高阶非线性波动方程的有限差分方法

本文研究一类广泛的高阶非线性波动方程组初边值问题的有限差分格式，用离散泛函分析方法和先验估计的技巧得到了有限差分格式的收敛性。     

非线性边界条件下二阶奇异差分方程的正解

本文我们考虑如下二阶奇异差分边值问题\begin{equation*}\begin{cases}-\Delta^{2} u(t-1)=\lambda g(t)f(u) ,\ t\in [1,T]_\mathbb{Z},\\u(0)=0,\\ \Delta u(T)+c(u(T+1))u(T+1)=0,\end{cases}\end{equation*}正解的存在性. 其中, $\lambda>0$, $f:(0,\infty)\rightarrow \mathbb{R}$ 是连续的,且允许在~$0$ 处奇异.通过引入一个新的全连续算子, 我们建立正解的存在性.     

带有非线性非局部流量边界条件反应扩散方程的有限差分格式

本文考虑如下带有非线性非局部流量边界条件的拟线性抛物型方程     

带非线性边界的非线性双曲型方程的有限元素法分析

带非线性边界的非线性双曲型方程的有限元素法分析李潜（山东师范大学数学系）魏洪（中国人民公安大学科技部）ＴＨＥＦＩＮＩＴＥＥＬＥＭＥＮＴＭＥＴＨＯＤＦＯＲＮＯＮＬＩＮＥＡＲＨＹＰＥＲＢＯＬＩＣＥＱＵＡＴＩＯＮＷＩＴＨＮＯＮＬＩＮＥＡＲＢＯＵＮＤＡＲＹＣ...     

Helmholtz方程有限差分方法概述

文章对最近二十年来Helmholtz方程有限差分方法方面的发展进行了概述.以相位误差为基础,文章分别对一维、二维、三维空间中该方面的研究结果进行了陈述,阐述了各种方法之间的差别与联系,特别展现了在高波数情况下不同差分格式对Helmholtz方程的计算效果,并且对高波数Helmholtz方程有限差分方法研究中现在存在的一些主要困难进行了讨论.     

非线性抛物型方程的二次元有限体积元方法

In this paper, a fully discrete finite volume element method for a class of second order nonlinear parabolic equations is given. Piecewise quadratic trial functions and piecewise constant test functions are used to obtain error estimates. A numerical example is given at, the end to show the feasibility of the method.     

二阶非线性差分方程的振动准则

建立了二阶非线性差分方程△(rn△xn-1) Pn△xn-1 qnf(xn)=0的振动准则，所得定理推广和改进了文献中的结果．     

一类非线性差分方程的振动性

用Riccati变换方法，获得了一类非线性差分方程△[αn△（bn△xn=pnxn-r))] qnf(xn-σ)=0的振动性的一些结果，并对已知结果做了一些有意义的改进。     

非线性中立型差分方程的振动性

本文获得了非线性中立型差分方程Δ（ｙｎ－ｐｎｙｎ－ｋ）＋ｑｎｆ（ｙｎ－ｍ）＝０的所有解振动的几个充分条件。     

非线性时滞反应扩散有限差分方程组的高阶单调迭代方法

对一类非线性时滞反应扩散方程的有限差分方程组建立了一类高阶单调迭代方法.这类方法给出了一个有效的线性迭代算法.迭代序列单调收敛于方程组的唯一解,并且序列的单调性使得每一步迭代都给出了解的改进的上下界.迭代收敛率具有p+2阶,这里p≥1是一个正整数,它依赖于迭代方法的构造.数值结果显示了方法的有效性.     

A FINITE DIFFERENCE METHOD FOR THE HEAT EQUATION WITH A NONLINEAR BOUNDARY CONDITION

This article is concerned with the numerical solution to a parabolic equation with a kind of nonlinear boundary conditions. A difference scheme is constructed by the method of reduction of order on uniform mesh to solve the problem. It is proved that the difference scheme is uniquely solvable and uncon-ditionaUy convergent with the convergence order 2 in both space and time in an energy norm. An effective iterative algorithm is given and a numerical example is presented to demonstrate the theoretical results.     

