results show that the proposed architecture outperforms some popular behavior- based architectures in navigating the mobile robot in complex environments.Thi Thanh Van Nguyenvanntt@vnu.edu.vnManh Duong Phungduongpm@vnu.edu.vnAnh Viet Dangvietda@vnu.edu.vnQuang Vinh Tranvinhtq@vnu.edu.vn2016-12-29T12:50:43Z2016-12-29T12:50:43Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2314This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23142016-12-29T12:50:43ZPiezo-resistive and thermo-resistance effects of highly-aligned CNT based macrostructuresThanh Van Daudauv@sc.sumitomo-chem.co.jpCanh-Dung TranCanh-Dung.Tran@usq.edu.auThanh Tung Buitungbt@vnu.edu.vnV. D. X. NguyenVDXNguyen@gmail.comXuan Thien Dinhthien@cfd.ritsumei.ac.jp2016-12-29T12:13:36Z2016-12-29T12:13:36Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2372This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23722016-12-29T12:13:36ZTime-Critical Viral Marketing Strategy with the Competition on Online Social NetworksVan Canh PhamTra My ThaiKim Dung HaQuang Dung NgoXuan Huan Hoanghuanhx@vnu.edu.vn2016-12-29T12:10:53Z2016-12-29T12:10:53Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2198This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21982016-12-29T12:10:53ZResearch, Design and Fabrication of 2.45 GHz Microstrip Patch Antenna Arrays for Close-Range Wireless Power Transmission SystemsAntennas play a very important role in wireless
power transmission (WPT) systems using microwave since they
affect the system transmission efficiency. General requirements
for an antenna used for WPT systems are high directivity and
narrow beamwidth. This paper presents the design, simulation
and fabrication of microstrip patch antenna arrays for closerange
WPT systems. Various antenna prototypes such as single
patch, 2�2, 2�4, 4�8 and 8�8 microstrip patch antenna arrays
working at 2.45 GHz are proposed. The 2�4 microstrip
patch antenna array is fabricated and measured using Anritsu
37364D Vector Network Analyzer and NSI 2000 Nearfield System.
Measurement results show that the fabricated antenna obtains a
directivity of 14.7 dBi and a 3 dB beamwidth of 23.2 degree. The
experiment with the WPT system is carried out. This paper also
presents structure of a WPT system and the role each building
block in the system.
Index Terms—Wireless Power Transmission, Rectenna, Microstrip
Patch, Antenna Array, Microwave EngineeringHoang Giang Bachgiangbh@vnpt-hanoi.com.vnVan Giap Nguyengiapnv_57@vnu.edu.vnPhuong Linh TaTuan Anh Vutanhvu@vnu.edu.vnGia Duong Bachduongbg@vnu.edu.vn2016-12-29T12:09:15Z2016-12-29T12:09:15Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2172This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21722016-12-29T12:09:15ZDesign of a Front-End for Satellite ReceiverThis paper focuses on the design and implementation of a front-end for a Vinasat satellite receiver with auto-searching mechanism and auto-tracking satellite. The front-end consists of a C-band low-noise block down-converter and a L-band receiver. The receiver is designed to meet the requirements about wide-band, high sensitivity, large dynamic range, low noise figure. To reduce noise figure and increase bandwidth, the C-band low-noise amplifier is designed using T-type of matching network with negative feedback and the L-band LNA is designed using cascoded techniques. The local oscillator uses a voltage controlled oscillator combine phase locked loop to reduce the phase noise and select channels. The front-end has successfully been designed and fabricated with parameters: Input frequency is C-band; sensitivity is greater than -130 dBm for C-band receiver and is greater than -110dBm for L-band receiver; output signals are AM/FM demodulation, I/Q demodulation, baseband signals.Van Hoi Trantranvanhoi@vov.org.vnThi Lanh Ngongothilanh@vov.org.vnXuan Truong Nguyennguyenxuantruong@vov.org.vnHuu Duc Nguyenducnh@vnu.edu.vnDuong Bach Giaduongbg@vnu.edu.vn2016-12-29T08:27:04Z2016-12-29T08:27:04Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2371This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23712016-12-29T08:27:04ZACOGNA: An Efficient Method for Protein-Protein Interaction Network AlignmentProtein–protein interaction network alignment enables us to identify orthologous proteins, predict protein functions and build evolutionary relationships of species. This article introduces an algorithm for global alignment of protein- protein interaction network based on ant colony optimization (ACO) method. The experimental results offer outstanding advantages of the proposed algorithms.Ngoc Ha TranXuan-Huan Hoanghuanhx@vnu.edu.vn2016-12-29T08:26:40Z2016-12-29T08:26:40Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2369This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23692016-12-29T08:26:40ZAn Improved Artificial Immune Network For Solving Construction Site Layout OptimizationNature-inspired algorithms are often used to find optimal solutions for many combinatorial problems. An immune inspired algorithm, opt-aiNet algorithm, is well known for func- tion optimization. In this paper, we develop a combination of local search with opt-aiNet, called lopt-aiNet, to solve construction site layout (CSL) problem. The effectiveness of the proposed algorithm is investigated through experiments on some datasets taken from the state-of-art and a randomly created dataset. Ex- perimental results show that the lopt-aiNet can produce optimal transportation cost with lower run time compared to the site layouts generated by metaheuristics: Genetic Algorithm (GA), Particle Swarm Optimization (PSO), Ant Colony Optimization (ACO) and aiNet.Duc Quang VuVan Truong NguyenXuan-Huan Hoanghuanhx@vnu.edu.vn2016-12-29T08:24:36Z2016-12-29T08:24:36Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2362This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23622016-12-29T08:24:36ZPhát triển công cụ dịch ngược firmware trên thiết bị định tuyếnVạn vật kết nối (Internet of Things) hiện nay được sử dụng ngày càng rộng rãi trong cuộc sống, đi kèm với những tiện ích mới công nghệ này mang lại đó chính là vấn đề an ninh, an toàn thông tin. Kết quả các nghiên cứu gần đây đã chỉ ra rằng các lỗ hổng bảo mật và đặc biệt là mã độc xuất hiện rất nhiều trên hệ điều hành của các thiết bị mạng (firmware). Vì tính đặc thù cao của các thiết bị mạng cũng như của các firmware mà việc phân tích, rà quét các lổ hổng bảo mật và mã độc gặp rất nhiều trở ngại. Hơn nữa, do chưa có được sự quan tâm đúng mức của cá nhân, tổ chức lớn nên việc phát triển các công cụ cũng như phương pháp phân tích, phát hiện còn nhiều hạn chế. Hạn chế có thể kể đến là khả năng trích chọn firmware và dịch ngược chúng thành mã tường minh để từ đó có thể sử dụng các phương pháp phân tích lỗ hổng, mã độc khác nhau. Trong bài báo này, C500-Toolkit sẽ được giới thiệu với mục tiêu tăng hiệu suất trích chọn và dịch ngược firmware của các thiết bị định tuyến. Gần 13.674 firmware từ 27 nhà phân phối được sử dụng để đánh giá và so sánh với các công cụ hiện có như fmk, binwalk và mô đun trích chọn, dịch ngược của firmadyne.Nghi Phu Trantnphvan@gmail.comHuy Trung NguyenQuoc Dung NgoNgoc Binh Nguyennnbinh@vnu.edu.vnDai Tho Nguyennguyendaitho@vnu.edu.vn2016-12-29T08:24:16Z2017-01-12T16:15:40Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2361This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23612016-12-29T08:24:16ZPOCAD: a Novel Payload-based One-Class Classifier for Anomaly DetectionIn this paper, we propose a novel Payload-based One-class Classifier for Anomaly Detection called POCAD, which combines a generalized 2v-gram feature extractor and a one-class SVM classifier to effectively detect network intrusion attacks. We extensively evaluate POCAD with real-world datasets of HTTP-based attacks. Our experiment results show that POCAD can quickly detect malicious payload and achieves a high detection rate as well as a low false positive rate. The experiment results also show that POCAD outperforms state of the art payload-based detection schemes such as McPAD [8] and PAYL [5].Xuan Nam Nguyennamnx228@gmail.comDai Tho Nguyennguyendaitho@vnu.edu.vnHai Long Vulhvu@us.ibm.com2016-12-29T08:22:47Z2016-12-29T08:22:47Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2355This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23552016-12-29T08:22:47ZA new phylogenetic tree sampling method for maximum parsimony bootstrapping and proof-of-concept implementationReconstructing maximum parsimony (MP) trees along with bootstrap for large multiple sequence alignments is a computationally challenging task. In this paper, we present MPBoot, a new method for approximating MP bootstrap based on the idea of a previously introduced method for maximum likelihood bootstrap. MPBoot economizes the computations by only sampling trees on the original alignment and simultaneously calculating exact parsimony scores for all bootstrap alignments. Preliminary experiments on simulated data showed that MPBoot is about 2-3.5 times faster and yields better parsimony scores than a fast bootstrap procedure implemented in TNT. MPBoot also produced less biased support value than TNT for small simulated data sets (<;= 200 sequences). However, for large number of sequences (>=500) MPBoot overestimates the probability that a clade is true, i.e., results in likely high false positive rates. As MPBoot is currently a proof-of-concept implementation, more work is to understand the limitations of the method.Thi Diep Hoangdiepht@vnu.edu.vnLe Sy VinhTomas FlouriAlexandros StamatakisArndt von HaeselerBui Quang Minh2016-12-29T02:49:05Z2016-12-29T02:49:05Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2321This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23212016-12-29T02:49:05ZLow Residual Stress in Si Substrate of Annular-Trench-Isolated TSVDriven by the need of reduced energy consumption in devices, 3D integration technology by through silicon via (TSV) attracts increasing interests. However, high thermal stress is induced by the large mismatch of the coefficient of thermal expansion (CTE) among the different materials in TSV. The thermal stress is a serious reliability concern for TSV in 3D integration system. In order to solve the stress issues in 3D packaging technology with TSV, we proposed a structure as annular-trench-isolated (ATI) TSV with an extra Si ring between Cu core and SiO2 layer. In this paper, we presented the fabrication process of ATI TSV with two separate etching processes for the parylene-HT trench and solder core while remaining a Si ring between parylene-HT layer and solder core. Note that the trench is narrow with thickness of 2 ¿¿m, and its aspect ratio (AR) is high as 7. We successfully deposited the insulator of parylene-HT material in the whole annular trench between Si substrate and Si ring. And the uniformity of deposited parylene-HT layer was observed clearly by 3D X-ray computed tomography method as CT scan. Considering the high aspect ratio of our TSV, difficulty was expected during the conventional process, such as barrier deposition and Cu electroplating. Therefore, solder injection was implemented for depositing the material into the vias of ATI TSV. In order to understand the stress level after fabrication process, the residual stress was investigated with validated simulation model. A lower residual stress in Si substrate was observed in ATI TSV than that of regular TSV due to less solder volume and the redistribution of stress by Si ring in ATI TSV. During thermal cycling, the stress level increased with temperature decreasing from 125¿¿C to -40¿¿C for both ATI and regular TSV. The residual stress measurement of ATI TSV will be performed in further work.Wei Fengwei.feng@aist.go.jpThanh Tung Buitungbt@vnu.edu.vnNaoya Watanabenaoya-watanabe@aist.go.jpMasahiro Aoyagim-aoyagi@aist.go.jpKatsuya Kikuchik-kikuchi@aist.go.jp2016-12-29T02:48:51Z2016-12-29T02:48:51Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2319This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23192016-12-29T02:48:51ZIntegration of a microfluidic chip with multiplexed optical fluorescence detector through anisotropic etching of Si using Tetramethylammonium hydroxide (TMAH)Point of care testing (POCT) systems, are widely used to firstly, diagnose and secondly, monitor a number of illnesses and infectious diseases. This research aims to develop the integration between an optical fluorescence system and a microfluidic chip - through the use of advanced manufacturing techniques, such as anisotropic wet etching of Silicon (Si) wafers. The fabricated Si microfluidic chips may integrate into an existing POCT system and provide a potential avenue into multiplexed detection. Zemax and OptiCAD simulation packages were used to confirm the validity of the integrated microfluidic chip design. A testable microfluidic chip, using anisotropic wet etching of a Si wafer by Tetramethylammonium hydroxide (TMAH) etching solution, was fabricated. The process used a mask-less photoresist design, allowing for an easier and cost effective developmental stage in order to provide a proof of concept design. Currently, the TMAH etching process provides the required 370µm etch depth, to house a micro-capillary.Hannah Robbinsh.r.robbins@outlook.comChangqing Liuc.liu@lboro.ac.ukSijung Hus.hu@lboro.ac.ukThanh Tung Buitungbt@vnu.edu.vnMasahiro Aoyagim-aoyagi@aist.go.jp2016-12-28T14:56:03Z2016-12-28T14:56:03Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2318This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23182016-12-28T14:56:03ZBiological microparticles detection based on differential capacitive sensing and dielectrophoresis manipulationThe manipulation and detection of living cells are essential requirements for many applications in biology, biotecnology and medicine. In this study, we propose a microfluidic device, which facilitated of a differential capacitively coupled contactless conductively detection (DC4D) coplanar capacitor structure and a dielectrophoresis (DEP) concentrator based on circular electrodes for detecting of living cells. With the proposed device, first, the target and non-target cells are guided toward the center of the working chamber due to the dielectrophoresis forces. Then the target cells are captured by the electrode covered with aptamers, which possess a high affinity to the target cells. After being flushed to wash away the non-target cells in the working chamber, the differential capacitance is read to identify the presence of target cells. Numerical simulations of the DEP manipulation and DC4D were performed to proof the concept of the proposed design. A prototype of the proposed device was fabricated using micromachining technology. Manipulation and sensing performances of the device were investigated. The evaluation results show that the capacitance output changes up to 3fF corresponding to the presence of about twenty-five cells captured at the electrode.T. T. H. TranN. V. NguyenN.C. NguyenThanh Tung Buitungbt@vnu.edu.vnDuc Trinh Chutrinhcd@vnu.edu.vn2016-12-28T14:40:04Z2016-12-28T14:40:04Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2326This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23262016-12-28T14:40:04ZA Prospective Low-k Insulator for Via-Last through-Silicon-Vias (TSVs) in 3D IntegrationThanh Tung Buitungbt@vnu.edu.vnXiaojin ChengNaoya WatanabeFumiki KatoKatsuya KikuchiMasahiro Aoyagi2016-12-28T14:37:37Z2016-12-28T14:37:37Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2330This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23302016-12-28T14:37:37ZHyper-volume Evolutionary AlgorithmWe propose a multi-objective evolutionary algorithm (MOEA), named the Hyper-volume Evolutionary Algorithm (HVEA). The algorithm is characterised by three components. First, individual fitness evaluation depends on the current Pareto front, specifically on the ratio of its dominated hyper-volume to the current Pareto front hyper-volume, hence giving an indication of how close the individual is to the current Pareto front. Second, a ranking strategy classifies individuals based on their fitness instead of Pareto dominance, individuals within the same rank are non guaranteed to be mutually non-dominated. Third, a crowding assignment mechanism that adapts according to the individual's neighbouring area, controlled by the neighbouring area radius parameter, and the archive of non-dominated solutions. We perform extensive experiments on the multiple 0/1 knapsack problem using different greedy repair methods to compare the performance of HVEA to other MOEAs including NSGA2, SEAMO2, SPEA2, IBEA and MOEA/D. This paper shows that by tuning the neighbouring area radius parameter, the performance of the proposed HVEA can be pushed towards better convergence, diversity or coverage and this could be beneficial to different types of problems.Nguyen Khoi Lekhoi.n.le@vnu.edu.vnDario Landa-Silva2016-12-28T09:45:04Z2016-12-28T09:45:04Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2261This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22612016-12-28T09:45:04ZOptimizing the Shortest Path Query on Large-Scale Dynamic Directed GraphPhuong Hanh Duhanhdp@vnu.edu.vnHai Dang Phamdangph@vnu.edu.vnNgoc Hoa Nguyenhoa.nguyen@vnu.edu.vn2016-12-27T07:27:52Z2016-12-27T07:27:52Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2268This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22682016-12-27T07:27:52ZDNA-magnetic bead detection using disposable cards and the anisotropic magnetoresistive sensorA disposable card incorporating specific DNA probes targeting the 16 S rRNA gene of
Streptococcus suis was developed for magnetically labeled target DNA detection. A singlestranded
target DNA was hybridized with the DNA probe on the SPA/APTES/PDMS/Si asprepared
card, which was subsequently magnetically labeled with superparamagnetic beads for
detection using an anisotropic magnetoresistive (AMR) sensor. An almost linear response
between the output signal of the AMR sensor and amount of single-stranded target DNA varied
from 4.5 to 18 pmol was identified. From the sensor output signal response towards the mass of magnetic beads which were directly immobilized on the disposable card surface, the limit of detection was estimated about 312 ng ferrites, which corresponds to 3.8 μemu. In comparison with DNA detection by conventional biosensor based on magnetic bead labeling, disposable cards are featured with higher efficiency and performances, ease of use and less running cost with respects to consumables for biosensor in biomedical analysis systems operating with immobilized bioreceptorThi Hien Lelehien@vnu.edu.vnKhanh Quynh LeThi Huyen VuDinh Tu Buibuidinhtu@vnu.edu.vnPhuong DMNhung PHThi Huong Giang Dogiangdth@vnu.edu.vnHuu Duc Nguyenducnh@vnu.edu.vn2016-12-27T07:17:29Z2016-12-27T07:17:29Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2306This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/23062016-12-27T07:17:29ZUnderwater sound propagation in Tokin Gulf and its applications for communicationUnderwater sound propagation (USP) is a complicated problem since in almost cases we do not have enough knowledge (both in theory and experiments) on required parameters for long range channel estimations. In USP problem we must consider features of ocean surface, bottom as well as water column properties. Those quantities are varying in space whereas oceanographic quantities changing in time. This paper solve USP problem in Tonkin gulf in winter using wave propagation theory. From that it is defined the impulse response (IR) and the distribution of the underwater sound channel (USC) in Tonkin gulf. Some results using proposed USC combining space modulation(SM) are shown.Cao Quyen Tranquyentc@vnu.edu.vnVan Nui Nguyen2016-12-25T17:09:51Z2016-12-25T17:09:51Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2173This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21732016-12-25T17:09:51ZDesign and Fabrication of Rectifying Antenna Circuit for
Wireless Power Transmission System Operating at ISM BandThis paper introduces an overview of a rectifying antenna (rectenna) circuit topology for microwave power transmission system. Specially, a rectenna
based on a microstrip patch antenna and a microwave double voltage rectifier
at 2.45GHz were designed and fabricated. The antenna’s return loss is
achieved of -15 dB at 2.45GHz. The microwave to DC conversion efficiency
of the rectenna was measured as 71.5% with 22 dBm input power and 810
load. The design and simulated results were carried out by the microwave
engineering professional design software, known as ADS2009 package. All
design and simulation results will be reported.Chuc Doan Huuchucdh@hpu.edu.vnDuong Bach Giaduongbg@vnu.edu.vn2016-12-25T17:08:37Z2017-01-12T16:00:38Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2168This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21682016-12-25T17:08:37ZMáy phát tín hiệu dải rộng cho radar thế hệ mớiBằng độc qyền Giải pháp hữu ích về giải pháp công nghệ chế tạo máy phát radar, làm việc trên dải sóng UHF, phát tín hiệu điều chế mã pha manip trong xung. Công suất phát lên tới 10 KW xung độ rộng 220 micro giây trên chu kỳ lập lại xung 1 mili giây.Gia Duong Bachduongbg@vnu.edu.vn2016-12-25T17:08:15Z2017-01-12T16:07:46Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2167This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21672016-12-25T17:08:15ZMáy phát tín hiệu mã kiểm soát không lưuBằng độc quyền Giải pháp hữu ích mô tả Giải pháp công nghệ cho thiết kế chế tạo máy phát tín hiệu dải rộng công suất lớn, làm việc trên băng tần L. Công suất lớn được hình thành nhờ phương pháp cộng đồng pha đồng biên độ dùng cầu Wilkinson từ các mô đun cơ sở.Gia Duong Bachduongbg@vnu.edu.vn2016-12-25T16:58:09Z2016-12-25T16:58:09Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2170This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21702016-12-25T16:58:09ZEstimation of elasticity and viscosity in heterogeneous medium using FDTD method and AHI algorithmMechanical properties of tissues in terms of elasticity and viscosity provide us useful information which may be used in detecting tumors. These parameters can be estimated from the measurement of particle velocities of shear wave propagation which is generated by a vibrating needle at a certain frequency. For the heterogeneous medium, the finite difference time domain (FDTD) is an effective method to present the shear wave propagation. The elasticity and viscosity are then estimated using the algebraic Helmholtz inversion (AHI) algorithm. However, there is a lack of deep investigation of estimation by combining FDTD method and AHI algorithm. Thus, this paper presents a complete system which includes the principle of excitation and measurement, the FDTD to model the shear wave propagation, the AHI algorithm to estimate the elasticity and viscosity, and the investigation on frequency-dependent the elasticity and viscosity. Also, we suggest that the excitation frequency of 200 Hz will offer the best estimation of the elasticity and viscosity.Hai Luong Quangluonghai@gmail.comTan Tran Ductantd@vnu.edu.vnTrung Nguyen Linhlinhtrung@vnu.edu.vnTue Huynh Huuhhtue@hcmui.edu.vn2016-12-25T16:57:50Z2016-12-25T16:57:50Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2169This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21692016-12-25T16:57:50ZOn the implementation of chaotic compressed sensing for MRIWe consider the application of Compressed Sensing (CS) to enhance the acquisition speed in Magnetic Resonance Imaging (MRI). For CS-based MRI, random sampling is often implemented in the k-space and depends on the uniform distribution and energy distribution of MRI images in the k-space. In contrast, we propose a new deterministic sampling method for CS-based MRI using the logistic map, which has good statistical properties and can be easily converted to uniform-like chaotic sequences. Simulation results confirmed that the proposed method is equivalent to state-of-the-art methods in terms of the relative root-mean-square error and the probability of exact reconstruction.Truong Minh-Chinhtmchinh@gmail.comtrung nguyen linhlinhtrung@gmail.comTan Tran Ductantd@vnu.edu.vn2016-12-25T16:57:09Z2016-12-25T16:57:09Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2192This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21922016-12-25T16:57:09ZFast adaptive PARAFAC decomposition algorithm with linear complexityWe present a fast adaptive PARAFAC decomposition algorithm with low computational complexity. The proposed algorithm generalizes the Orthonormal Projection Approximation Subspace Tracking (OPAST) approach for tracking a class of third-order tensors which have one dimension growing with time. It has linear complexity, good convergence rate and good estimation accuracy. To deal with large-scale problems, a parallel implementation can be applied to reduce both computational complexity and storage. We illustrate the effectiveness of our algorithm in comparison with the state-of-the-art algorithms through simulation experiments.Viet Dung Nguyennvdung1987@gmail.comKarim Abed-Meraimkarim.abed-meraim@univ-orleans.frLinh Trung Nguyenlinhtrung@vnu.edu.vn2016-12-25T16:55:18Z2016-12-25T16:55:18Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2187This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21872016-12-25T16:55:18ZAn efficient example-based method for CT image denoising based on frequency decomposition and sparse representationIn this paper we present an effective example-based method for Gaussian denoising of CT images. In the proposed method, an image is considered as a sum of the three frequency bands: low-band, middle-band and high-band. We assume that the noise component is often mixed into the middle-band and the high-band and thus in order to better preserve the high-frequency details in the image we perform denoising on these two bands. The proposed denoising method is based on a sparse representation model in which a set of standard images is used to construct the example dictionaries. The experimental results demonstrate that the proposed method can preserved very good the high-frequency details. The objective and subjective comparisons also show that our method outperforms other state-of-the-art denoising methods.Thanh Trung Nguyentrungntktmt@gmail.comDinh Hoan Trinhhoantd@gmail.comLinh Trung Nguyenlinhtrung@vnu.edu.vn2016-12-25T16:53:55Z2016-12-25T16:53:55Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2193This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21932016-12-25T16:53:55ZNew robust algorithms for sparse non-negative three-way tensor decompositionsTensor decomposition is an important tool for many applications in diverse disciplines such as signal processing, chemometrics, numerical linear algebra and data mining. In this work, we focus on PARAFAC and Tucker decompositions of three-way tensors with non-negativity and/or sparseness constraints. By using an all-at-once optimization approach, we propose two decomposition algorithms which are robust to tensor order over-estimation errors, – a desired practical property when the tensor rank is unknown. Different algorithm versions are proposed depending on the desired constraint (or property) of the tensor factors or the core tensor. Finally, the performance of the algorithms are assessed via insightful simulation experiments on both simulated and real-life data.Viet Dung NguyenKarim Abed-MeraimLinh Trung Nguyen2016-12-23T06:38:01Z2016-12-23T06:38:01Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2273This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22732016-12-23T06:38:01ZUtilizing Adaptive Dynamic Taylor Kriging Assisted Multi- Objective DE Algorithm for Optimization Design of Electromagnetic DeviceBin XiaMinh Trien Phamtrienpm@vnu.edu.vnGil-Gyun JeongChang Seop Koh2016-12-23T04:08:01Z2016-12-23T04:09:38Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2289This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22892016-12-23T04:08:01ZThe nonlinear stability of axisymmetric functionally graded material annular spherical shells under thermo-mechanical loadThi Thuy Anh Vuanhvutt@vnu.edu.vnDinh Duc Nguyenducnd@vnu.edu.vn2016-12-23T04:05:36Z2016-12-23T04:05:36Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2293This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22932016-12-23T04:05:36ZSpeech act classification in Vietnamese Utterance and its application in smart mobile voice interactionThi Lan NgoQuang Vu Duongvudq_57@vnu.edu.vnSon Bao Phamsonpb@vnu.edu.vnXuan Hieu Phanhieupx@vnu.edu.vn2016-12-23T04:01:22Z2016-12-23T04:01:22Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2292This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22922016-12-23T04:01:22ZDomain identification for intention posts on online social mediaThai Le LuongQuoc Tuan TruongHai Trieu DangXuan Hieu Phanhieupx@vnu.edu.vn2016-12-19T16:50:18Z2016-12-19T16:50:18Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2276This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22762016-12-19T16:50:18ZSwarm Optimization Approach for Light Source Detection by Multi-robot SystemExploration and searching in unknown or hazardous environments using multi-robot systems (MRS) is among the principal topics in robotics. There have been numerous works on searching and detection of odor, fire or pollution sources. In this paper, a modified Particle Swarm Optimization Algorithm (PSO) was presented for MRS on detecting light sources, namely APSO. In the proposed algorithm, an integration of conventional PSO and Artificial Potential Field (APF) is employed to use swarm intelligence for space exploration and light source detection. The formulas for APSO velocities are based on those of PSO and APF. Furthermore, each particle is surrounded by an APF that forms repulsive force to prevent collision while the swarm is in operation. The simulation results of APSO in Matlab by various scenarios confirmed the reliability and efficiency of the proposed algorithm.Anh Quy Hoangquyha@vnu.edu.vnMinh Trien Phamtrienpm@vnu.edu.vn2016-12-19T16:49:20Z2016-12-19T16:49:20Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2277This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22772016-12-19T16:49:20ZDesign and Implementation of a Multi-Robot System Based on Zigbee NetworkMulti-robot system is widely used for collecting environmental data, patrolling in factories or boundaries, searching and rescuing. In this paper, a multi-robot system (MRS) was designed and implemented. The robots in this system communicate over a Zigbee network. This MRS is capable of avoiding collision; detecting light sources; getting information on temperature and humidity in its work space, as well as the position of each robot using GPS antennas. The collected data are sent to and stored in a server for further analysing and predicting environment condition. The MRS could be used in monitoring factories. A prototype system consisting of three mobile robots was developed and it has successfully detected light source in laboratory condition.Van Nam Trannamtv_57@vnu.edu.vnAnh Quy Hoangquyha@vnu.edu.vnMinh Trien Phamtrienpm@vnu.edu.vn2016-12-19T02:33:03Z2016-12-19T02:33:03Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2250This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22502016-12-19T02:33:03ZNâng cao thuật toán đối sánh mã trụ MCCVân tay là đặc trưng sinh trắc học được sử dụng phổ biến rộng rãi trong các ứng dụng dân sự cũng như pháp lý. Hiện nay các kết quả nghiên cứu đạt được các kết quả tương đối tốt về độ chính xác và tốc độ xử lý, nhưng nhu cầu về các hệ thống nhận dạng nhanh, chính xác, đặc biệt trên các CSDL lớn hàng triệu vân tay vẫn là bài toán nhận được nhiều quan tâm nghiên cứu hiện nay. Trong bài báo này, chúng tôi khảo sát tổng quan về một số thuật toán đối sánh vân tay hiện tại, chú trọng đến phương pháp đối sánh dựa trên mã trục các điểm trạc MCC. Từ đó, chúng tôi đã đề xuất kỹ thuật cải tiến MCC dựa trên bước gia cố. Kỹ thuật này đã được tiến hành thực nghiệm trên bộ CSDL vân tay chuẩn FVC 2002. Kết quả đánh giá chúng tôi thu được có cả ba độ đo EER, FMR100, FMR1000 chính xác hơn so với giải thuật MCC chuẩn trong khi tốc độ so khớp gần như được giữ nguyên.Hong Hai LeNgoc Hoa Nguyenhoa.nguyen@vnu.edu.vn2016-12-17T16:20:23Z2016-12-17T16:21:58Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2188This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21882016-12-17T16:20:23ZAdaptive PARAFAC decomposition for third-order tensor completionThis paper proposed a tensor completion algorithm by tracking the Parallel Factor (PARAFAC) decomposition of incomplete third-order tensors with one dimension growing with time. The proposed algorithm first tracks a low-dimensional subspace, then updates the loading matrices of the PARAFAC decomposition. Simulation results showed that the algorithm is reliable and fast, in comparison to the state-of-the-art PARAFAC Weighted OPTimization algorithm.Minh Chinh TruongViet Dung NguyenLinh Trung Nguyenlinhtrung@vnu.edu.vnKarim Abed-Meraim2016-12-17T16:18:24Z2016-12-17T16:19:56Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2174This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21742016-12-17T16:18:24ZDesign of aC-Band Low-Noise Block Front-end for Satellite ReceiversThis paper describes the study, design and fabrication of a C-band low-noise block front-end for satellite receivers. The front-end consists of a low-noise amplifier, two band pass filters in C-band and L-band, a down-converter and an intermediate frequency amplifier. To reduce noise figure and increase bandwidth, the low-noise amplifier was designed using T-type of matching network with negative feedback. The down-converter used a voltage controlled oscillator with phase locked loop to reduce the phase noise. The front-end converts input signals from C-band (3.4 GHz-4.2 GHz) to the L-band (950 MHz-1750 MHz). The low-noise block has successfully been designed and fabricated with parameters: Overall gain is greater than 60 dB; the noise figure is less than 1dB; phase noise of local oscillator obtains-107.57dBc/Hz at 50KHz.Hoi Tran VanTruong Nguyen XuanLanh Ngo ThiGia Duong Bachduongbg@vnu.edu.vn2016-12-16T08:22:27Z2016-12-16T08:22:27Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2061This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20612016-12-16T08:22:27ZA Technique for Generating Test Data using Genetic AlgorithmThi Ngoc DinhDinh Hieu Vohieuvd@vnu.edu.vnViet Ha Nguyenhanv@vnu.edu.vn2016-12-16T08:18:22Z2016-12-16T08:18:22Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2034This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20342016-12-16T08:18:22ZPre-rendered subtitles removal in video sequences using text detection and inpaintingTung Long VuongDinh Minh Leminhld_57@vnu.edu.vnThi Thuy LeThanh Ha Leltha@vnu.edu.vn2016-12-16T05:16:53Z2016-12-16T05:16:53Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2254This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22542016-12-16T05:16:53ZA robust transformation-based learning approach using ripple down rules for part-of-speech taggingQuoc Dat NguyenQuoc Dai NguyenDuc Dang PhamBao Son Phamsonpb@vnu.edu.vn2016-12-16T05:13:10Z2016-12-16T05:13:10Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2257This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22572016-12-16T05:13:10ZUsing Content-Based Features for Author Profiling of Vietnamese Forum PostsThis paper reports the results of author profiling task for Vietnamese forum posts to identify the personal traits, such as gender, age, occupation, and location of the author using content-based features. Experiments were conducted on the different types of features, including stylometric features (such as lexical, syntactic, structural features) as well as content-based features (the most important words) to compare the performance and on the data sets we collected from the various forums in Vietnamese. Three learning methods, consisting of Decision Tree, Bayes Network, Support Vector Machine (SVM), were tested and the SVM achieved the best results. The results show that these kinds of features work well on such a kind of short and free style messages as forum posts, in which, content-based features yielded much better results than stylometric features.Tran Duc DuongBao Son Phamsonpb@vnu.edu.vnHanh Tan2016-12-16T05:04:12Z2017-12-07T09:54:05Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2258This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22582016-12-16T05:04:12ZCustomer gender prediction based on E-commerce dataDuc Duong TranHanh TanSon Bao Phamsonpb@vnu.edu.vn2016-12-14T10:36:15Z2016-12-14T10:36:15Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2038This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20382016-12-14T10:36:15ZSingle Camera Based Fall Detection Using Motion and Human Shape FeaturesViet Anh Nguyenvietanh@vnu.edu.vnThanh Ha Leltha@vnu.edu.vnThi Thuy Nguyen2016-12-14T10:32:26Z2016-12-14T10:32:26Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2028This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20282016-12-14T10:32:26ZKinect based character navigation in VR GameThi Chau Machaumt@vnu.edu.vnMinh Duong Hoang2016-12-14T10:31:28Z2016-12-14T10:31:28Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2224This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22242016-12-14T10:31:28ZTarget tracking solution for multi-sensor data fusion in wireless sensor networksWireless sensor networks are often composed of many sensor nodes, they are powered by batteries with limited
capacity . The sensor nodes are randomly scattered within in the ranger monitoring and send – receiver data using
radio waves. Many research projects had demonstrated the consumption of battery power by the data transceiver
occupy large compared to the calculation on the sensor node. In this paper, we propose energy saving solutions
of nodes in a cluster by only choosing some nodes in the cluster to track the target and transmit this data to
cluster head nodes. We based on the location of the sensor nodes in the cluster compare with the location of
target and cluster head nodes to perform this selection. The effectiveness of the proposed solutions will be
evaluated based on the number of sensor nodes are selected considering the number of nodes in the cluster, this
is the base for the effectiveness of energy saving as well as the cluster nodes.
