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IEEE International Workshop on Imaging Systems and Techniques (IST)

作者： Daniel G. Costa Luiz Affonso Guedes Francisco Vasques Paulo Portugal Department of Computing and Automation Federal University of Rio Grande do Norte Brazil IDMEC/ISR Faculty of Engineering University of Porta Portugal Department of Technology State University of Feira de Santana Brazil

Wireless sensor networks composed of camera-enabled source nodes can provide visual information of an area of interest, potentially enriching monitoring applications. While few bytes can represent scalar data, even low-resolution still images may require thousand of bytes, turning data fragmentation into a relevant design issue. Different optimization approaches have been proposed in recent years to achieve energy saving in wireless image sensor networks. However, the impact of image fragmentation upon the adopted MAC technology has been neglected in most cases. In this work we investigate the effect of frame size on image transmissions over wireless sensor networks, linking the maximum frame size, the useful payload and the frame error rate effects. Additionally, we discuss different approaches for transmissions of DWT-based encoded images and the impact of inserting application-specific information into the frame header. We believe that our discussions can contribute to the advance of the design of wireless image sensor networks.

关键词： Energy consumption Wireless sensor networks Wireless communication Payloads Discrete wavelet transforms Sensors Image sensors

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A semi-reliable energy-efficient retransmission mechanism based on the sensing relevancies of source nodes for wireless image sensor networks

A semi-reliable energy-efficient retransmission mechanism ba...

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International Symposium on Wireless Communication Systems (ISWCS)

作者： Daniel G. Costa Luiz Affonso Guedes Francisco Vasques Paulo Portugal Odilson T. Valle Department of Computing and Automation Federal University of Rio Grande do Norte Brazil IDMEC/ISR Faculty of Engineering University of Porta Portugal Department of Technology State University of Feira de Santana Brazil

Whenever reliable transmissions are assured by retransmission mechanisms, higher packet error incur in additional energy consumption due to packet retransmissions, even though many monitoring applications can tolerate some loss in the quality of the received images. In fact, visual information retrieved from source nodes may have different relevancies for the applications, according to the desired monitoring tasks and the current sensors' poses and fields of view. We propose a semi-reliable energy-efficient hop-by-hop retransmission mechanism, where the reliability level of each packet is function of the relevance of the source nodes associated with DWT subbands. Doing so, some of the corrupted packets will not be retransmitted, saving energy of intermediate nodes with low impact to the visual monitoring quality.

关键词： Energy consumption Discrete wavelet transforms Sensors Wireless sensor networks Monitoring Strontium Visualization

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QoV: Assessing the monitoring quality in visual sensor networks

QoV: Assessing the monitoring quality in visual sensor netwo...

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IEEE International Conference on Wireless and Mobile computing, Networking And Communications (WiMob)

Camera-enabled sensor nodes deployed for visual monitoring can considerably enlarge the applicability of wireless sensor networks. Due to the stringent requirements of visual data transmission and processing, when compared with scalar wireless sensor networks, quality assessment becomes a relevant issue. Although academic investigation has been focused on QoS parameters such as end-to-end delay, throughput and packet error rate, what is being seen by source nodes may be more important for the application than the quality of received data. In such way, we propose the novel concept of Quality of Viewing (QoV) to be employed as an important QoS parameter when assessing the monitoring quality in visual sensor networks. Some issues for the establishment of the QoV of monitoring applications will be presented, as well as practical exploitation of this parameter for dynamic verification, control and management of wireless sensor networks composed of camera-enabled source nodes.

关键词： Visualization Monitoring Quality of service Wireless sensor networks Measurement Sensors Quality assessment

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Fault-tolerant Control Design Based on Adaptive Dynamic Sliding Mode Technique for Near Space Vehicles

Fault-tolerant Control Design Based on Adaptive Dynamic Slid...

