一类具非线性边值条件的双参数奇摄动问题

运用合成展开法,构造了一类具非线性边值条件的双参数奇摄动问题的形式渐近解,并利用微分不等式理论,证明了该问题解的存在性和渐近解的一致有效性.     

一类双参数非线性高阶反应扩散方程的摄动解法

研究了一类两参数非线性反应扩散奇摄动问题的模型.利用奇摄动方法,对该问题解的结构在两个小参数相互关联的情形下作了讨论.首先,构造问题的外部解; 之后在区域的边界邻域构造局部坐标系,再在该邻域中引入多尺度变量,得到问题解的边界层校正项; 然后引入伸长变量,构造初始层校正项,并得到问题解的形式渐近展开式;最后建立了微分不等式理论,并由此证明了问题的解的一致有效的渐近展开式.用上述方法得到的各次近似解,具有便于求解、精度高等特点.     

一类非线性快慢系统非局部问题的摄动解

主要讨论了一类非线性快慢系统非局部问题的摄动解,在适当的条件下,根据不同边界层利用伸长变量和幂级数展开理论,构造了问题的形式渐近解,并利用微分不等式理论在整个区间上证明了形式渐近解的一致有效性,把奇摄动问题的摄动解推广到快慢系统非局部问题的摄动解.     

一类具有边界摄动的非线性非局部反应扩散方程奇摄动问题

研究了一类具有边界摄动的非线性非局部反应扩散方程奇摄动Robin初始边值问题．在适当的条件下,首先求出了原问题的外部解,然后利用伸长变量、合成展开法和幂级数展开理论构造出解的初始层项,并由此得到解的形式渐近展开式．最后利用微分不等式理论,讨论了问题解的渐近性态并导出了几个有关的不等式,讨论了原问题解的存在唯一性和解的一致有效的渐近估计式．     

具有边界摄动弱非线性反应扩散方程的奇摄动

在适当的条件下研究了一类具有边界摄动的非线性反应扩散方程奇摄动初始边值问题．首先,借助正规摄动方法,得到了原问题的外部解．其次,利用伸长变量和幂级数展开理论,构造了解的初始层项．然后,利用微分不等式理论,研究了初始边值问题解的渐近性态．最后,利用一些相关的不等式,讨论了原问题解的存在、唯一性及其一致有效的渐近估计．     

二阶半线性奇摄动边值问题的渐近解

研究不满足法向双曲条件的二阶半线性非自治奇摄动Dirichlet边值问题.首先,利用边界层函数法,构造了问题在两个区间端点的代数边界层,获得了形式渐近解;接着,利用上下解方法,证明了解的存在性、渐近解的一致有效性以及渐近解与精确解之间的误差估计.研究表明:通过对奇异摄动参数进行适当的尺度变换,一定条件下可处理任意退化的二阶半线性非自治奇摄动边值问题.最后,通过一个典型例子验证了理论结果的正确性.     

两参数奇异摄动非线性双曲型微分系统的过渡冲击层广义解

研究了一类两参数双曲型微分系统奇异摄动初始边值问题.首先,利用奇异摄动理论和方法,注意到两个小参数,构造了问题的外部解.其次,利用多重尺度变量和伸长变量,分别得到了原问题解的过渡冲击层、边界层和初始层校正项.最后,得到了原问题解的渐近展开式,并利用泛函分析不动点理论,证明了渐近解的一致有效性.由本方法求得的原问题的渐近解,它还可以进行微分,积分等解析运算,从而能了解相应过渡冲击层解的更进一步的性态.因此本方法具有良好的应用前景.     

两参数非线性高阶椭圆型偏微分方程奇摄动边值问题的解（英文）

讨论了一类具有两参数的非线性高阶椭圆型方程边值问题.在适当的条件下,利用摄动理论和伸长变量构造了原问题解的形式渐近展开式.再利用微分不等式理论,研究了边值问题解的存在性和渐近性态.     

一类双参数奇摄动边值问题的研究

研究了一类双参数高阶非线性奇摄动方程边值问题,利用合成展开法构造出形式渐近解,再利用微分不等式理论证明了解的存在一致有效性.     

具有两参数的奇摄动时滞非线性边值问题的冲击波解(英文)

本文研究一类具有两参数时滞奇摄非线性问题的冲击波解.在适当的条件下,利用匹配法和微分不等式理论,构造原边值问题冲击波奇摄动解并讨论它的渐近性态.     

ASYMPTOTIC SOLUTION TO NONLINEAR REACTION DIFFUSION EQUATION WITH TWO SMALL PARAMETERS

In this paper, a class of nonlinear reaction diffusion singularly perturbed problem with two parameters is studied. Using the singular perturbation method, the structure of solution to the problem is discussed related two small parameters. The asymptotic solution to the problem is given.     

THE ASYMPTOTIC BEHAVIOR OF SOLUTION FOR A CLASS OF STRONGLY NONLINEAR NON-AUTONOMOUS EQUATION

In this paper, using the singularly perturbed theory and the boundary layer corrective method, the asymptotic behavior of solution for a class of strongly nonlinear non-autonomous equations and the infection for asymptotic behavior of the solution with regard to the boundary condition are studied. According to the different regions of the boundary value, the asymptotic expansions of the solution for the original problem are obtained simply and conveniently.     

一类具有摄动边界的弱非线性反应扩散方程

研究了具有摄动边界的非线性反应扩散方程的问题.在适当的条件下,利用微分不等式理论,讨论了问题的渐近解.     

SINGULAR PERTURBATION OF THREE-POINT BOUNDARY VALUE PROBLEM FOR THIRD ORDER DIFFERENTIAL EQUATIONS

In this paper, by the theory of differential inequalities, we study the existence and uniqueness of the solution to the three-point boundary value problem for third order differential equations. Furthermore we study the singular perturbation of three-point boundary value problem to third order quasilinear differential equations, construct the higher order asymptotic solution and get the error estimate of asymptotic solution and perturbed solution.     

A CLASS OF SINGULARLY PERTURBED NONLINEAR BOUNDARY VALUE PROBLEM

The singularly perturbed boundary value problem for the nonlinear boundary conditions is considered. Under suitable conditions,the asymptotic behavior of solution for the original problems is studied by using theory of differential inequalities.     

The Singularly Perturbed Nonlinear Nonlocal Initial Boundary Value Problems for Reaction Diffusion Equations

The singularly perturbed nonlinear nonlocal initial boundary value problem for reaction diffusion equations is discussed. Under suitable conditions, the outer solution of the original problem is obtained. By using the stretched variable, the composing expansion method and the expanding theory of power series the initial layer is constructed. By using the theory of differential inequalities the asymptotic behavior of solution for the initial boundary value problems are studied, and by educing some relational inequalities the existence and uniqueness of solution for the original problem and the uniformly valid asymptotic estimation are considered.     

一类四阶非线性奇摄动方程的边界层问题

本文研究了一类四阶非线性奇摄动方程的边界层问题,利用在左右边界层的两次匹配,得出了原问题解的一致有效的渐近表达式.这个结果是奇摄动理论在研究高阶微分方程中的一个应用.     

THE SOLVABILITY FOR A CLASS OF SINGULARLY PERTURBED QUASI-LINEAR DIFFERENTIAL SYSTEM

The solvability for a class of singularly perturbed Robin problem of quasilinear differential system is considered. Using the boundary layer corrective method the formal asymptotic solution is constructed. And using the theory of differential inequality the uniform validity of the asymptotic expansions for solution is proved.