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2007 Mediterranean Conference on control and Automation, MED

作者： Rabi, Maben Baras, John S. Automatic Control Laboratory School of Electrical Engineering Royal Institute of Technology Stockholm 100 44 Sweden Institute for Systems Research Department of Electrical and Computer Engineering University of Maryland College Park MD 20742 United States

ISBN: (纸本)142441282X

In networked control systems, because of limits on communication rates, control waveforms are frequently piece-wise constant with limits on rates at which they can switch levels. It is, therefore, natural to expect event-triggered control switchings to perform more efficiently than time-triggered ones. This article verifies the validity of this supposition. A method for designing good level-triggered control schemes is obtained by reducing the continuous time problem to one in discrete time. Then, by numerical procedures, the performance of the level-triggered scheme is computed for comparison with that of the periodically switched control scheme. © 2007 IEEE.

关键词： Networked control systems

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Calculation of core loss using the Jiles-Atherton model incorporated into magnetic field analysis

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Archives of Electrical engineering 2007年第219-1期56卷 57-69页

作者： Jagiela, Mariusz Institute of Electromechanical Systems and Industrial Electronics Faculty of Electrical Engineering Automatic Control and Computer Science Opole University of Technology

The paper deals with the calculation of hysteresis power loss in cores of electromechanical converters. The analysis was carried out using the Jiles-Atherton model of ferromagnetic hysteresis incorporated into two-dimensional time-stepping finite element model. A vector hysteresis model was constructed by the vectorisation of a scalar model. The total power loss due to hysteresis was split into two component, one originating from the purely alternating magnetic field, and the second being a consequence of the local predomination of vector nature of magnetic field distribution. Two computational examples are presented showing the general applicability of the algorithm for determination of power loss distribution.

关键词： Electric losses

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On the design and control of wireless networked embedded systems

On the design and control of wireless networked embedded sys...

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Joint 2006 IEEE Conference on control Applications (CCA), computer-Aided control Systems Design Symposium (CACSD) and International Symposium on Intelligent control (ISIC)

作者： Årzén, Karl-Erik Bicchi, Antonio Hailes, Stephen Johansson, Karl H. Lygeros, John Department of Automatic Control Lund University Sweden Centro E. Piaggio University of Pisa Italy Department of Computer Science University College London United Kingdom School of Electrical Engineering Royal Institute of Technology Stockholm Sweden Department of Electrical and Computer Engineering University of Patras Greece

ISBN: (纸本)0780397975

Wireless networked embedded systems are becoming increasingly important in a wide area of technical fields. In this tutorial paper we present recent results on the design of these systems and their use in control applications, that have been developed within the project Reconfigurable Ubiquitous Networked Embedded Systems (RUNES). RUNES is a European Integrated Project with the aim to control complexity in networked embedded systems by developing robust and scalable middleware systems. New components for control under varying network conditions are discussed for the RUNES architecture. The paper highlights how the complexity of the closed-loop system is increased, due to additional disturbances introduced by the communication system: additional delays, jitter, data rate limitations, packet losses etc. Experimental work on integration test beds that demonstrates these results is presented, together with motivating links to the RUNES disaster relief tunnel scenario. ©2006 IEEE.

关键词： Embedded systems

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A Modified Numerical Integration Method for Deformable Object Animation

A Modified Numerical Integration Method for Deformable Objec...

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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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Kernelized Fuzzy c-means Method in Fast Segmentation of Demyelination Plaques in Multiple Sclerosis

Kernelized Fuzzy c-means Method in Fast Segmentation of Demy...

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29th Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBS 2007), vol.14

作者： Jacek Kawa Ewa Pietka Faculty of Automatic Control Electronics and Computer Science Department of Biomedical Engineering Gliwic Silesian University of Technology Gliwice Poland

Fuzzy c-means method (FCM) is a popular tool for a fuzzy data processing. In the current study, a FCM-based method of fuzzy clustering in a kernel space has been implemented. First, a "kernel trick" is applied to the fuzzy c-means algorithm. Then, the new method is employed for a fast automated segmentation of demyelination plaques in Multiple Sclerosis (MS). The clusters in a Gaussian kernel space are analysed in the histogram context and used during the initial classification of the brain tissue. Received classification masks are then used to detect the region of interest, eliminate false positives and label MS lesions.

关键词： Multiple sclerosis Kernel Clustering algorithms Image segmentation Prototypes Partitioning algorithms Lesions Magnetic resonance imaging Fuzzy sets Data processing

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Online Supervision of Penicillin Cultivations Based on Rolling MPCA

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Chinese Journal of Chemical engineering 2007年第1期15卷 92-96页

作者：汪志锋袁景淇 Department of Automatic Control Shanghai Jiao Tong University Shanghai 200030 China Department of AutomationShanghai Second Polytechnic University Shanghai 201209 China Department of Automatic Control Shanghai Jiao Tong University Shanghai 200030 China State Key Laboratory of Bioreactor Engineering East China University of Science & Technology Shanghai 200237 China

To reduce the variations of the production process in penicillin cultivations, a rolling multivariate statis-tical approach based on multiway principle component analysis (MPCA) is developed and used for fault diagnosis of penicillin cultivations. Using the moving data windows technique, the static MPCA is extended for use in dy-namic process performance monitoring. The control chart is set up using the historical data collected from the past successful batches, thereby resulting in simplification of monitoring charts, easy tracking of the progress in each batch run, and monitoring the occurrence of the observable upsets. Data from the commercial-scale penicillin fer-mentation process are used to develop the rolling model. Using this method, faults are detected in real time and the corresponding measurements of these faults are directly made through inspection of a few simple plots (t-chart, SPE-chart, and T2-chart). Thus, the present methodology allows the process operator to actively monitor the data from several cultivations simultaneously.