具非线性边界条件的奇异扩散方程

本文讨论具非线性第二边界条件的一端无界的奇异扩散方程的初边值间题,利用先验估计方法得到的主要结果是:存在唯一的整体光滑解,且解连续依赖于初值．     

Helmholtz方程外边值问题的基于修正的DtN边界条件的有限元方法

本文对于无界区域上的Helmholtz方程研究基于修正的Dirichlet-to-Neumann边界条件(MDtN)的有限元方法,得到了依赖于网格尺寸,MDtN边界条件的位置和MDtN中的级数截断项数的H~1-误差估计和L~2-误差估计.最后通过数值结果验证了误差分析的正确性以及所提方法的有效性.     

具非线性非局部边界条件的一类多孔介质方程解的整体存在与爆破

本文研究了具有非线性非局部边界条件的一类退化型多孔介质方程.利用比较原理和上下解的方法,获得了方程的解是否在有限时刻爆破或整体存在的准则,这些结果表明,权重函数g(x,y)及指数l的大小对于问题解的爆破与否起着关键的作用.最后研究了爆破解的爆破率.     

PROPERTIES OF POSITIVE SOLUTIONS FOR A NONLOCAL NONLINEAR DIFFUSION EQUATION WITH NONLOCAL NONLINEAR BOUNDARY CONDITION

This article deals with the global existence and blow-up of positive solution of a nonlinear diffusion equation with nonlocal source and nonlocal nonlinear boundary condition. We investigate the influence of the reaction terms, the weight functions and the nonlinear terms in the boundary conditions on global existence and blow up for this equation. Moreover, we establish blow-up rate estimates under some appropriate hypotheses.     

方程u_(tt)=u_(xxt)+f(u_x)_x初边值问题的差分法

The finite difference method is considered for the followinginitial-boundary-value problem: arrayllutt=uxxt+f(ux)x, & (x,t) QT, u(x,0) =(x), & x ［0,1］, ut(x,0) = (x), & x ［0,1］, u(0,t) =u(1,t) =0, & t ［0,T］,array. where f(s),(x) and (x) are given functions;QT=［0,1］ ［0,T］. The convergence of the finite difference schemesis verified by discrete functional analysis methods and prior estimationtechniques.     

带广义边界条件的四阶抛物型方程的混合间断时空有限元法

构造具有广义边界条件的四阶线性抛物型方程的混合间断时空有限元格式,利用混合有限元方法将高阶方程降阶,利用空间连续而时间允许间断的时空有限元方法离散方程,证明了离散解的存在唯一性,稳定性和收敛性,并给出数值算例验证了方法的有效性.     

ARTIFICIAL BOUNDARY METHOD FOR BURGERS'''' EQUATION USING NONLINEAR BOUNDARY CONDITIONS

This paper discusses the numerical solution of Burgers' equation on unbounded do-mains. Two artificial boundaries are introduced and boundary conditions are obtained onthe artificial boundaries, which are in nonlinear forms. Then the original problem is re-duced to an equivalent problem on a bounded domain. Finite difference method is appliedto the reduced problem, and some numerical examples are given to show the effectivenessof the new approach.     

ASYMPTOTIC BEHAVIOR OF SOLUTIONS TO THE HEAT EQUATIONS WITH NONLINEAR BOUNDARY CONDITIONS

The purpose of this paper is to investigate the stability and asymptotic behav-ior of the time-dependent solutions to a linear parabolic equation with nonlinear boundarycondition in relation to their corresponding steady state solutions. Then, the above resultsare extended to a semilinear parabolic equation with nonlinear boundary condition by an-alyzing the corresponding eigenvalue problem and using the method of upper and lowersolutions.