一类四阶非线性系统的全局渐近稳定性

运用Liapunov第二方法讨论了一类四阶非线性系统的全局渐近稳定性,通过构造出较好的Liapunov函数,获得到了其零解全局渐近稳定的充分性准则,去掉了一般要求Liapunov函数具有无穷大这个较强的条件,并推广了部分文献所研究的非线性系统.     

一类微分方程系统正平衡解的存在性与全局稳定性

本文研究了一个自治的非线性微分方程系统,得到了系统正平衡点存在唯一的充分条件,通过伸缩变换法讨论了正平衡点局部稳定性,并运用构造Liapunov函数方法得到了它的全局渐近稳定性.     

一类随机脉冲微分系统的稳定性

本文给出了随机脉冲微分系统零解的最终稳定性的定义,利用Liapunov函数,得到了非线性随机脉冲微分系统零解一致最终稳定性及一致最终渐进稳定性和最终不稳定的充分条件.     

两自由度非线性振动系统周期运动及其稳定性研究

运用Liapunov函数方法,对一类两自由度非线性振动系统周期运动及其稳定性进行了研究,得到了存在唯一渐近稳定的周期解的充分条件.     

异常情况时的Liapunov-Kozlov法

Kozlov将Liapunov第一方法推广到非线性力学系统,用来研究保守力和耗散力场中,运动力学系统平衡位置的不稳定性.在平衡位置分析惯性张量的异常,或者Rayleigh耗散函数系数矩阵的异常.在稳定性分析中,实际上不可能应用Liapunov逼近法,因为平衡位置的存在条件,和运动微分方程解的唯一性条件,均无法得到满足.Kozlov的广义Liapunov第一方法,不仅适用上面提及的条件,此外,还知道同样的代数表达式得到满足.给出了3个关于平衡位置的不稳定性定理.用一个例子,举例说明了得到的结果.     

旋涡运动的稳定性与角动量守恒

本文利用角动量作为Liapunov函数建立二维的圆形涡块及涡环在有限或无限区域上的(Liapunov)非线性稳定性.     

一类非线性系统周期解的存在唯一性及其渐近性态

利用Liapunov函数方法,研究了一类一般的非线性系统周期解的存在唯一性与渐近稳定性,得到了存在唯一渐近稳定周期解的充分条件。     

四阶非线性周期系统周期解的存在唯一性

本文利用Liapunov函数方法,研究了一类具有缓变系数的四阶非线性非自治周期系统的周期解的存在唯一性及其渐近稳定性.我们得到了保证这些系统存在唯一稳定周期解的充分条件,并对系数的缓变范围作了较为精确的估计.     

一类非线性系统周期解的存在唯一性

运用Liapunov函数方法,研究了一类四阶非线性系统,得到了该非线性系统存在唯一渐近稳定的周期解的充分条件.     

NFDE的Lurie型系统的绝对稳定性

1.引言 文[2]研究了一般的RFDE的Lurie型系统的绝对稳定性,推广了[5]、[7]的结果。E.N.Chukwu用Liapunov泛函研究了某一类NFDE的Lurie系统的绝对稳定性,其控制执行机构为一维情形。本文就m个非线性执行机构的情形,用POPOV频率特性方法讨论NFDE的Lurie型系统的绝对稳定性,并推广了[2]的某些结果。 我们考虑下列直接控制系统     

非线性非定常系统在经常作用干扰下的稳定性定理——李雅普诺夫间接法

研究在经常作用干扰下的稳定性是研究李雅普诺夫意义下稳定性的深入和发展,并且更有实际意义,因为干扰往往并不是一次的.关于经常作用干扰下的稳定性,马尔金提出了一个一般定理;但实用它必须找出满足一定条件的李雅普诺夫函数.这对于非线性非定常系统是很困难的.本文根据李雅普诺夫间接法的原理,将之推广应用到判别非线性非定常系统在经常作用干扰下的稳定性,证明了一个重要结论.     

Some remarks about stability of nonlinear discrete-time control systems

We study stability and stabilizability properties of nonlinear discrete-time control systems by means of Liapunov functions. We give a characterization of the uniform bounded-input-bounded-state stability property of nonlinear systems in the framework of second Liapunov method. We find an explicit feedback law stabilizing a discrete-time control system affine-in-control under the Jurdjevic-Quinn approach. Received April 2000     

Existence of a global liapunov functional for certain classes of nonlinear distributed systems : PMM vol. 40, n 6, 1976, pp. 1135–1142

The existence of a global Liapunov functional for nonlinear evolutionary equations in a Hilbert space is investigated as a continuation of paper [1], The results obtained represent a generalization of the results of the theory of absolute stability [2, 3], for the systems with infinite dimensional phase space, and are used for investigation of the nonlocal stability and instability of nonlinear distributed systems. The conditions of existence of the global Liapunov functional obtained are illustrated by an example of a nonlinear parabolic system defined in the interval [0, 1], The concept of a Liapunov functional was first introduced and used with success in [4].     

非线性有限时滞脉冲泛函微分系统的稳定性

研究了一类非线性有限时滞脉冲泛函微分系统,利用比较原理和Lyapunov函数,得到了系统零解一致最终稳定性及一致最终渐近稳定性的充分条件.     

Stability in first approximation of stochastic systems with after effect : PMM vol. 40, n 6, 1976, pp. 1116–1121

The theorem on existence of the Liapunov functionals and the theorem on stability in first approximation for a stochastic differential equation with aftereffect are proved.The suggestion of the replacement of Liapunov functions by functionals [1] in the investigation of the stability of ordinary differential equations with lag, has been widely utilized in dealing with determinate systems, as well as in the case of linear and nonlinear stochastic systems (see e. g. [2 – 11]). Results concerning the stability in the first approximation were obtained for stochastic systems in [12 – 18] and others. Use of Liapunov functionals for the differential equations with aftereffect was first encountered in [1, 19, 20] where the inversion theorems were proved and conditions for the stability in first approximation were obtained.Below a stochastic differential equation with aftereffect is investigated where the random perturbations represent an arbitrary process with independent increments.     

Two families of liapunov functions for functional differential systems

Two families of Liapunov functions are employed to study the global stability and boundedness of functional differential systems. New stability and boundedness theorems are obtained. Applications of these theorems to some nonlinear differential systems with infinite delay are discussed. Project supported by the National Science Foundation of China Under Grants 69871005     

Weight Functions Method in Stability Study of Systems

A new method for systems stability analysis is presented. This method is called weight functions method and it replaces the problem of Liapunov function finding with a problem of finding a number of functions (weight functions) equal to the number of first order differential equations describing the system. It is known that there are not general methods for finding Liapunov functions. The weight functions method is simpler than the classical method since one function at a time has to found. Conditions of solution stability for linear and nonlinear systems and some examples are presented. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)     

用Ляпунов-Popov 方法估计电力系统的暂态稳定域

在电力系统暂态稳定问题的研究中,应用直接法与惯用的逐步计算法相比较,有其优越之处:能够提供稳定度指标,能够快速提供临界的重合闸时间的估计.而不必计算各种假定重合闸时间下的摇摆曲线,比较适合于在线的动态安全监控.因此,十几年来,稳定性理论在电力系统中的应用已引起国内外学者的注意,现已有不少研究工作.七十年代以来,现代非线性控制理论的发展,提供了一类构造函数的方法.这一方法首先由 Pai 及 Willems 应用于电力系统的稳定分析中.