一类有转向点的奇摄动非线性边值问题的内层性态

研究了一类具有转向点的非线性边界条件下的二阶非线性方程奇摄动问题.在退化方程的解是(Iq)(或(IIn)或(IIIn))稳定等条件下,利用微分不等式理论证明呈内层性态的解的存在性,并给出了解的渐近估计.     

边界条件与占优本征值

本文首先给出了一类算子存在占优本征值的充分条件．接着以板几何中子迁移算子为例，证明了只要在零边界条件下这一充分条件满足，则在常见的非零边界条件下这一条件也满足，因此这一类算子的占优本征值的存在性问题便归结为在零边界条件下充分条件的验证．     

边界条件齐次化辅助函数的统一形式

用分离变量法求解数理方程混合问题时,要求其第一、二、三类边界条件必须是齐次的.若为非齐次的,必须寻求恰当的辅助函数w(x,t),进行变换将其化为齐次的.本文从稳定条件下的线性非齐次边界条件出发,给出了w(x,t)的统一形式,进而将其推广到非稳定条件下的非齐次边界条件,得到w(x,t)的一般的结果.     

非局部边界条件下的抛物型偏微分方程组

本文首先讨论了一个非局部边界条件下的抛物型偏微分方程组,通过一个变量替换,使得在更宽松的边界假设条件下证明了解的存在唯一性;然后讨论了一个完全非线性的抛物型方程组,同样,通过变量替换证明了比较原理.     

非线性边界条件下抛物问题解的爆破

本文讨论在在非线性边界条件下反应-扩散方程解的爆破.当非线性项f,g满足一定的条件时,我们得到其解在有限时间内爆破.     

一类带记忆边界条件波动系统解的长时间性态

研究一类带记忆边界条件波动系统解的长时间性态.在初边值满足一定条件时,利用Faedo-Galerkin近似方法得到了系统解的存在唯一性.使用扰动能量方法,证明了系统解的一致衰减性.     

一类耦合梁方程组在非线性边界条件下解的长时间动力行为（英文）

本文研究一类具有强阻尼项的耦合梁方程组在非线性边界条件下的长时间动力行为,首先利用一些常用不等式和先验估计证明该系统存在唯一的整体解,其次通过证明系统存在有界吸收集和半群的渐近光滑性得到整体吸引子的存在性.     

带有非线性边界条件的拟线性方程组正解的存在性

在这篇文章中,我们讨论了带有非线性边界条件和权函数的的拟线性方程组,主要借助对Nehari流形的分析,在合适的参数条件下得到了方程组至少有两个不同的非平凡正解.     

边界条件含谱参数并具有转移条件的Sturm-Liouville问题的格林函数（英文）

本文在与边界条件有关的修正Hilbert空间中考察一类边界条件含谱参数并具有转移条件的Sturm-Liouville问题.得到了λ为该问题特征值的等价条件,给出了该问题的格林函数.     

板几何中一类具反射边界条件的奇异迁移算子的谱

在L^p（1〈P〈∞）空间上研究板几何中一类具反射边界条件下各向异性、连续能量、均匀介质的奇异迁移方程．证明其奇异迁移算子产生C0半群和该半群的Dyson-Phillips展开式的二阶余项是紧的,且得到了该算子的谱在区域Г中由具有限代数重数的离散本征值组成等结果．     

非局部初值问题解的存在性定理

近来非局部问题的研究日见增多,但涉及带非线性边界条件的初值问题文献 较少.本文目的在于证明一个半线性方程的齐次边值问题和一个非线性边界条件问题 解的存在性.主要使用半群,分数次幂函数空间,广义Poincare算子等工具.     

Theorems about the Existence of Solutions to Problems with Nonlocal Initial Value

Recently much work has been devoted to nonlocal problems. However, very little has been accomplished in the literature for nonlocal initial problems with nonlinear boundary conditions. It is the purpose of this paper to prove the existence results for solutions to a semilinear parabolic PDE with linear homogeneous boundary conditions, and to other ones with nonlinear boundary conditions, provided the ordered upper and lower solutions are given. Semigroup, fractional order function spaces and generalized Poincaré operators play an important role in proving the existence of solutions. Supportedpartly by Research Grant 19531060 of China NSF and Grant 97024811 of the Foundation of Doctoral Program     

Eigenvalues of second-order difference equations with periodic and antiperiodic boundary conditions

This paper is concerned with periodic and antiperiodic boundary value problems for self-adjoint second-order difference equations. Existence of eigenvalues of these two different boundary value problems is proved, numbers of their eigenvalues are calculated, and their relationships are obtained. In addition, a representation of solutions of a nonhomogeneous linear equation with initial conditions is given.     

Stochastic initial boundary value problems subject to distributed and boundary noise and their optimal control

In this paper we consider a class of stochastic evolution equations arising from initial boundary value problems with both boundary and distributed noise. We prove existence and regularity of mild solutions. Then we consider a controlled version of the model and prove the existence of optimal controls and develop the necessary conditions of optimality for partially observed problems using relaxed controls.     

A nonlocal nonlinear diffusion equation in higher space dimensions

We study the initial-value problem for a nonlocal nonlinear diffusion operator which is analogous to the porous medium equation, in the whole RN, N?1, or in a bounded smooth domain with Neumann or Dirichlet boundary conditions. First, we prove the existence, uniqueness and the validity of a comparison principle for solutions of these problems. In RN we show that if initial data is bounded and compactly supported, then the solutions is compactly supported for all positive time t, this implies the existence of a free boundary. Concerning the Neumann problem, we prove that the asymptotic behavior of the solutions as t→∞, they converge to the mean value of the initial data. For the Dirichlet problem we prove that the asymptotic behavior of the solutions as t→∞, they converge to zero.     

Asymptotic of the Solutions of the Initial Boundary Value Problem for the Diffusion Equations for Semiconductors（Ⅱ）

The paper deal with the asymptotic behavior of the solutions to the initial boundary value problem for unipolar drift diffusion equations for semiconductors. Under the proper assumptions on doping profile and initial value, we prove that the smooth solutions to these evolutionary problems tend to the unique stationary solution exponentially as time tends to infinity.     

Global existence,asymptotic stability and blow-up of solutions for the generalized Boussinesq equation with nonlinear boundary condition

In this paper, we consider initial boundary value problem of the generalized Boussinesq equation with nonlinear interior source and boundary absorptive terms. We establish firstly the local existence of solutions by standard Galerkin method. Then we prove both the global existence of the solution and a general decay of the energy functions under some restrictions on the initial data. We also prove a blow-up result for solutions with positive and negative initial energy respectively.     

A nonlocal nonlinear diffusion equation with blowing up boundary conditions

We deal with boundary value problems (prescribing Dirichlet or Neumann boundary conditions) for a nonlocal nonlinear diffusion operator which is analogous to the porous medium equation. First, we prove existence, uniqueness and the validity of a comparison principle for these problems. Next, we impose boundary data that blow up in finite time and study the behavior of the solutions.     

超线性奇异微分方程边值问题的正解

本文研究一类超线性奇异微分方程边值问题,在一定条件下得到C~1[0,1]正解存在的充分条件和必要条件,以及不能有两个可比较C~1[0,1]的正解．最后给出了满足要求的例子．     

半导体中扩散方程初始边界问题的解的渐近性

In this paper, we study the asymptotic behavior of the solutions to the initial boundary value problem for unipolar drift diffusion equations for semiconductors. Under the proper assumptions on doping profile and initial value, we prove that the smooth solutions to these evolutionary problems tend to the unique stationary solution exponentially as time tends to infinity.