一类非线性时滞偏差分方程正解的不存在性

本文研究了一类非线性时滞偏差分方程正解的不存在性,得到了方程不存在 正解的判据。     

全空间上一类非齐次椭圆方程正解的衰减

本文研究了非齐次椭圆方程不同衰减正解的存在性和衰减问题.利用上下解方法,得到了两个有着不同衰减的正解的存在性,推广了文献[2]中非齐次方程正解的存在性.     

中立型时滞逻辑斯谛方程无界正解的振动性

关于中立型逻辑斯谛方程有界正解的研究已有了长足的发展,而无界正解的研究在已有文献中却非常少见。本文利用振动性原理,结合分析方法得到其无界正解的渐近行为,由此建立中立型时滞逻辑斯谛方程无界正解振动的充分与必要条件,所获结果推广了相关文献的结论。     

一类具p-Laplacian算子三阶m点边值问题的三个正解

考察了一类具p-Laplacian算子三阶m点边值问题的三个正解.首先利用二阶m点边值问题的Green函数把该类问题转化为一个等价的积分方程,在适当的锥上应用Avery-Peteron不动点定理讨论该类积分方程的正解存在性,从而得到了正解存在的充分条件.     

三阶非线性非自治中立型时滞差分方程正解存在性定理

研究了一类三阶非线性变系数非自治中立型变时滞差分方程正解的存在性,给出了该类方程存在最终正解的几个充分条件,推广了已有文献的某些结果.     

带参数时滞Laplacian型方程边值问题的正解

利用锥拉伸与锥压缩不动点定理,研究了一类带参数和时滞的Laplacian型方程边值问题的正解,得到了多个正解存在的充分条件.所得结论拓展了时滞方程的研究领域,为时滞方程的研究带来了动力与活力.     

中立型时滞差分方程的振性与正解存在性

本文研究了一类中立型时滞差分方程的振动性和正解存在性，获得了该方程所有解振动的“Sharp”条件及存在正解的一个充分条件．     

算子方程AX-XA*=B的正解与实正解

利用算子矩阵分块技巧和算子的广义逆,在A是幂等算子的情况下,给出了算子方程AX-XA＊=B有正解和有实正解的充要条件,并给出了正解和实正解的通式。     

非线性一维p-Laplace方程的两正解存在定理

考察了一类非线性一维p-Laplace方程正解的多解性.主要结论表明,即使非线性项在0点和无穷远处不满足通常的增长条件,该方程仍可能有两个正解.     

二阶非线性中立型时滞差分方程的正解

本文研究了一类二阶非线性中立型时滞差分方程的正解,得到了最终正解的存在性判据及存在正解的必要条件,建立了一些正解不存在性定理,所得结论推广并改进了已知的一些结果。     

一般Lidstone边值问题的n个正解的存在性

考察了含所有偶数阶导数的一般Lidstone边值问题的正解和对称正解.通过 选择合适的Banach空间和锥,对该问题建立了n个正解或者对称正解的存在性,其 中n是一个任意的自然数.基本工具是等价范数和锥拉伸与锥压缩型的Krasnosel'skii 不动点定理. 结论的主要条件是局部的.换言之,如果非线性项f在某些有界集上的 "高度"是适当的,则该问题可以具有n个正解.     

二阶非线性微分方程组多点边值问题的正解

该文使用不动点指数理论,研究二阶奇异非线性微分方程组多点边值问题的正解和多个正解的存在性.给出某些保证解的存在性的极限条件,这些条件适用于较一般的函数.     

Existence and multiplicity of positive solutions to Schrödinger–Poisson type systems with critical nonlocal term

The existence, nonexistence and multiplicity of positive radially symmetric solutions to a class of Schrödinger–Poisson type systems with critical nonlocal term are studied with variational methods. The existence of both the ground state solution and mountain pass type solutions are proved. It is shown that the parameter ranges of existence and nonexistence of positive solutions for the critical nonlocal case are completely different from the ones for the subcritical nonlocal system.     

Reduced solutions of Douglas equations and angles between subspaces

In this paper we study some particular solutions of Douglas type equations by means of generalized inverses and angles. We apply this result to characterize positive solutions and some special projections which are symmetrizable for a semidefinited positive bounded linear operator.     

Lazer–Leach type conditions on periodic solutions of semilinear resonant Duffing equations with singularities

In this paper, we study the existence of positive periodic solutions of resonant Duffing equations with singularities. Some Lazer–Leach type conditions are given to ensure the existence of positive periodic solutions of singular resonant Duffing equations.     

含任意次正幂项的广义五阶KdV方程的精确解

利用齐次平衡原理,通过引进含非线性辅助微分方程（sub-ODE）,获得了含任意次正幂项的广义五阶KdV方程的精确解,包括钟状孤波解,扭状孤波解和三角函数表示的周期波解.所得精确解与前人用其它方法所获得一致,并包含了以往文献未提供的部分解,扩充并完善了以往文献的相关结果.     

Positive periodic solutions of impulsive functional differential equations

We study the existence and nonexistence of positive periodic solutions of a non-autonomous functional differential equation with impulses. The equations we study may be of delay, advance or mixed type functional differential equations and the impulses may cause the existence of positive periodic solutions. The methods employed are fixed-point index theorem, Leray-Schauder degree, and upper and lower solutions. The results obtained are new, and some examples are given to illustrate our main results.     

一类无穷时滞周期Lotka-Volterra型系统的正周期解

该文研究一类无穷时滞周期Ｌｏｔｋａ Ｖｏｌｔｅｒｒａ型系统正周期解的存在性．应用Ｓｃｈａｕｄｅｒ不动 点定理得到了一个比较一般的正周期解存在定理．文献［１,２］中的主要结果被改进和推广．     

Sobolev type embedding and weak solutions with a prescribed singular set

New Sobolev type embeddings for some weighted Banach spaces are established. Using such embeddings and the singular positive radial entire solutions, we construct singular positive weak solutions with a prescribed singular set for a weighted elliptic equation. Our main results in this paper also provide positive weak solutions with a prescribed singular set to an equation with Hardy potential.     

Nonexistence and existence of positive solutions for the Kirchhoff type equation

In this paper, we study the nonexistence and existence of positive solutions for the Kirchhoff type equation with nonlinearity having prescribed asymptotic behavior. Because of the structure of our equation, our nonexistence results have some special properties, and our conditions for positive solutions are also different from the existing results.