Keywords: Target tracking; multi-sensor data fusion, WSNs, ETR-DF.Viet Huy Duongdvh_itdr@yahoo.comDinh Viet Nguyenvietnd@vnu.edu.vn2016-12-14T08:29:23Z2016-12-14T08:29:23Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2027This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20272016-12-14T08:29:23ZSelection of lactic acid bacteria producing bacteriocinIn this work, lactic acid bacteria were isolated from 10 samples of the traditionally fermented foods (5 samples of Vietnamese fermented pork roll and 5 samples of the salted field cabbage) and 5 samples of fresh cow milks. These samples were collected from households in Vietnam. 22 strains of lactic acid bacteria were isolated for inhibition to Lactobacillus plantarum JCM 1149. Of these, only 2 strains including DC1.8 and NC1.2 have rod shape, the others have coccus shape. There were 7 strains showing higher antibacterial activity and selected forchecking spectrum of antibacteria with indicator bacteria consistting of Bacillus subtilis ATCC 6633, Enterococcus faecium JCM 5804 and Staphylococcus aureus TLU. . . By which, 3 strains including NC3.5 (from Vietnamese fermented pork roll), DC1.8 (from salted field cabbage) and MC3.19 (from fresh cow milk) were selected because of their higher antibacterial ability. However, the antibacterial activity of the lactic acid bacteria can be based on disposable compounds of them and some other antibacterial compounds produced during of their growth (such as lactic acid, H2O2, bacteriocins, …). For seeking lactic acid bacteria with capability of producing bacteriocins, antibacterial compounds with protein nature, , 3 above strains were checked sensitive to proteases (including protease K, papain, α – chymotrypsin and trypsin). Because bacteriocins are proteinaceous antibacterial compounds, so their antibacterial activity will be reduced if proteases are added. The result showed DC1.8 and MC3.19 were capable of producing bacteriocin during culture process. These two strains were classified to species based on analysis chemical characterisitcs by standard API 50 CHL kit and phylogeny relationship by 16s rRNA sequences. DC1.8 was identified as Lactobacillus acidophilus and MC3.19 as Lactococcus lactis.Thi Quyen Haquyenht@vnu.edu.vnThi Minh Tu Hoahoaminhtu@gmail.com2016-12-14T08:27:44Z2016-12-14T08:27:44Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1984This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19842016-12-14T08:27:44ZNghiên cứu mô hình nhân vật ảo biểu cảm trên khuôn mặt ba chiều nói tiếng ViệtThi Duyen NgoDuyennt@vnu.edu.vn2016-12-12T16:48:54Z2016-12-12T16:48:54Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2036This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20362016-12-12T16:48:54ZSide information creation using adaptive block size for distributed video codingThi Huong Thao NguyenHuu Tien VuVan San VuVan Xiem Hoangxiemhoang@vnu.edu.vnThanh Ha Leltha@vnu.edu.vnTrieu Duong Dinhduongdt@vnu.edu.vn2016-12-12T16:31:23Z2016-12-12T16:31:23Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2200This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/22002016-12-12T16:31:23ZResearch, Design and Fabrication of a Data Transceiver Module for Vessel Monitoring SystemsIn this paper, we present a data transceiver module used in vessel monitoring systems. The realized transceiver is flexible, quick in response and low cost. The information about identification (ID), longitude, latitude and state of the vessel are packed into data frames and verified by a system prototype. The proposed system is capable of tracking targets and with information displayed on a computer’s screen. The longitude and latitude data can be applied to Global Positioning System (GPS) using a Ublox Neo – M8N. The control board, data processing module and displaying module use STM32F407, 2.4 inch 320 x 240 TFTLCD, respectively. In addition, by using ADF7021 transceivers, the obtained data is FSK/MSK modulated with flexible changing of transmit/receive frequency in the band VHF-UHF, data rate from 0.05 kbps to 32.8 kbps, high receiving sensitivity. All experimental results are reported.Dinh The Anh NguyenXuan Huy LeTuan Anh Vutanhvu@vnu.edu.vnGia Duong Bachduongbg@vnu.edu.vn2016-12-12T03:59:27Z2016-12-12T03:59:27Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2035This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20352016-12-12T03:59:27ZSpatial - Temporal Feature Extraction based Adaptive Search Range for Effective Frame Rate Up - ConversionVan Xiem Hoangxiemhoang@vnu.edu.vnDuong Trieu Dinhduongdt@vnu.edu.vnThanh Ha Leltha@vnu.edu.vn2016-12-12T03:52:24Z2016-12-12T03:52:24Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2005This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20052016-12-12T03:52:24ZSynthesis of Gold Nanoparticles Capped with Quaterthiophene
for Transistor and Resistor Memory DevicesMai Ha HoangThanh Toan DaoThi Thu Trang NguyenPhuong Hoai Nam Nguyennamnph@vnu.edu.vnTrinh Tung Ngo2016-12-08T16:57:47Z2016-12-08T16:59:05Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2194This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21942016-12-08T16:57:47ZInfluence of dual-frequency combination on the quality improvement of ultrasound tomographyThe most useful feature of ultrasound tomography founded on the inverse scattering theory is that it can detect small structures below the wavelength of the pressure wave. A popular method introduced in ultrasound tomography is the Distorted Born Iterative Method (DBIM). Recently, the dual-frequency combination technique has been utilized to improve the reconstruction quality and increase the convergence rate of the DBIM. This method uses two frequencies, f_1 (low) and f_2 (high), to estimate the sound contrast in N_f1 and N_f2 iterations, respectively. However, the influence of these iteration parameters on the overall performance of the system is not yet known. In this paper, it is shown by using the simulation technique that if we do not pay attention to the choice of these parameters, the reconstruction quality might be worse than that using a single frequency. Furthermore, we focus on the best way to select the parameters in order to improve the reconstruction quality of ultrasound tomography. Given a fixed sum N iter of N_f1 and N_f2 , simulation results show that the best value of N_f1 is N_iter/2; this choice of parameters offers a normalized error that reduces by 67.6%, compared to the conventional DBIM using a single frequency.Quang Huy Tranhuytq@gmail.comDuc Tan Trantantd@vnu.edu.vnHuu Tue Huynhhhtue@hcmiu.edu.vnThat Long Tonttlong@hcmiu.edu.vnLinh Trung Nguyenlinhtrung@vnu.edu.vn2016-12-08T16:54:49Z2016-12-08T16:55:27Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2190This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21902016-12-08T16:54:49ZFast tensor decompositions for big data processingTensors, as a natural extension of matrices, and their decompositions provide important tools in many disciplines such as psychometrics, signal processing, data communication, computer vision, and machine learning. The main objective of this paper is to briefly review several recent state-of-the-art approaches for large-scale tensor data which is a crucial part of big data. Moreover, we also introduce our own contributions on this topic.Viet Dung NguyenKarim Abed-MeraimLinh Trung Nguyenlinhtrung@vnu.edu.vn2016-12-08T16:53:26Z2016-12-08T16:54:29Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2189This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21892016-12-08T16:53:26ZEstimation of elasticity and viscosity in heterogeneous medium using FDTD method and AHI algorithmIn this paper we present an efficient examplebased method for Gaussian denoising of CT images. In the proposed method, an image is considered as a sum of the three frequency bands: low-band, middle-band and high-band. We assume that the noise component is often mixed into the middleband and the high-band in order to better preserve the highfrequency details in the image we perform denoising on these two bands. The method is based on a sparse representation model in which a set of standard images is used to construct the example dictionaries. The experimental results demonstrate that the proposed denoising method can preserve well the highfrequency details. The objective and subjective comparisons also show that the proposed our method outperforms other state-of-the-art denoising methods.Quang Hai LuongDuc Tan Trantantd@vnu.edu.vnLinh Trung Nguyenlinhtrung@vnu.edu.vnHuu Tue Huynh2016-12-08T03:54:14Z2016-12-08T03:54:14Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2171This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21712016-12-08T03:54:14ZIntegration of compressed sensing and frequency hopping techniques for ultrasound tomographyThe FH-DBIM (frequency hopping distorted Born iterative method) is a promising approach for imaging tumors at the level of biological tissues. This uses multiple frequencies for producing images, leading to large computational complexity and storage space (i.e. for each frequency, NtNrN2 calculations are required). It is a main barrier that the FH-DBIM approach is not fully exploited in commercialized devices. Therefore, in this paper, we propose an alternative algorithm for significant reducing the computational complexity of the FH-DBIM by integrating compressed sensing and frequency hopping techniques for the DBIM. That is, the needed number of measurements for imaging is tremendously reduced in comparison with the conventional one. The proposed algorithm â�� CS-FH-DBIM-offers a new prospect for being able to image high-resolution images at the level of biological tissues in practice.Quang Huy Trantranquanghuysp@gmail.comDuc Tan Trantantd@vnu.edu.vn2016-12-08T03:46:19Z2016-12-08T03:46:19Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2023This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20232016-12-08T03:46:19ZPreparation and characterization of La0.67-xLi3xTiO3 solid-state electrolyte used for electrochromic mirrorsWith the aim of producing all-solid-state electrochromic mirrors, La0.67-xLi3xTiO3 (LLTO) and the WO3 were prepared by electron beam deposition. The LLTO (with x = 0.11) powder was synthesized by thermally ball-grinding method and the Li+ ionic conductivity of the LLTO ceramic targets was found to be of ca. 3.25 10-3 S/cm. Using LLTO targets for e-beam evaporation, 300 nm – thick films with the Li+ ionic conductivity of 5.50 10-5 S/cm were deposited. Combining LLTO films with WO3/ITO and LiMn2O4 layers, all-solid-state electrochromic mirrors with a laminar structure of Al/LiMn2O4/LLTO/WO3/ITO were prepared. The reversible reflectance of the mirrors was well controlled by applying polarized potentials onto the ITO electrode. The obtained results suggest useful applications for electrochromic windows working as a smart reflectance mirror that can be used for auto rear-view mirrors.Dinh Trong LeNang Dinh Nguyendinhnn@vnu.edu.vnHong Thanh Do2016-12-08T03:44:23Z2016-12-08T03:44:23Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1985This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19852016-12-08T03:44:23ZA Strongest Assumption Generation Method for Component-Based Software VerificationThis paper presents a method for generating strongest assumptions during component-based software verification. The key idea of this method is to improve the technique for answering membership queries of the Teacher when responding to the Learner in theHoang Viet Tranvietth@vnu.edu.vnChi Luan Leluanlc@utt.edu.vnNgoc Hung Phamhungpn@vnu.edu.vn2016-12-08T03:42:01Z2016-12-08T03:42:01Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2007This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20072016-12-08T03:42:01ZIndoor Fire Detection using Wireless Sensor NetworksIn this paper, we propose an algorithm for early detection of indoor fire based on temperature and light data collected by wireless sensor networks. Our goal is to develop an affordable, acceptable, detection method based on wireless sensor networks with cheap and highly available sensors. Experimental results show that our proposed algorithm is able to detect fire quickly and accurately.Thanh Le Dinhthanhld@vnu.edu.vnDai Tho Nguyenthond@vnu.edu.vn2016-12-08T03:40:11Z2016-12-08T03:40:49Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2004This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20042016-12-08T03:40:11ZSynthesis and Characterization of Polymeric Graphene-Quantum-Dots based Nanocomposites for Humidity SensingGraphene quantum dots (GQDs) were synthesized and incorporated with polyethylenedioxythiophene: poly(4-styrenesulfonate) (PEDOT:PSS) and carbon nanotube (CNT) to form a composite that can be used for humidity sensors. The 600 nm-thick composite films contained bulk heterojunctions of CNT/GQD and CNT/PEDOT:PSS. The sensors made from the composites responded well to humidity in a range from 60 to 80% at room temperature and atmospheric pressure. With a CNT content of 0.4 wt.% (GPC-1) to 0.8 wt.% (GPC-2) and 1.2 wt.% (GPC-3), the sensitivity of the humidity sensing devices based on CNT-doped graphene quantum dot-PEDOT:PSS composites was increased from 4.5% (GPC-1) to 9.0 % (GPC-1) and 11.0 % (GPC-2), respectively. The fast response time of the GPC sensors was about 20 s and it was much improved due to CNTs doping in the composites. The best value of the recovery time was found to be of 40 s, for the GPC composite film doped with 1.2 wt.% CNT content.Minh Long LamNang Dinh Nguyendinhnn@vnu.edu.vnQuang Trung Tran2016-12-08T03:40:02Z2016-12-08T03:40:02Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1992This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19922016-12-08T03:40:02ZSpatial-Temporal Feature Extraction based Adaptive Search Range for Effective Frame Rate-Up ConversionFrame rate up conversion (FRUC) has been playing an important role in the recent development of advanced television systems due to its benefits on both increasing the viewing quality experiences and reducing the cost of video transmission. However, with the increasing of video resolutions, notably from Standard Definition (SD) to High Definition (HD), FRUC is now asked to provide not only better interpolated frames quality but also lower time processing. Therefore, in this paper, we propose a novel spatial – temporal feature extraction based adaptive search range for effective FRUC. In the proposed adaptive search range scheme, a set of temporal and spatial features are carefully defined and exploited to adaptively assign an appropriate search range value to each considered block; thus, directly reducing the FRUC time processing. Moreover, since the optimal search range can be employed; the quality of interpolated frames is significantly improved. Experimental results conducted for a rich set of video test sequences shown the advantages of the proposed FRUC scheme, notably in both subjective objective image quality improvement and time processing reduction.Van Xiem Hoangxiemhoang@vnu.edu.vnTrieu Duong Dinhduongdt@vnu.edu.vnThanh Ha Leltha@vnu.edu.vn2016-12-07T08:26:35Z2016-12-07T08:27:20Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2022This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20222016-12-07T08:26:35ZCharacterization of Electrochromic Properties of Polyaniline Thin Films Electropolymerized in H2SO4 SolutionPolyaniline (PANI) onto indium-doped tin-oxide (ITO)-coated glass samples were prepared by electroopolymerization in 0.5 M H2SO4 solution. Structure and morphology characterization of the PANI films demonstrated that the films were grown onto ITO substrates in the form of polycrystalline microbelts separated by micropores. By analysing the UV-Vis absorption spectra of the PANI films, the energy bandgap was found to be approximately 2.75 eV. The PANI/ITO films exhibited a good reversible electrochromic display (ECD) performance when cycled in 0.1 M LiClO4 + pro-pylene carbonate. The response time of the ECD coloration was found to be as small as 15 s and the coloration efficiency was found to be 8.85 cm2 C-1. After 100 cycles of the ECD performance, the cyclic voltammetry curve of the working electrode maintained unchanged. This demonstrates that the electropolymerized PANI films can be served as a good candidate for ECD applications, taking advantage of their excellent properties in terms of chemical stability.Hai Ninh DangThi Thao Tranthaott@vnu.edu.vnDuy Long PhamNang Dinh Nguyendinhnn@vnu.edu.vn2016-12-07T08:19:44Z2016-12-07T08:21:27Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1970This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19702016-12-07T08:19:44ZA Method to Specify Software Functional Requirements for System Test Case GenerationMinh Hue ChuDuc Hanh Danghanhdd@vnu.edu.vnNgoc Binh Nguyennnbinh@vnu.edu.vn2016-12-07T08:12:27Z2016-12-07T08:13:08Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2165This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21652016-12-07T08:12:27ZDistributed coverage control for networked multi-robot systems in any environmentsWe present a distributed coverage control for networked multi-robot systems in any environments. The distributed coverage control is developed by combining the interconnected hexagon-lattices based coverage and the hierarchical distributed control of networked multi-robot systems. The distributed coverage control is capable of driving mobile robots to move in the network to cover any environments. We have demonstrated the effectiveness of this distributed coverage control for the network of up-to 14 real mobile robots in both convex and non-convex real-world environments.Duy Hung Phamhungpd@vnu.edu.vnQuang Vinh Tranvinhtq@vnu.edu.vnTrung Dung Ngontdung@gmail.com2016-12-07T08:11:03Z2016-12-07T08:12:11Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2164This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21642016-12-07T08:11:03ZMusicbot: Edutainment with a reconfigurable robotic systemApproaching a new study subject could be a problem to everyone, especially children. In particular, children might lose the interest when learning music due to their lacking fundamental knowledge. Using tangible programming on modular robotics may be an effective way for teaching and learning music. In this paper, we present an education and entertainment design, so-called learning through playing, through a real-world musical application using modular robotics.Van Tung LeDuy Hung Phamhungpd@vnu.edu.vnTrung Dung Ngontdung@gmail.com2016-12-07T02:13:58Z2016-12-07T02:13:58Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2163This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21632016-12-07T02:13:58ZA variant of the cyclic pursuit scheme for consensus in multi-agent systemsIn this paper, we present a solution to the rendezvous problem using a variant of the cyclic pursuit, in which agent i follows agent i +1 modulo η and in which agent i follows agent i−1 modulo n. With the variant of the cyclic pursuit, we aim to increase the convergence rate compared to the cyclic pursuit A generalized variant of the proposed strategy is also presented to guide mobile agents to rendezvous at a desired point We provide simulation results to illustrate the key theoretical results.M. IqbalP. D. HungJ. LethT. D. Ngo2016-12-06T05:12:16Z2016-12-06T05:12:16Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2105This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21052016-12-06T05:12:16ZAir pollution mapping from high spatial resolution satellite images: a case study in HanoiViet Hung LuuDuc Chuc ManChinh Ke LuongQuang Hung Buihungbq@vnu.edu.vnThi Nhat Thanh Nguyenthanhntn@vnu.edu.vn2016-12-06T05:11:13Z2016-12-06T05:11:13Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2097This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20972016-12-06T05:11:13ZComparison of Various Image Fusion Methods for Impervious Surface Classification from VNREDSat-1Impervious surfaces are important indicators for urban development monitoring. Accurate mapping of urban impervious surfaces with observational satellites, such as VNREDSat-1, remains challenging due to the spectral diversity not captured by an individual PAN image. In this article, five multi-resolution image fusion techniques were compared for the task of classifting urban impervious surfaces. The result shows that for VNREDSat-1 dataset, UNB and Wavelet tranformation methods are the best techniques in reserving spatial and spectral information of original MS image, respectively. However, the UNB technique gives the best results when it comes to impervious surface classification, especially in the case of shadow areas included in non-impervious surface group.Viet Hung LuuVan Manh PhamDuc Chuc ManQuang Hung Buihungbq@vnu.edu.vnThi Nhat Thanh Nguyenthanhntn@vnu.edu.vn2016-12-06T05:09:52Z2016-12-06T05:09:52Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2106This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21062016-12-06T05:09:52ZA Watermark Algorithm Against De-Synchronization AttacksIn this paper, a robust method to the ability of the watermark to resist against attacks is proposed for hiding information into images. The proposed method is blind because the original image is not required at the decoder to recover the embedded data. The robustness of the watermarking scheme is inspired by using a PJND (Pyramidal Just Noticeable Difference) model and the message is inserted into these DoG (Difference of Gaussians) [1, 2]. Our proposal takes into account three main characteristics of Human Visual System, namely: contrast sensitivity, luminance adaptation and contrast marking. Therefore, it not only provides an invisible and robust watermarking but also optimizes watermarking capacity. The performance of the proposed technique is evaluated by a series of experiments with different input images. In terms of transparency, besides using the subjective experiments, eight objective metrics are calculated in comparison with other methods such as PSNR, MSSIM, SVDm, etc. Our approach always presents the outperform values. In terms of robustness, many kinds of attacks from global transformation (rotation, scaling, etc) to local transformation (stirmark, checkmark benchmarks, de-synchronization attacks) are implemented. Many image processing tools are applied to simulate the attacks such as Print-Screen, Using Photo editing software, Camcorder, Print-Scan, etc. The experimental results show an outstanding robustness in resisting these attacks.Viet Nguyen Luongnguyenlv@vnu.edu.vnNhat Tien TrinhVan Canh Ho2016-12-06T04:53:01Z2016-12-06T04:53:01Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2153This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21532016-12-06T04:53:01ZraSAT: An SMT Solver for Polynomial ConstraintsXuan Tung VuVan Khanh Tokhanhtv@vnu.edu.vnMizuhito Ogawa2016-12-05T04:15:40Z2016-12-05T04:15:40Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2099This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20992016-12-05T04:15:40ZA simple diagram for data transmission using Manchester codeThe paper proposes a simple diagram for data
transmission on the frequency of 2.4GHz based on the
Manchester code. Unlike the classical methods, the receiver
usually performs some feedback loops to stabilize the gain to control the sampling at exact position (timing) of the symbol or to synchronize and track frequency. The proposed diagram only uses a cut-off signal to detect data directly without any feedback loops. Although it is simple, the proposed diagram still obtains high stable operation and wide input dynamic range. The experiment was tested by transmitting a 64kbit image file through an embedded FPGA system. Due to the use of Manchester code, then the cost of the proposed method depends only on the bandwidth. Furthermore, the proposed diagram is more suitable for indoor transmission applications and transmitting high-speed data by using Ultra Wide Band (UWB) pulsesAnh Vu Trinhvuta@vnu.edu.vnVan Thanh Phamphamvanthanh1209@gmail.com2016-12-05T04:12:21Z2016-12-05T04:12:21Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2104This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/21042016-12-05T04:12:21ZField Informatics: Application of ICT to environment management and monitoringQuang Hung Buihungbq@vnu.edu.vnThi Nhat Thanh Nguyenthanhntn@vnu.edu.vnHai Chau Nguyenchaunh@vnu.edu.vn2016-12-05T03:18:08Z2016-12-05T03:18:08Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2065This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20652016-12-05T03:18:08ZActivity Recognition based on Clustering Methods for Senior Homecare ServicesIn modern society, most seniors prolong their
independence. To guarantee the safety of them when
living on their own, we need to monitor their activities
all the time and react to critical situations. The rapid
advances in wireless networks, wearable sensors, and
communications technologies pave the way for the
advent of homecare service systems. Activity
recognition is a crucial task in building such systems.
