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Asia Simulation Conference 2007, AsiaSim 2007

作者： Hu, Xinrong Wei, Lan Li, Dehua Dept. of Computer Science and Technology WuHan University of Science and Engineering WuHan 430074 China Institute for Pattern Recognition and Artificial Intelligence State Education Commission Laboratory for Image Processing and Intelligence Control HuaZhong Univ. of Science and Technology WuHan 430074 China

ISBN: (纸本)9783540775997

A satisfied deformable object simulation should be general, accurate, efficient and stable. Explicit, implicit and semi-implicit numerical integration methods have contributed to large performance enhancements in the field of deformable simulation. Cloth is the most representative deformable object. In this paper, we propose an improved embedded Runge-Kutta integration method to solve the deformable simulation that based on classical spring-mass model. Traditional embedded Runge-Kutta methods generally solve ordinary differential equations of deformable object simulation. Most of them tend to concentrate on the efficiency of the simulation process, and not the fidelity of the simulation result. We investigate and determine the extent to which the overall quality must be compromised in order for the stable conditions to be satisfied. The improved Runge-Kutta method proposed in our paper incorporates the fixed time step and adaptive time step in solving cloth motion equations to achieve a controllable error evaluation. Compared with the other Runge-Kutta methods, the proposed method has some advantages for cloth simulation: controllable error evaluation without extra computations, excellent efficiency, good stability and satisfied precision. Experiment demonstrates that this method results in simulation efficiency improvements and is considerable practicable. © Springer-Verlag Berlin Heidelberg 2007.

关键词： Animation

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Biochemical mathematical modeling with Modelica and the BioChem library 6

Biochemical mathematical modeling with Modelica and the BioC...

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6th International Conference APLIMAT 2007

作者： Fritzson, Peter Ulfhielm, Erik Belic, Ales Fransson, Martin Grèen, Henrik PELAB - Programming Environment Lab. Dept. of Computer and Information Science Linköpings Universitet LinköpingSE-581 83 Sweden Laboratory for Modeling Simulation and Control Faculty of Electrical Engineering University of Ljubljana LjubljanaSI-1000 Slovenia Clinical Pharmacology Dept. of Medicine and Care Linköpings Universitet LinköpingSE-581 85 Sweden

ISBN: (纸本)9788096956265

Considering the large amounts of data that is nowadays produced in the biochemistry (functional genomics) it is difficult to extract the information from the measurements. There is currently also a great interest in the development of novel analytical technologies for rapid screening of disease symptoms in pharmaceutical and clinical applications. Modeling and simulation can provide a useful help in understanding the relations of the measured substances and to minimize the need for measurements. The BioChem library presented here is the first free Modelica library available for mathematical modeling of biochemical processes. Three examples are shown to illustrate the library. First, a simple insulin model is presented. Then a simplified model of cholesterol together with simulations are shown. Next, a simple drug model together with parameter estimation in NONMEN are presented. The BioChem library allows for fast and end-user friendly modeling of biomedical systems. The graphical user interface provides graphics similar to that used in the description of metabolic pathways in biochemistry.

关键词： Cholesterol

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engineering procedure for analysis of nonlinear structure consisting of fuzzy element and typical nonlinear element

Engineering procedure for analysis of nonlinear structure co...

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Mediterranean Conference on control and Automation (MED)

作者： Tomislav Sijak Ognjen Kuljaca Ljubomir Kuljaca Brodarski Institute/Control Engineering Dept Zagreb Croatia Alcorn State University/Systems Research Institute Alcorn State USA Faculty of El. Eng. and Computing/Dept. of Control and Computer Zagreb Croatia

engineering procedure for approximate analytical determination of describing function of nonlinear systems with odd static characteristics is presented in the paper. Generalized mathematical expressions for determining such describing function with error estimation are given. The procedure is illustrated on determination of describing function, and corresponding error estimation, of nonlinear structure consisting of fuzzy element and typical nonlinear element.

关键词： Fuzzy control Power harmonic filters Fuzzy systems Nonlinear systems control systems Nonlinear control systems Error analysis Frequency control engineering Signal synthesis

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A digital signal processing approach for modulation quality assessment in WiMAX systems

A digital signal processing approach for modulation quality ...

