VNU-UET Repository: No conditions. Results ordered -Date Deposited. 2024-03-29T08:26:18ZEPrintshttp://eprints.uet.vnu.edu.vn/images/sitelogo.pnghttps://eprints.uet.vnu.edu.vn/eprints/2020-12-23T02:52:34Z2020-12-23T02:52:59Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4312This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/43122020-12-23T02:52:34ZNghiên Cứu, Thiết Kế, Chế Tạo Và Thử Nghiệm Hệ Thống Mạch Đo Di Động Cho Cảm Biến Chất Lỏng IonBáo cáo này trình bày kết quả nghiên cứu phát triển hệ thống mạch đo nhỏ gọn (portable), ứng dụng cho đo đạc các cảm biến đo biến dạng dải rộng sử dụng chất lỏng ion. Hệ thống mạch đo được thiết kế dựa trên phương pháp đo 4 điểm. Một tín hiệu hình sine được tạo ra bởi mạch cầu Wien đi qua nguồn dòng Howland trước khi được đưa đến hai đầu của cảm biến. Điện trở của cảm biến được xác định thông qua giá trị điện áp đo được trên hai đầu cảm biến và giá trị của dòng điện đã được cài đặt từ nguồn dòng Howland. Một vi điều khiển được sử dụng để hiển thị và thu thập dữ liệu thông qua module Bluetooth thương mại giá rẻ. Hoạt động của hệ đo được mô phỏng trên phần mềm mô phỏng Multisim và thực nghiệm thực tế cho kết quả điện trở đo được có độ chính xác cao (99.51%), hệ thống có dải đo lớn (0 ÷ 700kΩ) và dải tần làm việc rộng (0 ÷ 200kHz). Hệ thống mạch đo được chế tạo và kết nối với cảm biến đo biến dạng dải rộng dựa trên chất lỏng ion ứng dụng cho các thiết bị mặc được (wearable). Kết quả thực nghiệm chứng tỏ hệ thống đã phát triển nhỏ gọn, làm việc ổn định, đáp ứng bài toán đo lường cho cảm biến biến dạng sử dụng cho các ứng dụng thực tế.Nhu Chi Trantrannhuchi@vnu.edu.vnTien Manh Phammanhpt1298@gmail.comThi Thanh Van Nguyenvanntt@vnu.edu.vnThanh Tung Buitungbt@vnu.edu.vnDuc Trinh Chutrinhcd@vnu.edu.vnNgoc An Nguyenngocan@vnu.edu.vn2020-12-16T03:02:38Z2020-12-16T03:02:38Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4271This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/42712020-12-16T03:02:38ZWearable Fluidic Strain Sensor for Human Motion SensingA strain sensor with high flexibility using ionic liquid is proposed for sensing movements of human body. The resistance strain sensor is constructed from a silicon tube filled fully with a mixture of aqueous sodium chloride and glycerin sealed gold-coated electrodes. When an external force is applied to the sensor, the silicon tube deforms resulting in a change in the sensor resistance value. The proposed sensor was fabricated and experimentally characterized under several working conditions. Good performance was demonstrated in detecting the movement of human leg and fingers. The proposed simple sensor has high potential in wearable applications.Nhu Chi Trantrannhuchi@vnu.edu.vnNgoc An Nguyenngocan@vnu.edu.vnThanh Van Dauv.dau@griffith.edu.auVan Chieu Levanchieu@gmail.comDuc Trinh Chutrinhcd@vnu.edu.vnThanh Tung Buitungbt@vnu.edu.vn2020-12-08T09:36:24Z2020-12-08T09:36:24Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4182This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/41822020-12-08T09:36:24ZNghiên cứu phát triển robot xây dựng bản đồ và định vị đồng thời trên nền tảng ROSBài báo trình bày nghiên cứu, thiết kế một robot có khả năng xây dựng bản đồ và định vị đồng thời (SLAM) trên nền tảng mã nguồn mở của hệ điều hành robot (ROS). Với kích thước nhỏ gọn và chi phí thấp, robot có khả năng tự động di chuyển, thu dữ liệu của môi trường, xây dựng bản đồ và định vị vị trí trên bản đồ của trong môi trường trong nhà có cấu trúc không xác định. Hiệu quả hoạt động của robot được kiểm nghiệm thông qua các đánh giá thực nghiệm trong môi trường thực.Hoang Anh Phananh.ph@vnu.edu.vnThi Thanh Van Nguyenvanntt@vnu.edu.vnHuu Quoc Dong Trandongtran.robotics@gmail.comDuy Nam Buiduynam.robotics@gmail.comTien Dat Vuv.d98@gmail.com2020-12-08T09:31:44Z2020-12-08T09:31:44Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4154This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/41542020-12-08T09:31:44ZNghiên cứu thiết kế mô phỏng cảm biến vận tốc góc dạng khí hai bậc tự do
