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Attitude and Handling Improvements Through Gain-scheduled Suspensions and Brakes Control

IFAC Proceedings Volumes 2008年第2期41卷 2075-2080页

作者： C. Poussot-Vassal O. Sename L. Dugard P. Gáspár Z. Szabó J. Bokor GIPSA-lab Control Systems Department (former LAG) INPG-CNRS-ENSIEG - Domaine Universitaire BP46 38402 Saint Martin d'Hères - Cedex FRANCE Computer and Automation Research Institute Hungarian Academy of Sciences Kende u. 13-17 H-1111 Budapest HUNGARY

In this paper, the problem of comfort and handling improvements of a ground vehicle is treated through the control of the suspension and braking systems. Two gain-scheduled controllers are synthesized (in the H ∞ framework) to achieve, in the frequency domain, comfort and yaw performances according to the driving situation, observed by the mean of a monitor. The proposed strategy tackles the nonlinear tire braking force in an original way and meets the situation dependent objectives of the vehicle in a unified synthesis. Simulation tests on a complex nonlinear full vehicle model shows improvements of the proposed approach.

关键词： H ∞ Linear Parameter Varying Suspensions Brakes Global Chassis Control Anti-locking Braking System Electronic Stability Control

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Enhanced Biologically Inspired Model

Enhanced Biologically Inspired Model

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26th IEEE Conference on computer Vision and Pattern Recognition (CVPR 2008), vol.7

作者： Yongzhen Huang Kaiqi Huang Liangsheng Wang Dacheng Tao Tieniu Tan Xuelong Li National Laboratory of Pattern Recognition Institute of Automation Chinese Academy and Sciences Beijing China Biometrics Research Centre Department of Computing Hong Kong Polytechnic University Hong Kong China School of Computer Science and Information Systems Birkbeck University of London London UK

It has been demonstrated by Serre et al. that the biologically inspired model (BIM) is effective for object recognition. It outperforms many state-of-the-art methods in challenging databases. However, BIM has the following three problems: a very heavy computational cost due to dense input, a disputable pooling operation in modeling relations of the visual cortex, and blind feature selection in a feedforward framework. To solve these problems, we develop an enhanced BIM (EBIM), which removes uninformative input by imposing sparsity constraints, utilizes a novel local weighted pooling operation with stronger physiological motivations, and applies a feedback procedure that selects effective features for combination. Empirical studies on the CalTech5 database and CalTech101 database show that EBIM is more effective and efficient than BIM. We also apply EBIM to the MIT-CBCL street scene database to show it achieves comparable performance in comparison with the current best performance. Moreover, the new system can process images with resolution 128 × 128 at a rate of 50 frames per second and enhances the speed 20 times at least in comparison with BIM in common applications.

关键词： Biological system modeling Spatial databases Image databases Brain modeling Object recognition Visual databases Computational efficiency Feedforward systems Feedback Layout

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Handling User Preferences and Added Value in Discovery of Semantic Web Services

Handling User Preferences and Added Value in Discovery of Se...

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IEEE International Conference on Web Services (ICWS)

作者： Laszlo Kovacs Andras Micsik Peter Pallinger Department of Distributed Systems MTA SZTAKIComputer and Automation Research Institute Hungarian Academy of Sciences (ATOMKI) Budapest Hungary

This paper presents the discovery engine implemented for the INFRAWEBS project, which combines a traditional IR-based pre-filtering step and a logic-based matching implemented in Prolog. The logic-based step of discovery uses a novel technique based on Prolog-style unification of terms. This approach performs well in finding matches of intersection type, and it also provides possibilities to compare, rank and explain these matches. Furthermore, it can support matching and ranking based on users' preferences compared to the added value offered by services.

关键词： Semantic Web Engines Impedance matching Web services distributed computing automation Logic Information retrieval Application software Ontologies

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Color models of shadow detection in video scenes

Color models of shadow detection in video scenes

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2nd International Conference on computer Vision Theory and Applications, VISAPP 2007

作者： Benedek, Csaba Sziranyi, Tamas Department of Information Technology Pázmány Péter Catholic University Práter utca 50/A Budapest Hungary Distributed Events Analysis Research Group Computer and Automation Institute Kende u. I3'17 Budapest Hungary

In this paper we address the problem of appropriate modelling of shadows in color images. While previous works compared the different approaches regarding their model structure, a comparative study of color models has still missed. This paper attacks a continuous need for defining the appropriate color space for this main surveillance problem. We introduce a statistical and parametric shadow model-framework, which can work with different color spaces, and perform a detailed comparision with it. We show experimental results regarding the following questions: (1) What is the gain of using color images instead of grayscale ones? (2) What is the gain of using uncorrelated spaces instead of the standard RGB? (3) Chrominance (illumination invariant), luminance, or "mixed" spaces are more effective? (4) In which scenes are the differences significant? We qualified the metrics both in color based clustering of the individual pixels and in the case of Bayesian foreground-background- shadow segmentation. Experimental results on real-life videos show that CIE L*u*v* color space is the most efficient.