关键词： multiway principle component analysis fermentation online supervision fault diagnosis rolling

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Global Synchronization of Coupled Map Lattices

Global Synchronization of Coupled Map Lattices

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IEEE International Conference on Mechatronics and Automation

作者： Zhi Li Ju-Jang Lee Department of Automatic Control Engineering Xidian University Xi'an China Department of Electrical Engineering and Computer Science Korea Advanced Institute of Science and Technology Daejeon South Korea

Global synchronization of coupled map lattices are investigated in this paper. A sufficient condition for global synchronization is derived. Unlike other approaches, the coupled lattices is not linearized in this paper. Instead, the sufficient condition for the synchronization is obtained here by introducing a reference state along with Lyapunov function method, and this condition is simply given in terms of the maximum absolute value of eigenvalues of the coupling matrices those are not equal to one. Moreover, we give how to construct the coupling matrix to guarantee global synchronization of coupled map lattices based on two comparing matrices, which is very convenient to use. A typical example of coupled map lattices with chaotic nodes is finally used to verify the theoretical results and the effectiveness of the proposed synchronization scheme.

关键词： Lattices Sufficient conditions Lyapunov method Chaos Eigenvalues and eigenfunctions Stability Mechatronics Automation Linear matrix inequalities

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Inf-sup control of discontinuous piecewise affine systems 9

Inf-sup control of discontinuous piecewise affine systems

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2007 9th European control Conference, ECC 2007

作者： Spjotvold, J. Kerrigan, E.C. Rakovic, S.V. Mayne, D.Q. Johansen, T.A. Department of Engineering Cybernetics Norwegian University of Science and Technology Trondheim Norway Department of Aeronautics Department of Electrical and Electronic Engineering Imperial College London Exhibition Road LondonSW7 2AZ United Kingdom Automatic Control Laboratory Swiss Federal Institute of Technology Physikstrasse 3 ZurichCH-8092 Switzerland

ISBN: (纸本)9783952417386

In this paper we consider optimal control of constrained, discontinuous, discrete-time, piecewise affine systems with state and input dependent disturbances. We seek to precompute, via dynamic programming, an explicit control law for these systems when a piecewise affine cost function is utilized. The main difficulty with this problem class is that, even for initial states for which the value function of the optimal control problem is finite, there might not exist a control law that attains the infimum. Hence, we propose a method that is guaranteed to obtain a sub-optimal solution, and where the degree of sub-optimality can be specified a priori. This is achieved by approximating the underlying sub-problems with a piecewise parametric linear program. © 2007 EUCA.

关键词： Dynamic programming

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Adaptive digital synchronization of measuring window in low-cost DSP power quality measurement systems

Adaptive digital synchronization of measuring window in low-...

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International Conference on Electrical Power Quality and Utilisation (EPQU)

作者： Krzysztof Gorecki Miroslaw Szmajda Janusz Mroczka Department of Electrical Engineering Automatic Control and Computer Science Opole University of Technology Opole Poland Chair of Electronic and Photonic Metrology Wroclaw University of Technology Wroclaw Poland

The problems with the power quality encountered in cases of low voltage hospital power networks are increasingly common. It is due to the fact that there are usually a few power networks, backup power sources and a wild range of appliances. That situation may cause disturbances in power network and decrease the quality of electric energy. The problem is significant because power supply networks in hospitals provide electricity for very sensitive and expensive measuring apparatus which guards patients' life. These arguments led to creating relatively cheap systems of evaluating energy quality and disturbance detection. It presents not only hardware but also software optimization of the method of measuring the quality of electric energy which meets the basic standards (EN 50160, EN 61000-4- 7, EN 1000-4-30). The article justifies the usage of modern floating-point digital signal processor TMS320C6713 as a computing unit. It is a low budget alternative which can be used in other similar cases. Presented hardware selection has other additional specific features suitable for applying in hospital power supply network. The other part of the paper presents the algorithm of software which was implemented on DSP-system. It includes adaptive digital synchronization of the measuring window with power frequency. Also the algorithm for digital phase locked loop was presented.

关键词： Power measurement Digital signal processing Power quality Hospitals Frequency synchronization Electric variables measurement Hardware Signal processing algorithms Low voltage Home appliances

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Platform for Emulating Networked control Systems in laboratory Environments

Platform for Emulating Networked Control Systems in Laborato...

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IEEE International Symposium on World of Wireless Mobile and Multimedia Networks (WoWMoM)

作者： Shekar Nethi Mikael Pohjola Lasse Eriksson Riku Jantti Department Computer Science University of Vaasa Finland Control Engineering Laboratory Helsinki University of Technology Finland Communications Laboratory Helsinki University of Technology Finland

This paper discusses a platform for prototyping control schemes for networked control systems (NCS). The platform provides tools for simulating various networks in connection with real processes. The paper focuses on an extension to the MoCoNet platform [8], which is a unique environment for monitoring and controlling processes over the Internet in real-time. MoCoNet also provides capability of emulating different networks via network simulation. The platform is extremely valuable for control design in NCS, because the real processes can be first run over simulated networks and different network congestion scenarios can be experimented. This paper extends the MoCoNet system by integrating it with the well known and widely accepted network simulator [9], Ns2. The paper discusses various aspects of this novel integration of Ns2 with realtime operated control systems. The extension allows users of the MoCoNet system to test the control algorithms for NCS with numerous wired/wireless technologies available in Ns2. Furthermore, the paper discusses the development of a simple Java based GUI that is used to create virtual networks in Ns2.

关键词： Networked control systems control systems Prototypes Monitoring Process control Internet control design System testing Java Graphical user interfaces

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