Hoạt động nghiên cứu

Tổng kết hội nghị quốc tế Điện – Điện tử lần 2 Đại học Tôn Đức Thắng 2011 (ISEE-TDT 2011)

Trong 14 năm xây dựng và phát triển, Trường đại học Tôn Đức Thắng có định hướng lâu dài là phát triển thành Trường đại học nghiên cứu bên cạnh chức năng đào tạo nguồn nhân lực. Để thực hiện mục tiêu đó, năm 2009, Khoa Điện - Điện tử đã tổ chức hội nghị Quốc tế Kỹ thuật Điện - Điện tử lần thứ nhất. Nhằm tiếp tục duy trì và phát huy thành công của hội nghị lần 1, được sự khuyến khích của Ban giám hiệu, ngày 25 tháng 06 năm 2011, Khoa Điện - Điện tử tiếp tục tổ chức hội nghị Quốc tế lần thứ 2 "The 2nd Internaltional Symposium Electrical - Electronics Engineering" ISEE-TDT-2011.

ISEE-TDT 2011 được tổ chức theo thông lệ của hội nghị quốc tế. Hội nghị đã thu hút được 53 nhà khoa học với 34 báo cáo từ các trường đại học và các công ty chuyên ngành, trong đó có các trường đại học trên thế giới như: Đại học Ruhr, Đại học Khoa học và Ứng dụng Karlsruhe (Cộng hòa liên bang Đức), Đại học Kyung Hee (Hàn Quốc) và Đại học Vestfold (Na Uy).
 

Nội dung của các báo cáo đa dạng, phong phú và được chia thành 3 phân ban: Kỹ thuật điện, Điện tử viễn thông, Điều khiển tự động - Cơ điện tử. Đặc biệt, hội nghị đã nêu bật tầm quan trọng, tiềm năng, định hướng và nhu cầu nguồn nhân lực cho sự phát triển năng lượng gió ở Việt Nam qua các báo cáo mới của các chuyên gia như: PGS. TS. Nguyễn Bội Khuê, Chủ tịch Hiệp hội năng lượng gió Bình Thuận, ThS. Nguyễn Hoàng Dũng, Trưởng phòng dự án lưới điện, Công ty cổ phần tư vấn xây dựng điện 3, TS. Matthias Baitsch, Đại học Việt Đức.

Một vài con số đáng chú ý của ISEE-TDT 2011

  • Tổng số báo cáo: 34
  • Số trường đại học trong nước tham gia hội nghị: 10
  • Số công ty trong nước tham gia hội nghị: 2
  • Số trường đại học ngoài nước tham gia hội nghị: 5

Hội nghị đã thành công tốt đẹp. Thông qua hội nghị, các giảng viên, chuyên gia và nhà khoa học có dịp trao đổi kiến thức, kinh nghiệm về những hướng nghiên cứu mới cũng như xu hướng phát triển của các công nghệ mới hiện nay.

Hẹn gặp lại các nhà nghiên cứu, các giáo sư, tiến sĩ, giảng viên, sinh viên...vào hội nghị quốc tế Điện - Điện tử lần 3.

Ban tổ chức

Một số hình ảnh tại hội nghị:

ThS. Trịnh Minh Huyền, Phó Hiệu Trưởng Trường ĐH Tôn Đức Thắng phát biểu chào mừng hội nghị

TS. Nguyễn Dáo, Trưởng ban tổ chức, phát biểu khai mạc hội nghị

Báo cáo của PGS. TS. Nguyễn Bội Khuê, Chủ tịch hiệp hội năng lượng gió Bình Thuận

Báo cáo của ThS. Nguyễn Hoàng Dũng, Công ty Cổ phần Tư Vấn Xây Dựng Điện 3

Báo cáo của TS. Matthias Baitsch, Đại học Việt Đức

Các giảng viên trẻ của Khoa Điện - Điện Tử tham dự hội nghị

Các đại biểu tích cực thảo luận, trao đổi ý kiến

Tóm tắt các báo cáo tại hội nghị (để nhận được nội dung đầy đủ của các bài báo, xin vui lòng liên hệ với Khoa Điện - Điện Tử, trường Đại Học Tôn Đức Thắng. Email: This email address is being protected from spambots. You need JavaScript enabled to view it.; điện thoại: (08)-(38405997)

