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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

On characteristic modeling of a class of flight vehicles'attitude dynamics

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Science china(Technological Sciences) 2010年第8期53卷 2074-2080页

作者： MENG Bin &WU HongXin National Laboratory of Space Intelligent control,Beijing institute of control engineering,Beijing 100190,china National Laboratory of Space Intelligent control Beijing Institute of Control Engineering Beijing China

The characteristic modeling problem of flight vehicles'attitude dynamics is considered in this *** terms of the affine nonlinear system with triangle form of flight vehicles'attitude dynamics,a general method is presented to compress the dynamics into the characteristic model parameters,by introducing the time scale of nonlinear systems and a class of system states related compress *** parameter region and limit of the characteristic model are also *** the given parameter region it is seen that the bound of the characteristic model parameters is dependent on the sampling period,the modeling error,the system order and the system change *** modeling error of the established characteristic model can be arbitrarily small according to the control precision,showing the difference between the characteristic model and other model reduction methods,that is,no system information is lost using this *** the basis of this modeling approach,the characteristic model of the flexible satellite attitude is established,as well as the bound and limit of the parameters,which sets a theoretical foundation for characteristic model based control design of flight vehicles.

关键词： characteristic modeling modeling error time scale of nonlinear systems spacecraft attitude dynamics

A Novel Stable clustering Design Method for Hierarchical Satellite Network

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chinese Journal of Aeronautics 2010年第1期23卷 91-102页

作者： Zhou Mu,Guo Qing,Wang Zhenyong communication Research center,School of Electronics and information engineering,Harbin institute of Technology,Harbin 150001,china communication Research center School of Electronics and Information Engineering Harbin Institute of Technology Harbin 150001 China

This article proposes a novel stable clustering design method for hierarchical satellite network in order to increase its stability,reduce the overhead of storage and exert effective control of the delay performances based on a 5-dimensional vector model. According to the function of stability measureinent and owing to the limitation of minimal average routing table length, the hierarchical satellite network is grouped into separate stable connected clusters to improve destruction resistance and reconstruction ability in the future integrated network. In each cluster, redundant communication links with little contribution to network stability and slight influences on delay variation are deleted to satisfy the requirements for stability and connectivity by means of optimal link resources, and, also, the idea of logical weight is introduced to select the optimal satellites used to communicate with neighboring cluster satellites. Finally, the feasibility and effectiveness of the proposed method are verified by comparing it with the simulated performances of other two typical hierarchical satellite networks, double layer satellite constellation（DLSc） and satellite over satellite（SOS）.

关键词： satellite network hierarchical structure stability analysis clustering algorithms vector measurements

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

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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

On Robust Stability of a class of Uncertain Nonlinear Systems with Time-Varying Delay

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Systems Science and Systems engineering 2002年第2期11卷 129-135页

作者： NIAN Xiao-hongDepartment of Mechanics and engineering Sciences, Peking University,Beijing 100871 , china institute of information and control engineering,central South University, changsha 410075, china Department of Mechanics and engineering Sciences Peking UniversityBeijing 100871 China institute of information and control engineering Central South University Changsha 410075 China

The problem of robust stability of a class of uncertain nonlinear dynamical systems with time-delay is considered. Based on the assumption that the nominal system is stable, some sufficient conditions on robust stability of uncertain nonlinear dynamical systems with time-delay are derived. Some analytical methods and a type of Lyapunov functional are used to investigate such sufficient conditions. The results obtained in this paper are applicable to perturbed time-delay systems with unbounded time-varying delay. Some previous results are improved and a numerical example is given to demonstrate the validity of our results.

关键词： robust stability nonlinear time-delay uncertainty

Stability analysis of a hypersonic vehicle controlled by the characteristic model based adaptive controller

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Science china(information Sciences) 2012年第10期55卷 2243-2256页

作者： ZHANG Zhao 1,2 & HU Jun 1 1 Beijing institute of control engineering,Beijing 100190,china 2 Science and Technology on Space Intelligent control Laboratory,Beijing 100190,china Beijing institute of control engineering Beijing China Science and Technology on Space Intelligent control Laboratory Beijing China

The closed loop attitude stability of a hypersonic vehicle controlled by the characteristic model-based all-coefficient adaptive controller is studied in this paper,and an algorithm based on the computation of induced matrix 1-norm or ∞-norm is *** of all,the Taylor series expansion is applied to discretize the inputoutput description of the attitude dynamics of the *** obtained difference equations have the same structure as characteristic model;thus the intervals which contain all possible values of certain characteristic model parameters are *** the linear feedback controller is used in the feedback loop,with some conservation,the closed loop system is viewed as a class of interval time-varying systems defined by a number of free time-varying *** free parameters take values from predefined *** sufficient and necessary condition for the stability of this class of system is ***,a sufficient condition for the stability of hypersonic vehicle attitude control loop is proposed and demonstration example is *** method proposed checks up the stability of the closed loop system by evaluating a finite number of matrix norms,and overcomes the difficulties brought by the time-varying nature of the characteristic model and parameter estimation.

