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控制理论与应用（英文版） 2012年第2期10卷 216-222页

作者： Zhiyuan LIU 1 , Guowei FAN 1 , Hong CHEN 2 1.department of control science and engineering, har.in institute of technology, har.in heilongjiang 150001, china 2.department of control science and engineering, Jilin University, Changchun Jilin 130025, china department of control science and engineering Harbin Institute of Technology Harbin Heilongjiang China department of control science and engineering Jilin University Changchun Jilin China

Stabilization problem of discrete-time linear switching systems with bounds on the state and control input is solved in this paper. First, the synthesis of state feedback controllers that ensure the stability of closed-loop switching systems is studied under a sufficient condition. By using the idea of positive invariance, a stabilizing controller design methodology is proposed. Based on these results, the convergence rate problem is also discussed. A state feedback controller that guarantees the optimal convergence rate of closed-loop switching systems is obtained via optimization. Finally, an example made up of two subsystems is studied to show the application of our method.

关键词： Switching systems Constraints Stabilization problem Convergence rate problem

Robust observer-based control for uncertain discrete-time piecewise affine systems

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控制理论与应用（英文版） 2012年第2期10卷 236-243页

作者： Yahui GAO 1 , Zhiyuan LIU 2 , Hong CHEN 3 1.AVIC (Aviation Industry Corporation of china) china Aviation Motor control System institute, Wuxi Jiangsu 214063, china 2.department of control science and engineering, har.in institute of technology, har.in heilongjiang 150001, china 3.department of control science and engineering, Jilin University, Changchun Jilin 130025, china AVIC (Aviation Industry Corporation of china) china Aviation Motor control System institute Wuxi Jiangsu China department of control science and engineering Harbin Institute of Technology Harbin Heilongjiang China department of control science and engineering Jilin University Changchun Jilin China

The main contribution of this paper is to present a novel robust observer-based controller design method for discrete-time piecewise affine systems with norm-bounded uncertainties. The key ideas are to construct a piecewise quadratic Lyapunov function to guarantee the stability of the closed-loop systems, approximate polytopic operating regions by ellipsoids, and use the singular value decomposition technique to treat the constraint of matrix equality. It is shown that the suggested control method can be formulated as linear matrix inequalities that are numerically feasible with commer- cially available software. A numerical example is also given to verify the proposed approach.

关键词： Piecewise affine systems Robust control Observer Linear matrix inequality

Generalized Self-Adaptive Genetic Algorithms

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 72-75页

作者： Bin Wu Xuyan Tu Jian Wu Information engineering School, University of science and technology Beijing, Beijing 100083, china department of Information and control engineering, Southwest institute of technology, Mianyang 621002, china Information engineering School University of Science and Technology Beijing Beijing 100083 China department of Information and control engineering Southwest Institute of Technology Mianyang 621002 China

In order to solve the problem between searching performance and convergence of genetic algorithms, a fast genetic algorithm generalized self-adaptive genetic algorithm (GSAGA) is presented. (1) Evenly distributed initial population is generated. (2) Superior individuals are not broken because of crossover and mutation operation for they are sent to subgeneration directly. (3) High quality im- migrants are introduced according to the condition of the population schema. (4) Crossover and mutation are operated on self-adaptation. Therefore, GSAGA solves the coordination problem between convergence and searching performance. In GSAGA, the searching per- formance and global convergence are greatly improved compared with many existing genetic algorithms. Through simulation, the val- idity of this modified genetic algorithm is proved.