 

 

 

1. An Effective Method for Solving Economic Load Dispatch Problems

 

Nguyen Trung Thang

 

Ton Duc Thang University

 

Abstract: The optimal generation dispatch problem with only one fuel option for each generating unit has been solved for many recent years. However, it is more realistic to represent the fuel cost function for each fossil fired plant as a segmented piece-wise quadratic functions. This is because of development of technology in thermal plants to reach maximum fuel save. Those units are faced with the difficulty of determining which the most economical fuel to burn is. This paper presents an approach to solve the unit commitment problem with multiple fuel options. An advantage of the method is to formulate Lagrange mathematical function easily based on the Lagrange multiplier theory. The proposed method is tested on one test system consisting of ten generating units with various load demands and compared to other methods. The simulation results show that the method is efficient for the optimal generation dispatch problem with multiple fuel options.

 

 

 

2. A New Method for the Design of High Voltage Overhead Transmission Lines and Development in Power Transmit System

 

Nguyen Quy

 

Ho Chi Minh City University of Technology

 

Abstract: The design of high voltage overhead transmission lines and development in power transmit system are very important with power system. They effect to investment value and operation in power system. Today, the design of high voltage overhead transmission lines is base on current density of economic mainly. This paper will present a new method for the design of high voltage overhead transmission lines and development in power transmit system by Newton - Raphson method. Results obtained from this study will support designers, operators when worked in power system. Moreover, this study also helps to the planning of power system more stable.

 

 

 

3. Transient Dynamic Performance Improvement for STATCOM Using LQR Controller

 

Do Bui Dinh Thien, Nguyen Hung and Ngo Cao Cuong

 

Ho Chi Minh City University of Technology

 

Abstract: In this paper, the mathematical modeling of STATCOM based on a voltage source converter is presented. It is considered as a multiple input and multiple output nonlinear system (MIMO). A linearization method can be used to solve the nonlinear dynamic problem of STATCOM at its operating point. An optimal linear quadratic regulator (LQR) controller is applied to improve the transient dynamic performance of STATCOM. The system stability is guaranteed by optimal control theory. The simulation results are shown to illustrate effectiveness of the proposed controller.

 

 

 

4. Structural Lifetime Prediction for Wind Energy Con-verters based on Health Monitoring and System Identification

 

S. Lachmann, M. Baitsch*, D. Hartmann and R. Höffer

 

Ruhr-University of Bochum

 

*Vietnamese-German University

 

Abstract: Wind energy is an energy source which has a tremendous growth rate all over the world. However, due to the large number of required wind energy plants, maintenance and failure prediction is a major concern. This contribution presents a monitoring based approach to this problem. A computer model of the wind energy converter is continuously adapted to the actual situation, which is determined on the basis of in-situ measurements.

 

 

 

5. Differential Evolution Algorithm for Optimal Power Flow and Economic Load Dispatch with Valve Point Effects

 

Quang Trong Hung, Ngo Cao Cuong, Le Dinh Luong

 

Ho Chi Minh City University of Technology

 

Abstract: In this paper, we present a Differential Evolution (DE) method and apply it to two problems of optimal power flow (OPF) and the economic load dispatch (ELD) with Valve-Point effects in Power Systems. In the first case, the standard IEEE 30-bus network is tested and its solution is compared to the ones solved by Particle Swarm Optimization (PSO), Genetic Algorithm (GA), Ant Colony Optimization (ACO) methods. For the second one, the NPSO is tested on 13-unit, 40-unit system and validated by comparing results with classical evolutionary programming (CEP), improved fast evolutionary programming (IFEP), improved particle swarm optimization (IPSO) and efficient particle swarm optimization (EPSO) methods. The numerical results are illustrated in many Figures and Tables. It has shown that the proposed method is better than the others in terms of total fuel costs, total loss and computational times.

 

 

 

6. Simulation of Lightning Transient Responses of Chebyshev Optimized Gounding Grid

 

Huynh Van Van

 

Ton Duc Thang University

 

Abstract: This paper presents the application of the Finite Element methods to calculating and modeling the lightning transient responses on grounding grid. The uniform, exponential optimized grids and Chebyshev polynomials grounding grids are used in this work. The tested results obtained on many different models of the conductor and grids have seen the effectiveness of the proposed method and the influence of conductor compression to the transient values when the lightning current into the grid at the different positions.

