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第23届过程控制会议

作者： Jingjing Du Wei Qian Chunyue Song School of Electrical Engineering and Automation Henan Polytechnic University Jiaozuo 454000 State Key Lab. of Industrial Control Technology Institute of Industrial Process Control Zhejiang U

A gridding algorithm based on gap metric is proposed for multimodel control of nonlinear systems. In contrast to the common evenly distributed gridding algorithm used in multimodel decomposition, the proposed gap metric based gridding algorithm aims to reduce reliance on previous knowledge and experience and makes the gridding more systematic and more reasonable. Based on the proposed gridding algorithm, an improved integrated multimodel H∞ loop-shaping control is developed, which realizes information symmetry between local linear model selection and local controller design, and raises the efficiency of multimodel controller design largely.

关键词： Gap metric Gridding Integrated Multimodel control H∞ loop-shaping control.

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Analysis of cutoff frequency in trapezoid tunnel using edge element method

Analysis of cutoff frequency in trapezoid tunnel using edge ...

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2012 International Conference on Microwave and Millimeter Wave Technology, ICMMT 2012

作者： Zhang, Chuanlei Luo, Ji'an Zhang, Shanwen Sun, Jiping Department of Electrical and Computer Engineering Ryerson University Toronto ON M5B 2K3 Canada State Key Lab. of Industrial Control Tech. Zhejiang University Zhejiang 310027 China Department of Engineering and Technology Zhengzhou University Zhengzhou 451150 China D11 Xueyuan Road Haidian District Beijing 100083 China

ISBN: (纸本)9781467321839

The effect of cross section dimension in trapezoid tunnel on cutoff frequency is analyzed with edge element method. The variation of cutoff frequency in trapezoid tunnel with top side, bottom side and height changes are found, respectively. It comes to a useful conclusion that the cutoff frequency of trapezoid tunnel is determined by the larger one of tunnel's height and the average of tunnel's top side and tunnel's bottom side. A simple equivalent formula is given to calculate the dominant mode cutoff frequency in trapezoid waveguide. Computation results are presented to show the validity and the accuracy of the equivalent method. © 2012 IEEE.

关键词： Cutoff frequency

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Energy-efficient intrusion detection with a barrier of probabilistic sensors

Energy-efficient intrusion detection with a barrier of proba...

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IEEE Annual Joint Conference: INFOCOM, IEEE computer and Communications Societies

作者： Junkun Li Jiming Chen Ten H. Lai State Key Laboratory of Industrial Control Technology University of Zhejiang China Department of Computer Science and Engineering Ohio State Uinversity USA

ISBN: (纸本)9781467307734

Intrusion detection is a significant application in wireless sensor networks (WSNs). S. Kumar et al have introduced the concept of barrier coverage, which deploys sensors in a narrow belt region to guarantee that any intrusion across the region is to be detected. However, the practical issues have not been investigated such as scheduling sensors energy-efficiently while guaranteeing the detection probability of any intrusion across the region based on probabilistic sensing model, which is a more realistic sensing model. Besides, the intruders may be humans, animals, fighter planes or other things, which obviously have diverse moving speeds. In this paper, we analyze the detection probability of arbitrary path across the barrier of sensors theoretically and take the maximum speed of possible intruders into consideration since the sensor networks are designed for different intruders in different scenarios. Based on the theoretical analysis of detection probability, we formulate a Minimum Weight ∈-Barrier Problem about how to schedule sensors energy-efficiently. We show the problem NP-hard and propose a bounded approximation algorithm, called Minimum Weight Barrier Algorithm (MWBA) to schedule the activation of sensors. To evaluate our design, we analyze the performance of MWBA theoretically and also perform extensive simulations to demonstrate the effectiveness of our proposed algorithm.

关键词： Wireless sensor networks Probabilistic logic Belts Sensor phenomena and characterization Image edge detection Algorithm design and analysis

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Study on modeling and stability analysis of nonlinear transmission system of wind turbine generator system

Study on modeling and stability analysis of nonlinear transm...