This paper investigates two clustering methods, kmeans
and Self-organizing map (SOM) for recognizing
human daily activities. An experiment is performed on
a real data set. The results show that k-means performs
pretty well in classifying two activities; however the
accuracy is pretty low when the data set is scaled up to
five activities. SOM outperforms k-means in most cases
of data sets. On average, the resulting accuracy of
SOM is 87% and of k-means is 54% for five activities.
As a result, SOM is most suitable to be integrated in
systems for providing remote homecare services.Thi Hong Nhan Vuvthnhan@vnu.edu.vnYang Koo LeeNamsrai Oyun-Erdene2016-12-05T03:13:03Z2016-12-05T03:13:03Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2071This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20712016-12-05T03:13:03ZBuilding ancestral recombination graphs for whole genomesAbstract— The Ancestral Recombination Graph (ARG) plays an important role in human population genetics.
Nevertheless, most current ARG inference algorithms are only applicable to small data sets due to their computational
burden. Margarita by Minichiello and Durbin [1] can handle larger data sets; however, it is still not feasible
at genome scale. We hereby propose a heuristic algorithm, called ARG4WG, to construct plausible ARGs from
thousands of whole chromosome samples, in which the so-called longest shared end, i.e. the longest match between
left or right ends of sequences, is used for recombination in the building process. This strategy allows ARG4WG to
significantly reduce the computational cost, by working hundreds to thousands times faster than Margarita.
ARG4WG leads to ARGs with fewer numbers of recombination events on real data sets. Margarita is slightly better
than ARG4WG in reconstructing tree topology on simulated data. The ARGs resulted from our algorithm also performed
reasonably well in an association study with 5560 haplotypes across a whole Chromosome 11 of the Gambia
dataset. These results indicate that ARG4WG is a good candidate for genome-wide association study from
large data sets.Thao NguyenSy Vinh Levinhls@vnu.edu.vnHai HoSi Quang Le2016-12-05T03:08:54Z2016-12-05T03:08:54Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2069This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20692016-12-05T03:08:54ZMechanisms of sex determination and transmission ratio distortion in Aedes aegyptiBackground: More effective mosquito control strategies are urgently required due to the increasing prevalence of
insecticide resistance. The sterile insect technique (SIT) and the release of insects carrying a dominant lethal allele
(RIDL) are two proposed methods for environmentally-friendly, species-targeted population control. These methods
may be more suitable for developing countries if producers reduce the cost of rearing insects. The cost of control
programs could be reduced by producing all-male mosquito populations to circumvent the isolation of females
before release without reducing male mating competitiveness caused by transgenes.
Results: An RNAi construct targeting the RNA recognition motif of the Aedes aegypti transformer-2 (tra-2) gene does
not trigger female-to-male sex conversion as commonly observed among dipterous insects. Instead, homozygous
insects show greater mortality among m-chromosome-bearing sperm and mm zygotes, yielding up to 100 % males
in the subsequent generations. The performance of transgenic males was not significantly different to wild-type
males in narrow-cage competitive mating experiments.
Conclusion: Our data provide preliminary evidence that the knockdown of Ae. aegypti tra-2 gene expression causes
segregation distortion acting at the level of gametic function, which is reinforced by sex-specific zygotic lethality.
This finding could promote the development of new synthetic sex distorter systems for the production of genetic
sexing mosquito strains.
Keywords: Aedes aegypti, Sex determination, Transformer-2, Meiotic drive, Spermatogenesis, CulicinaePhuc Hoangkimhpoxford@gmail.comTze Min TeoThien Xuan HoLe Sy Vinhvinhls@vnu.edu.vn2016-12-04T13:44:22Z2017-01-17T02:46:19Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2062This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20622016-12-04T13:44:22ZThe 2016 Annual Scientific Report of VNU University of Engineering and TechnologyThe University of Engineering and Technology (UET) was founded in 2004 as a member university of Vietnam National University, Hanoi (VNU).
The last only five years have seen immense progresses in the development of our university in various aspects of its activities thanks to the great efforts put in by the government with strong financial supports, by the VNU with steering leadership and administration, by the national and international educational institutions and corporations in fruitful collaborations and advices, and by all the staff and students of the UET with determination, hard work and patience.
Today, our university has built up a solid foundation for a sustainable and dynamic development in coming years. This solid foundation consists of a completed system of well-designed programs at both undergraduate and graduate levels, renovated teaching and learning facilities, a just limited but strong and advanced research infrastructure with state-of-the-art and completed equipment systems, a sustainable and fruitful collaboration with leading research and educational institutions in the country, and a bright, young, well-educated and welltrained faculty who are eager to take on advanced research and studies. All these have made our university a prestigious institution and firmly established its education and research capabilities. This is proved by the facts that only in the last four years our university has established close and solid ties and cooperation with prestigious foreign universities, just to name a few, the University Paris-Sud 11 (France), Japan Advanced Institute of Science and Technology, the National University of Singapore, Nanyang Technological University (Singapore), University of New South Wales and with famous international industrial and technological corporations such as Samsung, Toshiba, NEC, Mitani, Human Resocia, IBM, and other well-known institutions in the region and around the world. This is also proved in a convincing way by the facts that only in the last two years, our university has been granted several significant research projects from various national research programs. Our university has become an attractive destination for talented students at all training levels. We are proud that our university is the only Vietnamese higher-education institution that has one among the 100 best student’s teams all over the world participating the World Final of the ACM International Collegiate Programming Contest (rank #29 in 2015). We are also proud that in this year, our faculty has won an award in the National Contest in Information Technology entitled “Vietnamese Talent Award” and three awards in the VNU Science & Technology Award for the period of 2011-2015. In the coming period, we shall put our great efforts to solidify our strength and prestige. We shall widen our training scope while paying significant attention to further improvement on the education quality. We shall strongly enhance our concentrated research activity by exploring efficiently and effectively our well established foundation for a further dynamic development and, thus, contributing our crucial part to the socio-economic development of our nation and fulfilling our great missions clearly assigned by the government in the decision on the establishment of our university. To do that, innovative thinking and acting by all faculty, administrative staff and students are of deciding role and of crucial importance.Xuan Tu Trantutx@vnu.edu.vnAnh Cuong Lecuongla@vnu.edu.vnDuc Tan Trantantd@vnu.edu.vnManh Thang Phamthangpm@vnu.edu.vnThi Huong Giang Dogiangdth@vnu.edu.vn2016-12-03T07:23:57Z2016-12-03T07:23:57Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2011This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20112016-12-03T07:23:57ZPerformance of Cooperative Spectrum Sensing over Lognormal channel using EGC-based Soft DecisionIn cooperative spectrum sensing based on energy detection, there are two common techniques taken into account - Hard Decision Combining (HDC) and Soft Decision Combining (SDC). Several researches has addressed that SDC has better detection performance than HDC. Therefore, in this paper, we focus on Equal Gain Combining (EGC)–based soft decision under Lognormal fading channel. We propose using Moment-generating function (MGF) to approximate probability density function (PDF) of power sum of lognormal variables. Then we utilize approximated PDF for evaluating cooperative detection performance. Moreover, we also consider the optimal number of cooperating Cognitive Radios (CRs) using EGC-based soft decisionThi Thai Mai Dinhdttmai@vnu.edu.vnQuang Vinh Buivinhbq_58@vnu.edu.vnTruong Sinh Nguyenvinhnt_58@vnu.edu.vnVan Han Nghiemhannv_58@vnu.edu.vnHong Giap Legiaplh_58@vnu.edu.vnVan Hung Nguyenhungnv.vnu.uet@gmail.com2016-12-03T07:22:51Z2017-01-13T02:28:03Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2058This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20582016-12-03T07:22:51ZTrường Đại học Công nghệ-ĐHQGHN, ngôi trường tiên phong trong nghiên cứu và đào tạo về an toàn thông tinCác giảng viên của Trường ĐHCN - ĐHQG HN bắt đầu nghiên cứu và đào tạo về An toàn thông tin từ rất sớm với những cây đại thụ như GS. TSKH Phan Đình Diệu, PGS. TS Trịnh Nhật Tiến. Trong thời gian qua, trường ĐHCN - ĐHQG HN đã có nhiều đề tài Luận án Tiến sĩ, Luận văn Thạc sĩ và Khóa luận tốt nghiệp của sinh viên về An tòn thông tin. ĐHQG HN đã cho phép Trường ĐHCN mở chuyên ngành đào tạo về An toàn thông tin. Côn g tác nghiên cứu và đào tạo về ATTT ở Trường ĐHCN - ĐHQG HN ngày càng phát triển, ngày càng có sự kết nối giữa CNTT và ĐT - VT và các khoa khác trong trường, các đơn vị khác trong và ngoài nước.Phe Do Ledolp@vnu.edu.vn2016-12-03T07:18:43Z2016-12-03T07:18:43Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1955This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19552016-12-03T07:18:43ZOn Model Finding with Constraint PatternsDuc Hanh Danghanhdd@vnu.edu.vnAnh Hoang Truonghoangta@vnu.edu.vnVan Hung Dang2016-12-03T07:12:48Z2016-12-03T07:12:48Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1954This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19542016-12-03T07:12:48ZCalculating Statically Maximum Log Memory Used by Multi-threaded Transactional ProgramsAnh Hoang Truonghoangta@vnu.edu.vnNgoc Khai NguyenVan Hung DangDuc Hanh Danghanhdd@vnu.edu.vn2016-12-03T07:11:00Z2016-12-03T07:11:00Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2042This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20422016-12-03T07:11:00ZA Solution for Automatically Malicious Web Shell and Web Application Vulnerability DetectionVan Giap Legiaplvk57@gmail.comHuu Tung Nguyenhtung.nht@gmail.comDang Nhac LuNgoc Hoa Nguyenhoa.nguyen@vnu.edu.vn2016-12-03T07:02:59Z2016-12-03T07:02:59Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1982This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19822016-12-03T07:02:59ZA Method for Automated Test Cases Generation from Sequence Diagrams and Object Constraint Language for Concurrent ProgramsThis paper proposes an automated test cases generation method from sequence diagrams, class diagrams, and object constraint language. The method supports UML 2.0 sequence diagrams including eight kinds of combined fragments describing control flow of systems. Test cases are generated with respect to the given concurrency coverage criteria. With strong concurrency coverage, generating exhaustive test cases for all concurrent interleaving sequences is exponential in size. The key idea of this method is to create selection of possible test scenarios in special case of exploring the message sequence with their possible interleaving in parallel or weak sequencing fragments. Test data for testing loop fragments are also generated. We implement a tool to automate the proposed method and studied its feasibility and effectiveness. Experimental results show that the method can generate test cases on demand to satisfy a given concurrency coverage criterion and can detect up to 74. 5% of seeded faults.Thi Dao Vuvtdao@bcy.gov.vnNgoc Hung Phamhungpn@vnu.edu.vnViet Ha Nguyenhanv@vnu.edu.vn2016-12-03T07:01:10Z2016-12-03T07:01:10Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2033This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20332016-12-03T07:01:10ZReduced Reference Quality Metric for Synthesized Virtual Views in 3DTVMulti-view video plus depth (MVD) has been widely used owing to its effectiveness in three-dimensional data representation. Using MVD, color videos with only a limited number of real viewpoints are compressed and transmitted along with captured or estimated depth videos. Because the synthesized views are generated from decoded real views, their original reference views do not exist at either the transmitter or receiver. Therefore, it is challenging to define an efficient metric to evaluate the quality of synthesized images. We propose a novel metric—the reduced-reference quality metric. First, the effects of depth distortion on the quality of synthesized images are analyzed. We then employ the high correlation between the local depth distortions and local color characteristics of the decoded depth and color images, respectively, to achieve an efficient depth quality metric for each real view. Finally, the objective quality metric of the synthesized views is obtained by combining all the depth quality metrics obtained from the decoded real views. The experimental results show that the proposed quality metric correlates very well with full reference image and video quality metrics.Thanh Ha Leltha@vnu.edu.vnTung Long VuongTrieu Duong Dinhduongdt@vnu.edu.vnSeung-Won Jung2016-12-03T06:59:18Z2016-12-03T06:59:18Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2059This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20592016-12-03T06:59:18ZAn efficient multilevel healthy cloud system using Spark for smart clothesNowadays, we can find part of people into the suboptimal health status. However, most of them have not enough time for health examinations regularly. Smart clothes which are wearable and convenient devices for monitoring physiological signals solve this problem. In this study, we develop an efficient multilevel healthy cloud system to analyzing data collected from CGU smart clothes. The cloud system classifies the raw data into three types: normal data, continuous data, and multimedia data. After that, the cloud system analyzes data and predict diseases using Apache Spark. And then, the system will transfer final results to smartphones. The experimental result shows that the cloud system achieves very high-speed performance. Moreover, the system has friendly health information presentation and effective authorization process to help doctors and patients contact each other.Minh Khoi Lekhoilm@widelab.orgHsien-Tsung Changsmallpig@widelab.orgYi-Min Changxboxhigh@widelab.orgYi-Hao Hua02284989@widelab.orgHuan-Ting ChenB9829006@widelab.org2016-12-02T08:25:05Z2016-12-02T08:25:05Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1999This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19992016-12-02T08:25:05ZPerformance of soft frequency reuse in random cellular networks in Rayleigh-Lognormal fading channelsSinh Cong Lamcongls@vnu.edu.vnKumbesan SandrasegaranQuoc Tuan Nguyentuannq@vnu.edu.vn2016-12-02T06:51:59Z2016-12-02T06:51:59Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2024This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20242016-12-02T06:51:59ZSynthesis and Characterization of Ag/PEDOT:PSS films used for NH3 selective sensingNano-Ag/PEDOT-PSS films were prepared by spin-coating technique. SEM surface morphology, Raman spectra and gas sensing of methanol, humidity and NH3 were studied. The obtained results showed that the resistance of Ag/PEDOT:PSS sheets exposed to gases related to the generation of electrons from the gases adsorption that eliminated holes as the major carriers in PEDOT:PSS. For NH3 gas the largest change of the resistance of Ag/PEDOT:PSS was observed. The less sensitivity of humidity and ethanol sensing was explained due to less dedoping reaction between H2O and ethanol vapor with Ag/PEDOT:PSS, recpectively. This suggests a potential application of the nano-Ag/PEDOT-PSS sensors for the selective monitoring NH3 gas in environment.Minh Long LamNang Dinh Nguyendinhnn@vnu.edu.vnQuang Trung Tran2016-12-01T06:07:44Z2016-12-01T06:08:00Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1998This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19982016-12-01T06:07:44ZImproving 3D-TV View Synthesis Using Motion Compensated Temporal InterpolationNowadays, the development of three-dimension (3D) video applications such as three-dimensional television (3D-TV) and free-viewpoint television (FTV) has greatly increased human experiences. View synthesis method like depth-image-based-rendering (DIBR), plays a significant role in 3D content creation, 3D transmission, and has been integrated into video coding standards such as 3D-High efficiency video coding (3D-HEVC). However, the current DIBR method employs only the disparity correlation between views to create a so-called synthesized view; thus, unable to take full advantages of available synthesized information. In this paper, we propose a novel view synthesis method which takes advantages of not only the disparity correlation but also the temporal correlation between views. In the proposed method, an effective motion compensation based frame interpolation is employed to generate a temporal prediction view which is then combined with the DIBR rendered view to obtain the final synthesized view. Experimental results show that the proposed method can achieve the synthesized view with significantly outperforming other conventional techniques in terms of both peak signal-to noise ratio (PSNR) and subjective visual quality.Dinh Minh Leminhld_57@vnu.edu.vnTung Long VuongVan Xiem Hoangxiemhoang@vnu.edu.vnTrieu Duong Dinhduongdt@vnu.edu.vnThanh Ha Leltha@vnu.edu.vn2016-12-01T06:06:01Z2016-12-01T06:06:01Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1994This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19942016-12-01T06:06:01ZAn Efficient Log Management SystemServer monitoring is really necessary because this can help administrators to track users’ activities in order
to improve user management ability, load balancing as well as to detect DDoS attacks. Usually, server
monitoring is based on logging. However, logging system is always considered to be expensive in term of
storage, data collection, data searching and analysis. In this paper, we introduce eLMS, an efficient and scalable
log management system. In our system, the log files can be collected from multiple servers, stored in a scalable
manner, appropriately indexed and fast analysed. eLMS acts both in online and off-line modes and provides a
practical web-based monitoring interface. eLMS is based on a famous open-source core called ELK including
three main modules: ElasticSearch, LogStash and Kibana. However, by using queue and streaming technique
instead of uploading technique used in LogStash, eLMS is tested to be at least ten times faster than existing ELKVan Nam Nguyenvan.nam@vnu.edu.vnVan Cuong Tran2016-12-01T06:05:01Z2016-12-01T06:05:01Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/2002This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/20022016-12-01T06:05:01ZA Method for Automated Unit Testing of C ProgramsThis research proposes an automated test case generation method for C functions. In this method, the source code is transformed into a control flow graph corresponding to the given coverage criterion. After that, a list of feasible test paths is discovered by traversing the control flow graph using backtracking algorithm, symbolic execution, and Z3 solver. We also generate test cases for functions containing one loop or two-nested loop. A tool supporting the proposed method has been developed and applied to test on some C functions. The experimental results show the high coverage with the minimum number of test cases, the ability to improve the total time of the test case generation with a specified coverage criterion, and the increasing precision of checking the feasibility of test paths if comparing with the random technique. The experimental results display the potential usefulness of this tool for automated test case generation in practice.Duc Anh Nguyennguyenducanh@vnu.edu.vnNgoc Hung Phamhungpn@vnu.edu.vnViet Ha Nguyenhanv@vnu.edu.vn2016-12-01T04:25:33Z2016-12-01T04:25:33Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1981This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19812016-12-01T04:25:33ZFeature Extraction for Non-frontal FacesOne of the most challenge tasks in building a face recognition system is how to represent and extract good quality features from face images. The difficulties come from variations in head poses, illumination conditions, and facial expression. Although many researches have been done, most were carried on under constrained environments. Most researches concentrated on dealing with frontal faces. Processing non-frontal faces encounters more challenge because some features on faces become occluded dramatically. In this paper, we propose two models to extract features from non-frontal faces in the range of 30o to 90o. First, we use the Viola-Jones detection method to identify the pose of face images. Then, we use Active Appearance Model (AAM) to interpret face images. Lastly, the models are trained to know how to fit new images. To improve the efficiency of fitting, we apply a nonlinear parameter update method. Experimental results show that using nonlinear fitting for non-frontal can increase the accuracy of the AAM fitting, compared with some previous methods.Anh Tuan Doanhtuan140782@gmail.comThi Duyen NgoDuyennt@vnu.edu.vnThe Duy Buiduybt@vnu.edu.vn2016-12-01T04:23:13Z2016-12-01T04:23:13Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1980This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19802016-12-01T04:23:13ZA Framework for Modeling and Modular Verifying of Component-Based System DesignsThis paper introduces a framework for modeling and verifying safety properties of component-based systems (CBS) by extracting their models from designs in form of UML 2.0 sequence diagrams. Given UML 2.0 sequence diagrams of CBS, the framework extracts regular expressions exactly describing behaviors of the system. From these expressions, the proposed framework then generates accurate models represented by labeled transition systems (LTSs). After that, these models are used to modular check whether given designs satisfy required safety properties by using the assume-guarantee reasoning paradigm. This framework is not only useful for modeling and verifying designs at design phase, but also for effectively rechecking CBS in the context of software evolution. Implemented tools and experimental results are also presented in order to show the feasibilities and effectiveness of the proposed framework.Chi Luan Leluanlc@utt.edu.vnHoang Viet Tranvietth@vnu.edu.vnNgoc Hung Phamhungpn@vnu.edu.vn2016-12-01T03:47:59Z2016-12-01T03:47:59Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1953This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19532016-12-01T03:47:59ZA Type System for Counting Logs of Multi-threaded Nested Transactional ProgramsAnh Hoang Truonghoangta@vnu.edu.vnVan Hung DangDuc Hanh Danghanhdd@vnu.edu.vnXuan Tung Vu2016-12-01T02:28:21Z2016-12-01T02:28:21Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1977This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19772016-12-01T02:28:21ZDSMAV: An improved solution for multi-attribute search based on load capacitiesDHT (Distributed Hash Table) such as CHORD or PARTRY facilitates information searching in scalable systems. Two popular DHT-based approaches for range or multi-attribute search are to rely on attribute-value tree and a combination of attributes and values. However, tradeoff between a load balancing mechanism and query efficiency is a challenging task for such information searching systems. In this paper, we propose improved algorithms for a system called DSMAV in which information resources are distributed fairly among nodes and found based on multi-attribute queries in a small number of hop counts. Our system creates identifiers from resource names, each of which is a combination of attribute-value pairs (AV pairs). In order to overcome problem of load imbalance among nodes because of frequent appearance of AV pairs in many resource names, we control the quantity of information resources distributed to a node based on load capacity of each node. Moreover, periodical updating processes on a node enable our load balancing mechanism to be maintained accurately. As a result, our improvement evaluated by simulated results depicts a good degree of load balance as well as query efficiency.ThanhDat NguyenClaudiu Vasile KiforHoai Son Nguyensonnh@vnu.edu.vn2016-12-01T02:24:58Z2016-12-01T02:24:58Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1975This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19752016-12-01T02:24:58ZDevelopment of home simulation with thermal environment and electricity consumptionEnergy management systems have been developed in order to achieve goal of energy efficiency in the focused areas. Home simulation is one of the tools that can simulate electricity consumption based on the home appliances usage. However, several elements were ignored in traditional home simulation. In this paper, we introduce the home simulation, which can simulate not only the electric power and its consumption, but also the thermal energy consumption. Relationships among five elements are considered in the home simulation. To validate the performance of the proposed home simulation, a real experimental house is used to conduct the experiment. The results showed the ability of the proposed home simulation to simulate the thermal energy and estimate the temperature of various rooms with an error of 1.2 degrees Celsius. Furthermore, the electricity consumption is also simulated based on the human activity schedule and home appliances usage.Yoshiki MakinoKonlakorn WongpatikasereeTakashi OkadaHoai Son Nguyensonnh@vnu.edu.vnYuto LimYasuo Tan2016-12-01T02:24:01Z2016-12-01T02:24:01Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1952This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19522016-12-01T02:24:01ZAn OCL-based Framework for Model TransformationsDuc Hanh Danghanhdd@vnu.edu.vnMartin Gogolla2016-12-01T02:23:09Z2016-12-07T08:23:25Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1951This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19512016-12-01T02:23:09ZDomain-Driven Design Using Meta-Attributes: A DSL-Based ApproachMinh Duc LeDuc Hanh Danghanhdd@vnu.edu.vnViet Ha Nguyenhanv@vnu.edu.vn2016-12-01T02:20:00Z2016-12-03T07:07:21Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1950This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19502016-12-01T02:20:00ZDomain-Driven Design Patterns: A Metadata-Based ApproachMinh Duc LeDuc Hanh Danghanhdd@vnu.edu.vnViet Ha Nguyenhanv@vnu.edu.vn2016-12-01T02:18:03Z2016-12-01T02:18:03Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1893This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18932016-12-01T02:18:03ZBlack box modelling the thermal behaviour of ihouse using auto regressive and moving average (ARMA) modelModelling and simulation of the dynamic thermal behaviour of a building is important to test any proposed thermal comfort control system and strategy in the building. A simulation model can be obtained by using either the white box, grey box or black box modelling method. This research focuses on the usage of auto regressive and moving average (ARMA) model, a type of black box model that represents the dynamic thermal behaviour of iHouse testbed and uses real recorded data from the testbed and limited knowledge regarding the physical characteristics of the testbed. The performance of the ARMA model developed in this research is compared with the performance of House Thermal Simulator, a previously developed model, based on grey box modelling. Results obtained shows that ARMA model works better than House Thermal Simulator in some aspects.Shamsul Faisal Mohd HusseinHoaison NguyenShahrum Shah AbdullahYuto LimYasuo