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Invariant Sets and Exact Solutions to Higher-Dimensional Wave Equations 被引量:11
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作者 QU Gai-Zhu ZHANG Shun-Li ZHU Chun-Rong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第5期1119-1124,共6页
The invariant sets and exact solutions of the (1 + 2)-dimensional wave equations are discussed. It is shown that there exist a class of solutions to the equations which belong to the invariant set E0 = {u : ux = ... The invariant sets and exact solutions of the (1 + 2)-dimensional wave equations are discussed. It is shown that there exist a class of solutions to the equations which belong to the invariant set E0 = {u : ux = vxF(u),uy = vyF(u) }. This approach is also developed to solve (1 + N)-dimensional wave equations. 展开更多
关键词 wave equation invariant set exact solution
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Finite-time stability with respect to a closed invariant set for a class of discontinuous systems 被引量:3
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作者 程桂芳 慕小武 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第8期1069-1075,共7页
This paper discusses the problem of finite-time stability with respect to a closed, but not necessarily compact, invariant set for a class of nonlinear systems with discontinuous right-hand sides in the sense of the F... This paper discusses the problem of finite-time stability with respect to a closed, but not necessarily compact, invariant set for a class of nonlinear systems with discontinuous right-hand sides in the sense of the Filippov solutions. When the Lyapunov function is Lipschitz continuous and regular, the Lyapunov theorem on finite-time stability with respect to a closed invariant set is presented. 展开更多
关键词 Filippov solution closed invariant set finite-time stability discontinuous system
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Estimating the globally attractive set and positively invariant set of a unified chaotic system 被引量:2
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作者 舒永录 《Journal of Chongqing University》 CAS 2008年第3期216-220,共5页
By constructing two suitable generalized Lyapunov functions,we derived a generalized ellipsoidal estimate of the globally attractive set and positively invariant set of the unified chaotic system with the parameters ... By constructing two suitable generalized Lyapunov functions,we derived a generalized ellipsoidal estimate of the globally attractive set and positively invariant set of the unified chaotic system with the parameters α=1/29 and 1/29<α<2/29,respectively,which extends some related results of Li,et al. [Li DM,Lu JA,Wu XQ,Chen GR,Estimating the global basin of attraction and positively invariant set for the Lorenz system and a unified chaotic system,Journal of Mathematical Analysis and Applications,2006,323(2): 844-853]. The theoretical results obtained in this paper will find wide application in chaos control and synchronization. 展开更多
关键词 generalized Lyapunov function unified chaotic system globally attractive set positively invariant set
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Exact Solutions and Invariant Sets to General Reaction-Diffusion Equation 被引量:1
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作者 JIA Hua-Bing XU Wei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第6期1389-1392,共4页
In this paper, we introduce new invariant sets, and the invariant sets and exact solutions to general reactiondiffusion equation are discussed. It is shown that there exist a class of exact solutions to the equations ... In this paper, we introduce new invariant sets, and the invariant sets and exact solutions to general reactiondiffusion equation are discussed. It is shown that there exist a class of exact solutions to the equations that belong to the invariant sets. 展开更多
关键词 invariant set exact solution general reaction-diffusion equation rotation group scaling group
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Estimating the ultimate bound and positively invariant set for a generalized Lorenz system 被引量:1
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作者 舒永录 张永浩 《Journal of Chongqing University》 CAS 2008年第2期151-154,共4页
A generalized Lyapunov function was employed to investigate the ultimate bound and positively invariant set of a generalized Lorenz system.We derived an ellipsoidal estimate of the ultimate bound and positively invari... A generalized Lyapunov function was employed to investigate the ultimate bound and positively invariant set of a generalized Lorenz system.We derived an ellipsoidal estimate of the ultimate bound and positively invariant set for the generalized Lorenz system,for all the positive values of system parameters a,b,and c.Our results extend the related result of Li,et al.[Li DM,Lu JA,Wu XQ,et al.,Estimating the ultimate bound and positively invariant set for the Lorenz system and a unified chaotic system,Journal of Mathematical Analysis and Application,2006,323(2):844-653]. 展开更多
关键词 generalized Lorenz system ultimate bound positively invariant set generalized Lyapunov function
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The Ellipsoidal Invariant Set of Fractional Order Systems Subject to Actuator Saturation:The Convex Combination Form 被引量:1
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作者 Kai Chen Junguo Lu Chuang Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第3期311-319,共9页
