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Spatio-temporal error concealment algorithms for encoded video streams for real-time applications

International Journal of computers and Applications 2012年第2期34卷 105-118页

作者： Sarhan, Amany Mahmoud, Rasha O. Faheem, Mohamed T. Computers and Automatic Control Engineering Department Faculty of Engineering Tanta University Egypt Computer Science Department Nile Institute of Commerce and Computer Technology Mansoura Egypt Computers and Automatic Control Engineering Department Faculty of Engineering Taief University Saudi Arabia

Multimedia is one of the most important aspects of the information era. With the advent of the multimedia age and the spread of Internet, video storage and streaming has been gaining a lot of popularity. When transmitting compressed video over a data network channel errors affect the decoding process. Video transmission puts constraints on data rate, computational complexity and delay. Unreliable channels add more challenges to this task as compressed video is extremely vulnerable to transmission errors. Problems arising from imperfect transmission of block coded video frame sequence result in lost blocks. This paper presents and implements a set of decoder side spatio-temporal algorithms that aim to enhance the speed and quality of the error concealment process. The results obtained by these algorithms are much faster and achieve better performance compared to the existing algorithms, which make them more suitable for real-time applications.

关键词： Image communication systems

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control of the hydraulic drive using embedded control system

Control of the hydraulic drive using embedded control system

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International Carpathian control Conference (ICCC)

作者： Petr Noskievič Department of automatic control and Instrumentation Faculty of Mechanical Engineering VŠB-Technical University of Ostrava Ostrava Czech Republic

ISBN: (纸本)9781467344883

The topic of the paper is a design of the embedded control system for hydraulic drive. The design of the control algorithm is based on the simulation model of the controlled technology and hydraulic drive. Final testing was realized using the Hardware in the Loop Simulation and the developed program was implemented in the embedded control system. The result of the testing on the test rig confirmed the quality of the closed loop control using the designed embedded control system.

关键词： Tuning Frequency modulation

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Structured coprime factorizations description of linear and time-invariant networks

Structured coprime factorizations description of linear and ...

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52nd IEEE Conference on Decision and control, CDC 2013

作者： SabǍu, Şerban OarǍ, Cristian Warnick, Sean Jadbabaie, Ali Electrical and Computer Engineering Dept. Stevens Institute of Technology United States Faculty of Automatic Control Dept. University Politehnica Bucharest Romania Faculty of Computer Science Department Information and Decision Algorithms Laboratories Brigham Young University United States Faculty of Electrical and Systems Engineering Dept. University of Pennsylvannia United States

ISBN: (纸本)9781467357173

In this paper we study state-space realizations of Linear and Time-Invariant (LTI) systems. Motivated by biochemical reaction networks, Gonçalves and Warnick have recently introduced the notion of a Dynamical Structure Functions (DSF), a particular factorization of the system's transfer function matrix that elucidates the interconnection structure in dependencies between manifest variables. We build onto this work by showing an intrinsic connection between a DSF and certain sparse left coprime factorizations. By establishing this link, we provide an interesting systems theoretic interpretation of sparsity patterns of coprime factors. In particular we show how the sparsity of these coprime factors allows for a given LTI system to be implemented as a network of LTI sub-systems. We examine possible applications in distributed control such as the design of a LTI controller that can be implemented over a network with a pre-specified topology. ©2013 IEEE.

关键词： Factorization

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A novel adaptive spiral dynamic algorithm for global optimization

A novel adaptive spiral dynamic algorithm for global optimiz...

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UK Workshop on Computational Intelligence (UKCI)

作者： A. N. K. Nasir M. O. Tokhi O. Sayidmarie R. M. T. Raja IsmaiL Department of Automatic Control & Systems Engineering University of Sheffield Sheffield UK Faculty of Electrical and Electronics Engineering Universiti Malaysia Pahang Pahang Malaysia