Tan2016-12-01T02:17:11Z2016-12-01T02:17:11Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1892This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18922016-12-01T02:17:11ZA Cluster-based File Replication Scheme for DHT-based File Backup SystemsDHT-based file backup systems can provide efficient mechanisms for resource placement and lookup. However, these systems must deal with irregular and frequent join/leave of nodes and the problem of load unbalancing between nodes. This paper presents an efficient file replication scheme based on DHT identifier space clustering in order to guarantee data availability and support load balancing for DHT-based file backup systems. The main idea of our method is to divide a DHT network into a number of clusters, each of which locally stores and maintains data chunks of data files to guarantee the data availability for backup data files even in the case of node churn occurred in the network. Further, backup nodes are selected among high-capacity nodes in clusters to achieve a good degree of load balancing. Simulation results demonstrate the effectiveness of our proposed scheme in comparison with other file replication schemes.Hoai Son Nguyensonnh@vnu.edu.vnDinh Nghia NguyenXuan Hoang Tran2016-11-30T04:55:52Z2017-01-05T02:42:44Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1948This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19482016-11-30T04:55:52ZNghiên cứu và thiết kế mô hình hệ thống giám sát hành vi trên bòNghiên cứu này tập chung vào việc đề suất xây dựng mô hình hệ thống giám sát hành vi trên bò, giúp theo dõi về sức khoẻ cũng như thời kỳ động dục trên bò. Báo cáo xây dựng mô hình mạng cảm biến không dây dựa trên mạng Zigbee, trong đó việc giám sát hành vi sẽ dựa trên hai thiết bị được thiết kế để gắn trên cổ bò và tại chân bò. Hai thiết bị này được thiết kế dựa trên cảm biến gia tốc 3 trục kết hợp với cảm biến góc. Đặc biệt, hai thiết bị này sẽ được truyền thông không dây để tạo thành một nốt mạng và dữ liệu tổng hợp sẽ được gửi về nốt điều phối. Việc lấy dữ liệu về trạng thái trên cả chân và cổ bò sẽ giúp nhận định hành vi trên bò một cách chính xácChinh Nguyen Dinhchinhnd@vnu.edu.vnCong Phi Khanh Phungphungcongphikhanh@gmail.comDuc Tan Trantantd@vnu.edu.vnVu Ha Lehalv@vnu.edu.vn2016-11-28T02:33:02Z2016-11-28T02:33:02Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1941This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19412016-11-28T02:33:02ZC-KPCA: Custom Kernel PCA for Cancer ClassificationAbstract Principal component analysis (PCA) is an effective and well-known method for reducing high-dimensional data sets. Recently, KPCA (Kernel PCA), a nonlinear form of PCA, has been introduced into many fields. In this paper, we propose a new gene selection, namely Custom Kernel principal component analysis (C-KPCA). The new kernel function for KPCA is created by combining a set of kernel functions. First, Singular Value Decomposition (SVD) is used to reduce the dimension of microarray data. Input space is then mapped to ...Van Sang HaHa Nam Nguyennamnh@vnu.edu.vn2016-11-24T09:20:05Z2016-11-24T09:20:05Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1939This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19392016-11-24T09:20:05ZFRFE: Fast Recursive Feature Elimination for Credit ScoringAbstract Credit scoring is one of the most important issues in financial decision-making. The use of data mining techniques to build models for credit scoring has been a hot topic in recent years. Classification problems often have a large number of features, but not all of them are useful for classification. Irrelevant and redundant features in credit data may even reduce the classification accuracy. Feature selection is a process of selecting a subset of relevant features, which can decrease the dimensionality, reduce the running time, and ...Van Sang HaHa Nam Nguyennamnh@vnu.edu.vn2016-11-24T09:13:32Z2016-11-24T09:13:32Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1928This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19282016-11-24T09:13:32ZError concealment using adaptive spatial interpolation for H.264/AVCThanh Ha Leltha@vnu.edu.vnTrieu Duong Dinhduongdt@vnu.edu.vnHye-soo KimByeong-Doo ChoiSung-Jea Ko2016-11-24T09:09:52Z2016-11-24T09:09:52Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1902This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19022016-11-24T09:09:52ZAn approach to analyzing execution preservation in Java program refactoringThi Huong DaoHong Anh LeNinh Thuan Truongthuantn@vnu.edu.vn2016-11-24T09:00:04Z2017-06-10T11:36:30Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1901This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19012016-11-24T09:00:04ZA New Method to Analyze Graphical User Interfaces of Android ApplicationsIn recent years, the number of Android smartphones increase dramatically and new applications are added numerously in Google store. Android developers usually have to deal with the difficulties such as limited capacity battery, screen design, and limited resources. Among them, specifying graphical user interfaces (GUI) of an application is one of the most important issues. This paper presents a new method to analyze GUI specifications of an Android application. We employ Event-B formal method and its refinement mechanism to formalize the specifications and to check if the constraints are satisfied. A running example of a Note application is given to illustrate the proposed method in detail.Hong Anh Lelehonganh@humg.edu.vnNinh Thuan Truongthuantn@vnu.edu.vn2016-11-24T08:59:10Z2016-11-24T08:59:10Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1900This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19002016-11-24T08:59:10ZFormal analysis of imprecise system requirements with Event‑BFormal analysis of functional properties of system requirements needs precise descriptions. However, the stakeholders sometimes describe the system with ambiguous, vague or fuzzy terms, hence formal frameworks for modeling and verifying such requirements are desirable. The Fuzzy If–Then rules have been used for imprecise requirements representation, but verifying their functional properties still needs new methods. In this paper, we propose a refinement-based modeling approach for specification and verification of such requirements. First, we introduce a representation of imprecise requirements in the set theory. Then we make use of Event-B refinement providing a set of translation rules from Fuzzy If–Then rules to Event-B notations. After that, we show how to verify both safety and eventuality properties with RODIN/EventB. Finally, we illustrate the proposed method on the example of Crane Controller.Hong Anh Lelehonganh@humg.edu.vnNakajima ShinNinh Thuan Truongthuantn@vnu.edu.vn2016-11-24T08:58:17Z2016-11-24T08:58:17Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1942This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/19422016-11-24T08:58:17ZA Novel Credit Scoring Prediction Model based on Feature Selection Approach and Parallel Random ForestBackground/Objectives: This article presents a method of feature selection to improve the accuracy and the computation speed of credit scoring models. Methods/Analysis: In this paper, we proposed a credit scoring model based on parallel Random Forest classifier and feature selection method to evaluate the credit risks of applicants. By integration of Random Forest into feature selection process, the importance of features can be accurately evaluated to remove irrelevant and redundant features. Findings: In this research, an algorithm to ...Van Sang HaHa Nam Nguyennamnh@vnu.edu.vnDuc Nhan Nguyen2016-11-21T06:35:24Z2016-11-21T06:35:24Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1897This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18972016-11-21T06:35:24ZMobile Online Activity Recognition System Based on Smartphone SensorsIn this paper, we propose an efficient and flexible framework for activity recognition based on smartphone sensors. We develop a mobile application that integrates data collection, training and recognition, feedback monitoring. This system allows user smartphones are randomly placed in any position and at any direction. In the proposed framework, a set of power based and frequency-based features is extracted from sensor data. Then, we deploy Random Forest, Naïve Bayes, K-Nearest Neighbor (KNN), Support Vector Ma-chine (SVM) classification algorithms for recognizing a set of user activities. Our framework dynamically takes into account real-time user feedbacks to increase the prediction accuracy. Our framework will be able to apply for intelligent mo-bile applications. A number of experiments were carried out to show the high ac-curacy of the proposed framework for detecting user activities when walking or driving a motorbike.Dang Nhac LuThu Trang NguyenThi Thu Trang NgoThi Hau Nguyennguyenhau@vnu.edu.vnHa Nam Nguyennamnh@vnu.edu.vn2016-11-15T02:44:31Z2017-01-05T02:42:46Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1890This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18902016-11-15T02:44:31ZCải tiến phương pháp lặp vi phân Born bằng đặt ngưỡng giới hạnBài báo đề xuất giải pháp cải tiến phương pháp lặp vi phân Born (Distorted Born Iterative Method - DBIM), là phương pháp cho phép phát hiện sớm ung thư qua kỹ thuật siêu âm cắt lớp, bằng cách đặt ngưỡng giới hạn đối với tín hiệu đo áp suất tán xạ nhằm rút ngắn thời gian tính toán tái tạo ảnh siêu âm. Kết quả mô phỏng cho thấy giải pháp này đã rút ngắn được thời gian tính toán tái tạo ảnh trong khi vẫn đảm bảo chất lượng hình ảnh.Hoang Tuan Hiep Vuhoanghiepbk@gmail.comMinh Chinh Truongtmchinh@gmail.comDuc Tan Trantantd@vnu.edu.vn2016-11-14T02:31:17Z2016-11-14T02:31:17Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1883This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18832016-11-14T02:31:17ZLearning to Filter User Explicit Intents in Online Vietnamese Social Media TextsToday, Internet users are much more willing to express themselves on online social media channels. They commonly share their daily activities, their thoughts or feelings, and even their intention (e.g., buy a camera, rent an apartment, borrow a loan, etc.) about what they plan to do on blogs, forums, and especially online social networks. Understanding intents of online users, therefore, has become a crucial need for many enterprises operating in different business areas like production, banking, retail, e–commerce, and online advertising. In this paper, we will present a machine learning approach to analyze users’ posts and comments on online social media to filter posts or comments containing user plans or intents. Fully understanding user intent in social media texts is a complicated process including three major stages: user intent filtering, intent domain identification, and intent parsing and extraction. In the scope of this study, we will propose a solution to the first one, that is, building a binary classification model to determine whether a post or comment carries an intent or not. We carefully conducted an empirical evaluation for our model on a medium-sized collection of posts in Vietnamese and achieved promising results with an average accuracy of more than 90%.Thai Le LuongThi Hanh TranQuoc Tuan TruongThi Minh Ngoc TruongThi Thu PhiXuan Hieu Phanhieupx@vnu.edu.vn2016-10-31T02:29:49Z2017-01-05T02:41:15Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1881This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18812016-10-31T02:29:49ZMonitoring of Landslides in Mountainous Regions based on FEM Modelling and Rain Gauge MeasurementsVietnam is a country heavily influenced by climate change. The effect of climate change leads to a series of dangerous phenomena, such as landslides. Landslides occur not only in the mountainous province, but also in Delta provinces, where hundreds of landslides are reported annually in the North-Western provinces of Vietnam. These events have catastrophic impact to the community as well as the economy. In mountainous areas, the conditions for landslides to occur are met frequently, especially after heavy rains or geological activity, causing harm to the community as well as damaging or destroying much needed infrastructure and key transport routes. However, in Vietnam, investment in mountainous regions has been often lower than in urban areas. The meteorology monitoring and forecasting systems are ill equipped and overloaded, so they cannot deliver earlier and more accurate forecasts for complex weather events, unable to provide timely warnings. It can be seen that in countries that landslide often occur, researchers have been trying to develop low cost and efficient landslide detection system. This paper precisely addressed the problems mentioned, by designing and implementing an efficient and reliable Landslide Monitoring and Early Warning (LMnE) system based on the 3G/2G mobile communication system, and a rain gauge at the field site along with a carefully FEM (finite element method) simulation using the rain density information on the server. The system uses advanced processing algorithms combining obtained data at the central station.Quoc Anh Giangianquocanh@gmail.comDinh Chinh Nguyenchinhnd@vnu.edu.vnDuc Nghia Trannghiatd@gmail.comDuc Tan Trantantd@vnu.edu.vn2016-10-31T02:28:08Z2016-10-31T02:28:08Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1880This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18802016-10-31T02:28:08ZCharacterizing Stochastic Errors of MEMS-Based Inertial SensorsThank to strong grow of MicroElectroMechanicalSystem (MEMS) technology, high performance and small size sensors are widely used in many areas such as landslide, navigation, mobile phones, etc. However, there are several kinds of errors are still existing in MEMS based sensors that need a carefully analyzing and calibration. By each year, the performances of commercial sensors are also improved. In this paper, we focused on characterizing the stochastic errors of accelerometers and gyroscopes integrated with a latest smart phone of Apple Inc. Iphone6+. The MP67B is a custom version of the InvenSense 6-Axis device (3-Axis gyroscope and 3-Axis accelerometer) made for Apple. This research will play an important step to decide whether we can create an Inertial Navigation System (INS) in the same device (i.e. the smart phone, the users do not need to equip a single device for positioning application). The Allan variance method is exploited to analyze the stochastic errors in these sensors. Experiments proved that the main sources of errors in these sensors are white noises. The Iphone5 can operate as a low-cost solution of positioning and navigation device.Van Tang Phamphamvantang@gmail.comDuc Tan Trantantd@vnu.edu.vnDuc Trinh Chutrinhcd@vnu.edu.vn2016-10-27T07:09:11Z2016-10-27T07:09:11Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1878This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18782016-10-27T07:09:11ZAn Online Local Boundary Detection and Classification Algorithm for Networked Multi-Robot SystemsWe present an online boundary classification error detection algorithm to improve accuracy of the original
distributed boundary detection algorithm for networked multirobot systems. It is a fully decentralized method based on the geometric approach allowing to suppress boundary errors without recursive process and global synchronization. The accuracy of the ration of correctly identified robots over the total number of robots reaches 100%. We have demonstrated the effectiveness of this boundary detection algorithm in both simulation and real-world environment.Duy Hung Phamhungpd@vnu.edu.vnQuang Vinh Tranvinhtq@vnu.edu.vnTrung Dung Ngo2016-10-26T04:40:23Z2016-10-26T04:40:40Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1877This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18772016-10-26T04:40:23ZOn the Implementation of Chaotic Compressed Sensing for MRIMinh Chinh TruongLinh Trung Nguyenlinhtrung@vnu.edu.vnDuc Tan Trantantd@vnu.edu.vn2016-09-04T11:21:31Z2016-09-04T11:21:31Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1868This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18682016-09-04T11:21:31ZA trace clustering solution based on using the distance graph modelQuang Thuy Hathuyhq@vnu.edu.vnHong Nhung BuiTri Thanh Nguyenntthanh@vnu.edu.vn2016-09-04T11:19:17Z2016-09-04T11:19:17Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1867This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18672016-09-04T11:19:17ZA study on fitness representation in Genetic
ProgrammingThi Thuong PhamXuan Hoai NguyenTri Thanh Nguyenntthanh@vnu.edu.vn2016-09-04T11:16:45Z2016-09-04T11:16:45Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1862This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18622016-09-04T11:16:45ZDetecting user status from smartphone sensor dataDue to the high increment in usage and built-in advanced technology of smartphones, human activity recognition relying on smartphone sensor data has become a focused research area. In order to reduce noise of collected data, most of previous studies assume that smartphones are fixed at certain positions. This strategy is impractical for real life applications. To overcome this issue, we here investigate a framework that allows detecting the status of a traveller as idle or moving regardless the position and the direction of smartphones. The application of our work is to estimate the total energy consumption of a traveller during a trip. A number of experiments have been carried out to show the effectiveness of our framework when travellers are not only walking but also using primitive vehicles like motorbikes.Thu-Trang NguyenThi-Hau NguyenHa-Nam NguyenDuc-Nhan NguyenGyooSeok Choi2016-09-02T16:16:27Z2017-01-17T02:18:49Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1873This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18732016-09-02T16:16:27ZDesign and Implementation of a Hybrid Switching Router for the Reconfigurable Network-on-ChipKiem Hung Nguyenkiemhung@vnu.edu.vnXuan Tu Trantutx@vnu.edu.vn2016-09-02T16:13:11Z2017-01-17T02:19:31Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1872This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18722016-09-02T16:13:11ZFuzzy-Logic based Low Power Solution for Network-on-Chip ArchitecturesHai Phong Phanhaiphongphan@gmail.comXuan Tu Trantutx@vnu.edu.vn2016-09-02T16:00:49Z2016-09-02T16:00:49Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1869This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18692016-09-02T16:00:49ZA complete fingerprint matching algorithm on GPU for a large scale identification systemHong Hai LeNgoc Hoa Nguyenhoa.nguyen@vnu.edu.vnTri Thanh Nguyenntthanh@vnu.edu.vn2016-08-29T09:59:42Z2016-08-29T09:59:42Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1841This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18412016-08-29T09:59:42ZTrực quan hoá dữ liệu trạng thái giao thông trên nền WebPhuong Hanh Duhanhdp@vnu.edu.vnBa Duy Vuduyvb@vnu.edu.vnNgoc Hoa Nguyenhoa.nguyen@vnu.edu.vn2016-08-29T08:58:39Z2016-08-29T08:58:39Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1838This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18382016-08-29T08:58:39ZUsing Local Weather and Geographical Information to Predict Cholera Outbreaks in Hanoi, VietnamIn 2007, repeated outbreaks of cholera in Hanoi have raised
the need to have up-to-date evidence on the impact of factors on cholera epidemic, which is essential for developing an early warning system. We have successfully built models to predict cholera outbreaks in Hanoi from
2001 to 2012 using Random Forests method. We found that geographical factors - the number of cholera cases of a district of interest and its neighbours - are very important to predict accurately cholera cases besides the weather factors. Among weather factors, temperature and
relative humidity are the most important. We also found that
prediction accuracy of our models, measured in adjusted coefficient of determination, will decrease by 0.0076 if prediction length increases by one day.Hai Chau Nguyenchaunh@vnu.edu.vnThi Ngoc Anh Le2016-07-22T03:41:46Z2016-07-22T03:41:46Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1785This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/17852016-07-22T03:41:46ZString distance for automatic image classificationThe Bag-of-visual Words (BOW) model has recently become the most popular representation to depict image content. It has proven to be quite effective for many multimedia and vision applications, especially for object recognition and scene classification or automatic image annotation. This model however ignores the spatial layout of features within images, which is yet discriminative for category classification. In this paper, we present a novel approach based on string matching to take into account geometric correspondences between images and facilitate category recognition. First, we propose to represent images as strings of histogram second, we introduce a new string distance in the context of image comparison. This distance automatically identifies local alignments between sub image regions and allows merging groups of similar sub-regions. Experiments on several dataset such as Scene-15, Caltech-101 and Pascal 2007 show that the proposed approach outperforms the classical BOW method and is competitive with state-of-the art techniques for image classification.Thinh Nguyen Honghongthinh.nguyen@vnu.edu.vnHa Le Vuhalv@vnu.edu.vnCecile Baratcecile.barat@univ-st-etienne.frChristophe Ducottetducottet@univ-st-etienne.fr2016-07-22T03:41:18Z2016-07-22T03:41:18Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1783This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/17832016-07-22T03:41:18ZCorona based air-flow using parallel discharge electrodesAbstract A novel air-flow generator based on the effect of ion wind has been developed by the simultaneous generation of both positive and negative ions using two electrodes of opposite polarity placed in parallel. Unlike the conventional unipolar-generators, this bipolar configuration creates an ion wind, which moves away from both electrodes and yields a very low net charge on the device. The electro-hydrodynamic behaviour of air-flow has been experimentally and numerically studied. The velocity of ion wind reaches values up to 1.25 m/s using low discharge current 5 μA with the kinetic conversion efficiency of 0.65 and the released net charge of -30 fA, 8 orders of magnitude smaller compared with the discharge current. Due to easy scalability and low net charge, the present configuration is beneficial to applications with space constraints and/or where neutralized discharge process is required, such as inertial fluidic units, circulatory flow heat transfer, electrospun polymer nanofiber to overcome the intrinsically instability of the process, or the formation of low charged aerosol.Van Thanh DauThien Xuan DinhBui Thanh Tungtungbt@vnu.edu.vnCanh-Dung TranHoa Thanh PhanTibor Terebessy2016-07-22T03:41:10Z2016-07-22T03:41:10Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1782This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/17822016-07-22T03:41:10ZSelection of Appropriate Number of CRs in Cooperative Spectrum Sensing over Suzuki FadingWith the rapid development of wireless communications, the radio spectrum is becoming scarce. However, researchers have shown that many portions of licensed spectrum unused for significant periods of time. Recently, cognitive radio has been proposed as a very effective mechanism which allows Cognitive Radio Users (CRs) to utilize the idle unused licensed bands. The main challenge for a CR is to detect the existence of Primary User (PU) in order to minimize the interference to it. In this paper, we study the cooperative spectrum sensing under Suzuki composite fading channel which is the mixture of Rayleigh fading channel and Log-normal shadowing channel. Besides, we also concentrate on finding the minimum number of CRs taking part in the collaborative spectrum sensing to avoid the overhead to the network but still guarantee the sensing performance through calculations and numerical results. Our analysis and simulation results suggest that collaboration may improve sensing performance significantly.Thi Thai Mai Dinhdttmai@vnu.edu.vnLong Nguyen Thanhlongnt@gmail.comTuan Nguyen Quoctuannq@vnu.edu.vn2016-07-22T03:40:45Z2016-07-22T03:40:45Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1781This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/17812016-07-22T03:40:45ZAdaptive Scalable Video Coding: a HEVC based Framework Combining the Predictive and Distributed ParadigmsThe emerging Scalable HEVC (SHVC) video coding standard provides an efficient solution for transmission of video over heterogeneous and time dynamic networks, terminals, and usage environments. The encoding complexity and the error sensitivity associated to the efficient HEVC coding tools adopted in SHVC make this scalable codec less attractive to some emerging applications such as video surveillance, visual sensor network, and remote space transmission where these requirements are critical. To address the requirements of these application scenarios including scalability, this paper proposes a novel HEVC based framework offering quality scalability on top of a HEVC compliant base layer while appropriately combining the predictive and distributed coding paradigms. To achieve the best enhancement layer compression efficiency, two novel coding tools are proposed, notably a machine learning based side information creation mechanism and an adaptive correlation modeling process. The experimental results reveal that the rate-distortion performance of the proposed DSVC-HEVC solution outperforms the relevant alternative coding solutions, notably by up to 52.9% and 23.7% BD-rate gains regarding the HEVC-Simulcast and SHVC standard solutions, respectively, for an equivalent prediction configuration, while achieving a lower encoding complexity.Xiem Hoang Vanxiemhoang@vnu.edu.vnJoão Ascensojascenso@gmail.comFernando Pereirafpereira@gmail.com2016-07-22T03:40:37Z2016-07-22T03:40:37Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1779This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/17792016-07-22T03:40:37ZNGHIÊN CỨU PHÁT TRIỂN THIẾT BỊ ĐO MƯA HỖ TRỢ CẢNH BÁO TRƯỢT LỞ ĐẤTTrượt lở đất là một trong những thảm hoạ thiên nhiên rất nghiêm trọng, gây thiệt hại lớn về người và tài sản. Vì thế, những nỗ lực nghiên cứu và triển khai cảnh báo, phòng ngừa trượt đất đã được thực hiện ở các quy mô khác nhau. Một trong các điều kiện kích hoạt trượt lở đất đó là do lưu lượng mưa tăng cao một cách đột biến. Báo cáo này tập trung vào xây dựng một hệ cảnh báo dựa trên việc xác định lưu lượng mưa tại các khu vực có khả năng xảy ra trượt lở đất ở khu vực Tây Bắc – Việt Nam. Hệ đo mưa được xây dựng dựa trên việc sử dụng cảm biến đo khoảng cách và bộ vi điều khiển phù hợp. Ngưỡng cảnh báo được xây dựng dựa trên phương pháp thống kê lưu lượng mưa (theo khu vực lắp đặt) trong nhiều năm để đưa ra cảnh báo kịp thời. Hệ thống đã được xây dựng thành công và đã được thử nghiệm tại khu vực tỉnh Hà Giang của Việt Nam bước đầu hoạt động rất tốt.Chinh Nguyen Dinhchinhnd@vnu.edu.vnAnh Gian Quocgianquocanh@gmail.comQuy Mai The Phumaithephuquy@gmail.comLinh Nguyen Tuanlinhnt@gmail.comAnh Nguyen Tienanhnt007@gmail.comTan Tran Ductantd@vnu.edu.vn2016-07-22T03:40:20Z2016-07-22T03:40:20Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1826This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18262016-07-22T03:40:20ZMicrofluidic Impedance Biosensors For Monitoring A Single And Multiple Cancer Cells In Anticancer Drug TreatmentsIn this work, we present a novel microfluidic impedance biosensor chip for trapping both a single and multiple cancer cells and monitoring their response to the anticancer drug treatment. By designing different sizes of working microelectrodes together with the V-shaped cell capture structures, a single or multiple cells are trapped on the microelectrodes surfaces. In addition, by utilizing the passive pumping method, cells can be trapped and positioned inside the microchannels without the need of using the outer micro pump or syringe. The impedance change induced by the response of cells to the anticancer drug Cisplatin treatment was successfully recorded. The proposed biosensor chip has a great potential for applications in cancer cell research, drug screening, and quantification of cancer cells from various tumor stages. The results of this study open potential research collaborations about development of cost-effective devices and lab-on-chips for early disease detection , studies of cancerous cells and their response to anti-cancer drugs to optimize cancer treatments, charac-terisation