关键词： generalized self-adaptive genetic algorithm initial population immigration fitness function

V_2O_5/C catalyst for liquid phase oxidation of glyoxal to glyoxylic acid

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science china Chemistry 2009年第7期52卷 1057-1062页

作者： NIU YuLan1,2 & LI RuiFeng1 1 Key Laboratory of Coal science and technology, Ministry of Education, institute of Special Chemicals, Taiyuan University of technology, Taiyuan 030024, china 2.department of Chemical engineering, Taiyuan institute of technology, Taiyuan 030008, china Key Laboratory of Coal science and technology Ministry of Education Institute of Special Chemicals Taiyuan University of Technology Taiyuan 030024 China department of Chemical engineering Taiyuan Institute of Technology Taiyuan 030008 China

A study of the catalytic activity of V2O5/C catalyst for the oxygen oxidation of glyoxal has been made, showing that glyoxylic acid can be formed without control of pH value and there is little oxalic acid from the excessive oxidation of glyoxylic acid. The studies of XRD and TEM have shown that V2O5 diffraction peaks gradually strengthen with the increase of the content of V2O5. With the content of 3% V2O5 and the calcination temperature of 573 K, V2O5/C catalyst displayed the best activity and selectivity. The conversion of glyoxal and the selectivity of glyoxylic acid reached 18.76% and 77.70% after 5 h, respectively. Moreover, V2O5/C catalyst showed small deactivation after recycling three times, which indicates that V2O5/C has a higher stability than noble metal catalysts in the reaction medium.

关键词： glyoxal glyoxylic acid V2O5/C catalyst

Neural integrated control for a free-floating space robot with suddenly changing parameters

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science china(Information sciences) 2011年第10期54卷 2091-2099页

作者： ZHANG WenHui 1,2 ,QI NaiMing 2,MA Jing 1,3 & XIAO AYang 2 1 School of Electromechanical engineering,Xuzhou Normal University,Xuzhou 221116,china 2 School of Aerospace,har.in institute of technology,har.in 150001,china 3 department of engineering,Northeast Agricultural University,har.in 150001,china 1. School of Electromechanical engineering Xuzhou Normal University Xuzhou 221116 China2. School of Aerospace Harbin Institute of Technology Harbin 150001 China3. Department of Engineering Northeast Agricultural University Harbin 150001 China

Because the state of a free-floating space robot model is uncertain and sudden changes in the model parameters might undermine the stability of the system,this paper proposes a control strategy based on a variable structure neural integrated *** scheme does not need a precise space robot model,making use of the radial basis function neural network ability approach to learn about an uncertain *** network weights are adjusted online in *** the early period of the control phase and parameter changes,the variable structure controller compensates for the uncertain model which the neural network could not learn *** also creates global asymptotic stability for the whole closed-loop *** results show that the controller can handle bad changeable conditions and has important application value for defense,aerospace and other major security fields.

关键词： neural network variable structure adaptive control global asymptotical stability

RESEARCH ON THE MINIMUM ZONE CYLINDRICITY EVALUATION BASED ON GENETIC ALGORITHMS

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Chinese Journal of Mechanical engineering 2003年第2期16卷 167-170页

作者： Cui ChangcaiChe RenshengYe DongHuang Qingchengdepartment of Automatic Measurement and control,har.in institute of technology, har.in 150001, china department of Automatic Measurement and control Harbin Institute of Technology Harbin 150001 China

A genetic algorithm (GA)-based method is proposed to solve the nonlinearoptimization problem of minimum zone cylindricity evaluation. First, the background of the problemis introduced. Then the mathematical model and the fitness function are derived from themathematical definition of dimensioning and tolerancing principles. Thirdly with the least squaressolution as the initial values, the whole implementation process of the algorithm is realized inwhich some key techniques, for example, variables representing, population initializing and suchbasic operations as selection, crossover and mutation, are discussed in detail. Finally, examplesare quoted to verify the proposed algorithm. The computation results indicate that the GA-basedoptimization method performs well on cylindricity evaluation. The outstanding advantages concludehigh accuracy, high efficiency and capabilities of solving complicated nonlinear and large spaceproblems.