hoạt động dựa trên hiệu ứng dòng xả coronaBài báo này trình bày về thiết kế mô phỏng một cấu hình cảm biến vận tốc góc dạng khí hai bậc tự do hoạt động dựa trên hiệu ứng dòng xả corona. Một cấu hình ba cặp điện cực kim – vòng được đề xuất để tạo ra một luồng gió ion ổn định trong buồng làm việc của cảm biến. Khi có vận tốc góc tác dụng, luồng gió ion bị lệch tỷ lệ với vận tốc góc tác dụng. Độ lệch của luồng gió ion được cảm nhận bởi
các dây nhiệt điện trở đặt tại các vị trí thích hợp để đo vận tốc góc tác dụng theo hai trục. Cảm biến được thiết kế bằng phần mềm 3D Solidword và mô phỏng số hoạt động của cảm biến. Bằng cách sử dụng luồng gió ion, cảm biến vận tốc góc không có các bộ phận dao động, nhỏ gọn nhưng chắc chắn, do đó, có độ bền cơ học cao và tiêu thụ ít năng lượng.Van Ngoc Trantvngoc84@gmail.comThanh Van Dauv.dau@griffith.edu.auThu Hang Nguyenhang021197@gmail.comDuc Trinh Chutrinhcd@vnu.edu.vnThanh Tung Buitungbt@vnu.edu.vn2020-12-08T09:31:34Z2020-12-08T09:46:39Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4156This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/41562020-12-08T09:31:34ZHệ thống vi cơ điện tử MEMS và ứng dụngBáo cáo này trình bày tổng quan về vi cơ điện tử MEMS, một lĩnh vực
khoa học liên ngành dựa trên nền tảng của ngành vi điện tử và vi chế tạo. Các linh kiện MEMS hiện nay được sử dụng rộng rãi trong xã hội như cám biến gia tốc, cảm biến góc, cảm biến áp xuất, cảm biến sinh học,... Báo cáo cũng trình bày tóm tắt một số định hướng nghiên cứu của nhóm nghiên cứu Vi cơ điện tử và vi hệ thống, tại Khoa Điện tử- Viễn thông, Trường Đại học Công nghệ, Đại học Quốc gia Hà nội.Ngoc An Nguyenngocan@vnu.edu.vnVan Ngoc Trantvngoc84@gmail.comDinh Tiep Dangdangtiep.2011@gmail.comQuang Loc Dolocdq@gmail.comThi Thuy Ha Trantttha@gmail.comDac Hai Nguyenhaind75@gmail.comVan The Vuthevutb@gmail.comNhu Cuong Nguyencuongnn241@gmail.comNgoc Thao Phamthao.pham@uet.edu.vnThanh Tung Buitungbt@vnu.edu.vnDuc Trinh Chutrinhcd@vnu.edu.vn2020-12-08T09:31:01Z2020-12-08T09:31:01Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4152This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/41522020-12-08T09:31:01ZCharacterization of Gelatin and PVA Nanofibers Fabricated Using Electrospinning ProcessNanofibers has been recently received tremendous attention from researchers due to its advantages. Among the fabrication methods for nanofibers, electrospinning appears to be an intriguing technique, allowing the fabrication of nanofibers in a simple and inexpensive way. In this paper, we prepared and fabricated nanofibers using the electrospinning process with two polymers: gelatin and PVA. The process and the fabricated fibers were examined under scanning electron microscope. The effect of the polymeric concentration was also studied. The experimental results indicate that nanofibers were successfully fabricated, and higher polymer concentration leads to the uniformity of the fibers. In addition, the nanofiber mat with silver nanoparticles was successfully fabricated, opening the potential for medical applications of the fabricated fibers.Nhu Cuong Nguyencuongnn241@gmail.comThi Nhung Vunhungvuthi3011@gmail.comHoang Nam Nguyennamnh@hus.edu.vnNgoc Thao Phamthao.pham@uet.edu.vnDuc Trinh Chutrinhcd@vnu.edu.vnThanh Van Dauv.dau@griffith.edu.auThanh Tung Buitungbt@vnu.edu.vn2020-12-08T09:29:38Z2020-12-08T09:29:38Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4141This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/41412020-12-08T09:29:38ZDevelopment of a microfluidic flow-focusing droplet generating device utilising rapid prototyping techniqueIn the recent decades, droplet-based microfluidics has emerged as a promising research area which covers various applications in a broad spectrum of fields such as chemical reactions, drug discovery, molecule synthesis and cell biology. This study proposes the implementation of a microfluidic droplet generating prototype using the popular flow-focusing geometry. The proposed system is fabricated based on a rapid prototyping technique, which significantly simplifies the fabrication process, reduces the production cost and shortens the time-to-market as compared with traditional techniques. The functionalities and characteristics of the prototype were carefully verified by simulations and practical