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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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Balanced routing algorithm based on the relay in linear WSN

International Journal of Digital Content Technology and its ...

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International Journal of Digital Content Technology and its Applications 2012年第7期6卷 142-150页

作者： Bao-Juan, Liang Yong-Feng, Ju Shao-Bo, Sun School of Electronic and Control Engineering Chang'an University China Department of Computer Science Xi'an University of Arts and Science China

The online real-time monitoring of high voltage power for transmission line can be realized. After deeply researching the special topology of linear wireless sensor network used in the monitoring system of high voltage power transmission line, this paper proposed routing algorithm of nodes relay times balancing in linear WSN. The algorithm takes nodes relay times into account and divides the nodes of sensor network into clusters and cluster groups to establish a two- tiered network structure. According to the routing table of relay times, the nodes decide whether join the data packet routing or not, which can ensure the times balance of relay routing in the whole sensor network and extend the life cycle of the network.

关键词： Life cycle

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Power fundamental frequency detection based on orthometric average chirp-z transform

Power fundamental frequency detection based on orthometric a...

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18th International Conference on Automation and Computing, ICAC 2012

作者： Liu, Guangfu Dong, Zidi Yang, Shuanghua Zhao, Xinju College of Information and Control Engineering China University of Petroleum Qingdao 266555 China Computer Science Department Loughborough University Loughborough LE11 3TU United Kingdom

ISBN: (纸本)9781908549006

Chirp-z transform (CZT) is usually used to refine frequency spectrum to analyze special frequency. The spectral resolution by CZT can be small as one wants but sometimes is wrongly considered as the same as accuracy. This paper discussed some characters of CZT about accuracy for monotone frequency signals. The CZT error decreases when the sampling time increases, and fluctuates periodically and diminishingly until reaches the resolution. The error distribution is related to the initial phase of the sampled signal. The spectral results are approximately symmetrical for two orthometric signals. A new frequency analyzing method, orthometric average chirp-z transform (OACZT), is presented to analyze the power fundamental frequency more exactly. Simulation results show that the accuracy of OACZT is about 0.003Hz with sampling time of 0.2s, better than CZT with an accuracy of about 0.1Hz. © 2012 CACSUK.

关键词： Natural frequencies

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Energy aware TLM platform simulation via RTL abstraction

Energy aware TLM platform simulation via RTL abstraction

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IEEE International High-Level Design Validation and Test Workshop

作者： Nicola Bombieri Franco Fummi Valerio Guarnieri Andrea Acquaviva Department of Computer Science University of Verona Italy Department of Control and Computer Engineering Politecnico di Torino Italy

Energy consumption estimation is nowadays one of the most pressing concerns in the design of embedded systems. In order to provide power estimates, techniques have been developed to enable energy-aware simulation of CPU models at different abstraction levels, such as register-transfer level (RTL) and software through an instruction set simulator (ISS). However, the chosen abstraction level heavily affects the outcome of the simulation in terms of speed and accuracy. RTL simulations are more accurate because of their wealth in terms of implementation details, but require significant computation times. ISS simulations run much faster, but are affected by a loss of accuracy due to their software implementation. Transaction-level modeling (TLM) simulations provides an ideal trade-off between speed and accuracy, but they rely on the creation of a TLM platform which is usually not available and must be manually created. In this context, we propose a methodology to automatically abstract a starting RTL CPU description into a corresponding TLM description. The abstraction methodology preserves details required to perform an energy-aware simulation, such as timing accuracy and instruction counts.

关键词： Computational modeling Time varying systems Time domain analysis Data structures Ports (computers) Protocols Estimation

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A distributed particle swarm optimization based localization scheme in underground tunnels

A distributed particle swarm optimization based localization...

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IET Conference on Wireless Sensor Systems (WSS 2012)

作者： Yuanqing Qin Fang Wang Chunjie Zhou Shuang-Hua Yang Department of Control Science & Engineering Huazhong University of Science and Technology China Computer Science Department Loughborough University UK

ISBN: (纸本)9781622762835

One of the main concerns in underground working tunnels is ensuring the safety of the workers and their equipment. Being aware of the real-time position of personal in such hash environments is challenging and requires a sophisticated localization system. Due to extreme multipath and non-line of sight (NLOS) conditions, wireless signals in underground narrow-vein tunnels suffer multiple kinds of distortions. Unreliable measurements of location metrics such as received signal strengths (RSS), result in deterioration of localization performance. In this paper, a radio frequency time of flight (RF-TOF) range engine embedded in JN5148 microcontroller is validated as an alternative range method in such scenarios. To reduce the communication cost and time delay of localization in such chain type wireless network, a distributed particle swarm optimization (PSO) based localization algorithm is proposed and implemented on the blind node. Without overhead hardware needed, an accurate and low cost localization system can be achieved. Experimental results verify the proposed scheme.

关键词： Wireless sensor networks Localization Particle swarm optimization Time of flight Tunnels tunnel underground Particle swarm optimization indium

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Adaptive neural control for MIMO nonlinear systems with state time-varying delay

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控制理论与应用（英文版） 2012年第3期10卷 309-318页

作者： Ruliang WANG Kunbo MEI Chaoyang CHEN Yanbo LI Hebo MEI Zhifang YU Computer and Information Engineering College Guangxi Teachers Education University Nanning Guangxi 530023 China School of Mathematical Sciences Guangxi Teachers Education University Nanning Guangxi 530023 China Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan Hubei 430074 China Information Engineering College Capital Normal University Beijing 100048 China School of Education Sciences Guangxi Teachers Education University Nanning Guangxi 530023 China

In this paper, adaptive neural control is proposed for a class of multi-input multi-output （MIMO） nonlinear unknown state time-varying delay systems in block-triangular control structure. Radial basis function （RBF） neural net- works （NNs） are utilized to estimate the unknown continuous functions. The unknown time-varying delays are compensated for using integral-type Lyapunov-Krasovskii functionals in the design. The main advantage of our result not only efficiently avoids the controller singularity, but also relaxes the restriction on unknown virtual control coefficients. Boundedness of all the signals in the closed-loop of MIMO nonlinear systems is achieved, while The outputs of the systems are proven to converge to a small neighborhood of the desired trajectories. The feasibility is investigated by two simulation examples.