关键词： genetic algorithm (GA) cylindricity form error minimum zone

Robust model-reference control for descriptor linear systems subject to parameter uncertainties

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control Theory and technology 2007年第3期 213-220页

作者： Guangren DUAN 1, Biao ZHANG 1,2 (1.Center for control Theory and Guidance technology, har.in institute of technology, har.in heilongjiang 150001, china 2.department of Mathematics, har.in institute of technology, har.in heilongjiang 150001, china)

Robust model-reference control for descriptor linear systems with structural parameter uncertainties is investigated. A sufficient condition for existing a model-reference zero-error asymptotic tracking controller is given. It is shown that the robust model reference control problem can be decomposed into two subproblems: a robust state feedback stabilization problem for descriptor systems subject to parameter uncertainties and a robust compensation problem. The latter aims to find three coefficient matrices which satisfy four matrix equations and simultaneously minimize the effect of the uncertainties to the tracking error. Based on a complete parametric solution to a class of generalized Sylvester matrix equations, the robust compensation problem is converted into a minimization problem with quadratic cost and linear constraints. A numerical example shows the effect of the proposed approach.

关键词： Descriptor linear systems Model-reference control Parameter uncertainties Robust stabilization Robust compensation

Feasibility Analysis of Accelerometer Configuration of Non-gyro Micro Inertial Measurement Unit

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Feasibility Analysis of Accelerometer Configuration of Non-g...

Robust integral sliding mode control for uncertain systems with multiple time delays

CES/IEEE 5th International Power Electronics and Motion control Conference

作者： DING Mingli ZHOU Qingdong WANG Qi and WANG Changhong department. of Automatic Test and control har.in institute of technology har.in china department. of control science and engineering har.in institute of technology har.in china department of Automatic Test and control Harbin Institute of Technology Harbin China department of control science and engineering Harbin Institute of Technology Harbin China

ISBN: (纸本)1424404487;9781424404483

＜正＞A sufficient condition is given to determine if a configuration of accelerometers of non-gyro micro inertial measurement unit （NGMIMU） is feasible. NGMIMU uses only accelerometers to compute the motion of a moving body. If the condition is satisfied, the angular acceleration and the linear acceleration in three directions can be expressed by the linear combination of the angular velocity and the accelerometer output. And the posture of a moving body can be estimated using a numerical iteration algorithm. Two configurations of accelerometers are analyzed in detail and the results verify the correctness of the condition. This research serves as an important criterion for the research of other problems of NGMIMU.

关键词： Measurement Unti Accelerometer Feasibility Configuration

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控制理论与应用（英文版） 2010年第2期8卷 211-214页

作者： Xiaoyu ZHANG, Xiangna LI (department of Electronic and Information engineering, North china institute of science and technology, Beijing 101601, china) department of Electronic and Information engineering North China Institute of Science and Technology Beijing China

This paper proposes a robust integral sliding mode (RISM) manifold and the corresponding stabilization control law for uncertain systems with multiple time-varying time delays based on the techniques of linear matrix inequalities (LMI). The sufficient condition for the existence of the RISM manifold is given in terms of LMI, and then, the sliding mode control (SMC) law that can keep the system state on the RISM manifold from the initial time moment is developed. The efficiency and feasibility of the results are illustrated by a numerical example.

关键词： Robust control Integral sliding mode Time-delay systems LMI

UNSTEADY SUPERCAVITATING FLOW PAST CONES

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Journal of Hydrodynamics 2006年第3期18卷 262-272页

作者： HU Chao YANG Hong-lan ZHAO Cun-bao HUANG Wen-hu institute of Aerospace engineering and Applied mechanics Tongji Universtity Shanghai 200092 China department of Aerospace engineering and Mechanics Harbin Institute of Technology Harbin 150001 China department of Aerospace engineering and Mechanics Harbin Institute of Technology Harbin 150001 China

Based on integral equation method, the study of unsteady supercavitating flow past cones is presented. The shape and length of supercavity are calculated respectively using the finite difference time discretization method. The characteristics of the shape and length of supercavities, which vary with the cone＇s angle and cavitation number, are investigated respectively, the varied features of some supercavity scales are analyzed when the flow field is perturbed periodically. The curves relationship between cavity length and cavitation number, which are based respectively on present method and other theories, are discussed and compared. It is obviously shown that the supercavity changes have two characteristics： retardance and wave. These results obtained would be useful in the case of design and analysis of cavitator under water.

关键词： supercavitation cavitator unsteady flow,slender body theory integral equation method