SOME GENERALIZATIONS OF KY FAN''''S BEST APPROXIMATION THEOREM

We pressent new Ky Fan type best approximation theorems for a discontinuous multivalued map on metrizable topological vector spaces and hyperconvex spaces. In addition, fixed point results are derived for the map studied. Our work generalizes severl results in approximation theory.     

SOME GENERALIZATIONS OF KY FAN＇S BEST APPROXIMATION THEOREM

We pressent new Ky Fan type best approximation theorems for a discontinuous multivalued map onmetrizable topological vector spaces and hyperconvex spaces. In addition, fixed point results are derivedfor the map studied. Our work generalizes severl results in approximation theory.     

非紧超凸度量空间中的Browder不动点定理及其对重合问题的应用

在非紧超凸度量空间中的非紧允许集上，建立了一个新的Browder不动点定理．作为应用，在非紧超凸度量空间中，研究了Ky Fan截口问题和相交问题，并新建了两个Ky Fan重合定理．     

非紧超凸度量空间中的一个新的不动点定理及其对截口问题和相交问题的应用

In this paper, a new Browder fixed point theorem is established in the noncompact sub-admissible subsets of noncompact hyperconvex metric spaces. As application, a Ky Fan section theorem and an intersection theorem are obtained.     

非紧超凸度量空间中的一个新的不动点定理及其对鞍点问题的应用

In this paper,a new fixed point theorem is established in noncompact hyperconvex metric spaces.As applications,a continuous selection and its fixed point theorem,an existence theorem for maximal elements,a Ky Fan minimax inequality and an existence theorem for saddle points are obtained.     

非紧超凸度量空间中的一个新的不动点定理及其对鞍点问题的应用

在非紧超凸度量空间中建立了一个新的不动点定理.作为应用,研究了连续选择及其不动点定理,极大元定理、Ky Fan极大极小不等式和鞍点定理.     

On certain Matching Properties of Convex Sets

In this paper we use a fixed-point theorem of the Ky Fan typewhich is proved by J.-P. Aubin to give a common generalizationof two matching theorems of Ky Fan concerning closed coveringsof convex sets in topological vector spaces.     

非紧超凸度量空间中的极大元定理及其对极大极小问题和鞍点问题的应用

在非紧超凸度量空间中的非紧次允许子集中建立了一个极大元定理．作为应用,研究了Fan-Browder型不动点定理、KyFan极大极小不等式和鞍点定理．     

Some applications of the Knaster-Kuratowski and Mazurkiewicz principle in hyperconvex metric spaces

In this paper, as applications of the Knaster-Kuratowski and Mazurkiewicz principle in the hyperconvex version, we obtain the Ky Fan type matching theorems for closed and open covers. As applications, some intersection theorems which are hyperconvex versions of corresponding results due to Alexandroff and Pasynkoff, Fan, Klee, Horváth, and Lassonde are established. Then, the Ky Fan type best approximation theorem and Schauder-Tychonoff fixed-point theorem (i.e., Fan-Glicksberg fixed-point theorem) for set-valued mappings in noncompact hyperconvex spaces are also given. Finally, we obtain a general form of the Browder-Fan fixed-point theorem for set-valued mappings in noncompact hyperconvex spaces. These results include corresponding results in the literature as special cases.     

广义度量S-KKM映射的性质及其对变分不等式的应用

引入了超S-γ-广义拟凸（凹）函数,建立了广义度量S-KKM映射与超S-γ-广义拟凸（凹）函数的关系.作为应用,获得了超凸度量空间中的新的KyFan极大极小不等式和鞍点定理.     

