具线性脉冲的微分系统吸收区域的估计

本文讨论具线性脉冲影响的微分系统的吸收区域问题 ,得到吸收区域估计的一个解析表达式 ,并给出了在生态学上应用的例子 .     

Banach空间中基于Neumann引理的拟线性广义逆扰动定理

本文给出Banach空间中闭线性算子的Moore-Penrose有界拟线性投影广义逆的一种新的扰动分析方法.运用的核心工具是广义Neumann引理,这与以往其他结果中所运用的广义Banach引理的处理方法极为不同,得到了闭线性算子的MoorePenrose有界拟线性广义逆的又一个扰动定理及三个误差界不等式.     

Banach空间中闭线性算子广义预解式存在定理

在Banach空间中研究闭线性算子广义逆扰动问题和广义预解式存在性问题.给出了闭线性算子广义逆在T-有界扰动下的一些稳定特征,这些特征推广了在有界线性算子情形、闭线性算子有界扰动情形以及闭线性算子保值域或保核空间情形的一些已知结果.以此为基础,得到了闭线性算子广义预解式存在的一些充要条件及其广义预解式的显式表达式.作为应用,给出了闭Fredholm算子和闭半-Fredholm算子的广义预解式存在性特征.     

线性微分系统的广义反射函数

研究了线性微分系统的广义反射函数,作为应用,给出了线性微分系统具有三角型反射矩阵的充要条件.     

分数阶线性退化微分系统有限时间镇定性问题

本文通过构造新的Lyapunov函数,利用线性矩阵不等式(LMI)和广义Gronwall不等式,研究了分数阶线性退化微分系统的有限时间镇定性问题.充分考虑退化和扰动对系统稳定性的影响,给出了在状态反馈控制器作用下,分数阶退化微分系统在有限时间内镇定的充分条件.并通过两个例子验证了定理条件的可行性.     

随机变时滞不确定性系统的鲁棒稳定性

本文讨论了一类随机变时滞不确定性线性微分系统的鲁棒稳定性。参数的不确定性表现为参数是随时间变化的未知函数,但是时范数有界的。利用线性矩阵不等式和Lyapunov函数的方法给出一些相关的稳定性结论。     

闭算子的线性斜投影广义逆的新扰动

讨论Banach空间中无界闭算子的线性斜投影广义逆的稳定性问题,利用T有界及广义Neumann引理给出了新的扰动定理.     

具有依赖状态脉冲摄动微分系统的稳定性

主要研究具有依赖状态脉冲摄动微分系统的各种稳定性,并利用具有依赖状态脉冲摄动微分系统的新的比较定理得到了脉冲摄动微分系统的稳定性、渐近稳定性和一致渐近稳定性．     

n阶线性微分系统的广义反射矩阵与周期解

利用Mironenko的反射函数理论,讨论了n阶线性微分系统的广义反射矩阵并由此得到n阶周期线性系统及与之等价的非线性微分系统的周期解的存在性和稳定性的判定方法.     

二阶线性矩阵微分系统的振动准则

本文利用广义Riccati变换,研究了一类二阶线性矩阵微分系统的振动性,得到了这类系统振动的若干新的判别准则.     

Existence,uniqueness and stability results of random impulsive semilinear differential systems

In this paper, we consider semilinear differential systems with random impulses. We study the existence and uniqueness of the solutions by relaxing the linear growth conditions, sufficient conditions for stability through continuous dependence on initial conditions and the exponential stability of this system have been established.     

On the solution of boundary value problems with nonseparated multipoint and integral conditions

We suggest a numerical method for solving systems of linear nonautonomous ordinary differential equations with nonseparated multipoint and integral conditions. By using this method, which is based on the operation of convolution of integral conditions into local ones, one can reduce the solution of the original problem to the solution of a Cauchy problem for systems of ordinary differential equations and linear algebraic equations. We establish bounded linear growth of the error of the suggested numerical schemes. Numerical experiments were carried out for specially constructed test problems.     

Comparative exponential dichotomies and column diagonal dominance

It is shown that the dichotomy obtained by Lazer for diagonally dominant linear systems is a weaker condition than that of exponential dichotomy but that the two conditions are equivalent in the case of bounded coefficients. Thus Fink's result that exponential decay of all solutions implies exponential dichotomy does not extend to the case of mixed growth and decay. It is also shown that column dominant systems of mixed sign admit exponential dichotomies when the coefficients are bounded.     

The reducibility of differential equations with impulses in the space of bounded numerical sequences

The analogue of Erugin's theorem is considered for differential equations with impulses in the space of bounded numerical sequences. Sufficient conditions are given for the reduction of the problem regarding the reducibility of the equations of the indicated form with periodic coefficients to the case of finite-dimensional systems of periodic impulse equations of increasing dimensions.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 42, No. 10, pp. 1376–1382, October, 1990.     

Stability properties of nonlinear stochastic impulsive systems with time delay

This article establishes mean square stability and stabilization for stochastic delay systems with impulses. Using Razumikhin methodology, two approaches, classical Lyapunov-based method and comparison principle, are proposed to develop sufficient conditions that guarantee the stability and stabilization properties. It is shown that if the continuous system is stable and the impulses are destabilizing, the impulses should not be applied frequently. On the other hand, if the continuous system is unstable, but the impulses are stabilizing, the impulses should occur frequently to compensate the continuous state growth. Numerical examples are also presented to clarify the proposed theoretical results.     

On Russell's method of controllability via stabilizability

Russell has observed that a linear system is controllable provided it is stabilizable in both positive and negative time. We give a version of this result valid for nonlinear systems, and illustrate its use by giving new proofs of two classical results from control theory, the first involving bounded perturbations of controllable linear systems, and the second involving controllability of linear systems by bounded controls.This research was supported by the Natural Sciences and Engineering Research Council of Canada.     

Invariance of deficiency indices under perturbation for discrete Hamiltonian systems

This paper deals with discrete Hamiltonian systems with one singular endpoint. Using Hermitian linear relation generalized by linear Hamiltonian system, the invariance of the minimal and maximal deficiency indices under bounded perturbation for discrete Hamiltonian systems is built. This parallels the well-known results for linear Hamiltonian differential systems obtained by F.V. Atkinson.     

线性系统的纯点谱和弱Lyapunov相似

本文引入了线性系统的弱Ｌｙａｐｕｎｏｖ相似的概念，并且得到：具有纯点谱的有界线性系统弱Ｌｙａｐｕｎｏｖ相似于常系数对角线线性系统．     

Relative controllability of delay differential systems with impulses and linear parts defined by permutable matrices

This paper investigates the relative controllability of delay differential systems with linear impulses and linear parts defined by permutable matrices. We use the impulsive delay Grammian matrix to discuss the relatively controllability of impulsive linear delay controlled systems and we use the Krasnoselskii's fixed point theorem to discuss the relatively controllability of impulsive semilinear delay controlled systems. Finally, two examples are presented to illustrate our theoretical results.     

具有时滞的一般型脉冲神经网络的指数稳定性

讨论具有时滞的一般性脉冲神经网络的稳定性.在不假定激励函数有界或可导的前提下,利用非光滑分析和Lyapunov泛函,得到了这类神经网络系统平衡点的存在唯一性和全局指数稳定性判别准则.作为特例,得到了Hopfield神经网络,时滞细胞神经网络,双向联想记忆神经网络的平衡点的存在唯一性和全局指数稳定性判定定理.