Stampacchia广义向量拟均衡问题Ⅱ

通过引进锥对角拟凸概念,讨论了Stampacchia广义向量拟均衡问题解的存在性.由于该问题包含了许多形式的变分不等式与均衡问题作为特例,所得解的存在性结果推广和发展了近期的一些研究结果,主要有以下两个方面: 1)放宽了对连续性的要求;2)由数值型推广到了向量型.     

广义集值隐向量变分不等式问题系统解的存在性与稳定性

介绍了广义集值隐向量变分不等式问题系统,并且通过Kakutani-Fan-Glicksberg不动点定理,建立了其解的存在性结果;在此基础上,研究了广义集值隐向量变分不等式问题系统的稳定性,建立了其解集本质连通区的存在性结果.     

拓扑向量空间中的一类平衡问题研究

通过对偶的方法研究了拓扑向量空间上的一类平衡问题,并详细的证明了平衡问题解的存在性结果,又利用集值映射的拟凸性讨论了一类集值映射的平衡问题,并给出了详细的证明过程,得到其平衡问题的解的存在性结果.     

闭凸集上的一类非线性半变分不等式解的存在性

考虑一类定义在闭凸集上的非线性半变分不等式问题,通过运用闭凸集上的临界点理论、Clarke次微分性质以及非光滑紧性条件等,得到了这类半变分不等式解的存在性．     

具集值映射的广义强向量拟均衡问题

讨论了一类具集值映射的广义强向量拟均衡问题（GSVQEP）解的存在性.利用连续选择定理和不动点定理,在没有任何单调性假设下得到了GSVQEP解的存在性定理.     

集值广义强向量拟均衡问题解的存在性

利用集值映射的自然拟C-凸性和集值映射的下(-C)-连续性的定义以及Kakutani-Fan-Glicksberg不动点定理,在不要求锥C的对偶锥C~*具有弱*紧基的情况下,建立了集值广义强向量拟均衡问题解的存在性定理.把相关文献中所得的关于单值映射解的存在性结果推广到了集值映射的情形.     

有序Banach空间非线性Robin边值问题正解的存在性

讨论有序Banach空间E中的非线性Robin边值问题正解的存在性,通过非紧性测度的估计技巧与凝聚映射的不动点指数理论获得该问题正解的存在性结果.     

α凸算子(α>1)的正不动点存在性及其应用

通过构造一个特殊的锥,利用锥拉伸与压缩不动点定理对α凸算子(α>1)正不动点的存在性与不可比较性作了研究,并将其结果应用到超线性多项式型Hammerstein积分方程．     

关于随机一致凸性

致力于随机一致凸性概念的进一步探讨．首先,通过一个特殊的层次剖分指出对任意的随机赋范模而言随机凸性模都有良好定义,从而改进了近期的文献中许多已知的结果．然后,提出并研究了一种与随机一致凸性密切相关的新性质,从一个新的角度阐述了随机一致凸性的复杂性．     

一般化凸空间上的相交定理和一个不等式系

根据文[1]中得到的Ky Fan型重叠定理给出一般化凸空间上的相交定理.作为它的应用讨论一个不等式系的解的存在性问题.我们的结论改进和一般化了相应文献中的结果.     

A topological degree for orbits connecting critical points of autonomous systems

An argument based on topological degree is used to obtain an existence theorem for orbits connecting two critical points of an autonomous system. The result is applied to the existence of viscous profiles approximating shock waves in weak solutions of systems of nonlinear conservation laws. A result for the case where the Morse indices of the two critical points differ by more than one is also obtained.     

Circle action with prescribed number of fixed points

Given any two positive integers k and n, this paper is concerned with the existence of a circle action on a closed, smooth orientable n-dimensional manifold with precisely k isolated fixed points. We first show that this existence problem can be reduced to that of an n-dimensional manifold with exactly three fixed points. Then by using a rigidity result, we determine possible weights on these three fixed points when n = 4.     

Nontrivial periodic solutions for strong resonance Hamiltonian systems via a local linking theorem

In this paper, we first establish an existence result of critical points for a class of functionals defined on Hilbert spaces by using a local linking idea. Then as an application of the existence result, we obtain the existence of periodic solutions of strong resonance Hamiltonian systems which are asymptotically linear both at infinity and at origin.     

Existence of Solution of Minimax Inequalities, Equilibria in Games and Fixed Points Without Convexity and Compactness Assumptions

This paper characterizes the existence of equilibria in minimax inequalities without assuming any form of quasiconcavity of functions and convexity or compactness of choice sets. A new condition, called “local dominatedness property”, is shown to be necessary and further, under some mild continuity condition, sufficient for the existence of equilibrium. We then apply the basic result obtained in the paper to generalize the existing theorems on the existence of saddle points, fixed points, and coincidence points without convexity or compactness assumptions. As an application, we also characterize the existence of pure strategy Nash equilibrium in games with discontinuous and non-quasiconcave payoff functions and nonconvex and/or noncompact strategy spaces.     

A Nash type solution for hemivariational inequality systems

In this paper, we prove an existence result for a general class of hemivariational inequality systems using the Ky Fan version of the KKM theorem Fan (1984) [10] or Tarafdar fixed points Tarafdar (1987) [11]. As application, we give an infinite-dimensional version for the existence result of Nash generalized derivative points introduced recently by Kristály (2010) [5]. We also give an application to a general hemivariational inequality system.     

Best proximity point theorems for cyclic orbital Meir-Keeler contraction maps

We introduce a notion of cyclic orbital Meir-Keeler contraction and give sufficient conditions for the existence of fixed points and best proximity points of such a map. Our main result is a generalization of a best proximity point result due to Di Bari et al. [C. Di Bari, T. Suzuki, C. Vetro, Best proximity points for cyclic Meir-Keeler contractions, Nonlinear Anal. 69 (2008) 3790-3794].     

On a fixed point theorem for the product of operators

In this paper, we study the existence of fixed points for the product of nonlinear operators. This kind of fixed point theorems is necessary in consideration of quadratic differential and integral problems. We emphasize a possible extension of the applicability of obtained theorems and consequently we prove the existence of fixed points for operators acting on some function spaces that are not necessarily Banach algebras. This result can be successfully applied to many quadratic problems.     

On Quasimonotone Variational Inequalities

The purpose of this paper is to prove the existence of solutions of the Stampacchia variational inequality for a quasimonotone multivalued operator without any assumption on the existence of inner points. Moreover, the operator is not supposed to be bounded valued. The result strengthens a variety of other results in the literature.     

An application of a fixed point theorem to best simultaneous approximation

Using a recent result regarding the fixed points of multivalued mappings, the existence of invariant best simultaneous approximation in chainable metric space is proved.