 

 

 

7. A New Family of High Boost Voltage Inverters

 

Minh-Khai Nguyen, Nguyen Truong Thinh1, and Nguyen Van Nho2

 

Nguyen Tat Thanh University

 

1Hochiminh City University of Technical Education

 

2Ho Chi Minh City University of Technology

 

Abstract: This paper presents a new family of high boost voltage inverters. The proposed inverter is based on the well-known quasi-Z-source inverter topology and adds only one inductor and three diodes. In comparison to the switched-inductor Z-source inverter, for the same input and output voltage, the proposed inverter provides: continuous input current, a common ground with the dc source, reduced the passive component count, reduced voltage stress on capacitors, lower shoot-through current, and lower current stress on inductors and diodes. In addition, the proposed inverter can suppress inrush current at startup, which might destroy the devices. The operating principles, analysis and simulation results were presented. The simulation results verified that the converter has high step-up inversion ability.

 

 

 

8. A New Solution for Optimization Design of High Voltage Substation Grounding Grid

 

Huynh Van Van

 

Ton Duc Thang University

 

Abstract: In this paper, we propose a new method for the optimal design of grounding grid based on the point distribution using Chebyshev polynomial in two-dimensional domain. To evaluate the effectiveness and applicability, the values of mesh and step voltages, and metal mass of grounding grid designed by the proposed method are compared with ones calculated by using the exponential method in [1], [7]. In particular, we present the automatic program for designing the optimal grounding grid, where the proposed method and IEEE Std.80-2000 is used.

 

 

 

9. Determining Start Generation for Hydrothermal Power Systems

 

Nguyen Trung Thang

 

Ton Duc Thang University

 

Abstract: The paper presents an effective method based on the Lagrange multiplier theory to solve optimal scheduling of hydrothermal power system. Optimal scheduling of hydrothermal power systems is a great important problem to electric utility systems, the main objective of the problem is to determine the generation for each plant during scheduling period of time such that the total system generation cost is minimum while satisfying the system constrains of the generating limits and available water. The problem of optimal economic operation of hydrothermal power systems with fixed head hydro plants is considered and has had many researches about this. Determining of water discharge at the first interval is performed in this paper and lead to a low number of iteration and short computation time for convergence. The proposed method is tested on one system consisting of one hydro and one thermal plant through two examples.

 

 

 

10. Improved MPPT Algorithms: Applying Current Short Circuit Method for Perturb and Observe Algorithm

 

Tran Dinh Cuong

 

Ton Duc Thang University

 

Abstract: Maximum Power Point Tracking (MPPT) of Photovoltaic (PV) arrays dates back to the early 1960s. This paper presents one basic method of MPPT: The Perturb and Observe (P&O) Algorithm. The first part of this paper intends to give an overview of (P&O) Algorithm. In the second part of the paper, an improvement for the P&O method is proposed by using current short circuit.

 

 

 

11. Intelligent Control for Heating Systems Using Regenerative Energy

 

Hans-Werner Dorschner

 

University of Applied Sciences Karlsruhe, Germany and Vietnamese German University Ho Chi Minh City, Vietnam

 

 

 

12. Optimal Reactive Power Dispatch Particle Swarm Optimization with Constriction Factor

 

Vo Ngoc Dieu and Nguyen Phuc Khai

 

Ho Chi Minh City University of Technology

 

Abstract: This paper proposes a simple particle swarm optimization with constriction factor (PSO-CF) method for solving optimal reactive power dispatch (ORPD) problem. The proposed PSO-CF is the conventional particle swarm optimization based on constriction factor which can deal with different objectives of the problem such as minimizing the real power losses, improving the voltage profile, and enhancing the voltage stability and properly handle various constraints for reactive power limits of generators and switchable capacitor banks, bus voltage limits, tap changer limits for transformers, and transmission line limits. The proposed method has been tested on the IEEE 30-bus and IEEE 118-bus systems and the obtained results are compared to those from other PSO variants and other methods in the literature. The result comparison has shown that the proposed method can obtain total power loss, voltage deviation or voltage stability index less than the others for the considered cases. Therefore, the proposed PSO-CF can be favorable solving the ORPD problem.

