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On the new results of global attractive set and positive invariant set of the Lorenz chaotic system and the applications to chaos control and synchronization

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Science in China(Series F) 2005年第3期48卷 304-321页

作者： LIAO Xiaoxin 1, 2, 3., FU Yuli 4 & XIE Shengli 4 1. department of control Science & control {3., Huazhong University of Science & technology, Wuhan 43.074, China 2. School of Automation, Wuhan University of Science & technology, Wuhan 43.070, China 3. School of information, Central South University of Economy, Politics and Law, Wuhan 43.064, China 4. School of Electronics & information {3., South China University of technology, Guangzhou 510640, China Correspondence should be addressed to Liao Xiaoxin (email: xiaoxin_liao@***) department of control Science & control {3. Huazhong University of Science & Technology Wuhan China School of Automation Wuhan University of Science & Technology Wuhan China School of information Central South University of Economy Politics and Law Wuhan China School of Electronics & information engineering South China University of Technology Guangzhou China

Constructing a family of generalized Lyapunov functions, a new method is proposed to obtain new global attractive set and positive invariant set of the Lorenz chaotic system. The method we proposed greatly simplifies the complex proofs of the two famous estimations presented by the Russian scholar Leonov. Our uniform formula can derive a series of the new estimations. Employing the idea of intersection in set theory, we extract a new Leonov formula-like estimation from the family of the estimations. With our method and the new estimation, one can confirm that there are no equilibrium, periodic solutions, almost periodic motions, wandering motions or other chaotic attractors outside the global attractive set. The Lorenz butterfly-like singular attractors are located in the global attractive set only. This result is applied to the chaos control and chaos synchronization. Some feedback control laws are obtained to guarantee that all the trajectories of the Lorenz systems track a periodic solution, or globally stabilize an unstable (or locally stable but not globally asymptotically stable) equilibrium. Further, some new global exponential chaos synchronization results are presented. Our new method and the new results are expected to be applied in real secure communication systems.

关键词： Lorenz chaotic system global attractive set positive invariant set globally exponential tracking globally exponential synchronization.

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 {3. 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

Second-order consensus in networks of dynamic agents with communication time-delays

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Journal of Systems engineering and Electronics 2010年第1期21卷 88-94页

作者： Bo Yang1,2, Huajing Fang3. and Hua Wang4 1. School of Navigation, Wuhan University of technology, Wuhan 43.063. P. R. China 2. Wuhan Second Ship Design and Research institute, Wuhan 43.064, P. R. China 3. department of {3. Science and engineering, Huazhong University of Science and technology, Wuhan 43.074, P. R. China 4. department of Aerospace and Mechanical engineering, Boston University, Boston MA02215, USA School of Navigation Wuhan University of Technology Wuhan 430063 P. R. China Wuhan Second Ship Design and Research institute Wuhan 430064 P. R. China department of control Science and engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China department of Aerospace and Mechanical engineering Boston University Boston MA02215 USA

This paper proposes second-order consensus protocols with time-delays and gives the measure of the robustness of the protocols to the time-delay existing in the network of agents with second-order dynamics. By employing a frequency domain method, it is proven that the information states and their time derivatives of all the agents in the network achieve consensus asymptotically, respectively, for appropriate communication timedelay if the topology of weighted network is connected. Particularly, a tight upper bound on the communication time-delay that can be tolerated in the dynamic network is found. The consensus protocols are distributed in the sense that each agent only needs information from its neighboring agents, which reduces the complexity of connections between neighboring agents significantly. Numerical simulation results are provided to demonstrate the effectiveness and the sharpness of the theoretical results for second-order consensus in networks in the presence of communication time-delays.

关键词： second-order consensus protocols dynamic networks algebraic graph theory frequency domain analysis com-munication constraints.