experiments. The obtained results showed that the generation of droplets could be precisely controlled by adjusting the flow rate ratio between the dispersed phase and the continuous phase.Xuan Loc Phamxuanloc97ars@vnu.edu.vnQuang Loc Dolocdq@gmail.comQuoc Tuan Vutvu.tuan@gmail.comNhu Cuong Nguyencuongnn241@gmail.comThu Hang Nguyenhang021197@gmail.comThanh Hang Tranhangtt.uet@vnu.edu.vnNgoc An Nguyenngocan@vnu.edu.vnThanh Tung Buitungbt@vnu.edu.vnDuc Trinh Chutrinhcd@vnu.edu.vn2020-12-08T09:29:25Z2020-12-08T09:29:25Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4138This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/41382020-12-08T09:29:25ZElectrostatic modulation of a photonic crystal resonant filterWe demonstrate continuous and reversible spectral modulation of a photonic crystal cavity resonant mode using electrostatic force. The design and simulation of an H0 cavity were done using finite-element analysis methods. Fabrication of the sample device was done in a cleanroom using state-of-the-art nanotechnologies that are compatible with fabrication techniques for complementary metal-oxide semiconductors and microelectromechanical systems. Upon the change of the applied bias voltage, the resonant tuning effect is quantitatively demonstrated. Furthermore, the dynamic response of the transmission output intensity with respect to the oscillating applied voltage is demonstrated.Minh Hoang Nguyenhoang.photonics@gmail.comThanh Tung Buitungbt@vnu.edu.vn2020-12-08T09:28:55Z2020-12-08T09:29:17Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4139This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/41392020-12-08T09:28:55ZBiological living cell in-flow detection based on microfluidic chip and compact signal processing circuitDetection and enumeration of biological living cells in continuous fluidic flows play an essential role in many applications for early diagnosis and treatment of diseases. In this regard, this study highlighted the proposal of a biochip system for detecting and enumerating human lung carcinoma cell flow in the microfluidic channel. The principle of detection was based on the change of impedance between sensing electrodes integrated in the fluidic channel, due to the presence of a biological cell in the sensing region. A compact electronic module was built to sense the unbalanced impedance between the sensing microelectrodes. It consisted of an instrumentation amplifier stage to obtain the difference between the acquired signals, and a lock-in amplifier stage to demodulate the signals at the stimulating frequency as well as to reject noise at other frequencies. The performance of the proposed system was validated through experiments of A549 cells detection as they passed over the microfluidic channel. The experimental results indicated the occurrence of large spikes (up to approximately 180 mV) over the background signal according to the passage of a single A549 cell in the continuous flow. The proposed device is simple-to-operate, inexpensive, portable, and exhibits high sensitivity, which are suitable considerations for developing point-of-care applications.Loc Quang Dolocdq@hus.edu.vnThanh Tung Buitungbt@vnu.edu.vnBao Anh Hoanganhbh@vnu.edu.vnNhu Cuong Nguyencuongnn241@gmail.comThi Thuy Ha Trantttha@gmail.comChun-Ping JenChun-Ping@gmail.comDuc Trinh Chutrinhcd@vnu.edu.vn2020-12-08T09:28:41Z2020-12-08T09:28:41Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4136This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/41362020-12-08T09:28:41ZAn electrohydrodynamic gyroscopeA novel configuration of gyroscope using an electro-hydrodynamics flow circulating in a confined space
is developed. The configuration includes three corona discharge based actuators to generate ionic flows inside three separated sub-channels which are connected to the main chamber. Ionic flows are merged together while they move through a nozzle installed at the main chamber entrance. After the merging phase, the conflated flow is diverged to move back to sub-channels where each accelerates at the discharge actuator. A master ring is installed at the end of the nozzle to remove any residual charge of the conflated ion flow. The ion flow velocity is measured using several hotwires installed in the main chamber. Since the configuration does not require any vibrating components, the present device is robust,