 

 

 

13. A Survey of Optimized Routing Protocols for Mobile Ad hoc Networks

 

Thy-Linh Nguyen

 

Ton Duc Thang University

 

Abstract: The Optimized Link State Routing (OLSR) protocol is an optimization of the classical link state algorithm, adapted to the requirements of a Mobile Ad hoc Network (MANET). Routing protocols over MANET are a critical issue where data is transmitted generally over multi-hop paths. Many proposals have been addressed to enhance the network performance, defined by end to end delay, throughput, and network energy efficiency. The key concept used in OLSR is that of multipoint relays (MPRs). This paper presents the performance differences of multipoint relays algorithms and checks if these considerations could affect the network performance of a protocol that ensures a good QoS in terms of minimum-hop count (OLSR), end-to-end delay (OEDR), and network energy efficiency (EE-OLSR).

 

 

 

14. Design and Implementation of a MIMO-SDM System on FPGA Harware

 

Tran Thi Thao Nguyen, Nguyen Viet Ha, Vo Khac Thanh, and Bui Huu Phu

 

University of Natural Sciences Hochiminh City

 

Abstract: Modern wireless communication standards as IEEE 802.11n (Wifi), 3GPP Long Term Evolution, WiMAX and HSPA+ refer to the use MIMO technology (multiple-input and multiple-output) on the systems which use multiple antennas at both the transmitter and receiver to improve communication performance. It is well-known that spatial division multiplexing (SDM) technique is the typical method to significantly increase the channel capacity by transmitting multiple data streams simultaneously. The main contribution of the paper is to simulate MIMO-SDM system on MATLAB and implement the base-band MIMO system on hardware exploiting FPGA-based DSP Development Kit and DSPBuilder® software from Altera®. The results can be used for training, and further research and development of MIMO-based communication systems.

 

 

 

15. An Approach to Solving the Problems to Optimize Boolean Network in Logic Synthesis FPGA using of Walsh Spectral Representation

 

Nguyen Huu Khanh Nhan and Nguyen Kieu Tam

 

Ton Duc Thang University

 

Abstract: Spectral methods constitute a useful tool in the analysis and synthesis of Boolean functions, especially in cases when other methods reduce to effective search procedures. There is renewed interest in the application of spectral methods in this area, which extends also to the closely connected concept of the autocorrelation function, for which spectral methods provide fast calculation algorithms. This paper discusses the problem of logic synthesis algorithm to optimize the number of Boolean network nodes using the Walsh transform.

 

 

 

16. A Study on Cooperative MIMO Systems

 

Vo Khac Thanh, Nguyen Minh Tri, and Bui Huu Phu

 

University of Natural Science Hochiminh City

 

Abstract: MIMO (Multiple-Input Multiple-Output) technology has considered a technology for high speed broadband transmission systems. Recently, Cooperative MIMO has been a hot research topic, which applies the advantages of MIMO systems. In the paper, we present an overview of Cooperative MIMO systems, then two signal processing techniques, Amply & Forward and Decode & Forward, are studied well. Simulations evaluated the quality of the cooperative communication systems.

 

 

 

17. DSP-based Tx and Rx Model Employing FPGA for OFDM Optical Communication System

 

Dang Le Khoa1, Nguyen Huu Phuong1, Le Nguyen Binh1, Dang Van Liet2

 

1University of Natural Sciences Hochiminh City

 

2European Research Center, Germany

 

Abstract: This paper presents an implementation of an OFDM transmitter (Tx) and receiver (Rx) for generation of orthogonal signals in the electrical digital signal processing (DSP) domain for modulation of optical modulators and the detection of such signals after detected by optical receivers then recovering of orthogonal signals. The DSP-based system employs both MALAB Simulink and FPGA-based development software and hardware platforms. Simulink and hardware models presented are scalable to higher speed allowing possible implementation in multi-Giga samples per second electronic processors for advanced optical communications.