This paper presents a novel adaptive spiral dynamic algorithm for global optimization. Through a spiral model, spiral dynamic algorithm has a balanced exploration and exploitation strategy. Defining suitable value for the radius and displacement in its spiral model may lead the algorithm to converge with high speed. The dynamic step size produced by the model also allows the algorithm to avoid oscillation around the optimum point. However, for high dimension problems, the algorithm may easily get trapped into local optima. This is due to the incorporation of a constant radius and displacement in the model. In order to solve the problem, a novel adaptive formulation is proposed in this paper by varying the radius and displacement of the spiral model. The proposed algorithm is validated with various dimensions of unimodal and multimodal benchmark functions. Furthermore, it is applied to parameter optimization of an autoregressive with exogenous terms dynamic model of a flexible manipulator system. Comparison with the original spiral dynamic algorithm shows that the proposed algorithm has better accuracy. Moreover, the time domain and frequency domain responses of the flexible manipulator model shows that the proposed algorithm outperforms its predecessor algorithm.

关键词： Heuristic algorithms Spirals Adaptation models Algorithm design and analysis Manipulator dynamics Convergence Benchmark testing

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One variant of self-tuning DC motor adaptive controller

One variant of self-tuning DC motor adaptive controller

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Proceedings of the International Convention MIPRO

作者： Ž. Jurić H. Šiljak Department of Automatic Control & Electronics Faculty of Electrical Engineering Sarajevo Bosnia and Herzegovina Department of Electrical & Electronics Engineering International Burch University Sarajevo Bosnia and Herzegovina

This paper proposes a self-tuning adaptive controller in order to produce response of a second order block from the typically nonlinear motor. Periodic reset of controller's estimator block is employed as an improvement of the original design. Classical model of DC motor is well-controlled via this improved controller, while for the system containing a motor and thyristor-fired phase-controlled rectifier a new improvement is introduced, the arcsine compensation block. controller is tested in different simulation conditions and it shows high ability to compensate any effects, produced either by the reference value change or the external error induced by load or thyristor rectifier.

关键词： Rectifiers Mathematical model Voltage control DC motors Equations Covariance matrices Convergence

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Actuator-fault Detection and Isolation based on Interval Observers and Invariant Sets

Actuator-fault Detection and Isolation based on Interval Obs...

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IEEE Annual Conference on Decision and control

作者： Feng Xu Vicen? Puig Carlos Ocampo-Martinez Florin Stoican Sorin Olaru Institut de Robotica i Informatica Industrial (CSIC-UPC) Technical University of Catalonia (UPC) Llorens i Artigas 4-6 08028 Barcelona Spain Dept. of Automatic Control and Systems Engineering Faculty of Automatic Control and Computers "Politehnica" University of Bucharest 313 Spl. Independentei 060042 Bucharest Romania E3S (SUPELEC Systems Sceinces) Automatic Control Departement Gif sur Yvette France

ISBN: (纸本)9781467357159;9781467357159

This paper proposes an interval observer-based actuator fault detection and isolation (FDI) approach. An interval observer matching the healthy system mode is designed to monitor the system. When the system is in different modes, state or output interval vectors predicted by the interval observer manifest different dynamical behaviors. To guarantee reliable FDI, a collection of invariant set-based FDI conditions are established. Under these conditions, actuator faults can be accurately detected and isolated during the transition between different modes. At the end, the effectiveness of this proposed approach is presented by using a numerical example.

关键词： FDI Actuator-fault Detection Invariant Sets

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control synthesis for switched systems with control and state constraints

Control synthesis for switched systems with control and stat...

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Mediterranean Conference on control & Automation

作者： H. N. Nguyen S. Olaru P. O. Gutman Faculty of Civil and Environmental Engineering Technion - Israel Institute of Technology SUPELEC Systems Sciences (E3S) - Automatic Control Department

ISBN: (纸本)9781479909964

In this paper, a new interpolation based control is developed for constrained control of switched linear discrete-time systems. The interpolation is done between a global gain-scheduled vertex controller and a local gain-scheduled stabilizing controller in order to achieve both the large domain of attraction and performance. At each time instant a linear programming problem is solved on-line. Proofs of recursive feasibility and asymptotic stability are given.

关键词： Switched systems Standing Orders region of attraction asymptotic stability region system control linear programming Interpolation controllers synthesis

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In-flight calibration of attitude determination systems for information mini-satellites?

In-flight calibration of attitude determination systems for ...

