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State feedback stabilization of discrete linear switching systems subject to nonsymmetrical state and control bounds

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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, harbin institute of technology, harbin 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

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,harbin institute of technology, harbin 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

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

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

UNSTEADY SUPERCAVITATING FLOW PAST CONES

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 harbin institute of technology harbin china department. of control science and engineering harbin institute of technology harbin 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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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

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,harbin institute of technology,harbin 150001,china 3 department of engineering,Northeast Agricultural University,harbin 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

Microstructure of a Mo-Si-C-N multi-layered anti-oxidation coating on carbon/carbon composites by fused slurry

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Rare Metals 2009年第5期28卷 460-464页

作者： LAI Zhonghong MENG Songhe ZHU Jingchuan JEON Jaeho School of Materials science and engineering Harbin Institute of Technology Harbin 150001 China Research Center for Composite Materials Harbin Institute of Technology Harbin 150001 China department of Materials technology Korea Institute of Machinery ＆ Materials Changwon 641-010 Korea

A Mo-Si-C-N multi-layered anti-oxidation coating was in-situ fabricated by introducing nitrogen atmosphere during the fused sintering of Mo-Si slurry pre-layer on carbon/carbon composites. The phase composition and microstructure of the Mo-Si-C-N coating were characterized by X-ray diffractometry, optical microscopy, scanning electron microscopy with energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. The Mo-Si-C-N coating exhibited a three-layered structure. Besides the MoSi2/Si main-layer and the SiC bonding-layer, a surface layer of about 10 μm in thickness was synthesized on the coating surface. The surface layer mainly consisted of SiC nanowires and contained some Si3N4 and Si phases. SiC nanowires of 10 to 200 nm in diameter presented a terrace and distortion structure. Transmission electron microscopy indicated that the SiC nanowires grew along the preferred 〈111〉 direction. During oxidation test, SiC nanowires transmuted into SiO2 glass, which can play an important role in improving the oxidation resistance of C/C composites.

关键词： C/C composites coating microstructures anti-oxidation

Cell cycle-dependent gene networks relevant to cancer

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Progress in Natural science:Materials International 2008年第8期18卷 945-952页

作者： Yun Xiao a,1, Xia Lia,b,*,1, Yueying Yang a, Yadong Wangc, Shaoqi Rao a,b a College of Bioinformatics science and technology, and Bio-pharmaceutical Key Laboratory of heilongjiang Province and State, harbin Medical University, harbin 150086, china b Biomedical engineering institute of Capital Medical University, Beijing 10004, china c department of Computer science, harbin institute of technology, harbin 150080, china College of Bioinformatics science and technology and Bio-pharmaceutical Key Laboratory of Heilongjiang Province and State Harbin Medical University Harbin 150086 China Biomedical engineering institute of Capital Medical University Beijing 10004 China department of Computer science Harbin Institute of Technology Harbin 150080 China

The analysis of sophisticated interplays between cell cycle-dependent genes in a disease condition is one of the largely unexplored areas in modern tumor biology research. Many cell cycle-dependent genes are either oncogenes or suppressor genes, or are closely associated with the transition of a cell cycle. However, it is unclear how the complicated relationships between these cell cycle-dependent genes are, especially in cancers. Here, we sought to identify significant expression relationships between cell cycle-dependent genes by analyzing a HeLa microarray dataset using a local alignment algorithm and constructed a gene transcriptional network specific to the cancer by assembling these newly identified gene-gene relationships. We further characterized this global network by partitioning the whole network into several cell cycle phase-specific sub-networks. All generated networks exhibited the power-law node-degree distribution, and the average clustering coefficients of these networks were remarkably higher than those of pure scale-free networks, indicating a property of hierarchical modularity. Based on the known protein-protein interactions and Gene Ontology annotation data, the proteins encoded by cell cycle-dependent interacting genes tended to share the same biological functions or to be involved in the same biological processes, rather than interacting by physical means. Finally, we identified the hub genes related to cancer based on the topological importance that maintain the basic structure of cell cycle-dependent gene networks.

关键词： Cell cycle Microarray HeLa cell Gene network

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, harbin institute of technology, harbin heilongjiang 150001, china 2.department of Mathematics, harbin institute of technology, harbin 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

Novel Harmonic Free Single Phase Variable Inductor Based on Active Power Filter Strategy

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Novel Harmonic Free Single Phase Variable Inductor Based on ...