The domain of attraction of a class of fractional order systems subject to saturating actuators is investigated in this paper. We show the domain of attraction is the convex hull of a set of ellipsoids. In this paper,... The domain of attraction of a class of fractional order systems subject to saturating actuators is investigated in this paper. We show the domain of attraction is the convex hull of a set of ellipsoids. In this paper, the Lyapunov direct approach and fractional order inequality are applied to estimating the domain of attraction for fractional order systems subject to actuator saturation. We demonstrate that the convex hull of ellipsoids can be made invariant for saturating actuators if each ellipsoid with a bounded control of the saturating actuators is invariant. The estimation on the contractively invariant ellipsoid and construction of the continuous feedback law are derived in terms of linear matrix inequalities (LMIs). Two numerical examples illustrate the effectiveness of the developed method. © 2014 Chinese Association of Automation. 展开更多
关键词 ALGEBRA Computational geometry Linear matrix inequalities Numerical methods Saturation (materials composition)
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Stabilizing model predictive control scheme for piecewise affine systems with maximal positively invariant terminal set
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作者 Fu Chen Guangzhou Zhao Xiaoming Yu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期1090-1094,共5页
An efficient algorithm is proposed for computing the solution to the constrained finite time optimal control (CFTOC) problem for discrete-time piecewise affine (PWA) systems with a quadratic performance index. The... An efficient algorithm is proposed for computing the solution to the constrained finite time optimal control (CFTOC) problem for discrete-time piecewise affine (PWA) systems with a quadratic performance index. The maximal positively invariant terminal set, which is feasible and invariant with respect to a feedback control law, is computed as terminal target set and an associated Lyapunov function is chosen as terminal cost. The combination of these two components guarantees constraint satisfaction and closed-loop stability for all time. The proposed algorithm combines a dynamic programming strategy with a multi-parametric quadratic programming solver and basic polyhedral manipulation. A numerical example shows that a larger stabilizable set of states can be obtained by the proposed algorithm than precious work. 展开更多
关键词 constrained optimal predictive control multi-parametric quadratic programming dynamic programming receding horizon control positively invariant set.
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La Shalle's invariant-set-theory based asymptotic synchronization of duffing system with unknown parameters
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作者 禹东川 吴爱国 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第1期95-99,共5页
A novel La Shalle's invariant set theory (LSIST) based adaptive asymptotic synchronization (LSISAAS) method is proposed to asymptotically synchronize Duffing system with unknown parameters which also are consider... A novel La Shalle's invariant set theory (LSIST) based adaptive asymptotic synchronization (LSISAAS) method is proposed to asymptotically synchronize Duffing system with unknown parameters which also are considered as system states. The LSISASS strategy depends on the only information, i.e. one state of the master system. According to the LSIST, the LSISASS method can asymptotically synchronize fully the states of the master system and the unknown system parameters as well. Simulation results also validate that the LSISAAS approach can obtain asymptotic synchronization. 展开更多
关键词 chaotic synchronization adaptive state observer La Shalle's invariant set theory
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Invariant Sets and Exact Solutions to Nonlinear Diffusion Equations with x-Dependent Convection and Absorption
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作者 JIA Hua-Bing XU Wei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期821-826,共6页
In this paper, we introduce a new invariant set Eo={u:ux=f'(x)F(u)+ε[g'(x)-f'(x)g(x)]F(u)×exp(-∫^u1/F(z)dz)}where f and g are some smooth functions of x, ε is a constant, and F is a smooth... In this paper, we introduce a new invariant set Eo={u:ux=f'(x)F(u)+ε[g'(x)-f'(x)g(x)]F(u)×exp(-∫^u1/F(z)dz)}where f and g are some smooth functions of x, ε is a constant, and F is a smooth function to be determined. The invariant sets and exact sohltions to nonlinear diffusion equation ut = ( D(u)ux)x + Q(x, u)ux + P(x, u), are discussed. It is shown that there exist several classes of solutions to the equation that belong to the invariant set Eo. 展开更多
关键词 invariant set exact solution nonlinear diffusion equations rotation group scaling group
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A Note on Invariant Sets
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作者 瞿成勤 苏维宜 许勇 《Northeastern Mathematical Journal》 CSCD 2000年第4期451-453,共3页
The lower bound of Hausdorff dimension of the invariant set is given.
关键词 invariant set Hausdorff dimension iterated function
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Lacunary Invariant Statistical Convergence Of Sequences Of Sets With Respect To A Modulus Function
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作者 Nimet Pancaroglu Fatih Nuray 《Journal of Mathematics and System Science》 2015年第3期122-126,共5页
In this paper, we introduce and study the concept of lacunary invariant convergence for sequences of sets with respect to modulus functionfand give some inclusion relations.
