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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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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
不变的集合和准确答案(1+ 2 ) 维的波浪方程被讨论。在那里存在,这被显示出属于不变的集合 E <SUB>0</SUB>= 的方程的答案的一个类 { u:u <SUB > x </SUB>= v <SUB > x </SUB > F (u) , u <S... 不变的集合和准确答案(1+ 2 ) 维的波浪方程被讨论。在那里存在,这被显示出属于不变的集合 E <SUB>0</SUB>= 的方程的答案的一个类 { u:u <SUB > x </SUB>= v <SUB > x </SUB > F (u) , u <SUB > y </SUB>= v <SUB > y </SUB > F (u)} 。这条途径也被开发解决(1 + N ) 维的波浪方程。 展开更多
关键词 波动方程 不变集 精确解 解题方法
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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 广义函数 统一混沌系统 积极不变集 研究分析
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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
在这篇论文,我们介绍新不变的集合,并且到一般反应散开方程的不变的集合和准确答案被讨论。在那里存在,这被显示出属于不变的集合的方程的准确答案的一个班。
关键词 不变集 精确解法 普通反作用-扩散方程 旋度群 标定群
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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 不变集 数学分析 计算方法 洛伦兹系统
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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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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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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
<正> In this paper,we introduce a new invariant set _0={u:u_x=f'(x)F(u)+ε[g'(x)-f'(x)g(x)]F(u)×exp(-i∫~u 1/F(z) dz)},where f and g are some smooth functions of x,ε is a constant,and F is a sm... <正> In this paper,we introduce a new invariant set _0={u:u_x=f'(x)F(u)+ε[g'(x)-f'(x)g(x)]F(u)×exp(-i∫~u 1/F(z) dz)},where f and g are some smooth functions of x,ε is a constant,and F is a smooth function to bedetermined.The invariant sets and exact solutions to nonlinear diffusion equation u_t=(D(u)u_x)_x+Q(x,u)u_x+P(x,u),are discussed.It is shown that there exist several classes of solutions to the equation that belong to the invariant set _0. 展开更多
关键词 不变量组 求解方法 非线性扩散方程式 数学
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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
关键词 收敛序列 缺位 模函数 设置 统计
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Hybrid Dynamic Variables-Dependent Event-Triggered Fuzzy Model Predictive Control
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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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THE EXISTENCE OF OVERLARGE SETS OF IDEMPOTENT QUASIGROUPS
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作者 常彦勋 雷建国 《Acta Mathematica Scientia》 SCIE CSCD 2004年第2期165-170,共6页
A idempotent quasigroup (Q, o) of order n is equivalent to an n(n-1)×3 partial orthogonal array in which all of rows consist of 3 distinct elements. Let X be a (n+1)-set. Denote by T(n+1) the set of (n+1)n(n-1) o... A idempotent quasigroup (Q, o) of order n is equivalent to an n(n-1)×3 partial orthogonal array in which all of rows consist of 3 distinct elements. Let X be a (n+1)-set. Denote by T(n+1) the set of (n+1)n(n-1) ordered triples of X with the property that the 3 coordinates of each ordered triple are distinct. An overlarge set of idempotent quasigroups of order n is a partition of T(n+1) into n+1 n(n-1)×3 partial orthogonal arrays A_x, x∈X based on X\{x}. This article gives an almost complete solution of overlarge sets of idempotent quasigroups. 展开更多
关键词 Pairwise balanced design conjugate invariant subgroup overlarge set of idempotent quasigroups
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THE INVARIANT DISTRIBUTION OF NON-FULLY DEVELOPED CHAOS FOR THE TENT MAP
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作者 余江 胡岗 《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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“预构”及衍生——韦伯恩《三首歌》(Op.25)的十二音序列技法分析 被引量:1
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作者 田园 《音乐探索》 2023年第1期60-74,共15页
简洁、极具推理性以及最大限度地组织化代表了韦伯恩音乐创作的一些重要特征,通过“预构”((1))某些材料使其不断衍生,则成为实现这种具有高度理性的、组织化音乐的重要手段,此种做法在其晚期的一些作品中体现得尤为明显。论文以韦伯恩... 简洁、极具推理性以及最大限度地组织化代表了韦伯恩音乐创作的一些重要特征,通过“预构”((1))某些材料使其不断衍生,则成为实现这种具有高度理性的、组织化音乐的重要手段,此种做法在其晚期的一些作品中体现得尤为明显。论文以韦伯恩在其十二音序列技法的成熟期创作的声乐套曲《三首歌》(Op.25)为研究对象,通过分析其如何通过所“预构”的材料衍生出整套作品,以获得音乐的凝聚力与音响同质性,并以此为研究视角,进一步探讨韦伯恩的十二音序列技法特征。 展开更多
关键词 韦伯恩 “预构” 集合3-3 对称 不变性
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一类非线性Schrodinger方程变号解的存在性
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作者 陈瑾 范馨香 《兰州文理学院学报(自然科学版)》 2023年第4期18-22,51,共6页
研究了一类非线性Schr dinger方程:-Δu+V x u=f x,u,x∈RN,其中f的原函数满足的超二次条件比(AR)条件更弱.利用下降流不变集方法,证明了该方程存在变号解.
关键词 SCHRODINGER方程 下降流不变集 变号解
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