跳跃非线性条件下椭圆边值问题的变号解和多解存在性

本文应用Banach空间常微分方程和极大极小理论,特别是相对山路引理研究了零点和无穷远点跳跃非线性条件下椭圆边值问题的变号解和多解,得到新的变号解和多解存在性定理,最后我们得到6个非平凡解的存在性.     

一类四阶非线性椭圆问题变号解的存在性

通过建立一个新空间,在新空间中讨论了一个含Hardy位势的四阶非线性椭圆问题变号解的存在性.在一个环绕定理下,得到了问题变号解的存在性.     

具有变号非线性项的拟线性椭圆方程多解的存在性

利用山路定理研究了具有Dirichlet边值问题-div(|▽u|~(2p-2)▽u/(1+|▽u|~(2p))~(1/2))=λf(x,u)多解的存在性,且非线性项f可以变号.     

二阶非线性差分方程边值问题的多解性与变号解

利用下降流不变集方法并结合变分技巧,本文得到二阶非线性差分方程在Robin边界条件下存在正解、负解以及变号解的充分条件的结果.最后运用相关例子验证定理的可行性.     

四阶方程两点边值问题变号解的存在性

利用一个已有的抽象结论,证明了一类非线性四阶方程两点边值问题变号解的存在性.     

一类周期变号的非线性Schroedinger方程解的存在性

讨论非线性Schroedinger方程-△u q（x）u=λu Q（x）│u│^p-1u x∈R^N的解的存在性,其中q(x),Q(x)满足周期性条件,而且Q（x)变号,λ∈R落在-△ q的谱隙中,1＜p＜N 2/N-2。     

非线性三阶边值问题反对称变号解的无穷可解性

利用Krasnosel′skii不动点定理及延拓正(负)解的方法,证明了一类非线性三阶三点边值问题,当其非线性项满足某些假设条件时,具有无穷多个反对称变号解.     

一致椭圆型算子边值问题变号解的存在性

利用Banach空间锥理论、算子的指数理论、上下解理论研究了含有一致椭圆型算子的椭圆边值问题变号解的存在性,同时分别得到了一个正解和一个负解.特别当非线性项是奇函数时,该边值问题至少存在一个正解,一个负解和两个变号解.     

抽象空间中非线性算子方程变号解的存在性研究

利用Banach空间中的锥理论和不动点定理讨论了非线性算子方程变号解的存在性,给出了E_u_0空间下非线性算子方程变号解至少有一个变号解、一个正解和一个负解的条件,并讨论了仅通过一个上解条件得出非线性算子方程变号解的存在性定理.     

非线性算子方程变号解的存在性及其应用

本文利用锥理论讨论了非线性算子方程变号解的存在性,并将抽象结果应用于Sturm-Liouville两点边值问题。所得结果无论在理论上还是在应用上都是新的.     

Sign-Changing and Multiple Solutions Theorems for Semilinear Elliptic Boundary Value Problems with Jumping Nonlinearities

In this paper, we use the ordinary differential equation theory of Banach spaces and minimax theory, and in particular, the relative mountain pass lemma to study semilinear elliptic boundary value problems with jumping nonlinearities at zero or infinity, and get new multiple solutions and sign-changing solutions theorems, at last we get up to six nontrivial solutions. Received April 21, 1998, Revised November 2, 1998, Accepted January 14, 1999     

Sign-Changing Solutions and Multiple Solutions Theorems for Semilinear Elliptic Boundary Value Problems with a Reaction Term Nonzero at Zero

In this paper, we use the ordinary differential equation theory of Banach spaces and minimax theory, in particular, the local mountain pass lemma to study asymptotically linear and superlinear elliptic boundary value problems with a reaction term nonzero at zero, and get new multiple solutions and sign-changing solutions theorems. Moreover, the sign-changing solutions change sign exactly once under some conditions.     

Fucik Spectrum, Sign-Changing, and Multiple Solutions for Semilinear Elliptic Boundary Value Problems with Resonance at Infinity

In this paper, we use Fucik spectrum, ordinary differential equation theory of Banach spaces to study semilinear elliptic boundary value problems with jumping nonlinearities at zero or infinity, especially with resonance at infinity, and obtain new results on the existence of multiple solutions and sign-changing solutions with a weakening of the P.S. condition. In one case we get up to seven nontrivial solutions. The techniques have independent interest.     

具有不连续非线性项和Robin边值条件的半线性椭圆型方程解的多重性

该文基于Banach空间,利用非光滑局部环绕方法考虑有界区域上具有不连续非线性项和Robin边值条件的半线性椭圆型方程解的存在性和多重性.     

Multiple Solutions of Semilinear Elliptic Problems with Degenerate Boundary Conditions

The purpose of this paper is to study a class of semilinear elliptic boundary value problems with degenerate boundary conditions which include as particular cases the Dirichlet and Robin problems. The approach here is distinguished by the extensive use of the ideas and techniques characteristic of the recent developments in the theory of partial differential equations. By making use of the Leray–Schauder degree, we prove very exact results on the number of solutions of our problem. The results here extend earlier theorems due to Berger–Podolak, Castro–Lazer and Ambrosetti–Mancini to the degenerate case.     

脉冲三点边值问题的变号解

本文首先使用拓扑度和不动点指数方法,得到了关于抽象空间中算子方程变号解及多个变号解存在的几个结果,然后将所得结果应用于一类含脉冲三点边值问题,得到了变号解及多个变号解的存在性结果.     

Multiple Positive Solutions for Semilinear Elliptic Equations Involving Subcritical Nonlinearities in RN

In this paper, we study how the shape of the graph of a（z） affects on the number of positive solutions of -△v＋μb（z）v=a（z）vp-1＋λh（z）vq-1,inRN.（0.1） We prove for large enough λ,μ〉 0, there exist at least k＋ 1 positive solutions of the this semilinear elliptic equations where 1 ≤ q 〈 2 〈 p 〈 2＊ = 2N/（N-2） forN ≥ 3.