关键词 Statistical convergence lacunary invariant convergence sequences of sets modulus function
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Completely Invariant Domains of Holomorphic Self-Maps on C
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作者 方丽萍 《Journal of Beijing Institute of Technology》 EI CAS 1997年第3期187-191,共5页
Let/(z) be a holomorph.self-map on C.-G-(0) with essential singularities 0 and It is proved that f(z) has a completdy invariant domain.D.F(f),then D is doubly connected and D contains all the singularities of the inv... Let/(z) be a holomorph.self-map on C.-G-(0) with essential singularities 0 and It is proved that f(z) has a completdy invariant domain.D.F(f),then D is doubly connected and D contains all the singularities of the inverse of f(z),moreover,if f is of the finite type, then D=F(f). This result implies that f(z) has at most one completely invariant domain in F(f). 展开更多
关键词 holomorphic maps completely invariant domains Fatou set
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THE INVARIANT DISTRIBUTION OF NON-FULLY DEVELOPED CHAOS FOR THE TENT MAP
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作者 YU Jiang HU Gang 《Chinese Physics Letters》 SCIE CAS 1986年第8期357-360,共4页
The invariant distribution of non-fully developed chaos has been investigated for the tent map.A very sophisticated sequence set which corresponds to exact solutions of the invariant distribution has been found,as a s... The invariant distribution of non-fully developed chaos has been investigated for the tent map.A very sophisticated sequence set which corresponds to exact solutions of the invariant distribution has been found,as a special case,the MSS(Metropolis-Stein-Stein)sequence is also included in this sequence set. 展开更多
关键词 invariant set. map.
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一类具有饱和恢复率的随机SIR传染病模型的持久性
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作者 刘娟 吴延敏 《廊坊师范学院学报(自然科学版)》 2024年第3期5-8,13,共5页
在确定型模型的基础上,考虑随机因素,得到了一类具有饱和发生率的随机SIR模型。首先给出随机模型的正不变集,进而介绍持久性含义,利用Ito公式及强大数定律得到了疾病流行的充分性条件。结果表明,当白噪声强度满足一定的参数条件时,染病... 在确定型模型的基础上,考虑随机因素,得到了一类具有饱和发生率的随机SIR模型。首先给出随机模型的正不变集,进而介绍持久性含义,利用Ito公式及强大数定律得到了疾病流行的充分性条件。结果表明,当白噪声强度满足一定的参数条件时,染病类群体不会消失,这对于控制疾病的蔓延是不利的。 展开更多
关键词 随机SIR模型 饱和恢复率 正不变集 ITO公式
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Hybrid Dynamic Variables-Dependent Event-Triggered Fuzzy Model Predictive Control 被引量:1
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作者 Xiongbo Wan Chaoling Zhang +2 位作者 Fan Wei Chuan-Ke Zhang Min Wu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期723-733,共11页
This article focuses on dynamic event-triggered mechanism(DETM)-based model predictive control(MPC) for T-S fuzzy systems.A hybrid dynamic variables-dependent DETM is carefully devised,which includes a multiplicative ... This article focuses on dynamic event-triggered mechanism(DETM)-based model predictive control(MPC) for T-S fuzzy systems.A hybrid dynamic variables-dependent DETM is carefully devised,which includes a multiplicative dynamic variable and an additive dynamic variable.The addressed DETM-based fuzzy MPC issue is described as a “min-max” optimization problem(OP).To facilitate the co-design of the MPC controller and the weighting matrix of the DETM,an auxiliary OP is proposed based on a new Lyapunov function and a new robust positive invariant(RPI) set that contain the membership functions and the hybrid dynamic variables.A dynamic event-triggered fuzzy MPC algorithm is developed accordingly,whose recursive feasibility is analysed by employing the RPI set.With the designed controller,the involved fuzzy system is ensured to be asymptotically stable.Two examples show that the new DETM and DETM-based MPC algorithm have the advantages of reducing resource consumption while yielding the anticipated performance. 展开更多
关键词 Dynamic event-triggered mechanism(DETM) hybrid dynamic variables model predictive control(MPC) robust positive invariant(RPI)set T-S fuzzy systems
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Heteroclinic Cycles in a Class of 3-Dimensional Piecewise Affine Systems