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IEEE Instrumentation and Measurement Technology Conference

作者： Leopoldo Angrisani Massimo D'Apuzzo Mauro D'Arco Dept. of Computer Science and Control Systems Università degli Studi di Napoli Federico II Napoli Italy Dept. of Electrical Engineering Università degli Studi di Napoli Federico II Napoli Italy

Modulation quality in WiMAX systems that rely on OFDM modulation is dealt with. A digital signal processing approach is, in particular, proposed, aimed at assessing the performance of transmitters in terms of standard parameters. At present, WiMAX technology deployment is at the very beginning. Also, measurement instrumentation mandated to assist WiMAX apparatuses production and installation is not completely mature, and entitled to be significantly improved in terms of functionality and performance. In particular, no dedicated instrument is already present on the market, but the available solutions are arranged complementing existing hardware, such as real-time spectrum analyzers and vector signal analyzers, with a proper analysis software. Differently from the aforementioned solutions, the proposed approach is independent of the specific hardware platform mandated to the demodulation of the incoming WiMAX signal. It can operate, in fact, with any hardware capable of achieving and delivering the baseband I and Q components of the signal under analysis. Moreover, being open-source it can be improved or upgraded according to future needs.

关键词： Digital signal processing Digital modulation Quality assessment WiMAX OFDM modulation Hardware Independent component analysis Signal analysis Instruments Transmitters

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LANDING AN UNMANNED AIR VEHICLE: VISION BASED MOTION ESTIMATION AND NONLINEAR control

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Asian Journal of control 2008年第3期1卷

作者： Omid Shakernia Yi Ma T. John Koo Shankar Sastry Dept. of Electrical Engineering & Computer Science University of California at Berkeley Berkeley CA94720-1774 U.S.A. Tak-Kuen John Koo received the B.Eng. degree in 1992 in Electronic Engineering and the M.Phil. in 1994 in Information Engineering both from the Chinese University of Hong Kong. From 1994 to 1995 he was a graduate student in Signal and Image Processing Institute at the University of Southern California. He is currently a Ph.D. Candidate in Electrical Engineering and Computer Sciences at the University of California at Berkeley. His research interests include nonlinear control theory hybrid systems inertial navigation systems with applications to unmanned aerial vehicles. He received the Distinguished M.Phil. Thesis Award of the Faculty of Engineering The Chinese University of Hong Kong in 1994. He was a consultant of SRI International in 1998. Currently he is the team leader of the Berkeley AeRobot Team and a delegate of The Graduate Assembly University of California at Berkeley. He is a student member of IEEE and SIAM. S. Shankar Sastry received his Ph.D. degree in 1981 from the University of California Berkeley. He was on the faculty of MIT from 1980-82 and Harvard University as a Gordon McKay professor in 1994. He is currently a Professor of Electrical Engineering and Computer Sciences and Bioengineering and Director of the Electronics Research Laboratory at Berkeley. He has held visiting appointments at the Australian National University Canberra the University of Rome Scuola Normale and University of Pisa the CNRS laboratory LAAS in Toulouse (poste rouge) and as a Vinton Hayes Visiting fellow at the Center for Intelligent Control Systems at MIT. His areas of research are nonlinear and adaptive control robotic telesurgery control of hybrid systems and biological motor control. He is a coauthor (with M. Bodson) of “Adaptive Control: Stability Convergence and Robustness Prentice Hall 1989.” and (with R. Murray and Z. Li) of “A Mathematical Introduction to Robotic Manipulati