cost-effective and consumes low power, hence, very potential in application of inertial sensing.Van Ngoc Tranvanngoc@gmail.comThanh Van Dauv.dau@griffith.edu.auCanh-Dung TranCanh-Dung.Tran@usq.edu.auXuan Thien Dinhthien@cfd.ritsumei.ac.jpThanh Hoa Phanp.hoa@gmail.comDuc Trinh Chutrinhcd@vnu.edu.vnThanh Tung Buitungbt@vnu.edu.vn2020-12-08T09:28:32Z2020-12-08T09:28:32Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4134This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/41342020-12-08T09:28:32ZA new structure of Tesla coupled nozzle in synthetic jet micro-pumpSynthetic jet pump is a potential technique to improve the pumping performance by introducing a smart structure which can enhance counter-rotating vortexes. Aligning with this approach, a new structure of valveless micro-pump is developed in this work. The mechanism of the present micro-pump is based on the combination of the nozzle and a tesla element to rectify the synthetic jet. The new structure of “ace of spades” nozzle, named Tesla coupled nozzle, creates series of vortexes at the orifice of the pump chamber that allows to attenuate the reversed flows while fluid is drawn through the pump. The present
micro-pump is simple but robust and can perform at rather low voltages.Canh-Dung TranCanh-Dung.Tran@usq.edu.auHong Phuc Phamphucph-fme@mail.hut.edu.vnTuan-Khoa Nguyenkhoa.nguyentuan@griffithuni.edu.auHoang-Phuong Phanphuong.phanhoang@griffithuni.edu.auToan Dinhtoan.dinh@griffithuni.edu.auThanh Viet Nguyenthanh.nguyenviet@griffithuni.edu.auThanh Tung Buitungbt@vnu.edu.vnDuc Trinh Chutrinhcd@vnu.edu.vnNam-Trung Nguyennam-trung.nguyenEmailgriffith.edu.auDzung Viet Daod.dao@griffith.edu.auThanh Van Dauv.dau@griffith.edu.au2020-12-08T09:28:16Z2020-12-08T09:28:16Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4132This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/41322020-12-08T09:28:16ZSimulation and Experimental Study of a Synthetic Jet Valveless PumpA valveless microfluidic pump using a Lead Zirconate Titanate (PZT) diaphragm-actuated synthetic jet is developed and fabricated. For this present design, a valveless pump structure is developed in which the pump chamber is sealed one side and connected to an emitting nozzle at another side. The design is simulated using the multi-physics approach and then successfully investigated with a prototype produced by a low-cost additive fabrication technique. The device’s parameters including
the liquid pumping characteristics and the size of PZT membrane are optimized based on its desired performance. The developed device can be applied over a wide range of applications from micro-mixing to fluidic controlling.Luan Le Vanluanlv@vnu.edu.vnThanh Tung Buitungbt@vnu.edu.vnNhu Cuong Nguyencuongnn241@gmail.comNgoc An Nguyenngocan@vnu.edu.vnThien Xuan Dinhthien@cfd.ritsumei.ac.jpBao Lam Danglam.dangbao@hust.edu.vnCanh-Dung TranCanh-Dung.Tran@usq.edu.auDuc Trinh Chutrinhcd@vnu.edu.vnThanh Van Dauv.dau@griffith.edu.au2020-12-08T09:28:03Z2020-12-08T09:28:03Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4133This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/41332020-12-08T09:28:03ZStudy on Design Optimization of a Symmetry Two-Axis Tilt Angle Capacitive SensorThis paper presents the design, optimization, fabrication and characterization of a symmetrical twoaxis tilt angle sensor. The sensor consists of a globe-calotte-shaped excitation electrode and two pairs of sensing electrodes of the same dimensions, positioned symmetrically on a 3D printed hollow sphere. The sphere is filled with oil and air, and then mounted on the surface of a printed circuit board (PCB) for mechanical packaging and measurement. Experimental results show that the sensor can measure the tilt angle in both the x- and y-axes with sensitivity of 124 mV/° and resolution of ±0.15° in the range from −35° to 35°. The characteristics of the sensor on the x- and y-axes are similar. The proposed sensor can be used in