含两参数的三阶拟线性常微分方程边值问题的奇摄动

研究含两参数的三阶拟线性常微分方程奇摄动边值问题.采用两阶段展开的方法,对ε/μ2→0(μ→0);μ2/ε→0(ε→0)和ε=μ2三种情形构造出形式渐近解,同时利用微分不等式方法,证明了解的存在性,并给出余项的一致有效的估计.     

半线性二阶系统的奇异摄动现象*

本文研究半线性二阶系统的奇异摄动现象,在适当的假设下,借助于构造特殊的不变域,证得向量边值问题解的存在及其当ε→0+时的渐近性质,在这种不变域中解呈现所谓的边界层现象和角层现象.     

Singular perturbation of boundary value problem for a vector fourth order nonlinear differential equation

We study the vector boundary value problem with boundary perturbations: ε~2y~((4))=f(x,y,y″,ε, μ) ( μ<χ<1-μ) y(χ,ε,μ)l_(χ-μ)= A_1(ε,μ), y(χ,ε,μ)l_(χ-1-μ)=B_1(ε,μ) y″(χ,ε,μ)l_(χ-μ)=A_2(ε,μ),y″(χ,ε,μ)l_(χ-1-μ)=B_2(ε,μ)where yf, A_j and B_j (j=1,2) are n-dimensional vector functions and ε,μ are two small positive parameters. This vector boundary value problem does not appear to have been studied, although the scalar boundary value problem has been treated. Under appropriate assumptions, using the method of differential inequalities we find a solution of the vector boundary value problem and obtain the uniformly valid asymptotic expansions.     

奇摄动拟线性系统的边界层和角层性质

本文利用微分不等式的方法研究二阶拟线性系统狄立克雷问题解的存在和当ε→0+时它们的渐近性质.根据退化解在(a,b)中是否有连续的一阶偏导数,研究了解的两种渐近形式,从而导出边界层和角层现象.     

Interior layer phenomena of semilinear systems

In this paper,we study the interior layer phenomena of singular perturbation boundaryvalue problems for semilinear systems:εy” = f(t,y.ε)(a0 is a small parameter,y.f. A and B are n-dimensional vector functions.Thisvector boundary value peoblem does not appear to have been studied,although the scalarboundary problem has been treated extensively.Under appopriate assumptions we obtainexistence of solution as in the scalar problem and the estimate of this solution in terms ofappropriate inequalities as well.     

Asymptotic experssion of the solution of general boundary value problem for higher order elliptic equation with perturbation both in boundary and in operator

In this paper basing on (1) and (2), we study the singular perturbation of general boundary value problem for higher order elliptic equation with perturbation both in the boundary and in the operator, so as to establish the asymptotic expression involving two parameters. Thus, the iterative process of finding the asymptotic solution is derived and the estimation of the remainder term is given out, we extend and improve the previously published papers.     

SINGULAR PERTURBATIONS OF ROBIN BOUNDARY VALUE PROBLEMS FOB SEMILINEAR SYSTEMS

In this paper, we study the singular perturbations of Robin boundary value problems for semilinear systems using the method and technique of differential inequalities. We assume that the corresponding reduced system has at least one solution which is Iq -stable. This "component-wise" Iq-stability condition will allow us to obtain estimates for each component of the solution.     

AGAIN DISCUSSING ABOUT SINGULAR PERTURBATION OF GENERAL BOUNDARY VALUE PROBLEM FOR HIGHER ORDER ELLIPTIC EQUATION CONTAINING TWO-PARAMETER

In this paper using the method of "The Two-Variable Expansion Procedure" we again discuss the construction of asymptotic expression of solution of general boundary value problem for higher order ellitptic equation containing two-parameter whose boundary condition is more general than [1]. We give asymptotic expression of solution as well as the estimation corresponding to the remainder term.     

Existence of solutions for a singularly perturbed boundary value problem for the third order semi-linear differential equation with a turning point

In this paper,by using the techniques of differential inequalities,we prove the existence of the solutions of a singularly perturbed boundary value problem for the third order semilinear differential equation with a turning point.     

极限方程为椭圆-抛物的四阶椭圆型方程的奇摄动

本文研究了极限方程为椭圆-抛物的四阶椭圆型方程-ε2Δ2u+ym?2u/?y2+?2u/?x2+a(x,y)?u/?y+b(x,y)?u/?x+c(x,y)=0的奇摄动问题,其中ε为正的小参数,m为正的实数,Δ为拉普拉斯算子,a,b,c充分光滑.在适当的假设下,导出可解性的充分条件,证明了解的存在和给出任意阶的一致有效的渐近解.