In this paper, we use computer vision as a feedback sensor in a control loop for landing an unmanned air vehicle (UAV) on a landing pad. The vision problem we address here is then a special case of the classic ego-motion estimation problem since all feature points lie on a planar surface (the landing pad). We study together the discrete and differential versions of the ego-motion estimation, in order to obtain both position and velocity of the UAV relative to the landing pad. After briefly reviewing existing algorithm for the discrete case, we present, in a unified geometric framework, a new estimation scheme for solving the differential case. We further show how the obtained algorithms enable the vision sensor to be placed in the feedback loop as a state observer for landing control. These algorithms are linear, numerically robust, and computationally inexpensive hence suitable for real-time implementation. We present a thorough performance evaluation of the motion estimation algorithms under varying levels of image measurement noise, altitudes of the camera above the landing pad, and different camera motions relative to the landing pad. A landing controller is then designed for a full dynamic model of the UAV. Using geometric nonlinear control theory, the dynamics of the UAV are decoupled into an inner system and outer system. The proposed control scheme is then based on the differential flatness of the outer system. For the overall closed-loop system, conditions are provided under which exponential stability can be guaranteed. In the closed-loop system, the controller is tightly coupled with the vision based state estimation and the only auxiliary sensor are accelerometers for measuring acceleration of the UAV. Finally, we show through simulation results that the designed vision-in-the-loop controller generates stable landing maneuvers even for large levels of image measurement noise. Experiments on a real UAV will be presented in future work.

关键词： Motion estimation computer vision based control unmanned air vehicle differential flatness

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PARALLEL AND DISTRIBUTED SIMULATION OF FRAME RELAY NETWORKS

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IFAC Proceedings Volumes 2007年第9期40卷 304-309页

作者： Andrzej Sikora Ewa Niewiadomska-Szynkiewicz Dept. of Control and Computation Engineering Warsaw University of Technology ul. Nowowiejska 15/19 00-665 Warsaw Poland Research and Academic Computer Network (NASK) ul. Wαwozowa 18 02-796 Warsaw Poland

This paper deals with the description of a software framework FR/ASimJava for large scale Frame Relay networks simulation and its application to the exampled networks simulation. FR/ASimJava is implemented based on ASimJava – a Java-based software package that can be used to develop parallel and distributed simulators of complex real-life systems. The focus is on scalability and efficiency of large scale networks simulation. We describe the functionality, design and performance of FR/ASimJava software. The case studies – simulations of six networks operating under Frame Relay are provided to illustrate the effectiveness of the presented software tool.

关键词： computer simulation communication protocols distributed simulation simulators software performance synchronization

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Meta-search utilizing evolutionary recommendation: A web search architecture proposal

Meta-search utilizing evolutionary recommendation: A web sea...

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1st International Workshop on Intelligent Web Based Tools, IWBT 2007 - In Conjunction with the 19th IEEE International conference on Tools with Artificial Intelligence, ICTAI 2007

作者： Húsek, Dušan Keyhanipour, Amir Moshiri, Behzad Owais, Suhail S.J. Snášel, Václav Krömer, Pavel Platoš, Jan Institute of Computer Science Academy of Sciences of the Czech Republic CZ182O7 Prague Czech Republic Control and Intelligent Processing Center of Excellence School of Electrical and Computer Engineering University of Tehran Iran Information Technology Al-Balqa' Applied University Ajloun University College P.O. Bo 6 JO 2681O Ajloun Jordan FEECS Dept. of Computer Science VŠB Technical University of Ostrava 17. listopadu 15 CZ 708 33 Ostrava-Poruba Czech Republic

An innovative meta-search engine named WebFusion has been presented. The search system learns the expertness of every particular underlying search engine in a certain category based on the users' preferences according to an analysis of click-through behavior. In addition, an intelligent re-ranking method based on ordered weighted averaging (OWA) was introduced. The re-ranking method was used to fuse the results' scores of the underlying search engines. Independently, a progressive application of evolutionary computing to optimize Boolean search queries in crisp and fuzzy information retrieval systems was investigated, evaluated in laboratory environment and presented. In this paper we propose an incorporation of these two innovative recent methods founding an advanced Internet search application.

关键词： Search engines

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Implementation of Fuzzy Logic controller with Bifurcation control of a Current-mode Boost Converter

Implementation of Fuzzy Logic Controller with Bifurcation Co...

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2007 International Conference on Power Electronics and Drive Systems (PEDS 2007), vol,4

作者： Noppadol Khaehintung Phaophak Sirisuk Anantawat Kunakorn Department of Control and Instrumentation Engineering Thailand Dept. of Control and Instrumentation Engineering Mahanakorn University of Technology Bangkok Thailand Dept. of Computer Engineering Mahanakorn University of Technology Bangkok Thailand Dept. of Electrical Engineering King Mongkut's Institute of Technology Ladkrabang Bangkok Thailand

This paper presents the design of a basic fuzzy logic controller for switching current-mode DC/DC boost converters. The proposed simple fuzzy logic controllers used only nine rules to regulate output voltage. Moreover, they provide an optimal slope compensation to keep the system adequately remote from the first bifurcation point by means of stabilizing around the reference signal. In spite of nonlinear characteristics and instabilities of the converter, the performance of the closed-loop control system can be considerably improved to avoid bifurcation phenomena. The experimental results found that these techniques introduced in this paper give satisfactory results with the regulating and tracking modes under changes in operating conditions.

