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.     

R~1上的线性Fuzzy微分系统

本文在[1]中定义的Fuzzy微积分的基础上,来讨论线性Fuzzy微分系统讨论的基本方法是通过研究(1.1)在每一个坐标空间的投影所得的集映微分方程来研究(1.1)。首先,我们求出了(1.1)的解,然后讨论了该系统的稳定性、能控性及能观性。我们证明了Fuzzy线性系统的上述性质与某个经典线性系统的相应性质互相等价。本文最后论证了,系统(1.1)实质上等价于■_0(R~1)中的Fuzzy微分系统:     

RP~2上二次微分系统的拓扑分类

本文定义实射影平面上二次微分系统,研究 RP~2上无公因式二次向量场的拓扑分类,我们得到它恰有五种不同的拓扑等价类.     

二阶滞后系统的时滞界限

§1.引言 本文考虑当微分系统的零解为渐近稳定时,使得滞后系统的零解仍为渐近稳定的时滞上限τ_0(0<τ_0≤ ∞)。这里系统的参数均为实常数且τ≥0。 这类问题称为微分系统与微分差分系统之间在稳定性问题中的等价性,当时滞上限τ_0= ∞时,系统(1.2)称为无条件稳定的(即系统的零解对任何τ≥0均为渐近稳     

基于应力形式的二维弹性问题的本征展开法

给出求解基于应力形式的二维弹性问题的本征函数展开方法．通过引入适当的状态函数,将该问题的基本偏微分方程等价地转化为上三角微分系统,导出相应的上三角算子矩阵．证明了该矩阵的两个对角块算子均具有规范的正交本征函数系,并得到它们在相应空间中的完备性．此外,基于本征函数系的完备性,应用本征函数展开法给出了二维弹性问题的一般解．     

一类时滞微分系统的周期解

研究了一类具分布时滞的一阶微分系统的周期解的存在性和全局吸引性.先通过利用重合度理论中的Mawhin延拓定理讨论了周期解的存在性,建立了一些判断准则;进而通过构造适当的Lyapunov泛函以及周期解的存在性结果研究了该类时滞微分系统的周期解的全局吸引性,获得了保证其周期解全局吸引的充分性条件.     

一维交替型脉冲微分系统

讨论一维空间中超前型与滞后型交替的脉冲微分系统.首先考虑具常系数的脉冲微分系统平凡解稳定的充分条件;其次研究了具变系数的脉冲微分系统的振动性,并给出了其解的表示式.     

多元函数的可微性

给出了多元函数可微性的等价条件 ;利用这个条件可以简便有效地判别多元函数的可微性     

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．     

变系数线性中立型微分系统的稳定性

<正> 关于微分方程与微分差分方程之间在稳定性理论中的等价性问题,秦元勋教授于1958年提出并偕同刘永清、王联等,对于常系数线性滞后型微分系统进行了研究.最近又在中研究了变系数线性滞后型微分系统的稳定性问题.但关于中立型方程涉及甚少,仅在文[4]中研究过简单的中立型微分差分方程;其实中立型比滞后型要困难一些,因     

微分特征列法在拟微分算子和Lax表示中的应用

微分特征列法用于拟微分算子和非线性发展方程Lax表示的计算.首先,利用微分特征列法和微分带余除法计算拟微分算子的逆和方根,由于不必求解常微分方程组,并将解代入,因此,使得计算得以简化.其次,利用微分特征列法,约化从广义Lax方程和Zakharov-Shabat推出的非线性偏微分方程,并得到相应的非线性发展方程.在Mathematica计算机代数系统上,编写了相关程序,从而可以利用计算机辅助完成一些非线性发展方程Lax表示的计算.     

On One Class of Systems of Differential Equations and on Retarded Equations

We establish a connection between solutions to a broad class of large systems of ordinary differential equations and solutions to retarded differential equations. We prove that solving the Cauchy problem for systems of ordinary differential equations reduces to solving the initial value problem for a retarded differential equation as the number of equations increases unboundedly. In particular, the class of systems under consideration contains a system of differential equations which arises in modeling of multiphase synthesis.     

THE V-FUNCTIONAL METHOD FOR THE STABILITY OF DEGENERATE DIFFERENTIAL SYSTEMS WITH DELAYS

1 IntroductionStability is an important perfermance index of concrete systems such asmanagement systems, power systems, engineering systems and so on. Forthe stability V--functional criterion method of functional differential systems,have had many results in recent years, see) for example, [1] and [2]. Andfor degenerate systems, papers [41-[81 have carefully discussed and given someimportant results. But we note that (see [9]) many concrete systems, besidescontain delay, are degenerate. So, f…     

Classical Symmetry Reductions of the Schwarz–Korteweg–de Vries Equation in 2+1 Dimensions

Classical reductions of a (2+1)-dimensional integrable Schwarz–Korteweg–de Vries equation are classified. These reductions to systems of partial differential equations in 1+1 dimensions admit symmetries that lead to further reductions, i.e., to systems of ordinary differential equations. All these systems have been reduced to second-order ordinary differential equations. We present some particular solutions involving two arbitrary functions.     

微分代数系统的标准型和分支

我们首先把微分代数系统归结为受限微分方程,且讨论了受限微分系统的参数化问题,即系统的状态空间形式。然后,借助于受限系统的状态空间形式,我们得到了受限微分系统平行于常微分方程的线性化问题和Ｈｏｐｆ分支理论问题的有关结果。     

Systems of matrix rational differential equations arising in connection with linear stochastic systems with Markovian jumping

In this paper, a class of systems of matrix nonlinear differential equations containing as particular cases the systems of coupled Riccati differential equations arising in connection with control of some linear stochastic systems is considered.The system of differential equations considered in this paper are converted in a suitable nonlinear differential equation on a finite-dimensional Hilbert space adequately choosen.This allows us to use the positivity properties of the linear evolution operator defined by the linear differential equations of Lyapunov type.Our aim is to investigate properties of stabilizing and bounded solutions of the considered differential equations and to obtain some conditions ensuring the existence of such solutions.Conditions providing the existence of a maximal solution (minimal solution respectively) with respect to some classes of global solutions are presented. It is shown that if the coefficients of the equations are periodic functions all these special solutions (stabilizing, maximal, minimal) are periodic functions, too.Whenever possible the probabilistic arguments were avoided and so the results proved in the paper appear as results in the field of differential equations with interest in themselves.     

微分系统的稳定性

This article deals with the reflecting function of the differential systems.The results are applied to discuss the stability of these differential systems.     

基于一类积分不等式上的中立型时滞微分方程的稳定性

利用一类积分不等式以及参数变易法,Jensen不等式,给出了更为一般的中立型时滞微分系统的Lyapunov稳定性的判别准则,推广和改进了一些文献中有关中立型微分方程的Lyapunov稳定性的结论.     

A DELAY DIFFERENTIAL INEQUALITY

In this paper, we obtain a slight generalization of the celebrated Halanay delay differential inequality[1]. Using this inequality, Liapunov function and vector Liapunov function, we show that our result can be applied to the stability behavior of solutions of some delay differential systems. And also, we attempt to relax some restrictions of dv/dt, which is necessary under Liapunov function's method on the delay differential systems.     

A RESULT OF SYSTEMS OF NONLINEAR COMPLEX ALGEBRAIC DIFFERENTIAL EQUATIONS

In this article, we mainly investigate the behavior of systems of complex differential equations when we add some condition to the quality of the solutions, and obtain an interesting result, which extends Gaekstatter and Laine＇s result concerning complex differential equations to the systems of algebraic differential equations.