广义度量S-KKM映射的性质及其对鞍点问题的应用

引入了S为集盥映射情况下的广义度量S-KKM映射和超S-γ-广义拟凸（凹）函数,建立了广义度量S-KKM映射原理和广义度量S-KKM映射与超S-γ-广义拟凸（凹）函数的关系．作为应用,获得了超凸度量空间中的新的Ky Fan极大极小不等式和鞍点定理．     

Ky Fan Inequalities and Nash Equilibrium Points without Semicontinuity and Compactness

In this paper, a Ky Fan inequality without compactness and semicontinuity assumptions is proved. The inequality is next applied in order to obtain existence results for Nash equilibrium points for two-person games in topological vector spaces and in reflexive Banach spaces.     

紧开覆盖的一个新的Ky Fan型匹配定理及其应用

建立了紧开覆盖的一个新的Ky Fan型匹配定理.作为应用,研究了Fan-Browder型重合定理、Ky Fan型最佳逼近定理、极大元定理及超凸空间中的定性对策和抽象经济的平衡存在定理.     

On the Lower Semicontinuity of the Solution Mappings to Parametric Weak Generalized Ky Fan Inequality

In this paper, we obtain some stability results for parametric weak generalized Ky Fan Inequality with set-valued mappings. Under new assumptions, which are weaker than the assumption of C-strict monotonicity, we provide sufficient conditions for the lower semicontinuity of the solution maps to two classes of parametric weak generalized Ky Fan Inequalities in Hausdorff topological vector spaces. These results extend and improve some results in the literature.     

On Dual Invex Ky Fan Inequalities

In this paper, we obtain some new results for the dual invex Ky Fan inequalities in topological vector spaces. These results can be viewed as an extension and refinement of the previously known results of Noor and others.     

GENERALIZATIONS OF KY FAN＇S THEOREM ON BEST APPROXIMATIONS

In 1969, Ky Fan[3] proved that for any continuous function f from a compact convex subset M of a normed linear space X into X, there exists x ∈ M such that f (x) - x = dist( f (x), M). Since then, there have appeared several generalizations, extensions and applications of this result. This paper also deals with some extensions and generalizations of this result when the underlying spaces are convex metric spaces.     

Generic Uniqueness of Solutions for a Class of Vector Ky Fan Inequalities

This paper is intended mainly to present some generic uniqueness results for a class of vector Ky Fan inequalities. By employing the methods of set-valued analysis, we prove that, in the sense of Baire category, most of the problems in a complete metric space, consisting of vector Ky Fan inequalities satisfying some conditions, have unique solution and that every vector Ky Fan inequality, possessing more than one solution, can be approached arbitrarily by a sequence of vector Ky Fan inequalities each of which has a unique solution. Our discussions are under two different settings. One setting is related to vector Ky Fan inequalities defined on a compact set; the other is related to vector Ky Fan inequalities defined on a noncompact set. The corollaries of our results generalized the corresponding results in the literature.     

On generalized variational inequalities

We obtain a new version of the minimax inequality of Ky Fan. As an application, an existence result for the generalized variational inequality problem with set-valued mappings defined on noncompact sets in Hausdorff topological vector spaces is given. Also, some existence results for the generalized variational inequality problem for quasimonotone and pseudomonotone mappings are obtained. Dedicated to the memory of T. Rapcsák.     

H—度量空间中的广义KKM定理及其应用

定义了一个新的空间-H-度量空间并在H-度量空间中,得到了具有有限度量紧闭（开）值的广义H-KKM映像的广义H-KKM定理,这些定理推广了Khamsi和Yuan最近一系列结果。作为应用,还得到有限度量紧闭（开）覆盖的Ky Fan型匹配定理,不动点定理和极小极大不等式,这些结果统一和推广了近期的许多结果。     

广义Ky Fan点的通有稳定性

得到一个广义的Ky Fan不等式,它以通常的Ky Fan不等式为特例.我们讨论了在一致度量诱导的拓扑结构和二元泛函上方图形的拓扑结构下广义Ky Fan不等式问题构成的空间M中,大多数(在Baire分类意义下)广义Ky Fan不等式问题的所有广义Ky Fan点都是稳定的.