 

 

 

18. A SVD Analysis for Channel Matrix in MIMO Systems

 

Dinh-Thuan Do

 

Ton Duc Thang University

 

Abstract: A new channel estimation approach based Singular Value Decomposition (SVD) for multiple input multiple output (MIMO) system is analyzed. The main idea of our technique is, using specific properties of the SVD computation in optimized method using the second order statistic (SOS) function. Because we still use the training-based least square (LS) for a part of the channel matrix and hence, our scheme can be described as the semi-blind algorithm which has strongly attracted more and more researchers in the wireless field. Our detailed analysis validates the performance and computational advantages of the proposed method. Especially, in this paper we apply in this paper such technique for MIMO using orthogonal space time code (OSTBC). Simulation results confirm our modified scheme and illustrate that the new semi-blind channel estimation is capable of improving the quality of the overall system.

 

 

 

19. Hybrid Scheme for PAPR Reduction in WiMAX

 

Dinh-Thuan Do

 

Ton Duc Thang University

 

Abstract: Fourth generation (4G) wireless technology are expected to be based on worldwide interoperability for microwave access (WiMAX) systems. However, high peak to average power ratio (PAPR), a main drawback in mobile WiMAX using orthogonal frequency division multiplexing (OFDM), are solved in some solutions for many years. Especially, such wireless systems with large number of sub-carriers lead to undesired problems for practical applications. In this investigation, we present the PAPR reduction performance with two different PAPR reduction schemes: partial transmit sequence (PTS) and selective mapping (SLM). These methods are analyzed in terms of complementary cumulative distribution function (CCDF) under different models. Simulations results show that the proposed schemes reduce the PAPR of the transmit signals considerably.

 

 

 

20. MMSE based Channel Estimation Technique in MIMO OSTBC Systems

 

Dinh-Thuan Do

 

Ton Duc Thang University

 

Abstract: In this paper, we investigate the key role of the channel estimation algorithm using in Multi-Input Multi-Output (MIMO) communications. This technique, as the best candidate in real implementations, is applied on training based channel estimation for performance improvement. Experimental results indicate that the Minimum Mean Squares Estimation (MMSE) based channel estimation method not only alleviates the performance of MIMO channel estimation but also significantly reduces the complexity caused by matrix computation. Simulation results show that the Bit Error Rate (BER) performance in some scenarios of the MIMO systems.

 

 

 

21. Real Time Results of an Active Noise Controller

 

Huynh Van Tuan1 and Duong Hoai Nghia2

 

1University of Natural Science Hochiminh City

 

2Ho Chi Minh City University of Technology

 

Abstract: Active noise control (ANC) is a popular research topic for almost three decades [1, 2]. The basic principle of ANC is to introduce an "antinoise" signal that has the same amplitude but with opposite phase as the primary noise such that the resulting noise is attenuated in the region where the noise is to be controlled. In this paper we present new theoretical and experimental results for adaptive filter ANC system. A new technique for feedback active noise control is proposed. An on line dynamic learning algorithm based on the error gradient descent method is carried out. Simulation results and real time results demonstrates the effectiveness of the proposed ANC system.

 

 

 

22. Receiver Based Multi-channel MAC Protocol for Ad hoc Network

 

Dang Ngoc Minh Duc1 and Dang Ngoc Hanh2

 

1Kyung Hee University, Korea

 

2Vestfold University College, Norway

 

Abstract: The medium access control (MAC) protocol is designed only for single channel in the IEEE 802.11 standard. That means the throughput of the network is limited by the bandwidth of the channel. The multi-channel can be exploited to get more concurrent transmission. However, the single channel MAC protocol does not work well in a multi-channel environment because of the multi-channel hidden terminal problem. In this paper, we propose a new scheme of Multi-channel MAC protocol named Receiver Based MMAC (RB-MMAC) that can avoid the multi-channel hidden terminal problem as well as improve the performance of the network. The simulation results show that the proposed protocol achieves a higher throughput than other schemes.

 

 

 

23. Controlling a Magnetic Levitation Model using a Feedforward Neural Network - Sliding Mode Control

 

Vo Huu Hau

 

Ton Duc Thang University

 

Abstract: Sliding mode control (SMC) is able to cancel uncertainty of nonlinear system. However, the discontinuous control signal causes chattering. Besides, mathematical model of the plant is difficult to know. In this paper, a feedforward neural network (FNN) is combined with SMC. The weights of network are updated using a backpropagation algorithm. Simulations are carried out on a magnetic levitation model.

