二阶脉冲积微分方程周期边值问题的解

利用上下解和不动点定理，给出了二阶混合型脉冲积微分方程周期边值问题解的存在性。     

一阶带参数的时滞微分方程的边值问题

本文利用上下解和单调迭代法，讨论了带参数的一阶时滞微分方程的边值问题，获得了这类问题极值解的存在性定理．     

二阶脉冲积微分方程周期过值问题的解(英)

利用上下解方法和不动点定理，给出了二阶混合型脉冲积微分方程周期边值问题解的存在性．     

变分方法与反向上下解

本文在非线性方程的下解不小于上解这一条件（即反向上下解条件）下研究了其解的存在性．我们证明了，如果非线性算子方程有变分结构，有一对反向上下解，对应的算子映某个锥入锥并且满足一定的辅助条件，那么这一方程在锥中至少有两个解．另外，本文还研究了反向上下解条件下非线性椭圆边值问题正解的存在性．     

用上下解方法证明时标上四阶四点边值问题解的存在性

考虑时标上四阶四点边值问题,通过运用上下解方法来证明时标上四阶四点边值问题解的存在性.     

Schauder不动点定理在脉冲微分方程解的存在性中的一个应用

本文用Ｓｃｈａｕｄｅｒ不动点定理证明了一类用上下解方法难以解决的脉冲微分方程边值问题解的存在性，改进现有的一些结果。     

负指数的脉冲EMDEN—FOWLER方程奇异边值问题的正解

利用不动点定理得到了脉冲奇异混合边值问题的上下解方法，并且利用此方法得到了负指数的脉冲Emden—Fowler方程奇异混合边值问题正解存在的充分必要条件．     

Banach空间中的一阶脉冲积分-微分方程边值问题

讨论了抽象空间中的一阶脉冲积分-微分方程的边值问题，利用上下解讨论了解的存在性．     

带有"上确界"的非线性脉冲微分方程无穷边值问题

应用上下解方法和单调迭代技术研究了带有上确界的一阶非线性脉冲微分方程无穷边值问题，并获得了其极值解的存在性结果．     

三阶非线性常微方程的周期边值问题

利用上下解方法和Schauder不动点定理研究了三阶微分方程周期边值问题解的存在性．     

Positive solutions of singular Emden–Fowler boundary value problem with negative exponent and multiple impulses

In this paper, we first give the method of lower and upper solutions for the existence of positive solutions to a singular impulsive boundary value problem. Then we obtain a necessary and sufficient condition for the existence of positive solutions of Emden–Fowler singular impulsive boundary value problem by means of the method of lower and upper solutions.     

EXISTENCE OF SOLUTIONS TO A THIRD-ORDER THREE-POINT BOUNDARY VALUE PROBLEM

In this paper,we study the existence of solutions to a third-order three-point boundary value problem.By imposing certain restrictions on the nonlinear term,we prove the existence of at least one solution to the boundary value problem by the method of lower and upper solutions.We are interested in the construction of lower and upper solutions.     

负指数的脉冲EMDEN-FOWLER方程奇异边值问题的正解

利用不动点定理得到了脉冲奇异混合边值问题的上下解方法,并且利用此方法得到了负指数的脉冲Emden-Fowler方程奇异混合边值问题正解存在的充分必要条件.     

上下解反序条件下二阶泛函微分方程Neumann边值问题解的存在性条件

主要利用上下解和单调迭代法,研究了带有N eum ann边界条件的二阶泛函微分方程在上下解反序条件下解的存在性条件.     

On fourth-order elliptic boundary value problems

This paper is concerned with the existence and uniqueness of a solution for a class of fourth-order elliptic boundary value problems. The existence of a solution is proven by the method of upper and lower solutions without any monotone nondecreasing or nonincreasing property of the nonlinear function. Sufficient conditions for the uniqueness of a solution and some techniques for the construction of upper and lower solutions are given. All the existence and uniqueness results are directly applicable to fourth-order two-point boundary value problems.

     

Periodic boundary value problems for first-order impulsive dynamic equations on time scales

This paper deals with the periodic boundary value problem for a class of first-order impulsive dynamic equations on time scales. We introduce a new notion of lower and upper solutions, which extends the classical lower and upper solutions. The existence of extremal solutions is presented by virtue of the method of lower and upper solutions coupled with monotone iterative technique. An example is also included to illustrate the main results.     

含有p-Laplacian算子的四阶奇异边值问题正解的存在性

研究了含p-Laplacian算子的奇异四阶四点边值问题,利用上下解方法与Schauder不动点定理,获得了至少一个C~3[0,1]正解的存在性结果.     

一类时滞反应扩散方程的周期解和概周期解

通过构造上、下控制函数，结合上、下解方法及相应的单调迭代方法研究了一类时滞反应扩散方程，证明了在反应项非单调时，如果一雏边值问题存在一对周期（或概周期）上、下解，则方程一定存在唯一的周期（或概周期）解．并给出了二维边值问题周期（或概周期）解存在唯一性的充分条件．推广了已有的一些结果。     

Monotone iterative method for the second-order three-point boundary value problem with upper and lower solutions in the reversed order

This article introduces a new concept of upper and lower solutions and studies the existence and uniqueness of solutions of second-order three-point boundary value problems with upper and lower solutions in the reversed order. The sufficient conditions for the existence and uniqueness of solutions are obtained by using the monotone iterative method, meantime, the iterative sequence for solving a solution and its error estimate formula under the condition of unique solution are given. Some results of previous literature are extended and improved. A numerical example is also included to illustrate the effectiveness of the proposed results.