Charpit System of Partial Differential Equations with Algebraic Constraints

In this paper the Charpit system of partial differential equations with algebraic constraints is considered. So, first the compatibility conditions of a system of algebraic equations and also of the Charpit system of partial differential equations are separately considered. For the combined system of equations of both types sufficient conditions for the existence of a solution are found. They lead to an algorithm for reducing the combined system to a Charpit system of partial differential equations of dimension less than the initial system and without algebraic constraints. Moreover, it is proved that this system identically satisfies the compatibility conditions if so does the initial system.     

关于一类中立型偏微分方程

本文研究了一类一阶脉冲中立型偏泛函微分方程mild解的存在性和唯一性,改进并推广了文[11]的结果。     

关于某些非线性偏微分方程的准确解

以分层理论为基础，对偏微分方程给以一种全新的分类．     

偶数阶拟线性中立型偏微分方程系统的振动性定理

获得了一类偶数阶拟线性偏泛函微分方程系统振动的若干充分条件.     

On the Convergence of Formal Solutions of a System of Partial Differential Equations

We study a version of the classical problem on the convergence of formal solutions of systems of partial differential equations. A necessary and sufficient condition for the convergence of a given formal solution (found by any method) is proved. This convergence criterion applies to systems of partial differential equations (possibly, nonlinear) solved for the highest-order derivatives or, which is most important, “almost solved for the highest-order derivatives.”     

一类高阶中立型偏微分方程组解的振动性

In this paper, sane sufficient conditions are obtained for the oscillation for solutions of systems of high order partial differential equations of neutral type.     

偶数阶时滞偏微分方程组解的振动性定理

本文获得了一类偶数阶时滞偏泛函微分方程组解振动的若干充分条件     

脉冲时滞抛物型偏微分方程组解的振动性

研究一类脉冲时滞抛物型偏微分方程组解的振动性,利用一阶脉冲时滞微分不等式获得了该类方程组在两类不同边值条件下所有解振动的若干充分条件.所得结果充分反映了脉冲和时滞在振动中的影响作用.     

Global Meromorphic Solutions of Partial Differential Equations

In this paper, we survey some recent progress on analytic theory of partial differential equations.     

On the Partial Equiasymptotic Stability in Functional Differential Equations

A system of functional differential equations with delay dz/dt = Z(t, z_t), where Z is the vector-valued functional is considered. It is supposed that this system has a zero solution z = 0. Definitions of its partial stability, partial asymptotical stability, and partial equiasymptotical stability are given. Theorems on the partial equiasymptotical stability are formulated and proved.     

Stochastic Partial Differential Equations on Manifolds~II. Nonlinear Filtering

The conditional law of an unobservable component x(t) of a diffusion (x(t),y(t)) given the observations {y(s):s[0,t]} is investigated when x(t) lives on a submanifold of . The existence of the conditional density with respect to a given measure on is shown under fairly general conditions, and the analytical properties of this density are characterized in terms of the Sobolev spaces used in the first part of this series.     

偏微分方程的调和分析方法简介

本文致力于阐述调和分析与现代偏微分方程研究的关系,特别是奇异积分算子、拟微分算子、Fourier限制性估计、Fourier频率分解方法在椭圆边值问题、非线性发展方程研究中的重要作用.对于偏微分方程研究的各种方法进行了比较与分析,指出了偏微分方程的调和分析方法的优点与局限性.与此同时,还给出了偏微分方程的调和分析方法这一领域的最新研究进展.     

用两个V函数判别泛函微分方程的完全渐近稳定性

本文用两个李雅普诺夫V函数对泛函微分方程建立了完全渐近稳定性的一类判别条件。     

非线性脉冲时滞抛物型偏微分方程的强迫振动性

考虑一类具强迫项的非线性脉冲时滞抛物型偏微分方程，利用脉冲时滞微分不等式，获得了该类方程的解强迫振动的若干充分判据。     

具非线性扩散系数的中立双曲型偏微分方程系统解的振动定理

考虑一类具非线性扩散系数的中立双曲型偏微分方程系统解的振动性.利用Green公式和Riccati变换,获得了该方程组在两类不同边值条件下振动的若干充分条件.     

关于泛函微分方程的完全渐近稳定性定理

本文用两个李雅普诺夫V函数对泛函微分方程建立了完全渐近稳定性的一类判别定理.     

从超布朗运动到随机偏微分方程

随机偏微分方程(SPDE)是目前国内外广泛关注研究进展迅速的一个活跃的学术研究领域.该主题的研究涉及概率论(随机分析、随机场)、偏微分方程、调和分析等诸多分支学科方向.特别是随机偏微分方程其背景更多地源于现代物理学、化学、生物学、经济学等应用性学科,这使得该领域的研究显示出较强的意义和活力.本文从超布朗运动研究出发,发展性地提出有较强背景意义的典型类随机偏微分方程,并进而过渡到一般及更广泛类的随机偏微分方程的研究.同时我们系统地总结了关于高阶随机偏微分方程和随机波动方程的研究成果.