 

 

 

24. The Application of Fuzzy PID Control Method Combine with FOC to Speed Control of Induction Motor

 

Nguyen Van Hieu1, Pham Van Luc2 and Nguyen Thanh Phuong

 

Ho Chi Minh University of Technology (HUTECH)

 

1A41 Manufactory, Viet Nam

 

2Vinh Long Community College (VLCC)

 

Abstract: Field Oriented Control (FOC), provides independent control of torque and flux method is being used popularly to control induction motor response improving. In this paper, a Hybrid Fuzzy PID controller combine with FOC to speed control of induction motor are presented. The algorithm has verified through simulation result.

 

 

 

25. Rehabilitation Device for Paralyzed Children

 

Thieu Quang Tri

 

Ton Duc Thang University

 

Abstract: To help children who suffer from palsy learn how to walk, this research was conducted. In this research, a leg-exoskeleton which is actuated by a hydraulic system was developed. This device has three degrees of freedom at each leg (at the hip, knee and ankle). In the hydraulic system, six directional solenoid valves and twelve flow control valves are used in order to control the movement and the speed of the leg-exoskeleton. An AT89C52 microprocessor is used for monitoring the positions of all the joints and controlling the solenoid valves. By splitting the walking process into phases and adjust the flow control valves, the leg-exoskeleton can perform a walking motion. With this motion, this device can guild the patient's legs and help them learn how to walk.

 

 

 

26. Indirect Adaptive Sliding Mode Control using RBF Neural Network

 

Dong Si Thien Chau1 and Duong Hoai Nghia2

 

1Ton Duc Thang University

 

2Hochiminh City University of Technology

 

Abstract: This paper describes an indirect adaptive sliding mode control. The models of the system are identifed on - line based on RBF neural network. The stability of the control system is analysed using Lyapunov's theory. Simulation results are given to illustrate the proposed control system.

 

 

 

27. Designing a Differential Sliding Mode Controller for Wheeled Mobile Robot with Disturbances

 

Nguyen Hung, Trieu Van Tam1 and Vo Hoang Duy2

 

Hochiminh City University of Technology (HUTECH)

 

1University of Technical Education

 

2Ton Duc Thang University

 

Abstract: In this paper, a control scheme that makes the combination of a kinematic controller and a sliding mode dynamic controller with external disturbances is proposed for an mobile robot to track a desired trajectory with a specified constant velocity. It provides a method of taking into account the specific mobile robot dynamics to convert desired velocity control inputs into torques for the actual mobile robot. First, feedback velocity control inputs are designed for the kinematic controller to make the tracking error vector asymptotically stable. Then, a sliding mode dynamic controller is designed such that the mobile robot's velocities converge to the velocity control inputs. The control laws are obtained based on backstepping technique. The system stability is proved using the Lyapunov stability theory. The simulation results are presented to illustrate effectiveness of the proposed controller.

 

 

 

28. Building an Adaptive Controller based on Lyapunov Techniques for Wheeled Mobile Robot Tracking Trajectory

 

Le Anh Tuan

 

Ton Duc Thang University

 

Abstract: In this paper, an adaptive controller is proposed for a differentially driven wheeled mobile robot tracking planned trajectories under disturbances. The control scheme consists of two parts, a kinematic control loop to generate the right and left wheel angular velocities required to move the robot tracking the desired trajectory, and a dynamic control loop to compute the control torques driving the wheels following the demanded angular velocities. The dynamic controller consists of a proportional control term to compensate the wheel velocity errors, and an adaptive control term to face with uncertainties. The controller is designed thanks to Lyapunov stability theory. Simulation results showed that the robot is able to track a predefined trajectory well although affected by factors of uncertainties such as unexpected changed load, surface friction or unknown external disturbances while moving.

 

 

 

29. Lyapunov Redesign - Feedback Linearization for a Pendulum System

 

Vo Huu Hau

 

Ton Duc Thang University

 

Abstract: Pendulum System is a common model in control theory. In this paper, feedback linearization (FL) is used to control a model of pendulum system. Simulation results show that FL cancels system's nonlinearities well but it is very sensitive with uncertainty of system's parameters. Lyapunov Redesign (LR) technique are combined with FL for stabilization as presence of uncertainty.