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第23届过程控制会议

作者： Meng Zong Fu Liyuan Song Minghou Key Laboratory of Measurement Technology and Instrumentation of Hebei Province Yanshan University Key Laboratory of Industrial Computer Control Engineering of Hebei Province Yanshan University Qin

The nonlinear dynamical model of wind turbine generator drive system is presented considering nonlinear stiffness of the drive system. The frequency characteristics of wind turbine drive system incented by different forms, such as phase plane and Poincaré section are studied by simulation. The stability of wind turbine generator drive system is analyzed by using bifurcation and chaos theories. The stability of the periodic motion and the process of period-doubling bifurcation into chaos are further studied, and the effect of nonlinear stiffness on stability of wind turbine generator drive system is showed. The results show that negative nonlinear stiffness is beneficial to keep the stability of system, and when the chaos appears on the system, incentive parameter increases as the negative nonlinear stiffness increases.

关键词： Wind turbine generator system Drive system Dynamical model Nonlinear stiffness Bifurcation and chaos

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Robust nonlinear model predictive control algorithm based on reduced precision solution criteria

Robust nonlinear model predictive control algorithm based on...

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World Congress on Intelligent control and Automation (WCICA)

作者： Jiaona Wan Tiejun Zhang Kexin Wang Xueyi Fang Zhijiang Shao Research Institute of Highway Ministry of Transport Beijing 100088 China State Key Lab. of Industrial Control Technology Institute of Industrial Control Department of Control Science and Engineering Zhejiang University Hangzhou 310027 China

This paper discusses the robustness of nonlinear model predictive control (NMPC) based on sub-optimal solution obtained under reduced precision solution (RPS) criteria. NMPC needs to solve the optimal control problem (OCP) quickly and the input is injected to the controlled plant in time. Traditional convergence criteria in optimization algorithms usually cost excessive long computation time with little improvement of solution, which results in degradation of control performance eventually. RPS criteria are new convergence criteria for deciding whether the current iterate is good enough and whether the optimization procedure should be terminated. It can terminate the optimization process timely. This work pays special attention to robustness of the closed-loop system controlled by NMPC with RPS criteria when model plant mismatch exists. Simulations demonstrate that the proposed algorithm owns good robustness and stability.

关键词： Optimization Delay Mathematical model Computational modeling Convergence Robustness Asymptotic stability

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Study on parameter selection of phase space reconstruction for chaotic time series

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Advances in Information Sciences and Service Sciences 2012年第2期4卷 67-77页

作者： Zhang, Wenyuan Ma, Yunfei Yang, Gang Department of Computer EandA College Hebei Normal University of Science and Technology Qinhuangdao 066004 Hebei China Key Laboratory of Hebei Province Industrial Computer Control Engineering Institute of Electrical Engineering Yanshan University Qinhuangdao 066004 Hebei Province China

Based on the principle that the selection of delay time and embedding dimension has no correlation in the process of phase space reconstruction, this paper puts forward a new method of identifying the embedding dimension by Cao Liangyue Theory (CAO Theory) after the delay time is identified by Mutual Information Function. By means of the numerical verification of a few typical examples of chaotic dynamic system, the result shows that the method can identify the valid delay time of phase space reconstruction and the best embedding dimension. In addition, a new way of identifying the chaotic signal is provided and this method can effectively reconstruct the phase space of the original system from the time series.

关键词： Time series

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Introduction to time series search engine systems

Introduction to time series search engine systems

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International Conference on Systems and Informatics (ICSAI)

作者： Chuanlei Zhang Ji'an Luo Shanwen Zhang Chen Zhang Department of Electrical & Computer Engineering Ryerson University State Key Lab. of Industrial Control Tech. Zhejiang University Zhejiang China Department of Engineering and Technology Zhengzhou University China Discover Information Technology Limited Shanghai China

Basic structure of time series search engine system, involving acquisition, data processing and retrieval sub-systems, was elaborated. And options for time series search engine architectures and supported features and... 详细信息

关键词： Time series analysis Data mining Search engines Feature extraction Interpolation Data processing Indexing

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A NoSQL based cached storage solution of GIS Web service

International Journal of Digital Content Technology and its ...