关键词： Current-mode Boost Converter Fuzzy Logic controller Bifurcation control Slope Compensation

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Approach Lighting System Lightning Mitigation and Individual control Cabinet Protection

Approach Lighting System Lightning Mitigation and Individual...

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Annual North-American Power Symposium

作者： James A. Momoh Nadir Wade Arunsi Chuku Lateef L. Baruwa Center for Energy Systems and Control CESaC Howard University College of Medicine Washington D.C. DC USA Center for Energy Systems and Control (CESaC) Howard University Washington DC USA Center for Energy Systems and Control CESaC Department of Electrical and Computer Engineering ECE Howard University College of Medicine USA Dept. of Electrical and Computer Engineering (ECE) Howard University. Air Traffic Systems Division Federal Aviation Administration (FAA) Washington DC USA

The mitigation of the impact of lightning and the individual control cabinet (ICC) protection of an approach lighting system (ALS) against over-voltage is the focus of this paper. It is the objective of this paper to evaluate three proposed ALS topologies and select the grounding configuration which optimally mitigates the high voltage and current levels caused by lightning, as well as to assess the over-voltage reduction capability of a metal-oxide varistor and its ability to provide protection to the individual control cabinet to prevent damage. Simulation of the grounding system of each ALS topology using a sensitivity study, which incorporates changes in conductor and environmental characteristics, is performed to determine the robustness of each ALS topology. Performance of a hands-on destructive test is also carried out to obtain practical results to compare with simulation results. This paper provides the foundation for improving the current ALS grounding and protective measures by updating standards and specifications to promote increased reliability and safety, as well as reduced equipment cost.

关键词： Lightning Lighting control control systems Protection Topology Grounding Varistors Optimal control Voltage control Conductors

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Design and Simulation of Ultrasonic Linear Motor using Multilayer Ceramic Actuator

Design and Simulation of Ultrasonic Linear Motor using Multi...

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IEEE International Symposium on Applications of Ferroelectrics (ISAF)

作者： Juhyun Yoo Sangho Lee Jaeil Hong Hyunsun Song Durkwon Park Eunsang Hwang Department of Electrical Engineering Semyung University Chungbuk South Korea Department of Computer Science Semyung University Chungbuk South Korea Dept. of Electrical Information Control Dongseoul College Seongnam Gyeonggi 461-714 Korea Semyung University Department of Computer Science Jechon Chungbuk 390-711 Korea

In comparison with conventional electromagnetic motors, ultrasonic motors have many advantages such as a large torque at the low velocity, good controllability, rapid response, quiet operation, simple structure and non electromagnetic field induction, etc. These features have led to the development of various ultrasonic motors in many industrial fields. Hence, in this study, ultrasonic linear motor using multilayer structured ceramic actuator was designed and simulated using ANSYS of finite element method(FEM) simulator for investigating the optimum conditions of it. The ultrasonic linear motor studied in this paper was designed using the 1st longitudinal (L 1 ) and 4th bending (B 4 ) vibration. The size of ceramic actuator is 15 mm long and 5 mm wide. And one-layer thickness of actuator is 60 mu m. The dimension of linear motor is 61 times 5 times 3 mm. The sectional size of projection is 1.5 times 5 mm. The driving voltage of the motor was very low as 5 Vrms. With the increase of the number of piezoelectric ceramic layers, displacement of node was increased up to 21 layered ceramic actuator and then decreased. Maximum z displacement of node was about 7.02 mum at the 21 layered ultrasonic motor.

关键词： Nonhomogeneous media Ceramics Hydraulic actuators Electromagnetic fields Induction motors Electromagnetic induction controllability Finite element methods Voltage Piezoelectric actuators

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