关键词： Color

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Federated filtering for fault tolerant estimation and sensor redundancy management in coupled dynamics distributed systems

Federated filtering for fault tolerant estimation and sensor...

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2007 Mediterranean Conference on Control and automation, MED

作者： Edelmayer, A. Miranda, M. Systems and Control Laboratory Computer and Automation Research Institute Hungarian Academy of Sciences Kende u. 13-17 Budapest H-1111 Hungary Faculty of Engineering Department of Chemical Engineering Mérida Venezuela

ISBN: (纸本)142441282X

This paper discusses the application of the idea of federated filtering to the estimation of intrinsically nonlinear distributed systems by examining its impacts on filtering performance by using the Extended Kalman Filter (EKF) as state estimator. Specifically, the performance of the traditional centralized solution is compared with the filtering structure obtained using the federating idea, and their conceptions, and their ability to balance between fault tolerance and estimation accuracy is examined. Our research demonstrates how successfully the EKF for solving nonlinear estimation problems in federated structures can be used, noting that the idea of federation have only been demonstrated for linear problems previously. In addressing the demands of both fault tolerance and estimation accuracy, it is shown that increased filtering accuracy is relied on the proper choice of sharing of the error covariance information between local filters, while sensor fault tolerance is provided by the utilization of an appropriate resetting policy of the filter. ©2007 IEEE.

关键词： Fault tolerance

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SIP security problems in NGM Services

SIP security problems in NGM Services

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International Conference on Next Generation Mobile Applications, Services and Technologies (NGMAST)

作者： Ferenc Leitold Anna Medve Levente Kovacs Department of Information Systems University of Pannonia Hungary Computer and Automation Research Institute Hungarian Academy of Sciences (ATOMKI) Hungary

A variety of wireless interfaces are available to access Internet content in a heterogeneous network composed by technologies with limited QoS abilities. Performance increasing solutions become economic in specific parts of the network architecture, as the network sizes and the clients' numbers increase. SIP is used to locate the called party to check that the capabilities of the calling and called parties are consistent and to establish and control the connection. In this paper, we propose an addition to the SIP header/message compression methodology to improve the network QoS by implementations of SIP protocol quality options. We also deal with related SIP security issues regarding practicality and realization possibilities. This paper would like to highlight that security vulnerabilities, open problems may exist using the SIP protocol in usual cases of the practical usage.

关键词： Quality of service Next generation networking Information systems Access protocols Wireless networks computer security Information security automation IP networks computer architecture

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A Far-Range Off-line Camera Calibration Method for Stereo Lane Detection systems

A Far-Range Off-line Camera Calibration Method for Stereo La...

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IEEE Instrumentation and Measurement Technology Conference

作者： Andras Bodis-Szomoru Tamas Daboczi Zoltan Fazekas Department of Measurement and Information Systems Budapest University슠of슠Technology슠and슠Economics Hungary Systems and Control Laboratory Computer and Automation Research Institute Hungary

A far-range camera calibration method for vision sensors used in automatic lane detection systems is investigated. Autonomous vehicle guidance based on stereo image acquisition requires the knowledge of the camera parameters, such as camera position, orientation, lens distortion, focal length etc. with high precision. Calibration is performed by placing markers in known positions in front of the vehicle holding the camera(s) and by detecting the location of their images in the acquired snapshots. The parameters are then estimated by minimizing the geometric error in the image. Most of the methods discovered in the literature do not consider errors in the measurement of marker locations. However, a precise marker arrangement for far-range calibration might be expensive to set up. This paper shows that imprecision in the 3D location of the markers can not be tolerated in some practical situations and in such cases, a different optimization is proposed in the calibration of the extrinsic camera parameters (camera position and orientation). A position estimation method is also shown to extract marker positions from far-range laser distance meter measurements. The estimated marker positions are corrected by considering aiming errors, as well. Parameter errors are also estimated. It will be shown that our new calibration and optimization method is expected to result a good accuracy compared to commercial methods.