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作者 Minghao Liu Ruimin Liu 《Journal of Applied Mathematics and Physics》 2024年第2期488-508,共21页
This paper explores the existence of heteroclinic cycles and corresponding chaotic dynamics in a class of 3-dimensional two-zone piecewise affine systems. Moreover, the heteroclinic cycles connect two saddle foci and ... This paper explores the existence of heteroclinic cycles and corresponding chaotic dynamics in a class of 3-dimensional two-zone piecewise affine systems. Moreover, the heteroclinic cycles connect two saddle foci and intersect the switching manifold at two points and the switching manifold is composed of two perpendicular planes. 展开更多
关键词 Piecewise Affine System Heteroclinic Cycle Chaotic invariant set
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一类微分系统变号解的存在性和多解性
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作者 张慧星 高妍 姚香娟 《郑州大学学报(理学版)》 CAS 北大核心 2024年第1期88-94,共7页
下降流不变集方法是研究椭圆问题变号解存在性的一种很有效的理论工具。运用下降流不变集方法和抽象临界点理论,研究一类基尔霍夫-薛定谔-泊松系统,证明得到基尔霍夫-薛定谔-泊松系统变号解的存在性以及多解性。
关键词 基尔霍夫-薛定谔-泊松系统 变号解 下降流不变集 临界点理论
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基于Rough Set的目标快速识别方法
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作者 黄雷 郭雷 马迎军 《微计算机信息》 2009年第31期8-9,17,共3页
主要研究了基于粗糙集和支持向量机的模式分类技术,结合遥感图像中军用飞机目标识别进行了理论分析和实验研究。设计了基于粗糙集和决策有向无环图的支持向量机模式识别分类器,对分类的性能进行了分析研究,利用粗糙集理论中属性约简方... 主要研究了基于粗糙集和支持向量机的模式分类技术,结合遥感图像中军用飞机目标识别进行了理论分析和实验研究。设计了基于粗糙集和决策有向无环图的支持向量机模式识别分类器,对分类的性能进行了分析研究,利用粗糙集理论中属性约简方法去除冗余属性,降低飞机特征维数,提出使用决策有向无环图支持向量机进行训练并对待识别目标预测。实验表明,本文提出的方法可提高识别速度及预测分类精度。 展开更多
关键词 目标识别 不变矩 复数矩 粗糙集 支持向量机 遥感图像
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A Dual-mode Nonlinear Model Predictive Control with the Enlarged Terminal Constraint Sets 被引量:16
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作者 ZOU Tao LI Shao-Yuao DING Bao-Cang 《自动化学报》 EI CSCD 北大核心 2006年第1期21-27,共7页
Aiming at a class of nonlinear systems with multiple equilibrium points, we present a dual-mode model predictive control algorithm with extended terminal constraint set combined with control invariant set and gain sch... Aiming at a class of nonlinear systems with multiple equilibrium points, we present a dual-mode model predictive control algorithm with extended terminal constraint set combined with control invariant set and gain schedule. Local LQR control laws and the corresponding maximum control invariant sets can be designed for finite equilibrium points. It is guaranteed that control invariant sets are overlapped each other. The union of the control invariant sets is treated as the terminal constraint set of predictive control. The feasibility and stability of the novel dual-mode model predictive control are investigated with both variable and fixed horizon. Because of the introduction of extended terminal constrained set, the feasibility of optimization can be guaranteed with short prediction horizon. In this way, the size of the optimization problem is reduced so it is computationally efficient. Finally, a simulation example illustrating the algorithm is presented. 展开更多
关键词 不变量集 非线性模型 预先控制 非线性约束系统 增益表
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Better Hausdorff Dimension Estimations of Quadratic and Cubic Functions' Julia Sets
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作者 方丽萍 张春红 《Journal of Beijing Institute of Technology》 EI CAS 2006年第1期123-126,共4页
More accurate Hausdorff dimension estimations of Julia sets for two simple functions are given by the methods of composition mapping and invariant set of contraction mapping. For quadratic function fc ( z ) = z^2 ... More accurate Hausdorff dimension estimations of Julia sets for two simple functions are given by the methods of composition mapping and invariant set of contraction mapping. For quadratic function fc ( z ) = z^2 + c(c ∈^C), the range of parameter c is expanded largely and a result on the Hausdorff dimension of its Julia set is gained. Similarly, a better result is obtained for cubic function fc(z) = z^3 + c(c ∈ ^C). 展开更多
关键词 COMPOSITION contraction mapping invariant set Hausdorff dimension
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