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19th IFAC Symposium on automatic control in Aerospace, ACA 2013

作者： Somov, Ye. Butyrin, S. Siguerdidjane, H. Hajiyev, Ch. Fedosov, V. Samara State Technical University Department of Guidance Navigation and Control 244 Molodogvardeyskaya Str. Samera 443100 Russia Ecole Superieure d'Electricite Automatic Control Department Gif-sur-Yvette 91192 France Istanbul Technical University Aeronautics and Astronautics Faculty Maslak Istanbul 34469 Turkey Czech Space Engineering Institute 17 Santosky Str. 15000 Prague 5 Czech Republic

ISBN: (纸本)9783902823465

Contemporary information mini-satellites have general mass up to 500 kg and are placed onto the orbit altitudes from 500 up to 1500 km. For such spacecraft some principle problems on precise attitude determination and in-ight calibration are considered and elaborated methods are presented for their solving. Original multiple discrete algorithms for filtering, integration and calibration of a strapped-down inertial navigation system for precise determining the spacecraft attitude, are presented. This system contains electrostatic microaccelerometer, an inertial measurement unit based on the gyro sensors, an astronomical system based on star trackers, multi-head Sun sensor and magnetic sensor, the that are fixed to the spacecraft body. © IFAC.

关键词： Calibration

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Development of parallel manipulator sit to stand assistive device for elderly people

Development of parallel manipulator sit to stand assistive d...

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2013 IEEE Workshop on Advanced Robotics and Its Social Impacts, ARSO 2013

作者： Salah, Omar Asker, Ahmed Fath El-Bab, Ahmed M. R. Assal, Samy M. F. Ramadan, Ahmed A. Sessa, Salvatore Abo-Ismail, Ahmed Egypt-Japan University of Science and Technology New Borg-El-Arab city Alexandria Egypt Mechanical Engineering Department Faculty of Engineering Assiut University Egypt Department of Production Engineering and Mechanical Design Faculty of Engineering Tanta University Alexandria Egypt Computer and Automatic Control Dept. Faculty of Engineering Tanta University Tanta Egypt Mechatronics and Robotics Dept. Egypt-Japan University of Science and Technology Egypt School of Creative Science and Engineering Waseda University Tokyo 168-8480 Japan

ISBN: (纸本)9781479923694

This paper describes a novel mobility assistive device under development in the Egypt-Japan University of Science and Technology (E-JUST). The proposed system can help patients who do not have enough physical strength on the lower limbs during sit to stand due to aging, diseases such as polymyositis and myopathy, and joint replacement surgery complications. It can follow the natural pattern of human motion during sit to stand providing assistance force under the shoulder. The overall device is compact and employees a parallel mechanism which provide more stiffness. Several experiments were carried out in a VICON room to calculate the human motion posture while sit to stand motion in addition estimate the trajectory of the end effector during assisting. Computer simulation was built to verify the performance of the proposed system with the reference trajectory. © 2013 IEEE.

关键词： Mechanisms

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On Structured Realizability and Stabilizability of Linear systems

On Structured Realizability and Stabilizability of Linear Sy...

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American control Conference

作者： Laurent Lessard Maxim Kristalny Anders Rantzer Department of Mechanical Engineering at the University of California Berkeley Berkeley CA 94720 USA Faculty of Mechanical Engineering Technion Israel Institute of Technology Haifa 32000 Israel Department of Automatic Control at Lund University Lund Sweden

ISBN: (纸本)9781479901777

We study the notion of structured realizability for linear systems defined over graphs. A stabilizable and detectable realization is structured if the state-space matrices inherit the sparsity pattern of the adjacency matrix of the associated graph. In this paper, we demonstrate that not every structured transfer matrix has a structured realization and we reveal the practical meaning of this fact. We also uncover a close connection between the structured realizability of a plant and whether the plant can be stabilized by a structured controller. In particular, we show that a structured stabilizing controller can only exist when the plant admits a structured realization. Finally, we give a parameterization of all structured stabilizing controllers and show that they always have structured realizations.

关键词： Linear systems associated plant Linear system plants stabilizability controllers transfer matrix

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