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The 24th Chinese Control and Decision Conference (第24届中国控制与决策学术年会 2012 CCDC)

作者： Bin Jiang Jing Zhao Xunhong lv Peng Shi College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 2100 Department of Computing and Mathematical Sciences University of Glamorgan Pontypridd CF37 1DL UK

In this paper, a novel adaptive dynamic sliding mode (ADSM) fault-tolerant control (FTC) methodology is developed for near space vehicle attitude control systems with actuator faults. The proposed ADSM approach which combines dynamic sliding mode with adaptive control strategies can make the systems stable and accurately track the desired signals in presence of external disturbances, model parameter uncertainties and even actuator faults. Firstly, the faulty attitude dynamic model of X-33 is introduced, and then the ADSM control and fault-tolerant control laws are designed for outer-loop and inner-loop respectively. Finally, simulation results are provided to show the effectiveness of the proposed FTC scheme.

关键词： Fault Tolerant Control Adaptive Dynamic Sliding Mode Near Space Vehicles

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$H_{\infty}$ Filtering for Discrete-Time Systems With Stochastic Incomplete Measurement and Mixed Delays

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IEEE Transactions on Industrial Electronics 2012年第6期59卷 2732-2739页

作者： Peng Shi Xiaoli Luan Fei Liu School of Engineering and Science Victoria University Melbourne VIC Australia Key Laboratory of Advanced Control for Light Industry Processes Ministry of Education Institute of Automation Jiangnan University Wuxi China Department of Computing and Mathematical Sciences University of Glamorgan Pontypridd UK

This paper focuses on the H ∞ filtering problem for a class of discrete-time systems with stochastic incomplete measurement and mixed random delays. A more realistic and accurate measurement mode is proposed to compensate for the negative influence of both missing data and different time delays in a random way. In the system, all of the stochastic variables are mutually independent but satisfy the Bernoulli binary distribution. In particular, the stochastic infinite distributed delays are introduced in the discrete-time domain. Sufficient conditions for the existence of the admissible filter are derived in terms of linear matrix inequalities, which ensures the asymptotic stability as well as a prescribed H ∞ performance for the filter errors. A simulation example is exploited to demonstrate the effectiveness of the proposed design procedures.

关键词： Discrete time systems Symmetric matrices Linear matrix inequalities Loss measurement Delay effects Distributed databases Stochastic processes Random processes

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Stability Analysis for High Frequency Networked Control Systems

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IEEE Transactions on Automatic Control 2012年第10期57卷 2694-2700页

作者： Hongjiu Yang Yuanqing Xia Peng Shi Mengyin Fu Institute of Electrical Engineering Yanshan University Qinhuangdao China School of Automation Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing Institute of Technology Beijing China School of Engineering and Science Victoria University Melbourne VIC Australia Department of Computing and Mathematical Sciences University of Glamorgan Pontypridd UK

This note generalizes the stability analysis for a high frequency networked control system. The high-frequency networked control system is described by a delta operator system with a high frequency constraint. Stability conditions are given for the high frequency delta operator system. Furthermore, by developing the generalized Kalman-Yakubovic-Popov lemma, improved stability conditions are also presented in terms of linear matrix inequalities. Some experiment results are presented to illustrate the effectiveness of the developed techniques.

关键词： Stability analysis Delay Linear matrix inequalities Frequency control Educational institutions Power system stability Numerical stability

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Recursive filtering for a class of nonlinear systems with missing measurements

Recursive filtering for a class of nonlinear systems with mi...

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2012 UKACC International Conference on Control, CONTROL 2012

作者： Hu, Jun Wang, Zidong Shen, Bo Cai, Chenxiao Lam, James Research Institute of Intelligent Control and Systems Harbin Institute of Technology Harbin 150001 China Department of Information Systems and Computing Brunel University London UB8 3PH United Kingdom Institute for Automatic Control and Complex Systems University of Duisburg-Essen D-47057 Duisburg Germany School of Automation Nanjing University of Science and Technology 210094 Nanjing China Department of Mechanical Engineering University of Hong Kong Hong Kong Hong Kong

ISBN: (纸本)9781467315609

This paper is concerned with the finite-horizon recursive filtering problem for a class of nonlinear time-varying systems with missing measurements. The missing measurements are modeled by a series of mutually independent random variables obeying Bernoulli distributions with possibly different occurrence probabilities. Attention is focused on the design of a recursive filter such that, for the missing measurements, an upper bound for the filtering error covariance is guaranteed and such an upper bound is subsequently minimized by properly designing the filter parameters at each sampling instant. The desired filter parameters are obtained by solving two Riccati-like difference equations that are of a recursive form suitable for online applications. A simulation example is exploited to demonstrate the effectiveness of the proposed filter design scheme. © 2012 IEEE.