of mechanical properties of cells, new drug delivery mechanisms, and micro and nano manufacturing .Anh Nguyen TienTien Nguyen VanTan Tran Ductantd@vnu.edu.vnToan Nguyen VanHieu Le ChiQuoc Le Hoai2016-07-11T12:40:48Z2016-07-11T12:41:42Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1811This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18112016-07-11T12:40:48ZMEH-PPV: PCBM Solution for Screen-printing Technique in Polymer Solar Cell FabricationThe fabrication and property characterization of bulk heterojunction photoactive layer made of blend of poly[2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) and (6,6)-phenyl C61 butyric acid methyl ester (PCBM) and fabricated by screen-printing technique was carried out. Effects of the photoactive solid concentration, temperatures at 15, 25 and 35°C and shear rate ranging from 100-104 sec–1 on the viscosity was investigated and shows that 1, 3 and 5% solid concentrated solutions are possible for using as ink in this technique in term of rheological property. Thickness of the films fabricated from different solid concentrated solutions at different print speed was measured and show a dependency of film thickness on print speed as well as exponential law dependence on solid concentration of the solution. Surface morphology and absorption coefficient of the films was also carried out and confirms that the films formed by the screen printer is well-adapted for fabricate photovoltaic devices.Van Chau Dinhdinhchau@vnu.edu.vnVan Thuong Dinh2016-07-11T12:28:23Z2016-12-10T10:59:26Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1803This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/18032016-07-11T12:28:23ZLight Absorption and Luminescence Quenching Properties of Hybrid Bulk Heterojunction Materials Based on the Blend Conducting PolymersWe have investigated the enhancement absorption light and luminescence quenching properties of the hybrid bulk heterojunction systems which were fabricated using poly[2-methoxy-5-(2-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV); poly(3-hexylthiophene) (P3HT); fullerene derivative 1-(3-methoxycarbonyl) propyl-1-phenyl-[6,6] C61 (PCBM) and TiO2 nanocrystals. The optimized material showed a broad absorption in the region of 350 to 670 nm and the luminescence quenching higher 85%. The obtained results provide further insight into photophysics of the heterojunction system and device performance improvement by using this system as an active layer.Phuong Hoai Nam Nguyennamnph@vnu.edu.vnNang Dinh Nguyendinhnn@vnu.edu.vnThu Ha LeTrinh Tung Ngo2016-06-09T09:06:24Z2016-06-09T09:06:24Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1770This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/17702016-06-09T09:06:24ZA Scalable, Decentralised Large-Scale Network of Mobile Robots for Multi-target TrackingA scalable, decentralised large-scale network of mobile robots for multi-target tracking is addressed in this paper. The decentralised control is originally built up by behavioural control but upgraded with decentralised robot control for connectivity maintenance and decentralised connectivity control for hierarchical connectivity removal, allowing the network expansion for tracking and occupying spatially distributed targets. The multi-target tracking algorithm guarantees that the mobile robots reach targets at very high efficiency, while at least an interconnectivity network connecting all the mobile robots is preserved for information exchange. The Monte Carlo simulation results illustrate characteristics of the decentralised control as well as its scalability through several experimental scenarios.Duy Hung Phamhungpd@vnu.edu.vnQuang Vinh Tranvinhtq@vnu.edu.vnTrung Dung Ngontdung@gmail.com2016-06-09T02:15:48Z2016-06-09T02:15:48Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1766This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/17662016-06-09T02:15:48ZFast adaptive PARAFAC decomposition algorithm with linear complexityWe present a fast adaptive PARAFAC decomposition algorithm with low computational complexity. The proposed algorithm generalizes the Orthonormal Projection Approximation Subspace Tracking (OPAST) approach for tracking a class of third-order tensors which have one dimension growing with time. It has linear complexity, good convergence rate and good estimation accuracy. To deal with large-scale problems, a parallel implementation can be applied to reduce both computational complexity and storage. We illustrate the effectiveness of our algorithm in comparison with the state-of-the-art algorithms through simulation experiments.Viet Dung NguyenKarim Abed-MeraimLinh Trung Nguyenlinhtrung@vnu.edu.vn2016-06-09T02:09:03Z2016-06-09T02:09:03Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1765This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/17652016-06-09T02:09:03ZCommunication-Aware Route Selection in Wireless Sensor NetworksWe consider the problem of optimal route selection for wireless sensor network in the presence of path loss, multipath fading, interference, and environmental noise. The communication-aware route selection strategy is proposed by incorporating realistic communication model portraying the underlying dynamics of wireless link. The link quality is characterized by the probability of successfully received packets over a communication link, so-called reception probability. We utilize reception probability as a metric for communication quality-oriented route selection and to compare its performance with the conventional metrics, i.e., Hop count and Euclidean distance. The simulation results demonstrate that reception probability-based route selection provides optimal end-to-end throughput in wireless sensor networks.Adnan Fidaf.adnan@gmail.comDuy Hung Phamhungpd@vnu.edu.vnNor Jaidi Tuahtn.jaidi@gmail.comTrung Dung Ngontdung@gmail.com2016-06-08T06:19:06Z2016-06-08T06:19:06Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1764This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/17642016-06-08T06:19:06ZJet flow generation in a circulatory miniaturized systemIn this paper, we report on a miniaturized device that can generate multiple jet flows circulated in a confined system. The device has a flow network comprised of four symmetrical working chambers connected with a pump chamber. The pump chamber is actuated by a PZT diaphragm. The flows in the device are studied by a computational fluid dynamics simulation and experimental measurements. The numerical simulation is carried out with programmable open source OpenFOAM, where the vibration of the PZT diaphragm is modeled with a newly developed boundary condition. Flow inside the device is verified by two hotwires embedded in each working chamber. It was confirmed that the flows generated in the four sensing chambers were almost identical. The performance of the device can be customized either by fluidic parameters, such as the driving voltage on the diaphragm, or by heat transfer processes, such as heating current of the hotwire or by alternating the gas media. The device is robust, ready-to-use and minimal in size. These are important features that can contribute to the development of multi-axis fluidic inertial sensors, fluidic amplifiers, gas mixing, coupling and analysis.Van Thanh Dauvandt@gmail.comThien Xuan Dinhthienxd@gmail.comThanh Tung Buitungbt@vnu.edu.vn2016-06-03T01:45:03Z2016-06-03T01:45:03Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1640This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/16402016-06-03T01:45:03ZIdentifying User Intents in Vietnamese Spoken Language Commands and Its Application in Smart Mobile Voice InteractionThi Lan NgoVan Hop Nguyenhopnv_57@vnu.edu.vnThi Hai Yen Vuongyenvth_57@vnu.edu.vnThac Thong NguyenThi Thua NguyenBao Son Phamsonpb@vnu.edu.vnXuan Hieu Phanhieupx@vnu.edu.vn2016-06-03T01:41:48Z2016-06-03T01:41:48Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1639This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/16392016-06-03T01:41:48ZNamed Entity Recognition for Vietnamese Spoken Texts and Its Application in Smart Mobile Voice InteractionPhuong Nam TranVan Duc TaQuoc Tuan TruongQuang Vu DuongThac Thong NguyenXuan Hieu Phanhieupx@vnu.edu.vn2016-06-02T05:30:43Z2016-06-02T05:30:43Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1638This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/16382016-06-02T05:30:43ZSentiment Analysis and User Similarity for Social Recommender System: An Experimental StudyThi Ngan PhamThi Hong Vuonghongvt_57@vnu.edu.vnThi Hoai ThaiMai Vu Tranvutm@vnu.edu.vnQuang Thuy Hathuyhq@vnu.edu.vn2016-06-02T03:58:16Z2016-06-02T03:58:16Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1636This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/16362016-06-02T03:58:16ZAn Experimental Study on Cholera Modeling in HanoiNgoc Anh Thi LeThi Oanh NgoHuyen Trang Thi LaiHoang Quynh Lelhquynh@gmail.comHai Chau Nguyenchaunh@vnu.edu.vnQuang Thuy Hathuyhq@vnu.edu.vn2016-05-31T02:26:22Z2016-05-31T02:26:22Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1581This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15812016-05-31T02:26:22ZAbsolute pressure sensing with bipolar corona discharge: Design, simulation and experimental validationIn this paper we present, for the first time, a reliable cost-effective absolute pressure sensor based on a novel bipolar corona system, which monitors pressure by producing both polarities of corona discharge simultaneously. The unique setup increases sensitivity and stability of the sensor. Systematical design study, numerical simulation and experiment of five prototypes acquired consistent results. With sub-microampere operating current, the sensors have temperature-independent sensitivity and good repeatability.Thanh Tung Buitungbt@vnu.edu.vnDan Vanv.dan@gmail.comXuan Thien Dinhtxuan.dinh@gmail.comTerebessy Tibort.terebessy@gmail.comThanh Hoa Phanp.hoa@gmail.com2016-05-31T02:24:44Z2016-05-31T02:24:44Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1580This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15802016-05-31T02:24:44ZCopper-Filled Through-Silicon Vias with Parylene-HT LinerOrganic low-$k$ materials have been considered in the literature for satisfying the requirements of lowering the dielectric constant of the dielectric layer to decrease the problem of signal delay, lower power consumption, and to reduce cross talk between the neighboring paths, and lowering the fabrication temperature budget. In this paper, the feasibility of using Parylene-HT as a low-temperature deposition, high-uniformity coverage low-dielectric liner for copper-filled through-silicon vias (TSVs) in 3-D integration is investigated. In particular, the capability of embedding Parylene-HT in via-last fabrication process is validated through the demonstration of 100-μ m-depth bottom-up copper-filled TSVs. TSVs with Parylene-HT as a liner were realized through vias etching, parylene vapor deposition, and copper electroplating processes. The Parylene-HT deposition and copper electroplating processes were implemented at room temperature, such that thermal-related issue would be avoided and device reliability would be enhanced. The insulation function of the Parylene-HT liner of the fabricated TSVs was characterized. Capacitance of 0.164 pF/TSV and leakage current density of 22 pA/cm2 at a field of 0.25 MV/cm were obtained through the measurement of the TSV arrays. The obtained results reveal the possibility of using such a high potential parylene in low-temperature budget 3-D integration applications.Thanh Tung Buitungbt@vnu.edu.vnWatanabe NaoyaN.Watanabe@gmail.comCheng XiaojinX.Cheng@gmail.comKato FumikiF.Kato@gmail.comKikuchi KatsuyaK.Kikuchi@gmail.comAoyagi MasahiroM.Aoyagi@gmail.com2016-05-28T08:38:10Z2016-05-28T08:38:10Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1660This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/16602016-05-28T08:38:10ZMultiple Description Coding of Motion Fields Using Wyner-Ziv Scheme for Robust Video TransmissionKang Sun ChoiTrieu Duong Dinhduongdt@vnu.edu.vnQuang Dieu TranThanh Ha Leltha@vnu.edu.vn2016-05-28T03:57:33Z2017-01-06T09:25:05Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1689This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/16892016-05-28T03:57:33ZImproving SHVC Performance with a Joint Layer Coding ModeThe growing need for a powerful scalable video coding engine targeting the heterogeneous landscape of network, devices, and consumption environments has led to the development of the Scalable High Efficiency Video Coding (SHVC) standard, an extension of the High Efficiency Video Coding (HEVC) standard. To improve the SHVC compression efficiency, this paper proposes a novel joint layer coding mode to be integrated in the SHVC codec. In the proposed coding mode, the base layer (BL) and enhancement layer (EL) decoded information are linearly combined at the pixel level to create an additional coding mode. To fuse the BL and EL driven predictions, a weighting term is defined to indicate the contributions of each of them for the final joint layer prediction. To reach high adaptability, these weights are computed at pixel level in the prediction unit. Moreover, to achieve the highest compression efficiency, the proposed joint layer coding mode is adaptively selected using a rate distortion optimization (RDO) mechanism. Experiments conducted for a rich set of test conditions have shown that significant compression efficiency gains can be achieved with the proposed joint layer coding mode, notably up to 4.3 % in BD-Rate savings regarding the standard SHVC quality scalable codec.Van Xiem Hoangxiemhoang@vnu.edu.vnJoao AscensoA.Joao@gmail.com2016-05-27T03:16:14Z2016-05-27T03:17:34Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1760This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/17602016-05-27T03:16:14ZMô hình chia sẻ tài nguyên học liệu trực tuyếnBài báo giới thiệu mô hình chia sẻ tài nguyên trực tuyến cho phép cộng đồng người sử dụng tạo lập và chia sẻ các tài liệu học tập và giảng dạy, từ đó hình thành một kho học liệu mở với học liệu tuân thủ chuẩn scorm, dễ dàng tích hợp vào các hệ thống Learning Management System. Bên cạnh đó, chúng tôi cũng trình bày một số chức năng chính của phần mềm ConnectData do chúng tôi xây dựng để thử nghiệm mô hình. Kết quả thăm dò khi triển khai phần mềm ConnectData để thử nghiệm mô hình đã nhận được ý kiến phản hồi tích cực từ phía người sử dụng.Viet Anh Nguyenvietanh@vnu.edu.vnManh Tien HoangHoa Huy Nguyen2016-05-27T03:13:37Z2016-05-27T03:14:39Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1757This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/17572016-05-27T03:13:37ZFabrication and characterization of PZT string based MEMS devicesString based MEMS devices recently attract world technology development thanks to their advantages over cantilever ones. Approaching to this direction, the paper reports on the micro-fabrication and characterization of free-standing doubly clamped piezoelectric beams based on heterostructures of Pd/FeNi/Pd/PZT/LSMO/STO/Si. The displacement of strings is investigated in both static and dynamic mode. The static response exhibits a bending displacement as large as 1.2 μm, whereas the dynamic response shows a strong resonance with a high quality factor of 40 depending on the resonant mode at atmospheric pressure. These findings are comparable with those observed in large dimension membrane and cantilever based MEMS devices, which exhibit high potentials in variety of sensor and resonant actuator applications.Thi Huong Giang Dogiangdth@vnu.edu.vnHuu Duc Nguyenducnh@vnu.edu.vnG. AgnusT. MaroutianPhilippe Lecoeur2016-05-26T05:42:45Z2016-05-26T05:44:01Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1746This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/17462016-05-26T05:42:45ZEfficient Region-of-Interest Based Adaptive Bit Allocation for 3D-TV Video Transmission over NetworksDue to characteristics of human visual system (HVS), people usually focus more on a specific region named region-of-interest (ROI) of a video frame, rather than watch the whole frame. In addition, ROI-based video coding can also help to effectively reduce the number of encoding bitrates required for video transmission over networks, especially for the 3D-TV transmissions. Therefore, in this work, we propose a novel ROI-based bit allocation (BA) method which can adaptively extract and increase the visual quality of ROI while saving a huge number of encoding bitrates for video data. In the proposed method, we first detect and extract ROI based on the depth information obtained from 3D-TV video coding sequences. Then, based on the extracted ROI, a novel BA scheme is performed to solve the rate-distortion (R-D) optimization problem, in which the higher priority bitrates are adaptively assigned to ROI while the total encoding bitrates of video frames are kept satisfying all constraints required by the R-D optimization. Experimental results show that the proposed method provides much better higher peak signal-to-noise ratio (PSNR) as compared to other conventional BA methods.Nam Thanh Phamnampt@gmail.comKhuong Duy Vuduykv@gmail.comDuong Trieu Dinhđuongt@vnu.edu.vnHa Thanh Lethanhha@vnu.edu.vn2016-05-26T05:37:57Z2016-05-26T05:38:39Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1747This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/17472016-05-26T05:37:57ZImplicit Feedback Mechanism to Manage User Profile Applied in Vietnamese News Recommender SystemThe appearance of a vast array of online newspapers makes appropriate news recommendation for users become critically important. A number of researches in this area have been conducted in recent years. This paper presents the Vietnamese content-based news recommender system. Based on information about news stories that users have read and given feedback, the system can automatically determine news stories that users may want to read later. The center of the system is a hybrid user profile which can diversely model news reading features of individual users thanks to a combination of short-term and long-term information models along with self-description. The paper also introduces and evaluates a mechanism for implicit feedback. After installing the system and conducting several experiments, as well as collecting feedback from users, it is shown that the system is relatively adaptable to users and can recommend appropriate news with a high degree of accuracy, which significantly increases the effectiveness of gathering information compared to traditional news reading.Thac Huy NguyenThe Chuan DoViet Anh Nguyenvietanh@vnu.edu.vn2016-05-25T03:45:44Z2016-05-25T03:52:06Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1687This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/16872016-05-25T03:45:44ZNonlinear thermal dynamic response of shear deformable FGM plates on elastic foundationsDinh Duc Nguyenducnd@vnu.edu.vnHuy Bich DaoHong Cong Pham2016-05-25T03:31:02Z2016-05-25T03:33:23Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1583This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15832016-05-25T03:31:02ZA novel mixing surface acoustic wave device for liquid sensing applicationsThis paper presents a novel mixing surface acoustic wave (M-SAW) device using multiple Aluminum (Al) interdigital transducer (IDT) layers for liquid sensing applications. The stronger mechanical wave beam generated by the multiple input-IDT layers on the thin film (1 μm) Aluminum Nitride (AlN), consists of different-phase acoustic waves that can travel through a liquid medium. In contrast to the whole signal leaking into liquid medium as in typical SAW devices, the signal obtained at the receiver of the M-SAW device only has a decline in the Rayleigh component. The experimental results show that it is possible to interact with the liquid medium placed on the surface and extract information about the liquid volume based on the phase change. Phase shifts of -16.35°, -11.23°, -4.84°, and -0.86° are obtained for different volumes of demi-water after 10 seconds, 2, 4 and 5 minutes of vaporization, respectively.Thu Hang Buihangbt@vnu.edu.vnMorana Brunob.morana@gmail.comScholtes Tomt.scholtes@gmail.comDuc Trinh Chutrinhcd@vnu.edu.vnSarro Pasqualinap.sarro@gmail.com2016-05-25T03:06:17Z2016-05-25T03:09:42Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1578This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15782016-05-25T03:06:17ZFabrication and stress analysis of annular-trench-isolated TSVThe large mismatches among the coefficients of thermal expansion (CTE) of the metal via, insulator liner, and Si substrate of the through-silicon via (TSV) induce thermal stresses within and around the TSV during thermal-cycled fabrication processes. Reduction of thermal stress in the Si substrate is important for minimizing the deviations in the device characteristics. An annular-trench-isolated (ATI) structure was proposed for the TSV to solve the thermal issues, which occur during the three-dimensional (3D) integrated circuit (IC) integration, by stress redistribution. The concept of ATI TSV is based on retaining a Si-ring between the metal core and insulator layer during the fabrication process. We realized the ATI TSV using a via-last fabrication approach, with two deep silicon etching processes (Bosch processes) for the insulator layer and the metal core. Parylene-HT was utilized as the insulator to achieve high uniformity. With a vacuum-assisted filling system, the vias were filled with a solder material. ATI TSVs with diameters of 10 μm and 2-μm-thick Parylene-HT insulation layers were demonstrated. Studies on the thermal stress levels of the ATI TSV were carried out by finite-element method (FEM) simulation, along with comparisons with regular and annular TSVs. We revealed that the ATI TSV shows lower thermal stresses in the Si substrate than the regular and annular TSVs. The ATI TSV is a possible candidate for 3D IC integration with stress-sensitive devices.Wei FengThanh Tung Buitungbt@vnu.edu.vnNaoya WatanabeHaruo ShimamotoMasahiro AoyagiKatsuya Kikuchi2016-05-25T03:03:45Z2016-05-25T03:05:08Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1577This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15772016-05-25T03:03:45ZInvestigating the performance of expert system in a multistage system for automatic detection of epileptic spikesAn automatic detection system for epileptic spikes is used as an assistive tool for epileptic analysis and diagnosis using electroencephalogram (EEG). Our system consists of four stages: preprocessing, feature extraction classification and expert system. In this paper, we concern to the performance of 4th stage (expert system) to choose the best threshold for detecting epileptic spikes efficiently. The proposed method is verified by experimental data acquired from ten patients (for training) and four patients (for testing).Duc Tan Trantantd@vnu.edu.vnLinh Trung Nguyenlinhtrung@vnu.edu.vn2016-05-24T01:36:58Z2016-12-31T14:17:06Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1582This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15822016-05-24T01:36:58ZPressure sensor based on bipolar discharge corona configurationWe present a pressure sensing unit based on a unique corona discharge setup using symmetrical electrode arrangement with simultaneous positive and negative corona generation. The device generates stable corona discharge and enables reliable air pressure measurement in the range of 80-105 kPa, tested with five prototypes. The current-voltage characteristics of bipolar discharge system is analyzed in general form and three governing parameters, namely electrode geometry, electrode distance and discharge current, are studied in relation with absolute pressure. The sensors are driven with constant discharge current as low as 1 μA. The measured sensitivity is in good agreement with theoretical prediction and the sensor stability has been confirmed with 20-h continuous test without sensitivity deterioration. The sensitivity does not depend on the tested temperature range and its variation between devices is small, approximately ±3.0%. The advantage of the proposed system compared with similar corona-based constructions is its stable operation at low current with low power consumption and minimum electrode deterioration, which provides a cost effective and reliable solutionThanh Van Daudauthanhvan@gmail.comThanh Tung Buitungbt@vnu.edu.vnXuan Thien Dinhthien@cfd.ritsumei.ac.jpTibor Terebessytibor.terebessy@clearviewtraffic.com2016-05-24T01:35:06Z2016-12-31T14:15:44Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1579This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15792016-05-24T01:35:06ZBipolar corona discharge based air flow generation with low net chargeIn this paper, we report on a miniaturized device that can generate ion wind flow with very low net charge. Both positive and negative ions are simultaneously generated from two sharp electrodes placed in parallel, connected to a single battery-operated power source. The two-electrode arrangement is symmetrical, where the electrode creating charged ions of one polarity also serves as the reference electrode to establish the electric field required for ion creation by the opposite electrode, and vice versa. The numerical simulation is carried out with programmable open source OpenFOAM, where the measured current-voltage is applied as boundary condition to simulate the electrohydrodynamics flow. The air flow inside the device is verified by eight hotwires embedded alongside the downstream channel. It was confirmed that the jet flow generated in the channel has a linear relationship with the square root of the discharge current and its measured values agree well with simulation. The device is robust, ready-to-use and minimal in cost. These are important features that can contribute to the development of multi-axis fluidic inertial sensors, fluidic amplifiers, gas mixing, coupling and analysis. The proposed configuration is beneficial with space constraints and/or where neutralized discharge process is required, such as inertial fluidic units, circulatory flow heat transfer, electrospun polymer nanofiber to overcome the intrinsic instability of the process, or the formation of low charged aerosol for inhalation and deposition of charge particles.Thanh Van Daudauv@sc.sumitomo-chem.co.jpXuan Thien Dinhthien@cfd.ritsumei.ac.jpTibor Terebessytibor.terebessy@clearviewtraffic.comThanh Tung Buitungbt@vnu.edu.vn2016-05-23T07:43:31Z2016-05-23T07:44:36Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1524This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15242016-05-23T07:43:31ZMột số phương pháp phân tích sự ảnh hưởng khi thay đổi mã nguồn phần mềmBảo trì phần mềm hiện nay được đánh giá là một trong những giai đoạn khó khăn nhất, tốn kém nhất và đòi hỏi kỹ thuật cao trong suốt quá trình phát triển phần mềm. Các sản phẩm phần mềm thường xuyên có những thay đổi như thêm mới yêu cầu, sửa lỗi phần mềm trong khi lập trình viên thường chỉ có mã nguồn, không có hoặc thiếu tài liệu phát triển phần mềm. Mỗi sự thay đổi có thể tác động đến rất nhiều phần khác nhau của chương trình. Phân tích sự ảnh hưởng khi thay đổi phần mềm (Software change impact analysis - CIA) là các kỹ thuật nhằm xác định những tác động này, đóng vai trò quan trọng trong việc hiểu về chương trình, dự đoán những tác động, đánh giá chi phí, lựa chọn các ca kiểm thử để kiểm thử lại cũng như thực hiện chiến lược sửa đổi.
Các kỹ thuật CIA được quan tâm của rất nhiều chuyên gia, từ tiếp cận theo hướng phân tích tĩnh cũng như phân tích động chương trình. Tuy nhiên những kết quả hiện tại chưa đủ mạnh để áp dụng trong thực tiễn khi độ chính xác của các kỹ thuật này còn thấp, tập các thành phần bị ảnh hưởng bởi thay đổi tìm được thường quá lớn. Bên cạnh đó các kỹ thuật CIA cho các ứng dụng phức tạp (khối lượng mã nguồn lớn, chứa nhiều loại ngôn ngữ lập trình, …) chưa thu được kết quả khả quan. Chính vì vậy chúng tôi dự kiến phát triển các kỹ thuật CIA đáp ứng những vấn đề trên với các mục tiêu cụ thể:
• Đề xuất kỹ thuật CIA mới cải tiến độ chính xác của tập IS dựa trên sự kết hợp một số kỹ thuật truyền thống với các kỹ thuật dựa trên lịch sử phiên bản phần mềm
• Nghiên cứu khả năng ứng dụng trong việc lựa chọn ca kiểm thử để kiểm thử lại và lựa chọn kế hoạch sửa đổi phần mềm khi có yêu cầu nâng cấp, dựa trên việc phân hạng các phần tử trong tập IS
• Phát triển các công cụ hỗ trợ các phương pháp đề xuất và thực nghiệm với những phần mềm kích thước lớn, độ phức tạp cao
Một số kết quả dự kiến:
• 01 bài báo đăng trên tạp chí khoa học quốc tế.
• 02 bài báo đăng trên tạp chí khoa học có uy tín ở trong nước.
• 02 bài báo cáo trên hội nghị quốc tế.