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International Journal of Digital Content Technology and its Applications 2012年第20期6卷 268-276页

作者： Liu, Jin Wu, Yangping Zhuo, Dan Hu, Qiping Wang, Yan Zhang, Wensheng State Key Lab of Software Engineering Computer School Wuhan University China International School of Software Wuhan University China State Key Lab of Management and Control for Complex Systems Institute of Automation Chinese Academy of Science China

One of challenges in GIS Web service is mass GIS data storage and processing. There are at least three obstacles that oppose dealing with this challenge: the mismatch between the frequent requirement of concurrent tasks for accessing data in GIS Web service and the poor performance of conventional storage mechanism such as relational databases;the insufficiency of relational databases to manage complex data types in GIS Web service;the horizontal scalability of storage for non-stop GIS Web service evolution. This paper proposes a distributed cached storage solution, as the mixture of MongoDB storage and Memcached cache, for GIS Web service. Both techniques are closely related to NoSQL that is a class of database management system identified by its non-adherence to the widely used relational database management system (RDBMS) model. A concise case that facilitates a better understanding of this work indicates its feasibility.

关键词： Websites

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Multi-loop adaptive internal model control based on a dynamic partial least squares model

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2011年第3期12卷 190-200页

作者： Zhao ZHAO Bin HU Jun LIANG State Key Lab of Industrial Control Technology Department of Control Seienee & Engineering Zhejiang University Hangzhou 310027 China

A multi-loop adaptive internal model control (IMC) strategy based on a dynamic partial least squares (PLS) frame-work is proposed to account for plant model errors caused by slow aging,drift in operational conditions,or environmental *** PLS decomposition structure enables multi-loop controller design within latent spaces,a multivariable adaptive control scheme can be converted easily into several independent univariable control loops in the PLS *** each latent subspace,once the model error exceeds a specific threshold,online adaptation rules are implemented separately to correct the plant model mismatch via a recursive least squares (RLS) *** the IMC extracts the inverse of the minimum part of the internal model as its structure,the IMC controller is self-tuned by explicitly updating the parameters,which are parts of the internal *** parameter convergence and system stability are briefly analyzed,and proved to be ***,the proposed control scheme is tested and evaluated using a widely-used benchmark of a multi-input multi-output (MIMO) system with pure delay.

关键词： Partial least squares (PLS) Adaptive internal model control (IMC) Recursive least squares (RLS)

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Reduced precision solution criteria for nonlinear model predictive control with the feasibility-perturbed sequential quadratic programming algorithm

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Journal of Zhejiang University-Science C(computers and Electronics) 2011年第11期12卷 919-931页

作者： Jiao-na WAN Zhi-jiang SHAO Ke-xin WAN Xue-yi FANG Zhi-qiang WANG Ji-xin QIAN State Key Lab of Industrial Control Technology Institute of Industrial Control Department of Control Science and Engineering Zhejiang University Hangzhou 310027 China

We propose a novel kind of termination criteria, reduced precision solution (RPS) criteria, for solving optimal control problems (OCPs) in nonlinear model predictive control (NMPC), which should be solved quickly for new inputs to be applied in time. Computational delay, which may destroy the closed-loop stability, usually arises while non-convex and nonlinear OCPs are solved with differential equations as the constraints. Traditional termination criteria of optimization algorithms usually involve slow convergence in the solution procedure and waste computing resources. Considering the practical demand of solution precision, RPS criteria are developed to obtain good approximate solutions with less computational cost. These include some indices to judge the degree of convergence during the optimization procedure and can stop iterating in a timely way when there is no apparent improvement of the solution. To guarantee the feasibility of iterate for the solution procedure to be terminated early, the feasibility- perturbed sequential quadratic programming (FP-SQP) algorithm is used. Simulations on the reference tracking performance of a continuously stirred tank reactor (CSTR) show that the RPS criteria efficiently reduce computation time and the adverse effect of computational delay on closed-loop stability.

关键词： Nonlinear model predictive control （NMPC） Computational delay Termination criteria Continuously stirred tankreactor （CSTR）

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