关键词： Cameras Calibration Remotely operated vehicles Sensor systems Mobile robots Navigation Lenses Vehicle detection Parameter estimation Position measurement

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MODELING AND CONTROL OF ELEVATORS BY STATECHARTS

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Asian Journal of Control 2008年第2期6卷

作者： Yi-Sheng Huang Sheng-Luen Chung Mu-Der Jeng Department of Aeronautical Engineering Chung Cheng Institute of Technology National Defense University Tashi Taoyuan 335 Taiwan R.O.C. Department of Electrical Engineering National Taiwan University of Science and Technology Taipei 106 Taiwan R.O.C. Department of Electrical Engineering National Taiwan Ocean University Kellung 202 Taiwan R.O.C. MuDer Jeng received the Ph.D. degree in computer and systems engineering from Rensselaer Polytechnic Institute Troy NY in 1992. Since August 1992 Dr. Jeng has been with National Taiwan Ocean University Keelung Taiwan where he is currently a full Professor at the Department of Electrical Engineering. His current research interests include Petri nets discrete event systems computer integrated manufacturing semiconductor factory automation embedded systems. Dr. Jeng is the author/co-author of over 120 book chapters journal papers and conference papers. Dr. Jeng received the Franklin V. Taylor Outstanding Paper Award from the IEEE Systems Man and Cybernetics Society in 1993. He was granted the Research Award by the National Science Council of Taiwan annually from 1994 to 2000. He is an Associate Editor for IEEE Transactions on Systems Man and Cybernetics-Part A IEEE Transactions on Robotics and Automation IEEE Transactions on Robotics and serves on the Editorial Board of International Journal of Computer Integrated Manufacturing. He has been a Guest Editor for eight leading journals. Dr. Jeng is the Chair of the Technical Committee on Discrete Event Systems of the IEEE SMC Society and the Founding Chair of the Technical Committee on Semiconductor Factory Automation of the IEEE Robotics and Automation Society. He served as the Exhibitions Chair of 2003 IEEE International Conference on Robotics and Automation and the Special Sessions Chair of 2004 IEEE International Conference on Networking Sensing and Control. He serves as a Program Co-Chair of 2005 IEEE International Conference on Networking Sensing and Control and the Organization Commit

Statechart has been utilized as a visual formalism for the modeling of complex and interactive systems for its illuminating features on describing properties of causality, concurrency, and synchronization. This paper presents the application of satechart to the modeling, design and implementation of an elevator system, whose system behavior involves aggregating complexity of state descriptions, and imposition of underlying control policy. Based on the operational flow of an elevator, we derive the associated statechart model by looking into the inherent hierarchical structure of the elevator. The advantage of the proposed approach is the clear presentation of system behavior in terms of conditions and events that cause the transitions in system dynamics. Implementation of the controlled elevator based on the modeled statechart is also presented.

关键词： Statechart interactive systems elevator

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Selective Gas Sensor System for CO and H2 Distinction at High Temperatures Based on a Langasite Resonator Array

Selective Gas Sensor System for CO and H2 Distinction at Hig...

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International Conference on Solid State Sensors and Actuators (TRANSDUCERS)

作者： D. Richter T. Schneider S. Doerner H. Fritze P. Hauptmann Department of Automation and Computer Science University of Applied Studies and Research Wernigerode Germany Institute of Micro and Sensor Systems Otto-von-Guericke University of Magdeburg Magdeburg Germany

A selective in-situ gas sensor system for CO and H 2 distinction at high temperatures has been developed based on an array of piezoelectric langasite resonators. Bulk acoustic wave resonators coated with different sensing films are operated in two different measurement modes which increases the selectivity of the gas sensor system. Simultaneously, a compact and rapid impedance analyzer for precise resonant frequency measurement of the strongly damped resonators has been developed and allows the standalone application for the sensor system.

关键词： Sensor arrays Gas detectors Hydrogen Temperature sensors Acoustic measurements Acoustic waves Film bulk acoustic resonators Piezoelectric films Impedance Resonant frequency

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Impact of Non-Poissonian Activity Patterns on Spreading Processes

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Physical Review Letters 2007年第15期98卷 158702-158702页

作者： Alexei Vazquez Balázs Rácz András Lukács Albert-László Barabási The Simons Center for Systems Biology Institute of Advanced Study Einstein Drive Princeton New Jersey 08540 USA Computer and Automation Research Institute Hungarian Academy of Sciences (MTA SZTAKI) Budapest Hungary Department of Physics and Center for Complex Networks Research University of Notre Dame Notre Dame Indiana 46556 USA

Halting a computer or biological virus outbreak requires a detailed understanding of the timing of the interactions between susceptible and infected individuals. While current spreading models assume that users interact uniformly in time, following a Poisson process, a series of recent measurements indicates that the intercontact time distribution is heavy tailed, corresponding to a temporally inhomogeneous bursty contact process. Here we show that the non-Poisson nature of the contact dynamics results in prevalence decay times significantly larger than predicted by the standard Poisson process based models. Our predictions are in agreement with the detailed time resolved prevalence data of computer viruses, which, according to virus bulletins, show a decay time close to a year, in contrast with the 1 day decay predicted by the standard Poisson process based models.

关键词： .Poisson process prevalence spreading activity patterns PRL week time distribution viruses decay times

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