• Đề xuất phương pháp mới với độ chính xác cao hơn các phương pháp trước đây
• Xây dựng công cụ hỗ trợ có thể ứng dụng trong thực tế
• Đề xuất định hướng ứng dụng các kết quả của kỹ thuật CIA trong bảo trì, kiểm thử lại phần mềm.Ba Cuong LeNgoc Hung Phamhungpn@vnu.edu.vnDinh Hieu Vohieuvd@vnu.edu.vn2016-05-23T07:42:33Z2016-05-23T07:43:06Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1523This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15232016-05-23T07:42:33ZChống tấn công từ chối dịch vụ tốc độ thấp vào giao thức TCP bằng
các cải tiến cơ chế quản lý hàng đợi tích cực.Tấn công từ chối dịch vụ tốc độ thấp vào giao thức TCP (LDoS) là hình thức tấn công từ chối dịch vụ phân tán (DDoS) mới hiện nay, đã được giới thiệu lần đầu tiên bởi Aleksandar Kuzmanovic và Edward W. Knightly năm 2003. LDoS khai thác điểm yếu của giao thức TCP đó là sử dụng giá trị thời gian chờ phát lại gói tin nhỏ nhất minRTO là hằng số bằng 1 giây. Chống LDoS trở nên khó khăn hơn so với chống DDoS thông thường vì LDoS gửi gói tin với tốc độ trung bình thấp nên nó tránh được sự phát hiện của các bộ giám sát mạng (chủ yếu phát hiện bất thường dựa trên sự bùng nổ gói tin vào mạng). Nghiên cứu đưa ra độ đo mới Congestion Participation Rate (CPR) để phân biệt dòng TCP thông thường và dòng tấn công LDoS, cải tiến thuật toán quản lý hàng đợi RED (Random Early Detection) để chống LDoS. Kết quả mô phỏng bằng phần mềm NS-2 cho thấy chỉ số CPR của dòng TCP thường nhỏ hơn so với chỉ số CPR của dòng tấn công LDoS; trên cơ sở đó, thuật toán loại bỏ gói tin của các dòng có chỉ số CPR cao và cho đi qua gói tin của các dòng có chỉ số CPR thấp.Minh Viet KieuDai Tho Nguyenthond@vnu.edu.vnThanh Thuy Nguyennguyenthanhthuy@vnu.edu.vn2016-05-23T07:41:25Z2016-05-23T07:41:54Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1522This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15222016-05-23T07:41:25ZPhương pháp trích trọn đặc trưng hiệu quả cho dữ liệu có số chiều lớnPhân lớp là một trong những bài toán cơ bản trong khai phá tri thức và dữ liệu. Một thách thức của bài toán phân lớp là số lượng thuộc tính thường rất lớn, việc phân lớp sao cho chính xác và hiệu quả hiện vẫn là một nghiên cứu thú vị cho các nhà khoa học trong lĩnh vực khoa học máy tính. Bài báo đi sâu vào nghiên cứu giải thuật phân lớp random forest (RF). Đây là một giải thuật đã được nhiều nghiên cứu chứng minh là rất hiệu quả trong phân lớp đối với bộ dữ liệu có số lượng thuộc tính lớn. Trên cơ sở đó chúng tôi đề xuất một phương pháp học máy cho giải thuật phân lớp này nhằm tăng hiệu quả phân lớp của thuật toán. Cách tiếp cận này về cơ bản đã làm tăng khả năng phân lớp của giải thuật RF, phương pháp đề xuất còn cho thấy khả năng phân lớp tốt hơn một số phương pháp trích chọn đã được công bố. Như vậy, hướng cải tiến mà chúng tôi đề xuất là có khả thi và thu được kết quả tương đối cao.Van Sang Ha2016-05-23T07:40:26Z2016-05-23T07:41:01Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1521This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15212016-05-23T07:40:26ZTích hợp dữ liệu sử dụng học đa nhân kết hợp với giảm chiều dữ liệu thực hiện phân cụm các bệnh nhân ung thư.Mặc dù các nghiên cứu về ung thư đang diễn ra nhưng các phương pháp điều trị hiện có là rất hạn chế về số lượng và hiệu quả, ngoài ra quyết định điều trị cho các bệnh nhân vẫn là một vấn đề khó khăn. Việc thành lập các phân nhóm giúp trợ giúp ra quyết định chủ yếu vẫn dựa trên các loại dữ liệu riêng biệt. Tuy nhiên, việc phân tích dữ liệu bệnh nhân đa chiều dựa trên nhiều số đo đặc trưng phân tử khác nhau như: biểu thức Gene, DNA Methylation, biểu thức miRNA có thể giúp phát hiện các đặc điểm nội tại của các khối u chính xác hơn. Một phương pháp giúp tích hợp dữ liệu từ nhiều dạng đặc tả khác nhau dựa trên phương pháp học đa nhân đồng thời kết hợp với việc giảm chiều dữ liệu được chúng tôi sử dụng trong báo cáo này nhằm tạo nên một bộ dữ liệu có tính tổng quát cao hơn từ nhiều loại biểu diễn dữ liệu khác nhau. Sau khi tích hợp dữ liệu, chúng tôi tiến hành phân cụm bệnh nhân ung thư dựa trên dữ liệu đã tích hợp và đánh giá kết quả phân cụm thu được. Ngoài ra chúng tôi cũng đưa ra các gợi ý về mặt lựa chọn hàm nhân cho các loại dữ liệu cũng như các tham số để đạt được kết quả phân cụm tốt nhất cho mô hình này.Thanh Trung GiangDang Hung Tran2016-05-23T07:39:18Z2016-05-23T07:40:02Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1520This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15202016-05-23T07:39:18ZNâng cao hiệu năng xử lý truy vấn với mô hình dữ liệu trong bộ nhớCác hệ quản trị cơ sở dữ liệu (CSDL) truyền thống chủ yếu được xây dựng dựa trên việc khai thác các máy tính đơn nhân CPU và thiết bị lưu trữ kiểu từ tính. Các mô hình này chưa khai thác được hết những thế mạnh công nghệ của các chip đa nhân hay những hệ thống máy tính cụm và dung lượng càng ngày càng lớn của bộ nhớ chính. Để có thể nâng cao được hiệu năng xử lý truy vấn, nhiều mô hình xử lý mới đã được đưa ra như H-Store với tư tưởng dựa trên mô hình dữ liệu trong bộ nhớ chính; Map-Reduce kết hợp Hadoop FileSystem để xử lý phân tán, … Từ thực trạng đó, luận án này hướng đến mục tiêu nghiên cứu, cải thiện mô hình xử lý truy vấn với loại dữ liệu không gian chuyên biệt theo hai hướng kết hợp: khai thác tối đa không gian bộ nhớ chính khả dụng và phân rã các truy vấn để có thể tiến hành song song trên nhiều lõi/chip khác nhau. Mô hình thử nghiệm sẽ được tiến hành dựa trên những bài toán kinh điển như tìm lộ trình tối ưu giữa hai vị trí địa lý khác nhau, các truy vấn trên mạng xã hội, mạng IoT, …Phuong Hanh DuHai Chau Nguyenchaunh@vnu.edu.vnKim Thoa Nguyen2016-05-23T07:38:11Z2016-05-23T07:38:57Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1525This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15252016-05-23T07:38:11ZSieve-based coreference resolution enhances semi-supervised learning model for chemical-induced disease relations extractionThe BioCreative V chemical-disease relation (CDR) track was proposed to accelerate progress of text mining in facilitating integrative understanding of chemical substances, diseases and their relations. In this article, we describe an extension of the UET-CAM system for mining chemical- disease relations from text data, of which performance was ranked 4th among 18 participating corresponding systems by the BioCreative CDR track committee. In Disease Named Entity Recognition and Normalization (DNER) phase, our system employs joint learning with a perceptron-based named entity recognizer (NER) and a back-off model with Semantic Supervised Indexing (SSI) and Skip-gram for named entity normalization (NEN). Crucially, for solving the chemical-induced disease (CID) sub-task, we propose a pipeline that includes a coreference resolution module and a SVM intra-sentence relations extraction model. The former module utilizes a multi-pass sieve to identify inter-sentence references for entities while the latter is trained on both the CDR data and our silverCID corpus with a rich feature set. SilverCID is the silver standard corpus contains more than 50 thousands sentences which are automatically built based on the CTD database in order to provide evidence for the CID relation extraction. We critically evaluated our method on the CDR test set in order to clarify the contribution of our system components. Results show an F1 of 82.44 for the DNER task, and a best performance of F1 58.90 on the CID task. The comparisons also demonstrate the significant contribution of the multi-pass sieve coreference resolution method and the silverCID corpus.Hoang Quynh LeMai Vu Tranvutm@vnu.edu.vnThanh Hai DangQuang Thuy Hathuyhq@vnu.edu.vnCollier Nigel2016-05-23T07:37:04Z2016-05-23T07:37:50Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1526This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15262016-05-23T07:37:04ZFingerprint Matching on GPU for a Large Scale
Identification SystemFingerprints are most used biometrics features for identification. Although state-of-the-art algorithms are very accurate, but the need for processing speed for databases with millions fingerprints are very demanding. GPU devices are used widely in parallel computing tasks for their efficiency and low-cost. Most approaches make use of GPU for the filtering process in a multi-stage matching system. In this paper, we present a complete fingerprint matching algorithm on GPU. Our approach uses minutia cylinder-code (MCC) representation with a global consolidation stage and a careful design to make it suitable for the architecture of GPU. The result tested with GTX- 680 device shows that the proposed algorithm can perform 1.8 millions matches per second, making it applicable for real time identification systems with databases of millions fingerprints.Hong Hai Le2016-05-23T05:59:03Z2016-05-23T05:59:46Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1527This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15272016-05-23T05:59:03ZLearning to Filter User Explicit Intents in Online Vietnamese Social Media TextsToday, Internet users are much more willing to express them- selves on online social media channels. They commonly share their daily activities, their thoughts or feelings, and even their intention (e.g., buy a camera, rent an apartment, borrow a loan, etc.) about what they plan to do on blogs, forums, and especially online social networks. Understand- ing intents of online users, therefore, has become a crucial need for many enterprises operating in different business areas like production, banking, retail, e–commerce, and online advertising. In this paper, we will present a machine learning approach to analyze users’ posts and comments on online social media to filter posts or comments containing user plans or intents. Fully understanding user intent in social media texts is a compli- cated process including three major stages: user intent filtering, intent domain identification, and intent parsing and extraction. In the scope of this study, we will propose a solution to the first one, that is, building a binary classification model to determine whether a post or comment carries an intent or not. We carefully conducted an empirical evaluation for our model on a medium–sized collection of posts in Vietnamese and achieved promising results with an average accuracy of more than 90%.
Keywords: Intention mining, user intent identification, social media text understanding, content filtering, text classificationThai Le LuongThi Hanh TrangQuoc Tuan TruongThi Minh Ngoc TruongThi Thu PhiXuan Hieu Phanhieupx@vnu.edu.vn2016-05-23T05:25:14Z2016-05-24T03:00:51Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1528This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15282016-05-23T05:25:14ZPhương pháp kiểm chứng các tính chất an ninh của phần mềmTrong giai đoạn kỹ thuật công nghệ phát triển như hiện nay, an ninh là yêu cầu quan trọng đối với hệ thống chăm sóc sức khỏe vì nhu cầu cần bảo vệ các thông tin riêng tư của bệnh nhân. Việc tích hợp các chính sách an ninh vào hệ thống phần mềm này là rất cần thiết để giảm thiểu các vi phạm an ninh. Kiểm soát truy cập dựa trên vai trò là phương pháp hiệu quả để thực hiện các tính chất an ninh cơ bản của một phần mềm an toàn. Nghiên cứu trình bày một phương pháp để đặc tả các yêu cầu an ninh trong hệ thống khám chữa bệnh. Bên cạnh việc đề xuất một phương pháp chứng minh sự đáp ứng của các yêu cầu an ninh với một hệ thống phần mềm này, một công cụ kiểm chứng cũng được giới thiệu.Thanh Nhan LuongNinh Thuan Truongthuantn@vnu.edu.vn2016-05-23T05:24:00Z2016-05-23T05:24:43Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1529This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15292016-05-23T05:24:00ZIdentifying User Intents in Vietnamese Spoken Language Commands and Its Application in Smart Mobile Voice InteractionThis paper presents a lightweight machine learning model and a fast conjunction matching method to the problem of identifying user intents behind their spoken text commands. These model and method were integrated into a mobile virtual assistant for Vietnamese (VAV) to understand what mobile users mean to carry out on their smartphones via their commands. User intent, in the scope of our work, is an action associated with a particular mobile application. Given an input spoken command, its application will be identified by an accurate classifier while the action will be determined by a flexible conjunction matching algorithm. Our classifier and conjunction matcher are very compact in order that we can store and execute them right on mobile devices. To evaluate the classifier and the matcher, we annotated a medium–sized data set, conducting various experiments with different settings, and achieving impressive accuracy for both the application and action identification.Thi Lan NgoBao Son Phamsonpb@vnu.edu.vnXuan Hieu Phanhieupx@vnu.edu.vn2016-05-23T05:22:07Z2016-05-23T05:22:44Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1530This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15302016-05-23T05:22:07ZA type system for calculating the maximum log memory used by transactional programsWe developed a type system for estimating an upper bound of memory that multi-threaded and nested transactional programs may require for their transaction logs. In our previous works, we only esti- mated the maximum number of logs that can coexist by static type and effect systems. This work extends our previous language that allows ones to specify also the size of logs in a transaction, and then develop a type system that can infer the memory bound required by the transaction logs.Ngoc Khai NguyenAnh Hoang Truonghoangta@vnu.edu.vnVan Hung Dang2016-05-23T05:20:43Z2016-05-23T05:21:36Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1531This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15312016-05-23T05:20:43ZMô hình hóa và kiểm chứng các hệ thống thứ lỗi và cân bằng tảiTrong thiết kế nói chung, tùy thuộc vào mức độ quan trọng, tính chất sống còn của hệ thống đòi hỏi người thiết kế phải đảm bảo tính liên tục trong hoạt động của hệ thống. Ví dụ như hệ thống điều khiển bay, hệ thống cơ sở dữ liệu của các ngân hàng,…Hệ thống thứ lỗi (fault tolerance systems) là khả năng đảm bảo cho hệ thống tiếp tục thực hiện các chức năng của mình khi một phần của hệ thống gặp sự cố. Nói cách khác, hệ thống có thể cung cấp các dịch vụ trong khi vẫn tồn tại lỗi. Nghiên cứu trình bày một phương pháp để mô hình hóa và kiểm chứng tính chất của hệ thống chịu lỗi và cân bằng tải. Bên cạnh đó việc xây dựng và thử nghiệm công cụ kiểm chứng tính chất của hệ thống chịu lỗi và cân bằng tải cũng sẽ được giới thiệu.Hanh Phuc NguyenNinh Thuan Truongthuantn@vnu.edu.vn2016-05-23T05:15:25Z2016-05-29T10:43:39Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1584This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15842016-05-23T05:15:25ZDesign of a C-Band Low-Noise Block Front-end for Satellite ReceiversThis paper describes the study, design and fabrication of a C-band low-noise block front-end for satellite receivers. The front-end consists of a low-noise amplifier, two band pass filters in C-band and L-band, a down-converter and an intermediate frequency amplifier. To reduce noise figure and increase bandwidth, the low-noise amplifier was designed using T-type of matching network with negative feedback. The down-converter used a voltage controlled oscillator with phase locked loop to reduce the phase noise. The front-end converts input signals from C-band (3.4 GHz - 4.2 GHz) to the L-band (950 MHz - 1750 MHz). The low-noise block has successfully been designed and fabricated with parameters: Overall gain is greater than 60 dB; the noise figure is less than 2dB; phase noise of local oscillator obtains -107.57dBc /Hz at 50KHz.Van Hoi Trantranvanhoi@vov.org.vnXuan Truong Nguyennguyenxuantruong@vov.org.vnThi Lanh Ngongothilanh@vov.org.vnGia Duong Bachduongbg@vnu.edu.vn2016-05-23T03:34:19Z2016-05-23T03:34:55Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1532This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15322016-05-23T03:34:19ZAutomatic Detection of Problematic Rules in Vietnamese TreebankViet Treebank is an annotated corpus newly published in 2009. In this paper, we applied automated methods to detect errors in Viet Treebank based on the concept of equivalence classes proposed by Dickinson. On this basis, we propose an improved method of error detection by transforming the syntax tree based on vertical markovization. Our experimental results on Viet Treebank showed that the scope of error detection extended more than 2 times and improved the precision more than 18.07% in comparison with the base line methods.Hong Quan NguyenPhuong Thai Nguyenthainp@vnu.edu.vnThanh Quyen DangVan Hiep Nguyen2016-05-23T03:33:09Z2016-05-23T03:34:00Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1533This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15332016-05-23T03:33:09ZMột phương pháp thủy vân thuận nghịch mới dựa trên dịch chuyển histogramBài báo đề xuất một phương pháp thủy vân thuận nghịch mới dựa trên dịch chuyển histogram (DCH). Trong khi hầu hết các phương pháp thủy vân dựa trên DCH không có khả năng đóng gói mọi thông tin cần thiết về ảnh gốc vào ảnh thủy vân, nên ở giai đoạn khôi phục chúng phải sử dụng một số thông tin phụ về ảnh gốc, thì phương pháp đề xuất đã khắc phục được nhược điểm trên và không cần sử dụng bất kỳ thông tin phụ nào về ảnh gốc để khôi phục dấu thủy vân cũng như ảnh gốc. Các phương pháp thủy vân như vậy gọi là có tính đóng gói hoặc độc lập thông tin phụ. Giải pháp đóng gói được sử dụng ở đây là kết hợp kỹ thuật chèn bít thấp và dịch chuyển histogram. Ảnh gốc được chia thành hai miền: miền đầu gồm một số ít điểm ảnh được sử dụng để nhúng thông tin phụ bằng kỹ thuật chèn bít thấp, miền thứ hai gồm phần còn lại của ảnh, dùng để nhúng dấu thủy vân theo phương pháp DCH. So sánh với các phương pháp độc lập thông tin phụ khác, phương pháp đề xuất có khả năng nhúng cao hơn và độ phức tạp tính toán thấp hơn. Ưu điểm của giải pháp đóng gói đề xuất là đơn giản, hiệu quả và có thể dễ dàng áp dụng đối với hầu hết các phương pháp thủy vân DCH khác.Kim Sao NguyenQuang Hoa LeVan At Pham2016-05-23T03:31:56Z2016-05-23T03:32:45Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1534This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15342016-05-23T03:31:56ZImproving Maximum Entropy Part-of-Speech Tagger with Transformation Based Learning ModelAs well know, part-of-Speech (POS) tagging is basic and central problem of natural language processing branch. Development of a POS tagger will influence several pipelined modules of natural language understanding system including information extraction and retrieval; machine translation; partial parsing and word sense disambiguation. In recent years, there has been a growing interest in data-driven machine learning disambiguation methods for POS tagging with results be very close state-of-art of this problem. Improvement performance of these methods has been posed challenges for researchers. In this paper, we use one of the best machine learning method (Maximum Entropy Model - MEM) to do automatic annotation of part-of-speech in basedline then improve accuracy by using Transformation Based Learning (TBL). Our approach based on an incremental knowledge acquisition method where rules are stored in an exception structure and new rules are only selected to correct the errors are positive on courpus. Experimental results on English Peen Treebank show that our method greatly improve accuracy than the naive baseline model with state-of-the-art accuracy(97.14%). Special, we also do experiments on Vietnamese Viet TreeBank corpus and experimental results show that the proposed Vietnamese POS tagging system outperforms the other state-of-the-art Vietnamese taggers with 93.50% overall accuracy.Ngoc Khuong NguyenDuc Hong PhamAnh Cuong Lecuongla@vnu.edu.vnHong Thai Phampht@vnu.edu.vn2016-05-23T03:30:55Z2016-05-24T03:00:19Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1535This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15352016-05-23T03:30:55ZNghiên cứu về gán nhãn vai nghĩa cho tiếng ViệtGán nhãn vai nghĩa (Semantic Role Labeling - SRL) là bài toán xác định vai nghĩa cho các thành phần trong câu, làm rõ cấu trúc, mối quan hệ giữa vị từ và các tham đối cấu thành câu. Về bản chất, gán nhãn vai nghĩa chỉ là một bài toán trung chuyển, chứ không thật sự là nền tảng của một ứng dụng xử lý ngôn ngữ tự nhiên cụ thể nào. Tuy nhiên, đây lại là một bước cần thiết không thể bỏ qua trong các ứng dụng liên quan đến ngôn ngữ tự nhiên. Việc xác định đúng vai nghĩa của các thành phần trong câu là một vấn đề trung tâm của mọi hệ xử lý ngôn ngữ tự nhiên. Gán nhãn vai nghĩa thực chất là một dạng phân tích ngữ nghĩa nông, xác định và gán nhãn vai nghĩa cho các thành phần trong câu đối với một vị tố cụ thể, thông thường là động từ. Trong các nghiên cứu của mình, chúng tôi tiến hành định nghĩa một số vai nghĩa thông dụng, xây dựng kho ngữ liệu tiếng Việt có gán nhãn vai nghĩa. Bước đầu áp dụng phương pháp phân tích cú pháp đầy đủ để xây dựng công cụ gán nhãn vai nghĩa tự động cho tiếng Việt. Các thử nghiệm với tiếng Việt cho kết quả tương đối khả quan và đáng tin cậy.Quang Huy NguyenVan Vinh NguyenPhu Binh Nguyen2016-05-23T03:29:23Z2016-05-23T03:29:53Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1536This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15362016-05-23T03:29:23ZLogic-used Methods Solving Uncertainty and Inconsistency in
Knowledge Intergration and ApplicationsWorking out representation methods for inconsistent knowledge is one of the most important tasks in the Knowledge Integration field. It is the representation structures, which decide the way how a knowledge system collects and processes the conflict knowledge, and thus it influences directly the ability and effectiveness of the system. One effective way to present inconsistent knowledge is using paraconsistent logics. In this paper, I present a case study of several paraconsistent logics that allow representing inconsistency and processing it. In each of these logics I will present the semantic, the proof theory and the applicability. With the aim to develop the representation of inconsistent information in a distributed system, I propose a model of paraconsistent logic for distributed system.Thi Hong Khanh NguyenQuang Thuy Hathuyhq@vnu.edu.vnAnh Linh Nguyen2016-05-23T03:27:06Z2016-05-23T03:28:01Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1537This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15372016-05-23T03:27:06ZBuilding ancestral recombination graphs for whole genomesAncestral Recombination Graph (ARG) plays an important role in human population genetics. Nevertheless, most of current ARG inference algorithms are only applicable to small data sets due to their computational burden. Margarita by Minichiello and Durbin [1] can handle larger data sets; however, it is still not feasible at genome scale. We hereby propose a heuristic algorithm, called ARG4WG, to construct plausible ARGs from thousands of whole chromosome samples, in which the so-called longest shared end, i.e. the longest match between left or right ends of sequences, is used for recombination in the building process. This strategy not only allows ARG4WG to significantly reduce the computational cost, by hundreds to thousands times faster than Margarita but also leads to ARGs with fewer number of recombination events. The ARGs resulted from our algorithm also perform reasonably well in association study with 5560 haplotypes across whole chromosome 11 of Gambia dataset. These results indicate that ARG4WG is a good candidate for genome-wide association study from large data sets.Thi Phuong Thao NguyenSy Vinh Levinhls@vnu.edu.vnBich Hai HoSi Quang Le2016-05-23T03:25:39Z2016-05-23T03:26:45Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1538This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15382016-05-23T03:25:39ZPhân loại câu hỏi sử dụng nhiều loại đặc trưngPhân loại câu hỏi là một thành phần quan trọng trong các hệ thống hỏi đáp tự động. Nhiệm vụ chính của phân loại câu hỏi là dự báo kiểu thực thể của câu trả lời của các câu hỏi viết bằng ngôn ngữ tự nhiên. Phân loại câu hỏi có thể được thực hiện bằng các tiếp cận khác nhau như: tiếp cận dựa trên luật, tiếp cận dựa trên học máy. Các đặc trưng khác nhau về từ vựng, cú pháp và ngữ nghĩa có thể được trích xuất tự động từ các câu hỏi để phục vụ việc phân loại. Trong nghiên cứu này chúng tôi kết hợp các đặc trưng về từ vựng, cú pháp, ngữ nghĩa trong phân loại câu hỏi. Chúng tôi đề xuất sử dụng mẫu câu hỏi (Question pattern) như là một đặc trưng mới để kết hợp với các đặc trưng khác trong phân loại câu hỏi. Chúng tôi cũng đề xuất sử dụng các tập đặc trưng khác nhau cho mỗi nhóm câu hỏi với các từ để hỏi khác nhau. Chúng tôi nhận thấy rằng khi sử dụng mẫu câu hỏi như là một đặc trưng và kết hợp với các đặc trưng từ vựng, cú pháp, ngữ nghĩa khác có thể cải thiện đáng kể độ chính xác của phân loại câu hỏi. Chúng tôi đã kiểm tra những đề xuất của mình bằng cách sử dụng bộ phân loại Support Vector Machine trên bộ dữ liệu TREC và đã đạt được độ chính xác phân loại câu hỏi cao hơn so với những nghiên cứu trước đó trên cùng nguyên tắc phân loại và tập dữ liệu.Van Tu NguyenAnh Cuong Lecuongla@vnu.edu.vnHa Nam Nguyennamnh@vnu.edu.vn2016-05-23T03:24:14Z2016-05-23T03:25:02Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1539This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15392016-05-23T03:24:14ZPhát hiện và theo dõi các sự kiện truyền thông xã hội trực tuyến cho tiếng ViệtNgày nay, mạng internet cung cấp cho người dùng một lượng lớn thông tin và tri thức. Đặc biệt, trong những năm gần đây, số lượng người dùng mạng xã hội (social network) ngày càng tăng. Bởi sự tiện lợi, dễ dàng của nó mà những thông tin, sự kiện của thế giới thực thường được đăng tải trên các mạng xã hội ngay khi nó xảy ra. Trong khi đó các trang tin tức khác trên mạng thường đăng tải các thông tin này chậm hơn. Thậm chí, nhiều thông tin được đăng tải trên các trang mạng xã hội nhưng không được đăng tải qua các trang tin tức khác. Tin tức, thông tin, sự kiện sẽ có giá trị cao khi nó được truyền tải đến người dùng nhanh và chính xác. Vậy làm thế nào để tự động phát hiện, tập hợp nhanh các sự kiện đó và trả lời được các câu hỏi “sự kiện gì, xảy ra ở đâu? thời gian nào? diễn biến của sự kiện đó như thế nào?...” cho người dùng?
Trong nghiên cứu này, chúng tôi muốn xây dựng một hệ thống phát hiện và theo dõi các sự kiện thông qua việc sử dụng dữ liệu là các tin tức (news) trên các trang mạng, các bình luận (comment), các bài (post) trên mạng xã hội Facebook và ngôn ngữ của các dữ liệu này là tiếng Việt.Van Toi NguyenBao Son Phamsonpb@vnu.edu.vnXuan Hieu Phanhieupx@vnu.edu.vn2016-05-23T03:20:53Z2016-05-23T03:23:41Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1541This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15412016-05-23T03:20:53ZOn Model-Checking Probabilistic Timed Automata against Probabilistic Duration PropertiesIn this paper, we consider a subclass of Probabilistic Duration Cal- culus formula called Simple Probabilistic Duration Calculus (SPDC) as a language for specifying dependability requirements for real-time systems, and address the two problems: to decide if a probabilistic timed automaton satisfies a SPDC formula, and to decide if there is a strategy to choose an execution of a given automaton that satisfies a SPDC formula. We prove that the both problems are decidable for a class of SPDC called probabilistic linear duration invariants, and provide a model checking algorithm for solving these problems.Dinh Chinh PhamZhang MiaomiaoVan Hung Dang2016-05-23T03:18:31Z2016-05-23T03:19:37Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1542This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15422016-05-23T03:18:31ZThiết kế ngữ nghĩa hình thang cho hệ phân lớp dựa trên luật mờHệ phân lớp dựa trên luật mờ được nghiên cứu rộng rãi do người dùng cuối có thể sử dụng những tri thức dạng luật được trích rút từ dữ liệu có tính dễ hiểu, dễ sử dụng đối với con người như là những tri thức của họ. Giải bài toán phân lớp dựa trên luật mờ là xây dựng bài toán trích rút tự động hệ dựa trên luật mờ từ dữ liệu sao cho hệ luật thu được phải dễ hiểu, tức là số luật và số điều kiện tạo nên luật phải đủ nhỏ, các giá trị ngôn ngữ của các từ ngôn ngữ xuất hiện trong hệ luật phải phản ánh được đúng ngữ nghĩa của bản thân chúng nhưng vẫn đáp ứng được yêu cầu đặt ra của bài toán.
Đại số gia tử (ĐSGT) là một cách tiếp cận mới cho việc xử lý miền giá trị của biến ngôn ngữ, khai thác tính chất sánh được của các giá trị ngôn ngữ, là cơ sở xác định ngữ nghĩa định lượng từ ngữ nghĩa định tính, đã cho phép tạo ra các ràng buộc về ngữ nghĩa và đã được ứng dụng hiệu quả trong quá trình tìm kiếm, thiết kế tập giá trị ngôn ngữ cùng với ngữ nghĩa dựa trên tập mờ của chúng cho bài toán xây dựng tự động cơ sở luật cho hệ phân lớp dựa trên luật mờ. Tuy nhiên, với tiếp cận ĐSGT hiện tại, ngữ nghĩa lõi và ngữ nghĩa dựa trên tập mờ hình thang của các từ ngôn ngữ chưa được mô hình hóa. Nghiên cứu này đề xuất mở rộng lý thuyết ĐSGT biểu diễn được ngữ nghĩa của các từ ngôn ngữ phụ thuộc ngữ cảnh và đề xuất thay đổi phương pháp lượng hóa ĐSGT để mô hình hóa ngữ nghĩa định tính của các từ ngôn ngữ phù hợp với ngữ cảnh mới nhằm cung cấp một cơ chế hình thức cho việc sinh lõi ngữ nghĩa và ngữ nghĩa tính toán dựa trên tập mờ hình thang của khung nhận thức ngôn ngữ. Nghiên cứu này cũng chứng tỏ khả năng ứng dụng hiệu quả của ĐSGT mở rộng trong thiết kế tự động hệ phân lớp dựa trên luật mờ.Dinh Phong Pham2016-05-23T03:13:39Z2016-05-23T03:14:15Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1543This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15432016-05-23T03:13:39ZA Least Square based Model for Rating Aspects and Identifying Important Aspects on Review Text DataIn recent years, opinion mining and sentiment analysis has been one of the attracting topics of knowledge mining and natural language processing. The problem of rating aspects from textual reviews is an important task in this field. In this paper we propose a new method for rating product aspects as well as for identifying important aspects in general. Our proposed model is based on the least square method and the QR decomposition technique. In our experiment, we use a dataset of 594810 reviews of 3775 hotels collected from the very famous website in tourism tripadvisor.com with five common aspects including cleanliness, location, service, room and value. Experimental result shows that our proposed method outperforms some well known studies for the same problem.Duc Hong PhamAnh Cuong Lecuongla@vnu.edu.vn2016-05-23T03:12:20Z2016-05-23T03:12:52Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1544This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15442016-05-23T03:12:20ZThe vector machine learning methods on sign language recognition problemHuman gesture recognition is a rather new field and many challenges, especial when motion capture devices become more popular. Sign language recognition is a concrete example of gesture recognition. Various studies have shown that the vector machine methods with Gaussian kernels are among the most prominent models for an accurate gesture classification. In this study, we present the application of vector machine learning methods to sign language recognition problem. We demonstrate that the vector machines (VMs) could also achieve the state-of-the-art predictive performance. The experimental results on the Auslan data set show the feasibility and effectiveness of these methods.Quoc Thang PhamDuc Dung NguyenThanh Thuy Nguyennguyenthanhthuy@vnu.edu.vn2016-05-23T03:11:11Z2016-05-23T03:12:00Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1545This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15452016-05-23T03:11:11ZHidden Topic Models for Multi-Label Review Classification: An Experimental StudyIn recent years, Multi-Label Classification (MLC) has become an important task in the field of Supervised Learning. The MLC tasks are omnipresent in real-world problems in which an instance could belong to different classes simultaneously. In this paper, we presented a method for MLC using the hidden topic method to enrich the data features and using mutual information for feature selection. Our experiments on classifying user reviews about one thousand Vietnamese hotels showed the efficacy of the proposed approach.Thi Ngan PhamThi Thom PhanPhuoc Thao NguyenQuang Thuy Hathuyhq@vnu.edu.vn2016-05-23T03:05:07Z2016-05-23T03:06:06Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1546This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15462016-05-23T03:05:07ZResearch and development of methods for Data Stream Mining based on Meta Heuristic, Statistics and Nonparametric LearningDevelop adaptive learning algorithms for Evolving Data Streams is one of the major challenges that we face today. In this research, we propose improved methods aim at answering three main research questions includes (1) What to remember or forget?,(2) When to do the model upgrade? And (3) How to do the model upgrade? These proposed methods are based on Meta Heuristic, Statistic and Nonparametric Learning.Thi Thuong PhamXuan Hoai NguyenTri Thanh Nguyenntthanh@vnu.edu.vn2016-05-23T03:04:06Z2016-05-23T03:04:47Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1547This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15472016-05-23T03:04:06ZMô hình hóa nồng độ bụi sử dụng ảnh vệ tinhViệc sử dụng dữ liệu ảnh sol khí trong giám sát ô nhiễm bụi là một hướng tiếp cận mới và hứa hẹn [1, 3, 5 - 8]. Các ảnh sol khí có thể được tích hợp với dữ liệu quan trắc bụi trong các mô hình ước tính mức độ ô nhiễm nhằm tăng chất lượng tính toán và dự đoán của các mô hình này.