several applications.Dac Hai Nguyenhaind75@gmail.comThi Thuy Ha Trantttha@gmail.comQuoc Tuan Vuvqtuan0211@gmail.comVan Thai Lethailv@haui.edu.vnDuc Trinh Chutrinhcd@vnu.edu.vnThanh Tung Buitungbt@vnu.edu.vnNgoc An Nguyenngocan@vnu.edu.vn2020-12-08T09:27:55Z2020-12-08T09:27:55Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/4151This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/41512020-12-08T09:27:55ZStudy on Thermal Convective Gas Gyroscope Based on Corona Discharge Ion Wind and Coriolis EffectIn this paper, we report on a gas gyroscope whose working principle is based on elec-tro-hydrodynamic flow generated by applying high voltage corona discharge, Coriolis acceleration and thermoresistive effects of sensing elements. Firstly, ionized air flow is created by applying high voltage between pin-ring electrodes as discharge-reference electrodes. When the sensor rotates, the ion wind is deflected because of Coriolis effect and four symmetric hot wires are used to recognize the direction change of ion wind. The simulation result confirms the deflection of air flow due to Coriolis force and the asymmetric thermal distribution of hot wires. The experiment result shows that the angular rate can be detected with a sensitivity of 4.7 µV/o/s.Thu Hang Nguyenhang021197@gmail.comVan Ngoc Trantvngoc84@gmail.comNhu Cuong Nguyencuongnn241@gmail.comThanh Van Dauv.dau@griffith.edu.auNgoc An Nguyenngocan@vnu.edu.vnDuc Trinh Chutrinhcd@vnu.edu.vnThanh Tung Buitungbt@vnu.edu.vn2019-12-24T04:37:09Z2019-12-24T04:37:46Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/3811This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/38112019-12-24T04:37:09ZDesign and Fabrication of a Ku-band Low Noise Amplifier using FR-4 SubstrateThe Low Noise Amplifier (LNA) plays an important role in many communication systems, especially at the receiver’s front-ends. In modern RF designs, The LNA is usually fabricated on a microstrip printed circuit board (PCB) due to its simplicity and ability of integrating flexibly with other components in a receiving circuitry unit. At frequencies lower than 6 GHz, the most prevalent substrate material for a microstrip LNA is FR-4 while at higher frequencies of over 10 GHz, it is challenging to design the LNA using this material without causing considerable losses to the RF signal. There are many works related to design microstrip LNA at high frequencies, however, the dielectric substrates used in most of them were high-cost materials for low dielectric loss. This paper introduces an LNA topology using the common, low-cost FR-4 substrate which can be operated in Ku-band for applications such as small satellites’ receivers, with the expected noise figure of lower than 1 dB, gain of around 10 dB and the return loss of around -10 dB. The stepped impedance matching technique has been used for transmission line optimization. The simulated and measured results are presented.Phuong Linh Tatplinh@vnsc.org.vnBernard Journetbernard.journet@ens-cachan.frGia Duong Bachduongbg@vnu.edu.vn2019-12-12T09:45:43Z2019-12-12T09:47:13Zhttp://eprints.uet.vnu.edu.vn/eprints/id/eprint/3776This item is in the repository with the URL: http://eprints.uet.vnu.edu.vn/eprints/id/eprint/37762019-12-12T09:45:43ZA design of wideband high-power 3-dB quadrature coupler using defected ground structure for status data
transmitting systemThe paper presents a wideband 3-dB quadrature coupler designed for operation at 2 GHz. The presented coupler is based on a broadside-coupled suspended structure in combination with a proposed defected ground structure (DGS) allowing for high power, wide-band and improved harmonic suppression performance. The experimental results show 0.2 dB of insertion loss, return loss of better than 18 dB and isolation of better than 25 dB in
the frequency range from 1.74 to 2.67 GHz. The proposed coupler is able to be integrated in the status data transmitting system, which is suitable for vessel monitoring. The fundamental characteristics of the implemented coupler have been measured and verified.Dinh The Anh Nguyenndtanh@vnsc.org.vnDuc Long Hoanglonghd@vnu.edu.vnGia Duong Bachduongbg@vnu.edu.vnDragos Dancila