关键词： Difference equations

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New Fault Detection Filter Design Approach for Continues-time Switched Systems

New Fault Detection Filter Design Approach for Continues-tim...

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American Control Conference

作者： Dongsheng Du Bin Jiang Peng Shi Hamid Reza Karimi College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 Jiangsu P.R. China Department of Computing and Mathematical Sciences University of Glamorgan Pontypridd CF37 1DL UK Department of Engineering Faculty of Engineering and Science University of Agder N-4898 Grimstad Norway

ISBN: (纸本)9781457710957

This paper investigates the problem of fault detection filter design for continuous-time switched systems. The designed fault detection filter is assumed to be asynchronous with the original systems. Attention is focused on designing a fault detection filter such that the estimation error between the residual and the fault is minimized in the sense of H_∞ norm. By employing piecewise Lyapunov function and average dwell time techniques, a sufficient condition for the existence of such a filter is exploited in terms of certain linear matrix inequalities. Finally, an example is provided to illustrate the effectiveness of the proposed approach.

关键词： Fault detection filter Switched systems Liapunov function Asynchronous design approach Filters

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Design of Large Synchronous Turbo-Generator Monitoring System

Design of Large Synchronous Turbo-Generator Monitoring Syste...

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International Conference on Electrical Machines

作者： Marinko Kovacic Zlatko Hanic Mario Vrazic the Department of Electric Machines Drives and Automation Faculty of Electrical Engineering and Computing University of Zagreb Croatia

ISBN: (纸本)9781467301435

This paper presents an approach to design of synchronous turbo generator monitoring system. Various physical quantities that are important for operation of the synchronous generator in the power plant such as armature and field voltages and currents, position of the rotor, vibrations of the end windings, flux densities and temperatures over machine are monitored. Paper describes transducers that were used, data acquisition hardware as well as developed data acquisition, visualization and monitoring application with the abilities of recording trends of calculated quantities and waveforms of captured transients. Described measurement system is installed in the thermal power plant on the 247 MVA 3000 rpm synchronous generator and is currently in continuous operation for 9 months.

关键词： Condition monitoring Data acquisition Generator Vibration measurement

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Biophotogrammetry model of respiratory motion analysis applied to children

Biophotogrammetry model of respiratory motion analysis appli...

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Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： W. L. Ripka D. da V. Ricieri L. Ulbricht E. B. Neves A. M. W Stadnik E. F. R. Romaneli Electrical Engineering and Industrial Computing Program Federal University of Technology Paraná Brazil Physical Education Department Federal University of Paraná Brazil Master Program in Biomedical Engineering Physical Education Federal University of Technology Paraná Brazil Control and Automation Engineering Federal University of Technology Paraná Brazil

This study aimed to test a protocol of measurements based on Biophotogrammetry to Analysis of Respiratory Mechanics (BARM) in healthy children. Seventeen normal spirometric children (six male and 11 female) were tested. Their performed maneuvers of forced inspiratory vital capacity were recorded in the supine position. The images were acquired by a digital camera, laterally placed to the trunk. Surface markers allowed that the files, exported to CorelDraw® software, were processed by irregular trapezoids paths. Compartments were defined in the thoracic (TX), abdominal (AB) and the chest wall (CW). They were defined at the end of an inspiration and expiration, both maximum, controlled by a digital spirometer. The result showed that the measured areas at the inspiratory and expiratory periods were statistically different (p

关键词： Muscles Educational institutions Lungs Member and Geographic Activities Board committees Biological system modeling Pediatrics Surface treatment

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