Sufficient and necessary conditions for Lyapunov stability of Lorenz system and their application

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Science China(information Sciences) 2010年第8期53卷 1574-1583页

作者： LUO Qi 1 , LIAO XiaoXin 2 & ZENG ZhiGang 2 1 College of information and control, Nanjing University of information Science and {3., Nanjing 210044, China 2 department of control Science and engineering, Huazhong University of Science and {3., Image Processing and Intelligent control Key Laboratory of Education Ministry of China, Wuhan 43.074, China College of information and control Nanjing University of Information Science and Technology Nanjing China department of control Science and engineering Huazhong University of Science and Technology Image Processing and Intelligent Control Key Laboratory of Education Ministry of China Wuhan China

The sufficient and necessary conditions for Lyapunov stability of the zero equilibrium point of Lorenz system are discussed, and some brief criteria are presented for globally exponential stability, globally asymptotical stability and instability. Furthermore, the behavior of the non-zero equilibrium point of Lorenz system is also investigated, and several sufficient and necessary conditions are provided for locally exponential stability and instability. The established theorems in this paper develop and extend the existing achievements on Lyapunov stability of Lorenz system. In conclusion, by applying the obtained results, some less conservative feedback-control laws are derived to guarantee the globally exponential stability of the chaos control of Chen system, Lu¨ system, Yang-Chen system and Yu-Xia Li system.

关键词： Lorenz system Lyapunov stability sufficient and necessary condition bifurcation values globally exponential synchronization

Molecular dynamics simulations on the structures and properties of ε-CL-20-based PBXs ——Primary theoretical studies on HEDM formulation design

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Science China Chemistry 2007年第6期50卷 737-745页

作者： XU XiaoJuan1,2, XIAO JiJun1, HUANG Hui3. LI JinShan3.& XIAO HeMing1 1 department of Chemistry, Nanjing University of Science and technology, Nanjing 210094, China 2 department of Chemistry, Yancheng Teacher’s College, Yancheng 224002, China 3.{3. of Chemical Materials, China Academy of engineering Physics, mianyang 621900, China department of Chemistry Nanjing University of Science and Technology Nanjing China department of Chemistry Yancheng Teacher’s College Yancheng China institute of Chemical Materials China Academy of Engineering Physics Mianyang China

Five polymer bonded explosives(PBXs)with the base explosive epsilon-CL-20(hexanitrohexaazaisowurtzi-tane),the most important high energy density compound(HEDC),and five polymer binders(Estane 5703.GAP,HTPB,PEG,and F_(23.4))were *** dynamics(MD)method was employed to investigate their binding energies(E_(bind))information and rules were reported for choosing better binders and guiding formulation design of high energy density material(HEDM).According to the calculated binding energies,the ordering of compatibility and stability of the five PBXs was predicted as epsilon-CL-20/PEG 3.≈ epsilon-CL-20/GAP 3.4).By pair correlation function g(r)analyses,hydrogen bonds and vdw are found to be the main interactions between the two *** elasticity and isotropy of PBXs based epsilon-CL-20 can be obviously improved more than pure epsilon-CL-20 *** is not by changing the molecular structures of epsilon-CL-20 for each binder to affect the *** safety and energetic properties of these PBXs are mainly influenced by the thermal capability(C_p^(deg))and density(p)of binders,respectively.

关键词： high energy density material (HEDM), hexanitrohexaazaisowurtzitane (CL-20), polymer bonded explosives (PBXs), molecular dynamics (MD), compatibility, safety properties, mechanical properties, energetic properties

A fast stereoscopic video coding algorithm based on JMVM

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Science China(information Sciences) 2011年第6期54卷 1218-1226页

作者： DENG ZhiPin 1,2 , JIA KeBin 1 , CHAN YuiLam 2 , FU ChangHong 2 & SIU WanChi 2 1 department of Electronic information & control {3., Beijing University of technology, Beijing 100124, China 2 department of Electronic information {3., Hong Kong Polytechnic University, Hong Kong, China department of Electronic information & control {3. Beijing University of Technology Beijing China department of Electronic information engineering Hong Kong Polytechnic University Hong Kong China