Tại Việt Nam, việc kiểm soát và tính toán lượng bụi và chất lượng không khí từ các tham số đo đạc trên các vùng thí điểm cũng đã được đề cập đến trong nhiều nghiên cứu. Tuy nhiên, việc sử dụng và khai thác các thông tin từ vệ tinh cho bài toán mô hình hoá hoặc ước lượng mức độ ô nhiễm không khí chưa được quan tâm và nghiên cứu rộng rãi tại Việt Nam. Đề tài “Mô hình hóa nồng độ bụi sử dụng ảnh vệ tinh” được nghiên cứu nhằm kế thừa và áp dụng phương pháp sử dụng ảnh vệ tinh cho bài toán Ô nhiễm không khí còn rất hạn chế ở Việt Nam. Đề tài tập trung vào giải quyết các nội dung chính như sau:
➢ Nội dung 1: Các kỹ thuật nâng cao chất lượng sản phẩm sol khí: Các phương pháp, kỹ thuật như Merging (SAA, MLE, WPC), Nội suy IO, Kriging, Phương pháp biến đổ 3D-Var, 4D-Var, bộ lọc Kalman được sử dụng nhằm nâng cao chất lượng sản phẩm sol khí.
➢ Nội dung 2: Xây dựng mô hình ước tính nồng độ Ô nhiễm bụi từ ảnh vệ tinh: Các mô hình ước tính như hồi quy, SVM, Neural Network… được thực nghiệm và đánh giá để tìm ra mô hình ước tính tốt nhất cho dữ liệu trên vùng nghiên cứu.
➢ Nội dung 3: Phân tích và đánh giá ảnh hưởng của Ô nhiễm bụi: Bản đồ nồng độ bụi PM được ước tính từ mô hình được sử dụng cho các bài toán đánh giá ảnh hưởng của Ô nhiễm không khí đế các lĩnh vực khác như sức khỏe cộng đồng [2, 4, 9] (Tỉ lệ tử vong, số lượng bệnh nhân tim mạch, ưng thư…), ảnh hưởng đến nông nghiệp, biến đối khí hậu.Van Ha PhamThi Nhat Thanh Nguyenthanhntn@vnu.edu.vn2016-05-23T03:02:15Z2016-05-23T03:03:14Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1548This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15482016-05-23T03:02:15ZBáo cáo tóm tắt đề tài nghiên cứuTrong một vài thập kỉ trở lại đây, số lượng các thiết bị di động không dây ngày càng trở nên phổ biến. Đi kèm với nó là các đỏi hỏi và nhu cầu sử dụng về các dịch vụ chất lượng cao như truyền thông đa phương tiện, VoIP, VIDEO ngày càng tăng lên Nhu cầu cấp phát dải tần số cho các dịch vụ mạng không dây tăng lên một cách đáng kể dẫn đến cạn kiệt nguồn tài nguyên tần số. Tuy nhiên, trong quá trình đo đạc về mức độ sử dụng tối ưu tần số đã chỉ ra rằng phần lớn các dải tần cấp phát đang bị sử dụng một cách kém hiệu quả, mà nguyên nhân bao gồm việc cách cấp phát, quản lý và khai thác kém hiệu quả . Để tận dụng một cách hiệu quả các dải tần số, một phương pháp sử dụng và quản lý các dải tần số mới được được đề xuất bởi J Mitola với tên gọi mạng vô tuyến nhận thức - Cognitive radio networks (CRNs). Giải pháp này được xem như là một bước tiên phong cho các thế hệ tiếp theo của mạng không dây. Tuy nhiên, CRNs cũng đối mặt với những thách thức. Việc đánh giá, lựa chọn và quản lý phổ tần như thế nào để phù hợp cho nhu cầu truyền hiện tại của các đối tượng trong hệ thống mạng là một trong những thách thức không nhỏ đối với CRNs. Mặt khác, với tính chất truyền thông quảng bá tự nhiên của các mạng không dây nói chung, bất kỳ người nhận nào trong phạm vi của một truyền dẫn không dây đều có khả năng nghe được thông tin truyền đi. Do đó, bảo mật thông tin là mối quan tâm then chốt trong các mạng không dây. Do có độ phức tạp và độ trễ thấp, cũng như tính khả thi ở lớp vật lý và khả năng cùng tồn tại với các cơ chế bảo mật mã hóa hiện có mà nó có thể nâng cao mức độ tổng thể về an toàn thông tin. Vì vậy, bảo mật ở lớp vật lý đã và đang thu hút được sự quan tâm nghiên cứu của các học giả trên khắp thế giới trong thời gian gần đây. Trong phạm vi mô hình mạng CRNs khi có nhiều người dùng đồng thời trong cùng băng tần thì mức công suất của mỗi người dùng cần phải được điều khiển sao cho có thể giảm nhẹ nhiễu không mong muốn, đồng thời cũng phải đáp ứng được nhu cầu bảo mật thông tin, bảo vệ chống lại sự xâm nhập hoặc rò rỉ thông tin. Vì vậy, khả năng đảm bảo bảo mật thông tin của mạng CRNs như thế nào là vấn đề được nhiều người quan tâm.
Dựa trên những hiện trạng ở trên, nghiê cứu sinh đã lựa chọn đề tài “Đánh giá hiệu năng bảo mật tại tầng vật lý trong mạng không dây” nhằm nghiên cứu, đánh giá các vấn đề liên quan đến hiệu suất hoạt động và khả năng bảo mật thông tin của các mô hình mạng nêu trên, góp phần vào giải quyết các thách thức và khó khăn trong việc hiện thực hóa hệ thống mạng vô tuyến nhận thức vào thực tiễn, làm cho công nghệ mạng không dây linh hoạt, thích nghi, đạt hiệu quả cao và an toàn trong liên lạc không dây.Xuan Truong Quach2016-05-23T03:01:17Z2016-05-23T03:01:55Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1549This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15492016-05-23T03:01:17ZImproving English-Vietnamese Statistical Machine Translation Using Preprocessing Dependency SyntacticIn this paper, we would like to present a new reordering approach based on a dependency parser in phrase based statistical machine translation (SMT) for English to Vietnamese. The proposed method can efficiently incorporate linguistic knowledge into SMT systems. We inspired from [1] using preprocessing reordering approaches. Dependency parser and transformation rules are used to reorder the source sentence and applied for systems translating English to Vietnamese. The experiment results showed that the proposed approach achieved improvements in BLEU scores over MOSES which is the state-of-the art phrase based SMT system.Hong Viet TranVan Vinh NguyenLe Minh Nguyen2016-05-23T03:00:03Z2016-05-23T03:01:00Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1550This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15502016-05-23T03:00:03ZExploring a Probabilistic Earley Parser for Event Composition in Biomedical TextsWe describe a high precision system for extracting events of biomedical significance that was developed during the BioNLP shared task 2013 and tested on the Cancer Genetics data set. Our system explored a multi-stage approach including trigger detection, edge detection and event composition. After trigger edge detection is finished we are left with a semantic graph from which we must select the optimal subset that is consistent with the semantic frames for each event type. The system achieved an F-score on the development data of 73.67 but was ranked 5th out of six with an F-score of 29.94 on the test data. How-ever, precision was the second highest ranked on the task at 62.73. Analysis suggests the need to continue to improve our system for complex events particularly taking into account cross-domain differences in argument distributions.Mai Vu Tranvutm@vnu.edu.vnHoang Quynh LeVan Thuy PhiThanh Binh PhamCollier Nigel2016-05-23T02:58:36Z2016-05-23T02:59:08Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1551This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15512016-05-23T02:58:36ZPhân tích và phát hiện lỗ hổng bảo mật trong firmware của các thiết bị mạngCông nghệ ngày càng phát triển mãnh mẽ, đi sâu vào mọi khía cạnh của cuộc sống, do đó vấn đề an ninh an toàn trở thành một trong những vấn đề được quan tâm nhất trong thế giới ngày nay. Nguy cơ về mất an ninh thông tin không chỉ dừng lại mức ứng dụng phần mềm mà đặt ra cả ở mức phần cứng thiết bị và ngày nay một lĩnh vực đang dấy lên nhiều lo ngại là nguy cơ từ các hệ thống nhúng tích hợp, firmware của các thiết bị, đặc biệt các thiết bị đóng vai trò trung tâm trong kết nối, truyền dẫn thông tin như các thiết bị mạng. Các nghiên cứu từ trước tập trung cho các ứng dụng mức cao trên kiến trúc i386, hệ điều hành Windows, các phương pháp và công cụ hỗ trợ cho việc phân tích firmware còn rất hạn chế và gặp nhiều khó khăn do tiếp cận mức thấp, kiến trúc đa dạng, thiếu tài liệu đặc tả đầy đủ. Nghiên cứu của chúng tôi tập trung vào việc tìm hiểu kiến trúc của các thiết bị mạng, từ đó tìm cách trích xuất firmware từ các thiết bị này, sau đó phân tích nhằm phát hiện có hay không các lỗ hổng bảo mật hay malware cài cắm trong firmware. Việc phân tích và phát hiện dựa trên 2 phương pháp tĩnh và động. Các firmware được tiến hành phân tách, thu thập lấy phần thực thi chính của firmware thường là các Embeded Web trên nền Linux 2.6, phần lõi này được tiến hành phân tích tĩnh tìm ra backdoor hoặc chạy trong môi trường mô phỏng để quét phát hiện lỗ hổng bảo mật.Nghi Phu TranNgoc Binh Nguyennnbinh@vnu.edu.vn2016-05-23T02:55:48Z2016-05-23T02:58:09Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1552This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15522016-05-23T02:55:48ZNghiên cứu và đề xuất một phương pháp bảo vệ bản quyền tài liệu sốNghiên cứu đề xuất phương pháp được phát triển trong đó một hình ảnh thủy vân xuất hiện trong một bản in và sau đó có thể được trích xuất bằng cách sử dụng máy quét để quét bản in và một phần mềm để khai thác thủy vân. Trong trường hợp này, phương pháp nhúng phải được thiết kế cẩn thận bởi vì cả hai quá trình in ấn và chụp xuất hiện nguyên nhân biến dạng mà làm cho khai thác thủy vân là một thách thức. Trọng tâm của nghiên cứu là kỹ thuật thủy vân mù, thông tin được nhúng là nhiều bít, đánh giá sự bền vững của các thuật toán được thử nghiệm trong một môi trường văn phòng, sử dụng thiết bị văn phòng.Viet Nguyen LuongVan Canh HoNhat Tien Trinhtientn@vnu.edu.vn2016-05-23T02:54:22Z2016-05-23T02:55:33Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1553This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15532016-05-23T02:54:22ZAn Efficient Ant Based Algorithm for Global Alignment of Protein-Protein Interaction NetworksGlobal aligning two protein-protein interaction networks is an essentially important task in bioinformatics. It is a challenging and widely studied research topic in recent years. Accurately aligned networks allow us to identify functional modules of proteins and/ororthologous proteins from which unknown functions of a protein can be inferred. In this article, we introduce an ant based global network alignment algorithm called ACOGA. The experiments show that the method that we proposed get better results than the introduced methods recently.Ngoc Ha TranXuan Huan Hoanghuanhx@vnu.edu.vn2016-05-23T02:53:30Z2016-05-23T02:54:05Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1554This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15542016-05-23T02:53:30ZNghiên cứu nâng cao hiệu quả và độ bảo mật cho các
hệ thống nhúngHệ thống nhúng (embedded system) được định nghĩa là một hệ thống chuyên dụng, có khả năng tự hành và được thiết kế tích hợp vào một hệ thống lớn hơn để thực hiện các chức năng chuyên biệt. Hệ thống nhúng bao gồm cả thiết bị phần cứng và phần mềm, thỏa mãn yêu cầu hoạt động theo thời gian thực. Hệ thống nhúng đặc trưng áp dụng trong lĩnh vực xây dựng và dân dụng là hệ thống điều khiển, giám sát và quản lý tòa nhà BMS (Building Management System). BMS bao gồm tổ hợp của các hệ thống nhúng thành phần và việc ứng dụng các hệ thống này giúp tăng tiện nghi cho người sử dụng, giảm chi phí vận hành của tòa nhà, tiết kiệm năng lượng và bảo vệ môi trường. Nghiên cứu này tập trung vào vấn đề bảo mật, vấn đề tối ưu hóa nguồn năng lượng và hiệu năng của hệ thống nhúng trong quản lý, giám sát tòa nhàThai Son Tran2016-05-23T02:52:32Z2016-05-23T02:53:14Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1555This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15552016-05-23T02:52:32ZNghiên cứu và ứng dụng ảnh LiDAR trong giám sát sol khí phát thải từ nông nghiệpÔ nhiễm không khí là một trong những vấn đề nghiêm trọng nhất trên thế giới, đặc biệt là tại các nước đang phát triển. Để kiểm soát mức độ ô nhiễm không khí, một trong những phương pháp được áp dụng là phân loại sol khí và các thành phần gây ô nhiễm, từ đó phát hiện các nguồn phát thải chính của chúng để có biện pháp xử lý.
Gần đây, kỹ thuật LiDAR phát triển được dùng trong nghiên cứu các quá trình hỗn loạn, các chu trình trong khí quyển, các hiện tượng khí tượng học như bão, áp thấp, các luồng gió dưới tác động của núi. LiDAR cho phép theo dõi sự thay đổi của mật độ khí thải, các lỗ thủng tầng ozone, cung cấp dữ liệu về ảnh hưởng của các hiệu ứng thời tiết, các đám bụi núi lửa và sự lan truyền xuyên châu lục của khí thải, bụi sa mạc, và khói của các vụ cháy rừng.
Định hướng của đề tài này là tập trung vào các thuật toán xử lý nguồn dữ liệu LiDAR để phân loại sol khí nói chung và sol khí có nguồn gốc từ các hoạt động nông nghiệp và áp dụng trong giám sát ô nhiễm không khí.Tuan Vinh TranThanh Thuy Nguyennguyenthanhthuy@vnu.edu.vnThi Nhat Thanh Nguyenthanhntn@vnu.edu.vn2016-05-23T02:51:01Z2016-05-23T02:51:58Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1556This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15562016-05-23T02:51:01ZNghiên cứu tích hợp mô hình dữ liệu trong trung tâm dữ liệu ngành dầu khí việt namTích hợp dữ liệu là vấn đề nghiên cứu có nhiều ứng dụng quan trọng trong Khoa học máy tính cũng như nhiều lĩnh vực của cuộc sống. Việc nghiên cứu về tích hợp dữ liệu đã được tiến hành trong nhiều thập kỷ gần đây và đã đạt được nhiều kết quả quan trọng. Tuy nhiên, với một số lĩnh vực đặc thù, các kết quả nghiên cứu về tích hợp dữ liệu còn nhiều hạn chế. Trong nghiên cứu này chúng tôi xem xét vấn đề tích hợp mô hình dữ liệu trong trung tâm dữ liệu ngành dầu khí Việt Nam. Từ việc khảo sát, đánh giá thực trạng công tác tổ chức, lưu trữ và sử dụng dữ liệu của các đơn vị trong Tập đoàn Dầu khí Việt Nam, chúng tôi xây dựng mô hình tích hợp dữ liệu cho ngành Dầu khí. Các kết quả chính đã đạt được bao gồm: a) xác định các mô hình dữ liệu từ các phần mềm quản lý dữ liệu thăm dò khai thác phổ biến hiện nay; b) xây dựng một Ontology về thăm dò khai thác dầu khí và c) đề xuất giải pháp tích hợp các ontology chuyên ngành dầu khí có sử dụng một số thuật toán học máy.Ngoc Trinh VuQuang Thuy Hathuyhq@vnu.edu.vnHung Son Nguyen2016-05-23T02:42:03Z2016-05-23T02:42:54Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1557This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15572016-05-23T02:42:03ZA Method for Automated Test Cases Generation from Sequence Diagrams and Object Constraint Language for Concurrent ProgramsModel- based testing plays a significant role in practice and a lot of researches on it has been investigated in recent years due to great benefits. There are some approaches for model- based testing: test data generation, test cases generation from behavior models and test scripts generation from abstract tests. Current research focuses on generating executable test cases from Unified Modeling Language (UML) sequence diagrams and object constraint language (OCL). In this paper we propose an automated test cases generation method from sequence diagrams, class diagrams, and object constraint language. The method supports UML 2.0 sequence diagrams including eight kinds of combined fragments describing control follow of systems. Test cases are generated with respect to the given concurrency coverage criteria. With strong concurrency coverage, generating exhaustive test cases for all concurrent interleaving sequences is exponential in size. The key idea of this method is to create selection of possible test scenarios in special case of exploring the message sequence with their possible interleaving in parallel or weak sequencing fragments. Test data for testing loop fragments is also generated. We implemented a tool to automate the proposed method and studied its feasibility and effectiveness. Experimental results show that the method can generate test cases on demand to satisfy a given concurrency coverage criterion and can detect up to 74.5% of seeded faults.Thi Dao VuNgoc Hung Phamhungpn@vnu.edu.vnViet Ha Nguyenhanv@vnu.edu.vn2016-05-23T02:38:08Z2017-01-17T02:21:27Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1558This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15582016-05-23T02:38:08ZKiến trúc mới cho giải pháp tái cấu hình mạng trên chipTrong báo cáo này chúng tôi giới thiệu một kiến trúc mới cho bộ định tuyến của mạng trên chip để thực hiện giải pháp tái cấu hình mạng trên chip (RNoC: Network-on-Chip). RNoC cung cấp khả năng tự thích ứng với sự thay đổi cấu hình mạng khi có một bộ định tuyến rời khỏi mạng mà vẫn bảo đảm chức năng truyền thông ổn định cho toàn hệ thống. Bẳng cách thay đổi thông tin tại trường tuyến để linh hoạt đường đi của thông tin khi hướng đi cố định bị chặn, giải pháp cập nhật định tuyến hạn chế được tác động nhiều giao tác truyền thông và tối ưu các chi phí thực thi trên chip. Để thực hiện hoạt động cập nhật thông tin định tuyến chúng tôi bổ sung một khối cổng ảo (RMport: Routing Modification) vào kiến trúc bộ định tuyến của mạng trên chip. Kiến trúc bộ định tuyến được thực hiện cho cấu trúc mạng dạng lưới 2D-mesh với giải thuật định tuyến tĩnh XY tại nguồn. Bộ định tuyến mạng trên chip tái cấu hình hoạt động ở hai chế độ: chế độ bình thường và chế độ tái cấu hình. Trong chế độ bình thường, bộ định tuyến đáp ứng yêu cầu chuyển tiếp thông tin theo đường định tuyến đã được xác định tại nguồn phát. Trong trường hợp hướng đi đến bộ định tuyến lân cận bị chặn, bộ định tuyến sẽ hoạt động ở chế độ tái cấu hình để cập nhật thông tin định tuyến thích ứng với cấu hình mạng hiện thời. Kết quả thực nghiệm được đánh giá dựa trên hiệu quả truyền thông với một số kiến trúc của một số công trình đã công bố.Van Thanh Vu Levulvt@husc.edu.vnXuan Tu Trantutx@vnu.edu.vn2016-05-23T02:28:04Z2016-05-23T02:29:14Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1559This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15592016-05-23T02:28:04ZApplication of Street Tracking Algorithm in a feedback configuration for an integrated INS/GPS navigation systemWhen satellite’s signal outage occurs, a single GPS receiver will be unable to provide a reliable solution, and an INS/GPS system would continue to use the raw IMU data to compute a solution. Several complementary methods have been proposed to provide a system with highly accurate position, velocity, and attitude in challenging GPS environments. In our previous study [1], we have proposed new algorithm called Street Tracking Algorithm (STA) to en- hance the correctness of the integrated system. However, this algorithm can on- ly improve the accuracy of the position of the vehicle due to its feed-forward configuration. This paper is an extended work of [1] when we proposed a feed- back scheme that combines STA with the conventional INS/GPS system. In this novel configuration, both velocity and position parameters are enhanced. The experimental result has showed that when GPS signal is lost, we can control the position error is around 2.5 m, and the velocity error is around 3.2 m/s.Van Thang NguyenDuc Trinh Chutrinhcd@vnu.edu.vnDuc Tan Trantantd@vnu.edu.vn2016-05-23T02:26:29Z2017-01-17T02:22:01Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1560This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15602016-05-23T02:26:29ZThiết kế và mô hình hoá bộ xử lý lô-gic mờ trong điều khiển tần số - điện ápTrong bài báo này, chúng tôi trình bày việc thiết kế một bộ điều khiển sử dụng thuật toán lô-gic mờ có khả năng dự đoán lưu lượng truyền thông của một bộ định tuyến trong mạng trên chip (NoC: Network-on-Chip). Từ đó, bộ điều khiển này sẽ tác động đến tần số và điện áp hoạt động của bộ định tuyến một cách phù hợp nhằm giảm thiểu năng lượng tiêu thụ của bộ định tuyến này theo phương pháp điều khiển tỷ lệ điện áp – tần số động (DVFS: Dynamic Voltage and Frequency Scaling) trong khi vẫn đảm bảo được hiệu năng hoạt động theo yêu cầu của bộ định tuyến. Bộ xử lý lô-gic mờ (FLP), phần lõi của thiết kế, đã được mô hình hoá bằng ngôn ngữ mô tả phần cứng VHDL. Hoạt động của bộ xử lý mờ được mô phỏng và kiểm chứng bằng phần mềm mô phỏng ModelSim của hãng Mentor Graphics.Hai Phong Phanhaiphongphan@gmail.comXuan Tu Trantutx@vnu.edu.vn2016-05-23T02:25:06Z2016-05-23T02:26:12Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1561This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15612016-05-23T02:25:06ZDistributed Coverage Control for Networked Multi-Robot Systems in Any EnvironmentDuy Hung Phamhungpd@vnu.edu.vnQuang Vinh Tranvinhtq@vnu.edu.vnTrung Dung Ngo2016-05-23T02:23:46Z2016-05-23T02:24:39Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1562This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15622016-05-23T02:23:46ZĐề xuất mô hình hệ thống phần cứng để định dạng và điều khiển búp sóng cho các anten thông minhVan Luyen TongVu Bang Giang Truonggiangtvb@vnu.edu.vn2016-05-23T02:22:31Z2016-05-23T02:23:26Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1563This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15632016-05-23T02:22:31ZThe Efficiency of Applying Compressed Sampling and Multi-Resolution into Ultrasound TomographyUltrasound tomography would allow ultrasound imaging to reach its full potential, compared to X-ray, MRI, etc. It is based on inverse scattering and has the capability to detect structures whose sizes are smaller than the wavelength of the incident wave, as opposed to conventional one using pulse-echo technique. Some material properties such as sound contrast and attenuation are very useful to detect small objects. The Distorted Born Iterative Method (DBIM) based on first-order Born approximation is an efficient diffraction tomography approach. The compressed sensing technique is utilized for the DBIM to obtain the high-quality ultrasound image. However, the image reconstruction process is quite long. In this paper, we proposed an approach to enhance the imaging quality and to reduce the imaging time by applying the compressed sensing technique along with the multi-resolution technique for the DBIM. The simulation results indicate that the imaging time is 33% reduced, the imaging quality is 83% improved.Quang Huy TranDuc Tan Trantantd@vnu.edu.vn2016-05-23T02:20:42Z2016-05-23T02:22:01Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1564This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15642016-05-23T02:20:42ZHigh gain low-noise amplifier design used for RF front end applicationThis paper presents the design and fabrication of a high gain low noise amplifier (LNA) at C-band, which suitable for RF front end application. In this paper, we propose a diagram of the two-stage cascade amplifier with different center frequency in order to create a good wide- band performance and high gain. The paper also proposes using negative feedback circuit to reduce the noise figure. The LNA has been fabricated on a PCB board with FR4 substrate using microstrip technology and pHEMT FET transistor amplifier with following specifications: Maximum overall gain of 26.046 dB, operating frequency from 4 GHz to 5 GHz, noise figure is about 1.2 dB, the reverse isolation of -29.5 dB, the LNA using a 5 V supply voltage respectively and total current consumptions of 20 mA. All the designed, simulated and fabricated processes were done using Agilent’ ADS 2009 package and machine LPKF Protomat C40.Van Hoi TranGia Duong Bachduongbg@vnu.edu.vn2016-05-23T02:17:06Z2016-05-23T02:19:58Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1565This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15652016-05-23T02:17:06ZSub-100nm ferroelectric-gate thin film transistor fabricated by two-step patterning methodFerroelectric-gate thin film transistor (FGT) which uses an active oxide-semiconductor channel and a ferroelectric-gate insulator has attracted wide attention for the application of a new nonvolatile memory because of its prominent features such as simple device structure, high-speed operation and low power consumption. Recently, we have reported on demonstration of the of FGTs operation. However, the FGTs developed have channel lengths (LDS) more than 100 nm, which should be reduced for high-density storage in integration circuits.1-2) In this paper, we will present a new method to fabricate the sub-100 nm FGT, of which the source-drain gap would be surely created, in principle, comparing with the conventional patterning method. Electrical properties and memory functionalities of the fabricated sub-100nm FGTs will be investigated and discussed in detail.Hong Minh DoDuc Thang Phampdthang@vnu.edu.vnNguyen Quoc Trinh Buitrinhbnq@vnu.edu.vn2016-05-23T02:14:32Z2016-05-23T02:15:57Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1566This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15662016-05-23T02:14:32ZNonlinear dynamic and stability analysis of ES-FGM plates on elastic foundationSince its first introduction in 1984 by a group of material scientists in Japan, functionally graded materials (FGMs) have attracted considerable attention in many engineering applications namely extremely high temperature resistant materials. Eccentrically stiffened FGM (ES-FGM) was firstly studied in 2011 [1]. After that, ES-FGM was attracted and studied more by many authors; however, their studies mainly used classical theory and did not study the effects of temperature on stiffeners. This paper presents an analytical approach to investigate the nonlinear dynamic response and stability analysis of centrically stiffened FGM plates on elastic foundation using both of the first order shear deformation plate theory and stress function. The ES-FGM plates are assumed to rest on elastic foundation and subjected to mechanical, thermal loads in thermal environment.Hong Cong PhamDinh Duc Nguyenducnd@vnu.edu.vn2016-05-23T02:13:18Z2016-05-23T02:14:05Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1567This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15672016-05-23T02:13:18ZOn the nonlinear stability of eccentrically stiffened functionally graded annular spherical segmentThe