统一混沌系统的全局指数吸引集的新结果

研究了参数α∈[1/29,14/173)时,统一混沌系统的全局指数吸引集问题.通过线性变换和广义Lyapunov函数方法,给出了系统最终上界的精确估计.所得结果发展和丰富了现有混沌系统吸引集的结果,并将在混沌控制和同步中得到广泛应用.     

时滞Hopfield神经网络模型的全局吸引性和全局指数稳定性

对具有时滞的Hopfield神经网络模型,在非线性神经元激励函数是Lipschitz连续(而非已有的大部分文献中假设是Sigmoid函数)的条件下,通过构造适当的泛函,给出了这类模型全局吸引和平衡点全局指数稳定的易于验证的充分条件。     

非自治变时滞Cohen-Grossberg网络的Lagrange稳定性和全局指数吸引集

基于考虑两种不同类型的激活函数,本文研究了非自治变时滞Cohen-Grossberg神经网络（CGNN）在Lagrange意义下的全局指数稳定性,通过利用新的不等式技巧和构造恰当的Lyapunov泛函给出非自治变时滞CGNN模型在Lagrange意义下全局指数稳定性（即一致有界性）以及对其全局指数吸引集估计的代数判据,并给出应用例子加以验证.     

广义时滞Logistic方程的全局吸引性

研究了如下广义时滞Logistic方程dN(t)/dt=r(t)N(t)[1-N(t(t))/K]^α,t≥0,得到其正平衡点全局吸引的一个充分条件,即∫0^∞r(t)dt=∞,且对充分大的t,∫g(t)^tr(s)ds≤h(α）,这改进了由Chen M.P.和Yu,J.S.等建立的结果。     

切换系统的全局指数稳定性

提出了一种确定切换系统稳定性分析的方法.引入了两个相关的实例(非完整系统和约束摆)进行说明.用有限个模型的集合组成非线性模型,且切换序列可以是任意的.假定在切换瞬间状态不出现跳跃,并且不出现Zeno现象,即在每个有界时间段上,切换次数是有限的.在对所确定切换系统的分析中,应用了多次Liapunov函数,并证明了全局指数稳定性.系统的指数稳定性平衡关系到实际应用,因为这样的系统有着更强健的抗干扰能力.     

对称有向图的广义本原指数集

一个有向图Ｄ称为本原有向图,若存在某自然数ｋ,使Ｄ中任一点ｕ到任一点ｖ都有长为ｋ之途径。若Ｄ是一个对称有向图,则Ｄ是本原的当且仅当Ｄ对应的无向图Ｇ连通且至少包含一个奇圈。本文研究最小奇圈长为ｒ的ｎ阶对称本原有向图,完全刻划了第一类广义本原指数集,并部分地解决了第三类广义本原指数集的刻划问题。     

变时滞Hopfield神经网络的全局吸引性和全局指数稳定性

对一类具时滞的Hopfeild型神经网络模型,在非线性神经元激励函数只要求满足Lipschitz连续的条件下,利用推广的Halanay时延微分析不等式、Dini导数以及泛函微分析技术,给出了这类模型的平衡点全局指数稳定性和全局吸引性的充分条件,这些条件易于检验,且改进和推广了前人的结论.此外,此文给出了研究神经网络模型的全局吸引性的微分不等式比较方法.     

分离变量非线性系统的全局稳定性

借助Lyapunov函数方法 ,讨论了一类分离变量系统的全局稳定性和全局指数稳定性 ,得到了由系统自身特点所给出的几个显示代数判据 ,这些充分性结论为实际应用提供方便 ,推广了有关文献中的一些结果 .     

含脉冲的Hopfield神经网络的全局指数稳定性

研究了一类含脉冲的Hopfield神经网络的全局指数稳定性.利用同胚映射理论、Lyapunov函数思想和不等式技巧,给出了平衡点的存在唯一性和全局指数稳定性的新的判别准则.     

一类微分方程零解全局弱吸引和全局吸引到充要条件

考虑二阶微分方程 x =φ(y)-F(x),y=- g(x)q(y) 零解的全局弱吸引和全局吸引性, 说明了Filippov条件(A₂) 不能排除最大椭圆扇形S^* 的存在性, 也不能排除∂S^* 作为其外侧邻域轨线正向极限集的可能. 全面回答了文献[8]末提出的问题;得到了方程(E)满足或不满足Filippov 条件时零解全局弱吸引和全局吸引的一系列充分必要条件, 同时也得到了零解全局渐近稳定的一些新条件.     

New estimate the bounds for the generalized Lorenz system

The bound of a chaotic system is important for chaos control, chaos synchronization, and other applications. In the present paper, the bounds of the generalized Lorenz system are studied, based on the Lyapunov function theory and the Lagrange multiplier method. We obtain a precise bound for the generalized Lorenz system. The rate of the trajectories is also obtained. Furthermore, we perform the numerical simulations. Numerical simulations are presented to show the effectiveness of the proposed scheme. Copyright © 2014 John Wiley & Sons, Ltd.     