关键词： Adaptive control Backstepping technique Time-varying delay MIMO Neural network

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OUTPUT FEEDBACK FAULT TOLERANT control FOR NETWORKED control SYSTEMS WITH RANDOM ACCESS

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control AND INTELLIGENT SYSTEMS 2012年第4期40卷 226-233页

作者： Qi, Xiaomei Zhang, Chengjin Gu, Jason School of Control Science and Engineering Shandong University Jinan China Department of Electrical and Computer Engineering Dalhousie University Halifax Canada

An output-feedback fault tolerant control problem for networked control system (NCS) with network-induced delay and data packet dropout is investigated. In both sensor-to-controller link and controller-to-actuator link, the total time-varying and unknown network-induced delay can be separated into two parts, that is, one is a constant and the other is a bounded variable. The effect of the network-induced delay is transformed into model uncertainty. The data packet dropout is modelled as two switches that follow a four-state Markov chain. Then a discrete-time Markovian jump uncertain model of NCS with actuator (complete/partial) failure is established. The sufficient and necessary condition for exponential mean square stability is derived. Moreover, a linear matrix inequality approach for designing switching output-feedback controllers are presented. Finally, two numerical examples are presented to illustrate the effectiveness of the proposed method.

关键词： Fault tolerant control time-varying and unknown network-induced delay data packet dropout Markov chain switching output-feedback controllers

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Distribution-aware mutation analysis

Distribution-aware mutation analysis

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36th Annual IEEE International computer Software and Applications Conference Workshops, COMPSACW 2012

作者： Sun, Chang-Ai Wang, Guan Cai, Kai-Yuan Chen, Tsong Yueh School of Computer and Communication Engineering University of Science and Technology Beijing Beijing China Department of Automatic Control Beijing University of Aeronautics and Astronautics Beijing China State Key Laboratory of Computer Science Institute of Software Chinese Academy of Science Beijing China Facuity of Information and Communication Technologies Swinburne University of Technology Melbourne VIC Australia

ISBN: (纸本)9780769547589

Mutation analysis is widely employed to evaluate the effectiveness of various software testing techniques. In most situations, mutation operators are uniformly applied to the original programs, while the faults tend to be clustered in practice. This may result in the inappropriate simulation of faults, and thus cannot deliver the reliable evaluation results. To overcome this, we propose a distribution-aware mutation analysis technique and conducted empirical studies to investigate the impact of the mutation distribution on the effectiveness evaluation of testing techniques. As an illustration, we select the commonly practiced random testing technique and two versions of dynamic random testing techniques and apply them to testing Web services. Results of empirical studies suggest that the mutation distribution significantly affects the evaluation results. This observation further indicates that the effectiveness of testing techniques previously evaluated with the uniform mutation analysis needs further realignments. © 2012 IEEE.

关键词： Software testing

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Actionable topological mapping for navigation using nearby objects

Actionable topological mapping for navigation using nearby o...

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2012 IEEE International Conference on Automation science and engineering: Green Automation Toward a Sustainable Society, CASE 2012

作者： Kim, Junyoung Kim, Juyong You, Seungil Oh, Yoonseon Oh, Songhwai School of Electrical Engineering and Computer Science and ASRI Seoul National University Seoul 151-744 Korea Republic of Department of Control and Dynamical Systems California Institute of Technology Pasadena CA 91125 United States

ISBN: (纸本)9781467304283

In this paper, we propose a mapping and navigation method for mobile robots with low computational resources and limited memory capacity. The proposed navigation method is based on topological mapping of visual features for its compact representation and robustness in localization. In order to improve the localization accuracy and minimize the memory requirement, we propose the use of visual features from nearby objects. This paper presents a new topological map, called an actionable topological map, which is constructed using visual features from nearby objects and motion information between places in the map. By incorporating motion information, we make it easier for a robot to navigate using the compact representation of a topological map. The proposed method is suitable for light-weight, low-cost robotic platforms due to its low computational and space requirements. We demonstrate the effectiveness of our approach in experiments using an inexpensive, off-the-shelf robotic platform. © 2012 IEEE.

关键词： Mobile robots

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New predictive control scheme for networked control systems

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Circuits, Systems, and Signal Processing 2012年第3期31卷 945-960页

作者： Liu, Bo Xia, Yuanqing Mahmoud, Magdi S. Wu, Harris Cui, Shisheng Department of Automatic Control Beijing Institute of Technology Beijing 100086 China Systems Engineering Department King Fahd University of Petroleum and Minerals PO Box 5067 Dhahran 31261 Saudi Arabia College of Business and Public Administration Old Dominion University Norfolk VA 23529 United States Computer Science Department Stanford University Stanford CA 94305 United States

This paper is concerned with the design of networked control systems with random network-induced delay and data dropout. It presents a new control scheme, which is termed networked predictive control with optimal estimation. Based onMultirate Kalman Filtering, the measured data which are out of sequence or delayed can be used to improve the precision of estimation. The control prediction generator provides a set of future control predictions to make the closed-loop system achieve the desired control performance and the compensator removes the effects of the network transmission with time delay and data dropout. Simulation results are presented to illustrate the effectiveness of the control strategy via comparing with control schemes without any compensation for the network. © Springer science+Business Media, LLC 2011.

关键词： Networked control systems

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