nonlinear stability of eccentrically stiffened functionally graded (FGM) annular spherical segment resting on elastic foundations under external pressure is studied analytically. The FGM annular spherical segments are reinforced by eccentrically longitudinal and transversal stiffeners made of full metal or ceramic depending on situation of stiffeners at metal-rich or ceramic-rich side of the shell respectively. Based on the classical thin shell theory, the governing equations of FGM annular spherical segments are derived. Approximate solutions are assumed to satisfy the simply supported boundary condition of segments and Galerkin method is applied to study the stability. Numerical results are given to evaluate effects of homogeneous, dimensional parameters, outside stiffeners, elastic foundations to the stability of the structures.Thi Thuy Anh Vuvuanhthuy206@gmail.comDinh Duc Nguyenducnd@vnu.edu.vn2016-05-23T01:28:55Z2016-05-23T01:31:39Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1568This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15682016-05-23T01:28:55ZResearch, manufacturing optimal structure sensor measure the low magnetic field structure Wheatstone bridge base on anistropic magnetoresistance effectsFabrication and study of sensors applied to measure low magnetic fields whose the Wheatstone structure basing on anisotropic magnetoresistance effects. The configuration optimatization of sensors was conducted by varying the thickness of NiFe layers (5, 10, 15 nm) as well as the structure of resistive bars. Two types of sensor with the sizes of 50×250 μm and 10×250 μm were examined. The results revealed the significant dependence of sensor signals on sensor shape anisotropy. The resistivie difference (ΔR), the sensitity (SH) and the shape anisotropy were observed to increase as decreasing the thickness of NiFe layer. The highest values (ΔR and SH were obtained to be 10Ω and 0.88 Ω/Oe (~ 0,88 mV/Oe), respectively) were found in the sensor with the size of 10×250 μm and 5 nm-thickness. The function of the output voltage versus the Earth's magnetic field and the sensor axis was fitted to be V = A + B*cosα (A, B are empirical constants), and Sα = 8.8 (μV/deg.)Khac Quynh LeDinh Tu Buibuidinhtu@vnu.edu.vnQ. Viet D.T. Thuy N.Xuan Toan NguyenMau Danh TranHuu Duc Nguyenducnh@vnu.edu.vnThi Huong Giang Dogiangdth@vnu.edu.vn2016-05-23T01:25:57Z2016-05-23T01:26:56Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1569This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15692016-05-23T01:25:57ZChế tạo, nghiên cứu cấu trúc và tính chất của một số hệ màng mỏng hợp kim AuFeCông nghệ cấy ion bằng máy gia tốc hiện nay là một trong những phương pháp rất hiện đại trong việc chế tạo và nghiên cứu tính chất của vật liệu, đặc biệt trong việc chế tạo các vật liệu khó hòa tan như H, C ...vào các màng mỏng kim loại. Màng mỏng hợp kim AuFe được chế tạo bằng phương pháp bốc bay nhiệt trong chân không. Sau đó, bằng máy gia tốc pelletron 5SDH-2 chúng tôi đã cấy ion C để tạo nên 5 hệ mẫu AuFe+C với nồng độ C khác nhau. Các hình thái cấu trúc, các tính chất điện, từ, quang học cũng đã được chúng tôi khảo sát. Các kết quả cho thấy rằng, màng mỏng AuFe được hình thành với tỉ lệ 1:3 và tương đối đồng đều. Các màng mỏng AuFe+C đã có sự thay đổi kích thước ô mạng, đặc biệt độ dẫn tương đối của màng này lớn hơn với màng AuFe gốc và thể hiện tính dẫn điện khá tốt, đỉnh hấp thụ cực đại nằm trong vùng ánh sáng tím và đặc biệt là sự xuất hiện của đỉnh phát xạ ở khoảng 415nm. Ngoài ra, chúng tôi còn khảo sát thêm một số tính chất khác của màng mỏng này như tính chất từ tại vùng nhiệt độ từ 80K đến 1000K.Khac Thuan NguyenNam Nhat Hoangnhathn@vnu.edu.vn2016-05-23T01:16:42Z2016-05-23T01:18:11Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1571This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15712016-05-23T01:16:42ZNonlinear Dynamic Response and Vibration of Imperfect Shear Deformable Functionally Graded Plates Subjected to Blast and Thermal LoadsBased on Reddy’s higher-order shear deformation plate theory, this paper presents an analysis of the nonlinear dynamic response and vibration of imperfect functionally graded material (FGM) thick plates subjected to blast and thermal loads resting on elastic foundations. The material properties are assumed to be temperature-dependent and graded in the thickness direction according to a simple power-law distribution in terms of the volume fractions of the constituents. Numerical results for the dynamic response and vibration of the FGM plates with two cases of boundary conditions are obtained by the Galerkin method and fourth-order Runge- Kutta method. The results show the effects of geometrical parameters, material properties, imperfections, temperature increment, elastic foundations and boundary conditions on the nonlinear dynamic response and vibration of FGM plates.Duc Tuan NgoPhuong TranQuoc Quan TranDinh Duc Nguyenducnd@vnu.edu.vn2016-05-23T01:14:46Z2016-05-23T01:23:49Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1572This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15722016-05-23T01:14:46ZPhát hiện lượng hạt từ kích thước nano bằng cảm biến từ trường siêu nhạyPhát hiện các hạt siêu thuận từ kích thước nano đòi hỏi phải có một cảm biến từ trường với độ nhạy cao, độ phân giải lớn và tỷ số tín hiệu/nhiễu cao. Chúng tôi đã chế tạo thành công cảm biến dựa trên hiệu ứng từ-điện (ME - magnetoelectric) trên vật liệu tổ hợp Metglas/PZT đạt độ phân giải trong khoảng nanoTesla. Báo cáo này trình bày các kết quả đo đạc thực nghiệm trên dung dịch chứa các hạt siêu thuận từ Fe3O4 kích thước 20 nm ở các nồng độ khác nhau sử dụng cảm biếm tự chế tạo. Kết quả đo đạc thực nghiệm với cảm biến tự chế tạo đã phát hiện được lượng rất nhỏ (~100 nanogram) các hạt siêu thuận từ mà các phương pháp đo không tiếp xúc thông thường không phát hiện được. Các kết quả nghiên cứu này mở ra khả năng chế tạo các cảm biến sinh học dùng trong các bộ KIT nhận biết và đo đạc định lượng các phần tử sinh học có đánh dấu từ rất nhỏ với độ chính xác và độ tin cậy cao.Xuan Toan NguyenXuan Dang DangKhac Quynh LeDinh Tu Buibuidinhtu@vnu.edu.vnHuu Duc Nguyenducnh@vnu.edu.vnThi Huong Giang Dogiangdth@vnu.edu.vn2016-05-23T01:09:24Z2016-05-23T01:12:06Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1573This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15732016-05-23T01:09:24ZOptical Property and Photoelectrical Performance of a Low-Bandgap Conducting Polymer Incorporated With Quantum Dots Used for Organic Solar CellsBy using spin-coating technique, a low bandgap conjugated polymer, poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopen-ta[2,1-b;3,4-b′]dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT) and its composite thin films have been prepared. The optical absorption and photoconductive properties with over a wide spectral range, from 350 to 950 nm, were characterized. The obtained results showed that PCPDTBT:10 wt% CdSe composite is the most suitable for efficient light-harvesting in polymer-based photovoltaic cells. The photoelectrical conversion efficiency (PCE) of the device with a multilayer structure of ITO/PEDOT/ PCPDTBT:CdSe /LiF/Al reached a value as large as 1.34% with an open-circuit voltage (Voc) = 0.57 V, a short-circuit current density (Jsc) = 4.29 mA/cm2, and a fill factor (FF) = 0.27. This suggests a useful application in further fabrication of quantum dots/polymers based solar cells.Thi Thao TranQuang Trung TranVan Truong VoNang Dinh Nguyendinhnn@vnu.edu.vn2016-05-22T14:15:42Z2016-05-22T14:16:14Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1519This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15192016-05-22T14:15:42ZAn approach to verifying consistency of software refactoring processIn software development, refactoring is a process that improves the system internal structure without altering its external behavior. Applying design patterns, which is the common reusable solution of several kinds of problems, is widely adopted in refactoring. And, the combination of refactoring and design patterns has established a revolution approach in software re-engineering. It, however, raises a challenged issue that the software model may not preserve some cer- tain behavioral properties. In this paper, we propose a new approach to checking the consistency between original model and its evolution (the model after applying design pattern). To this aim, we employ Unified Modeling Language (UML) to modeling system, and Object Constraint Language (OCL) to represent the system requirement. In additional, we construct a set of consistent rule which uses to checking whether the system can preserve its behavior or not. We also illus- trate the checking approach in a case study of Adaptive Road Traffic Control System.Thi Huong DaoHong Anh LeNinh Thuan Truongthuantn@vnu.edu.vn2016-05-22T14:14:21Z2016-05-22T14:15:15Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1518This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15182016-05-22T14:14:21ZBuilding the Local Spatial Data Infrastructure for the Northeast and Northwest of VietnamNational Spatial Data Infrastructure (NSDI) is the backbone of the development of e-government for a country. Since 2011, Vietnam began to pay attention to NSDI. Till now, the is no significant progress in implementation of NSDI except a common research between World Bank and Ministry of Natural Resources and Environment on strategic planning of NSDI and another research on making policy for building NSDI. In this paper, we present our research on the construction of the Local SDI (LSDI) for the Northeast and the Northwest of Vietnam. Our hypothesis is that the success of this LSDI will be a good lesson for building NSDI in the future. The reason why we selected the Northeast and Northwest because it is a large area with a total area of approximately 115,700km2 that is nearly 1/3 of Vietnam. Moreover, the Northeast and the Northwest comprehensively contain of topographical and morphological characteristics of nature, economics and society of Vietnam. NSDI is considered consisting of seven components: (i) spatial data; (ii) standards; (iii) Access to data; (iv) technology; (v) policy – legislation; (vi) organization – institution; (vii) partnership. In this research we only focused on four technical components which are spatial data, standards, access to data and technology. We collected spatial data from three sources: (i) existing spatial data and framework spatial data from Government and Local Government; (ii) existing remote sensing data from the NASA, USGS; (iii) Update remote sensing data from MODIS/NPP ground station at our university. We used open source platforms for building LSDI. Regarding to the access to data, we have organized spatial data in a data warehouse architecture to develop BI (Business Intelligence) tools. A pilot tool is for automatically generating annual reports on 43 indicators of sustainable development issued by the Prime Minister. For the future work, we will evaluate this LSDI from the viewpoints of end-users from government, local government and citizens.Ngoc Thanh DaoQuang Hung Buihungbq@vnu.edu.vnHai Chau Nguyenchaunh@vnu.edu.vnVan Vuong Nguyen2016-05-22T13:08:23Z2016-05-28T10:02:30Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1517This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15172016-05-22T13:08:23ZKiểm chứng phần mềm dựa trên phân tích chương trìnhViệc phát triển phần mềm yêu cầu các bước thực hiện chặt chẽ, độ chính xác cao nhằm đáp ứng đúng, đủ yêu cầu người sử dụng. Tuy nhiên đội ngũ phát triển phần mềm cũng không thể kiểm soát hết các lỗi, các vấn đề phát sinh khi phần mềm đưa vào sử dụng.
Đề tài tập trung vào việc nghiên cứu các phương pháp nhằm phân tích một số thuộc tính của chương trình, từ đó xây dựng các công cụ phân tích chương trình từ nhiều khía cạnh khác nhau, đưa ra thông tin cho người phát triển phần mềm đảm bảo tính đúng đắn cho chương trình.Anh Tu BuiNinh Thuan Truongthuantn@vnu.edu.vn2016-05-22T13:05:06Z2016-05-22T13:07:42Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1515This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15152016-05-22T13:05:06ZKiểm thử dựa trên mô hình với cách tiếp cận mô hình hóa miền chuyên biệtTrong phát triển phần mềm, kiểm thử là một quy trình quan trong và không thể thiếu để phát triển một hệ thống phần mềm tin cậy và có chất lượng cao. Để có thể giảm chi phí, tăng chất lượng cho hoạt động kiểm thử một hướng tiếp cận cho kiểm thử phần mềm là kỹ thuật kiểm thử dựa trên mô hình (Model-Based Tesing - MBT). Kỹ thuật này cho phép sinh tự động các ca kiểm thử và thực thi tự động các ca kiểm thử từ mô hình. Trong nghiên cứu này, chúng tôi tập trung vào nghiên cứu quy trình sinh tự động (Automated Test Cases Generation) các ca kiểm thử từ mô hình với hướng tiếp cận mô hình hóa miền chuyên biệt (Domain-Specific Modeling - DSM) cho vấn đề sinh các ca kiểm thử từ đặc tả ca sử dụng (Use Case Specification). Đặc tả ca sử dụng được viết trong tài liệu đặc tả phần mềm bằng ngôn ngữ tự nhiên vì vậy mà việc sinh tự động các ca kiểm thử từ đặc tả này vẫn còn nhiều thách thức. Chất lượng sinh các ca kiểm thử phụ thuộc vào tiêu chí phủ các ca kiểm thử. Nghiên cứu này của chúng tôi tập chung vào nghiên cứu và đề xuất phương pháp sinh tự động các ca kiểm thử từ đặc tả ca sử dụng với độ phủ các ca kiểm thử đạt được các tiêu chí phủ kiểm thửThi Minh Hue ChuNgoc Binh Nguyennnbinh@vnu.edu.vnDuc Hanh Danghanhdd@vnu.edu.vn2016-05-21T03:17:03Z2016-05-21T03:21:21Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1514This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15142016-05-21T03:17:03ZAn automated system for monitoring online social media in educational areaXuan Duc Nguyenducnx_58@vnu.edu.vnHong Quang Lequanglh_58@vnu.edu.vnViet Quan Trong Letronglvq_57@vnu.edu.vnDuc Nam Nguyennamnd_58@vnu.edu.vnLe Minh Nhat Trannhattlm_58@vnu.edu.vnBao Son Phamsonpb@vnu.edu.vnXuan Hieu Phanhieupx@vnu.edu.vn2016-05-20T09:07:15Z2016-05-20T09:08:13Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1492This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/14922016-05-20T09:07:15ZMeboo-the health & medical services management applicationThe Huy Nguyenhuynt_57@vnu.edu.vnDuc Thinh Nguyenthinhnd_57@vnu.edu.vnNam Phong Nguyenphongnn_57@vnu.edu.vnNguyen Ngoc Phungngocpn_57@vnu.edu.vnAnh Hoang Truonghoangta@vnu.edu.vn2016-05-20T09:05:44Z2016-05-20T09:06:56Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1510This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15102016-05-20T09:05:44ZNghiên cứu cố định protein BSA lên bề mặt polymer PDMS chức năng định hướng ứng dụng trong chế tạo cảm biến sinh họcThi Ngoc TranHong Nhung LuongThi Hien Lelehien@vnu.edu.vnThi Huyen Vu2016-05-20T09:04:35Z2016-05-20T09:05:34Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1509This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15092016-05-20T09:04:35ZPhân tích ổn định cơ và nhiệt của panel nón FGM có gân gia cường trên nền đàn hồi trong môi trường nhiệtMinh Anh Vuvuminhanhhp@gmail.comDinh Quang Vuquangvd2510@gmail.comDinh Duc Nguyenducnd@vnu.edu.vn2016-05-20T09:03:07Z2016-05-20T09:04:21Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1508This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15082016-05-20T09:03:07ZPhân tích ổn định phi tuyến của panel trụ làm bằng vật liệu composite FGM có gân gia cường trên nền đàn hồi chịu tải cơ, nhiệt và cơ – nhiệt kết hợpVan Anh Trananhtv0511@gmail.comVan Quyen Nguyenvanquyen.uet@gmail.comDinh Duc Nguyenducnd@vnu.edu.vn2016-05-20T09:01:40Z2016-05-20T09:02:57Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1507This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15072016-05-20T09:01:40ZNghiên cứu, phân tích và viết chương trình phát hiện các sóng trên điện tâm đồ ứng dụng trong chẩn đoán bệnh về timNhu Chi Trantrannhuchi@gmail.comDuy BuiKhanh NguyenHong Quan DauDuc Trinh Chutrinhcd@vnu.edu.vn2016-05-20T09:00:46Z2016-05-20T09:01:32Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1506This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15062016-05-20T09:00:46ZThiết kế máy phát điện chuyển động thẳng công suất 5KWVan Tien Đoannangvang02041994@gmail.comThe Ba Dangbadt@vnu.edu.vn2016-05-20T08:59:53Z2016-05-20T09:00:37Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1505This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15052016-05-20T08:59:53ZDOA estimation systems in correlated environment: Asym-AWPC-CS and Asym-AWPC-SMLThi Phuong Nguyenntphuong169@gmail.comThi Thuy Quynh Tranquynhttt@vnu.edu.vn2016-05-20T08:58:46Z2016-05-20T08:59:43Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1504This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15042016-05-20T08:58:46ZMonitoring and classification of cow activities using three-dimensional accelerometersThi Huyen Nga Nguyenhuyennga154@gmail.comThi Thu Ha Lelethithuha25@gmail.comBa Cuong Doandoanbacuongisp13@gmail.comDuc Tan Trantantd@vnu.edu.vn2016-05-20T08:57:15Z2016-05-20T08:58:36Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1503This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15032016-05-20T08:57:15ZAn automated system for monitoring online social media in educational areaXuan Duc Nguyenducnx_58@vnu.edu.vnHong Quang Lequanglh_58@vnu.edu.vnViet Quan Trong Letronglvq_57@vnu.edu.vnDuc Nam Nguyennamnd_58@vnu.edu.vnLe Minh Nhat Trannhattlm_58@vnu.edu.vnBao Son Phamsonpb@vnu.edu.vnXuan Hieu Phanhieupx@vnu.edu.vn2016-05-20T08:43:30Z2016-05-20T08:44:16Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1502This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15022016-05-20T08:43:30ZA solution for automatically scanning web vulnerabilityHuu Tung Nguyenhtung.nht@gmail.comVan Giap Legiaplvk57@gmail.comNgoc Hoa Nguyenhoa.nguyen@vnu.edu.vn2016-05-20T08:42:29Z2016-05-20T08:43:21Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1501This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15012016-05-20T08:42:29ZSAT Encoding dựa trên mẫu tìm kiếm giải trò chơi Loogic HitoriVan Duy Dododuy101294@gmail.comVan Khanh Tokhanhtv@vnu.edu.vn2016-05-20T08:41:19Z2016-05-20T08:42:16Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1500This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15002016-05-20T08:41:19ZHệ thống tư vấn xã hội dựa trên phân tích ý định và hành vi người sử dụngThi Hong Vuonghongvt_57@vnu.edu.vnMinh Duc Nguyenduchell.uet.vnu@gmail.comThi Cam Van NguyenMai Vu Tranvutm@vnu.edu.vn2016-05-20T08:38:22Z2016-05-20T08:40:59Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1499This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/14992016-05-20T08:38:22ZPhương pháp và công cụ phân tích ảnh hưởng của sự thay đổi mã nguồn cho các ứng dụng J2EE6Cong Hung Nguyenhungnc_57@vnu.edu.vnQuynh Mai NguyenNgoc Hung Phamhungpn@vnu.edu.vnDinh Hieu Vohieuvd@vnu.edu.vn2016-05-20T08:37:16Z2016-05-20T08:38:02Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1498This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/14982016-05-20T08:37:16ZPhương pháp và công cụ kiểm thử tự động cho các ứng dụng C/C++Tuan Anh Duonganhdt_57@vnu.edu.vnDuc Vu SamNgoc Hung Phamhungpn@vnu.edu.vn2016-05-20T08:35:53Z2016-05-20T08:37:01Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1497This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/14972016-05-20T08:35:53ZHealthkee: a symptom checker and personalized health information serviceVan Giap Nguyengiapnv_57@vnu.edu.vnViet Anh Vuanhvv_57@vnu.edu.vnDinh Minh Leminhld_57@vnu.edu.vnXuan Hieu Phanhieupx@vnu.edu.vn2016-05-20T08:34:12Z2016-05-20T08:35:24Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1495This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/14952016-05-20T08:34:12ZXây dựng mô hình và hệ thống dự báo dịch tả khu vực Hà Nội dựa trên kỹ thuật khai phá dữ liệuThi Oanh Ngooanhnt_57@vnu.edu.vnChi Quang Chuquangcc_57@vnu.edu.vnThi Huyen Trang Laitranglth_57@vnu.edu.vnThi Dung Nguyendungnt_57@vnu.edu.vnQuang Thuy Hathuyhq@vnu.edu.vnHoang Quynh Lelhquynh@gmail.com2016-05-20T07:49:16Z2016-05-20T08:33:08Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1494This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/14942016-05-20T07:49:16ZOn the design and development of a mobile virtual assistant for Vietnamese (VAV)Thi Hai Yen Vuongyenvth_57@vnu.edu.vnVan Hop Nguyenhopnv_57@vnu.edu.vnQuang Vu Duongvudq_57@vnu.edu.vnThi Thu Phithupt_57Thac Thong NguyenQuoc Tuan TruongXuan Hieu Phanhieupx@vnu.edu.vn2016-05-20T06:51:36Z2016-05-20T07:14:04Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1496This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/14962016-05-20T06:51:36ZA hybrid approach for Vietnamese word segmentationTuan Phong Nguyentuanphong94@gmail.comAnh Cuong Lecuongla@vnu.edu.vnNguyen Khoi Lekhoi.n.le@vnu.edu.vn2016-05-15T14:27:14Z2017-01-17T02:49:13Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1512This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15122016-05-15T14:27:14ZRouting-path Tracking and Updating Mechanism in Reconfigurable Network-on-ChipsAs the rapid advancement in semiconductor technology leads to shrinking of transistor sizes and the integration scale is over one billion transistors, Reconfigurable Network-on-Chips becomes a new methodology providing adaptive infrastructure resources as well as flexible network protocols to adapt to dynamic environment. In this paper, we propose a routing-path tracking and updating mechanism for reconfigurable Network-on-Chips. The hardware architectures used to implement the proposed mechanism such as modified RNoC routers and Network Interfaces are introduced. With this routing-path tracking and updating mechanism, packet transmission delay can be reduced from 4.92% to 33.33% depending on the data structures.Thi Thuy Nguyenthuynguyen@vnu.edu.vnVan Thanh Vu Levulvt@husc.edu.vnKiem Hung Nguyenkiemhung@vnu.edu.vnXuan Tu Trantutx@vnu.edu.vn2016-05-14T14:44:46Z2017-01-17T02:20:44Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1511This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/15112016-05-14T14:44:46ZUltra Low-Power and Low-Energy 32-bit Datapath AES Architecture for IoT ApplicationsIn this paper, we propose a novel AES microarchitecture with 32-bit datapath optimized for low-power and low-energy consumption targeting IoT applications. The proposed design uses simple shift registers for key/data storage and permutation to minimize the area, and the power/energy consumption. These shift registers also minimize the control logics in the key expansion and the encryption path. The proposed architecture is further optimized for area and/or power/energy consumption by selecting a suitable implementation of S-boxes and applying the clock gating technique. The implementation results in TSMC 65nm technology show that our design can save 20% of area or 20% of energy per bit at the same area when compared with the current 32-bit datapath designs. Our design also occupies smaller core area with lower energy per bit and at least 4 times higher in throughput in comparison with other 8-bit designs in the same technology node.Duy Hieu Buihieubd@vnu.edu.vnDiego Puschinidiego.puschini@cea.frSimone Bacles-MinSimone.BACLES-MIN@cea.frEdith BeigneXuan Tu Trantutx@vnu.edu.vn2016-02-16T03:27:16Z2016-02-16T03:27:16Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1485This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/14852016-02-16T03:27:16ZVật liệu polymer compozit sợi thủy tinhDinh Duc Nguyenducnd@vnu.edu.vn2016-02-15T02:55:33Z2017-01-17T02:13:33Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/1484This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/14842016-02-15T02:55:33ZAn Efficient Implementation of Advanced Encryption Standard on the Coarse-grained Reconfigurable ArchitectureThe Advanced Encryption Standard (AES) is currently considered as one of the best symmetric-key block ciphers. The hardware implementation of the AES for hand-held mobile devices or wireless sensor network nodes is always required to meet the strict constraints in terms of performance, power and cost. Coarse-grained reconfigurable architectures are recently proposed as the solution that provides high flexibility, high performance and low power consumption for the next-generation embedded systems. This paper presents a flexible, high-performance implementation of the AES algorithm on a coarse-grained reconfigurable architecture, called MUSRA (Multimedia Specific Reconfigurable Architecture). First, we propose a hardware-software partitioning method for mapping the AES algorithm onto the MUSRA. Second, the parallel and pipelining techniques are considered thoughtfully to increase total computing throughput by efficiently utilizing the computing resources of the MUSRA. Some optimizations at both loop transformation level and scheduling level are performed in order to make better use of instruction-, loop- and task- level parallelism. The proposed implementation has been evaluated by the cycle-accurate simulator of the MUSRA. Experimental results show that the MUSRA can be reconfigured to support both encryption and decryption with all key lengths specified in the AES standard. The performance of the AES algorithm on the MUSRA is better than that of the ADRES reconfigurable processor, Xilinx Virtex-II, and the TI C64+ DSP.Kiem Hung Nguyenkiemhung@vnu.edu.vnXuan Tu Trantutx@vnu.edu.vn