广义凸函数相关集合的稠密性问题

应用新方法,研究十二类广义凸函数相关集合的稠密性问题.证明了其中的八个集合在[0,1]中是稠密的.应用反例说明了其中的四个集合在[0,1]中不必稠密.     

广义递归集

对应于定义在一个由有限字符集Ｓ＝｛ａｉ｜１≤ｉ≤ｔ｝　所生成的自由半群Ｓ＊上的自同态映射θ，我们考虑Ｒｄ上的映射族（θ）＝｛Ｌ（ａｉ，ａｊ，ｋ，θ）｜１≤ｋ≤ｗ（ｉ，ｊ）｝　及同态映射ｆ：Ｓ　　满足在此框架上构造出广义递归集　　．此外当　为同态映射族时给出了其Ｈａｕｓｄｏｒｆｆ维数的上界估计；当　　为共形压缩映射族时确定了其Ｈａｕｓｄｏｒｆｆ维数.     

Generalized Quasi—Variational Inequalities on Paracompact Sets

Ｔｈｉｓｐａｐｅｒｉｓｃｏｎｔｉｎｕａｔｉｏｎｓｏｆ［１］，ｗｅｓｔｉｌｌｔｏｕｓｅｍａｒｋｓａｎｄｔｅｒｍｓｉｎ［１］ａｎｄｔｈｅｏｔｈｅｒｔｅｒｍｓａｇｒｅｅｗｉｔｈ［２］ａｎｄ［３］．ＬｅｔＥａｎｄＦｂｅｔｗｏＨａｕｓｄｏｒｆｆｔｏｐｏｌｏｇｉｃａｌｖｅｃｔｏｒｓｐａｃｅｓ，ＸＥ，ＹＦｂｅｔｗｏｎｏｎｅｍｐｔｙｓｅｔｓ，ＦｂｅｔｈｅｄｕａｌｓｐａｃｅｏｆＦ，Ａ：Ｘ→２ＹａｎｄＢ：Ｙ→２Ｆｂｅｔｗｏｓｅｔ－ｖａｌｕｅｄｍａｐｐｉｎｇ，Ｔ：Ｙ→Ｘｂｅｉｎｖｅｒｔｉｂｌｅ．Ｉｎｔｈｉｓｐ…     

Ultimate bound sets of a hyperchaotic system and its application in chaos synchronization

In this article, we investigate globally exponentially attractive sets and chaos synchronization for a hyperchaotic system, namely, Lorenz–Stenflo system. For this system, two ellipsoidal globally exponentially attractive sets are derived based on generalized Lyapunov function theory and the extremum principle of function. Furthermore, we propose linear feedback control with a one, two, three, and four inputs to realize globally exponential synchronization of two four‐dimesional hyperchaotic systems using inequality techniques. Numerical simulations are presented to show the effectiveness of the proposed synchronization scheme. © 2014 Wiley Periodicals, Inc. Complexity 20: 30–44, 2015     

广义直觉模糊集的范畴

In this paper, category GIFS of generalized intuitionistic fuzzy sets(GIF) is built up. Topoi properties of category GIFS axe studied. Firstly， it is proved that the category GIFS has all topoi properties except that it has no subobject classifiers， Secondly， it is proved that the category GIFS has middle object and consequently GIFS is a weak topos.Thirdly， by the use of theory of weak topos GIFS，the power object of an object in GIFS is studied.     

Dynamical behaviors of a new hyperchaotic system

Currently, chaotic systems and chaos‐based applications are commonly used in the engineering fields. One of the main structures used in these applications is chaotic control and synchronization. In this paper, the dynamical behaviors of a new hyperchaotic system are considered. Based on Lyapunov Theorem with differential and integral inequalities, the global exponential attractive sets and positively invariant sets are obtained. Furthermore, the rate of the trajectories is also obtained. The global exponential attractive sets of the system obtained in this paper also offer theoretical support to study chaotic control, chaotic synchronization for this system. Computer simulation results show that the proposed method is effective. Copyright © 2014 John Wiley & Sons, Ltd.     

关于广义函数赋值问题的完善与积分问题

本文采用非标准分析方法，首先对广义函数的赋值问题进行了完善；接着界定了广义函数的积分；最后讨论了广义函数的广义连续性．     

Downward Sets and their separation and approximation properties

We develop a theory of downward subsets of the space ^I, where I is a finite index set. Downward sets arise as the set of all solutions of a system of inequalities x^I,f_t(x)0 (tT), where T is an arbitrary index set and each f _t (tT) is an increasing function defined on ^I. These sets play an important role in some parts of mathematical economics and game theory. We examine some functions related to a downward set (the distance to this set and the plus-Minkowski gauge of this set, which we introduce here) and study lattices of closed downward sets and of corresponding distance functions. We discuss two kinds of duality for downward sets, based on multiplicative and additive min-type functions, respectively, and corresponding separation properties, and we give some characterizations of best approximations by downward sets. Some links between the multiplicative and additive cases are established.