某些半线性椭圆方程在环域上的正对径解的存在性

利用锥拉伸与锥压缩型的Krasnosel'skii不动点定理讨论了某些二阶非线性椭圆方程在环域上关于Dirichlet边界条件的正对径解的存在性。通过考察非线性项在有界闭区间上的性质建立了若干正对径解的存在性结论。主要结论不涉及非线性项的超线性增长和次线性增长。当非线性项存在极值并满足适当条件时,主要结论是非常有效的。     

一类半线性椭圆方程的正径向解

本文以关于非线性全连续算子的锥不动点定理为工具，研究半线性椭圆边值问题上Δu λa(|x|)u f(|x|,u)=0(x∈Ω)，u|=0及Δu λf(|x|,u)=0(x∈Ω)，u|=0．在不假定f单调的情况下，本文得出了上述问题存在正径向解的若干充分条件．     

半线性椭圆方程的正解

本文用特征理论及上下解方法,证明了一类半线性椭圆方程边值问题的正解的存在性,同时给出了解的估计.     

Positive Radial Solutions of Some Nonlinear Partial Differential Equations

We consider Dirichlet boundary value problems for a class of nonlinear ordinary differential equations motivated by the study of radial solutions of equations which are perturbations of the p-Laplacian.     

一类半线性积分微分方程初边值问题的爆破解和全局解

本文研究初边值问题的爆破解和全局解，证明了在ｆ的凸性假设和一定的增长性假定下解在有限时刻爆破，而在ｆ的其他假设下证明了全局解的存在性。     

具有半正非线性项的分数阶差分方程组边值问题的正解

该文运用不动点指数研究一类具有半正非线性项的分数阶差分方程组边值问题的正解.     

Stability of Semilinear Delay Equations with Positive Solutions

We prove stability for a semilinear delay equation, whose nonlinearity is majorized by a linear positive operator. The key ingredients are a spectral condition, positivity of solutions to the linear problem, and lattice properties of the Banach space.     

Boundary Regularity for Viscosity Solutions of Fully Nonlinear Elliptic Equations

We provide regularity results at the boundary for continuous viscosity solutions to nonconvex fully nonlinear uniformly elliptic equations and inequalities in Euclidian domains. We show that (i) any solution of two sided inequalities with Pucci extremal operators is C ^{1, α} on the boundary; (ii) the solution of the Dirichlet problem for fully nonlinear uniformly elliptic equations is C ^{2, α} on the boundary; (iii) corresponding asymptotic expansions hold. This is an extension to viscosity solutions of the classical Krylov estimates for smooth solutions.     

Boundary Lipschitz Regularity of Solutions for Semilinear Elliptic Equations in Divergence Form

In this paper, we consider the pointwise boundary Lipschitz regularity of solutions for the semilinear elliptic equations in divergence form mainly under some weaker assumptions on nonhomogeneous term and the boundary. If the domain satisfies C1,Dinicondition at a boundary point, and the nonhomogeneous term satisfies Dini continuity condition and Lipschitz Newtonian potential condition, then the solution is Lipschitz continuous at this point. Furthermore, we generalize this result to Reifenberg ...     

锥上的半线性方程正解的存在性定理及其应用

在不要求正规锥的条件下,利用A-proper半线性算子的不动点指数性质,本文给出了半线性方程正解的存在性结果.作为应用,我们获得了二阶m点共振边值问题正解的存在性.     

Multiple Solutions for a Class of Semilinear Elliptic Equations

We show that for a class of semilinear elliptic equations there are at least three nontrivial solutions. Existence of infinitely many solutions is also shown when the nonlinear term is odd. In our results, the nonlinear term can grow super-critically at infinity.

     

临界情形的非齐次半线性椭圆型方程的多解性

考虑有界区域Ω RN 上非齐次半线性椭圆型方程 -Δu(x) =up(x) λf(x)在齐次混合边值条件 (即第三边值问题 ) u n au Ω =0下正解的存在性 ,其中α ,λ≥ 0 ,p=N 2N- 2 ,N>2 ,f(x) ∈L∞(Ω) .证明了存在常数λ >0 ,当λ∈ (0 ,λ )时 ,上述问题至少存在两个正解     

Regularity of Radial Solutions to the Complex Hessian Equations

In this paper we consider regularities of radial solutions to the degenerate complex Hessian equations. Our results generalize some results for Monge-Ampere equation in [Monn, Math. Ana. 275 （1986）, pp. 501-511] and [Delanoe, J. Diff. Eqn. 58 （1985）, pp. 318-344].     

On Weak Solutions of Stochastic Differential Equations

A new proof of existence of weak solutions to stochastic differential equations with continuous coefficients based on ideas from infinite-dimensional stochastic analysis is presented. The proof is fairly elementary, in particular, neither theorems on representation of martingales by stochastic integrals nor results on almost sure representation for tight sequences of random variables are needed.     

一类半线性椭圆型方程的不适定边值问题的最小极值解

本研究Banach空间L^p(Ω）中一类半线性椭圆型方程的不适定边值问题。运用度量广义逆与Schauder不动点定理证得该问题的最小极值解的存在性，应用Banach空间几何与Sobolev空间的方法，给出小极值解的等价条件。本结果，可应用于奇异最优控制问题。     

具Hardy-Sobolev临界指数的半线性椭圆方程的多解存在性

本文考虑一类具Hardy-Sobolve临界指数的半线性椭圆方程,通过证明局部(P．S．)条件和能量估计,运用伪指标理论得到了这类方程多解的存在性(见文[1-13])．     

半线性椭圆型方程组正解的对称性和单调性

该文讨论了扇型区域上一类半线性椭圆型方程组混合边值问题正解的对称性和单调性．所得结果是文献［1］－［14］的一个推广．     

k-Hessian方程径向解的存在性与多解性

该文主要研究了 k-Hessian方程的Dirichlet问题.利用Leggett-Williams不动点定理,得到了一些关于非平凡径向解的存在性与多解性结论.