 

 

 

30. Manufacturing Technology LPG Cylinders by Composites Materials

 

Ngo Thanh Hai1 and Vũ Thị Hồng Nga2

 

1Ton Duc Thang University

 

2Hochiminh city University of Industry

 

Abstract: LPG is a fuel sources being used very popular in worldwide. Production of LPG tanks (or LPG cylinders) has become an industry developed rapidly with the increasing demand in both quantity and quality. This paper introduces a new advanced technology to manufacture pressure tanks for containing LPG combined the progress of automation and material technology.

 

 

 

31. On-line Training Solution to Modify the Inverse Kinematic Approximation of a Robot Manipulator

 

Dong Si Thien Chau and Dinh Hoang Bach

 

Ton Duc Thang University

 

Abstract: This paper describes a new practical approach for approximating the inverse kinematics of a manipulator using an RBFN (Radial Basis Function Network). In fact, there are several traditional methods based on the known geometry of the manipulator to calculate the relationship between the joint variable space and the world coordinate space. However, these traditional methods are impractical if the manipulator geometry cannot be easily determined, in a robot-vision system for example. Therefore, a neural network with its inherent learning ability can be an effective alternative solution for the inverse kinematics problem. However, sometimes a well-trained network cannot work effectively in the operational phase because the initial network training occurs in an environment that is not exactly the same as the environment where the system is actually deployed. In this paper, an online retraining solution using the Delta rule is presented for systems whose characteristics change due to environmental variations. Moreover, a "free interference rule" is also suggested to avoid learning interference where the training effect of a current training point may upset some of the weights which were trained with previous points. The simulation results prove that the proposed approach is effective.

 

 

 

32. Rudder-Roll Damping Control for Ships Using Adaptive Neural Networks

 

Phung Hung Nguyen, Duy Anh Nguyen, Ngoc Bich Le and Tan Tien Nguyen

 

Hochiminh City University of Technology

 

Abstract: This paper presents a new application of adaptive neural network to designing Rudder-Roll Damping (RRD) control system for ships. Firstly, the neural network controller which will be applied is presented. Secondly, a RRD control system using this neural network approach is developed. It uses two neural network controllers for heading control and roll damping control separately. Finally, we carry out computer simulation of this RRD control system to compare with a linear quadratic optimal RRD control system; discussions and conclusions are provided. The simulation results show the feasibility of the proposed neural network control approach in designing RRD control system for ships.

 

 

 

33. Sliding Mode Control for Discrete Nonlinear System

 

Dong Si Thien Chau

 

Ton Duc Thang University

 

Abstract: In this paper, sliding mode control for discrete nonlinear system is presented. The control signal ensures the requirement of necessary and sufficient reaching conditions of sliding mode control. The simulation resutls show the proposed controller is stability, convergency and robustness.

 

 

 

34. Diffuser Elements Design Optimization for Performance Improvement of Diffuser-Typed Polymethylmethacrylate Peristaltic Micropumps

 

Ngoc-Bich Le1, Duy Anh Nguyen1 and Vo Hoang Duy2

 

Hochiminh City University of Technology

 

2Ton Duc Thang University

 

Abstract: Utilizing micro-electro-mechanical-systems (MEMS) techniques and a solvent-assisted bonding process, a new generation of diffuser peristaltic polymethylmethacrylate (PMMA) micropumps was optimized and fabricated. The main purpose of this study is to compare the performance of optimized and un-optimized micopump which have the same diffuser throat/inlet area (i.e. 160000 μm2). Furthermore, an additional optimized design which has smaller diffuser inlet area was considered to validate and analyze the effect of diffuser inlet area to the micropump performance. The experimental results were validated by comparing with previous generation which had not been optimized the diffuser element. Specifically, the experimental results showed that, with similar diffuser element inlet area (i.e. 160000 μm2), with and without optimized micropumps yield maximum flow rates of 246.4 μL/min and 194.8 μL/min, respectively. Furthermore, it is shown that the back pressure in the optimized micropump is 6.9 kPa, while that in the un-optimized pump is 5.69 kPa. The effect of diffuser element throat/inlet area to pump flow rate and back pressure was investigated by comparing the experimental results of two optimized designs, one with 80 µm × 80 µm and the other with 127 µm × 127 µm cross-sectional area. The results indicated that, the design with larger inlet area gave higher flow rate. However, the rate of reduction in the maximum flow rate with increasing back-pressure increases at the higher inlet area design, which is due to the greater pressure dissipation/loss associated with a larger channel cross-sectional area.