关键词： characteristic model hypersonic vehicle interval time-varying system stability test attitude control

An output delay approach to fault estimation for sampled-data systems

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Science china(information Sciences) 2012年第9期55卷 2128-2138页

作者： WEN chengLin 1,QIU AiBing 2 & JIANG Bin 3 1 institute of information and control,Hangzhou Dianzi University,Hangzhou 310018,china 2 School of Electrical engineering,Nantong University,Nantong 226019,china 3 college of Automation engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,china institute of information and control Hangzhou Dianzi University Hangzhou China School of Electrical engineering Nantong University Nantong China college of Automation engineering Nanjing University of Aeronautics and Astronautics Nanjing China

The problem of fault estimation for a class of non-uniformly sampled-data systems is investigated from the time delay point of view in this ***,the output delay approach is employed to model the sampled-data system as a continuous-time one with time-varying delay ***,based on the analysis of the inapplicability of the adaptive fault diagnosis observer in such class of time-delay systems,a novel augmented fault estimation observer design method is proposed to guarantee the exponential convergence of the estimation ***,an extension to the case of time varying fault estimation for the noisy sampled-data systems is ***,simulation results of a flight control system are presented to demonstrate the effectiveness of the proposed method.

关键词： fault estimation non-uniformly sampled-data augmented observer output delay

Revision of seismic design codes corresponding to building damagesin the “5.12” Wenchuan earthquake

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Earthquake engineering and engineering Vibration 2010年第2期9卷 147-155页

作者： Wang Yayong institute of Earthquake engineering, china Academy of Building Research, Beijing 100013, china institute of Earthquake engineering China Academy of Building Research Beijing China

A large number of buildings were seriously damaged or collapsed in the "5.12" Wenchuan earthquake. Based on field surveys and studies of damage to different types of buildings, seismic design codes have been updated. This paper briefly summarizes some of the major revisions that have been incorporated into the "Standard for classification of seismic protection of building constructions GB50223-2008" and "code for Seismic Design of Buildings GB50011-2001." The definition of seismic fortification class for buildings has been revisited, and as a result, the seismic classifications for schools, hospitals and other buildings that hold large populations such as evacuation shelters and information centers have been upgraded in the GB50223-2008 code. The main aspects of the revised GB50011-2001 code include: (a) modification of the seismic intensity specified for the Provinces of Sichuan, Shanxi and Gansu; (b) basic conceptual design for retaining walls and building foundations in mountainous areas; (c) regularity of building configuration; (d) integration of masonry structures and precast Rc floors; (e) requirements for calculating and detailing stair shafts; and (f) limiting the use of single-bay Rc frame structures. Some significant examples of damage in the epicenter areas are provided as a reference in the discussion on the consequences of collapse, the importance of duplicate structural systems, and the integration of Rc and masonry structures.

关键词： Wenchuan earthquake earthquake damage to buildings revision of seismic design codes

Modified extremal optimization for the hard maximum satisfiability problem

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Journal of Zhejiang University-Science c(computers and Electronics) 2011年第7期12卷 589-596页

作者： Guo-qiang ZENG 1,Yong-zai LU 2,Wei-Jie MAO 2 (1 college of Physics & Electronic information engineering,Wenzhou University,Wenzhou 325035,china) (2 State Key Laboratory of Industrial control Technology,institute of cyber-Systems and control,Zhejiang University,Hangzhou 310027,china) college of Physics & Electronic information engineering Wenzhou University Wenzhou China State Key Laboratory of Industrial control Technology Institute of Cyber-Systems and Control Zhejiang University Hangzhou China

Based on our recent study on probability distributions for evolution in extremal optimization (EO),we propose a modified framework called EOSAT to approximate ground states of the hard maximum satisfiability (MAXSAT) problem,a generalized version of the satisfiability (SAT) *** basic idea behind EOSAT is to generalize the evolutionary probability distribution in the Bose-Einstein-EO (BE-EO) algorithm,competing with other popular algorithms such as simulated annealing and *** results on the hard MAXSAT instances from SATLIB show that the modified algorithms are superior to the original BE-EO algorithm.

关键词： Extremal optimization (EO) Evolution Probability distributions Maximum satisfiability (MAXSAT) problem