In order to exploit the intra-view and inter-view dependencies in stereo video coding, a fast joint motion and disparity estimation algorithm is proposed in this paper. An efficient search strategy based on the motion-disparity constraint is developed, in which both the motion and disparity vectors can be obtained simultaneously with low complexity. Moreover, a credible initial predictive vector set is designed with the aid of the temporal and spatial neighboring blocks so that the coding efficiency can be further enhanced. The experimental results demonstrate that the proposed algorithm can reduce more than 96% coding time compared with the JMVM full search with a negligible quality drop.

关键词： H.264 stereoscopic video coding disparity estimation motion estimation

A new geometric approach to blind source separation of bounded sources

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Progress in Natural Science:Materials International 2009年第7期19卷 891-896页

作者： Jinlong Zhang a, Guoxu Zhoua, Zuyuan Yang a, Xiaoxin Liao b a School of Electrics & information engineering, South China University of technology, Guangzhou 510641, China b {3. of control Science and engineering, Huazhong University of Science and technology, Wuhan 43.074, China School of Electrics & information engineering South China University of Technology Guangzhou 510641 China department of control Science and engineering Huazhong University of Science and Technology Wuhan 430074 China

Based on the minimum-range approach, a new geometric approach is proposed to deal with blind source separation in this paper. The new approach is the batch mode of the original minimum-range approach. Compared with the original approach, the optimization algorithm of the proposed approach needs no parameters and is more efficient and reliable. In addition, the extension of minimum-rangebased approaches is discussed. The simulations show the efficiency of the proposed approach.

关键词： Blind source separation Independent component analysis Minimum-range approach

Estimating the mixing matrix by using less sparsity

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Progress in Natural Science:Materials International 2009年第8期19卷 1027-1031页

作者： Guoxu Zhou a, Zuyuan Yang a, Xiaoxin Liao b, Jinlong Zhanga a School of Electrics & information engineering, South China University of technology, Guangzhou 510641, China b {3. of control Science and engineering, Huazhong University of Science and technology, Wuhan 43.074, China School of Electrics & information engineering South China University of Technology Guangzhou 510641 China department of control Science and engineering Huazhong University of Science and Technology Wuhan 430074 China

In this paper, the nonlinear projection and column masking (NPCM) algorithm is proposed to estimate the mixing matrix for blind source separation. It preserves the samples which are close to the interested direction while suppressing the rest. Compared with the existing approaches, NPCM works efficiently even if the sources are less sparse (i.e., they are not strictly sparse). Finally, we show that NPCM provides considerably accurate estimation of the mixing matrix by simulations.

关键词： Sparse component analysis Blind source separation Particle swarm optimization

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一类控制器摄动系统的H_∞强鲁棒控制

系统工程与电子技术 2004年第4期26卷 507-508,534页

作者：恒庆海北京信息工程学院信息与通信工程系北京100101

为了解决在被控对象和控制器同时摄动时控制系统的设计问题,提出了一般控制系统的强鲁棒性能概念。通过数学模型转换,将控制器的摄动转化为被控对象的摄动。给出了一类可采用H∞混合灵敏度求解强鲁棒控制器的一种设计方法。提高了在被... 详细信息

为了解决在被控对象和控制器同时摄动时控制系统的设计问题,提出了一般控制系统的强鲁棒性能概念。通过数学模型转换,将控制器的摄动转化为被控对象的摄动。给出了一类可采用H∞混合灵敏度求解强鲁棒控制器的一种设计方法。提高了在被控对象和控制器同时摄动时系统的性能。研究了不确定性权函数和性能权函数权函数的选取。考虑到SISO系统的特点,给出了求解强鲁棒PI控制器的简单算法,设计了强鲁棒控制的PI控制器参数。通过仿真示例验证了设计方法的有效性和可行性。

关键词：控制器摄动鲁棒控制强鲁棒性能