Fixed Points of Quasi (f,g)-Nonexpansive Multivalued Mapping

Fixed point theorems for hybrid pair of single valued and multivalued R-subweakly commuting maps are proved.     

Coincidences of Lipschitz-Type Hybrid Maps and Invariant Approximation

The aim of this paper is to obtain new coincidence and common fixed point theorems by using Lipschitz-type conditions of hybrid maps (not necessarily continuous) on a metric space. As applications, we demonstrate the existence of common fixed points from the set of best approximations. Our work sets analogues, unifies and improves various known results existing in the literature.     

Generalized I-Contractions and Pointwise R-Subweakly Commuting Maps

The existence of common fixed points and invariant approximations for pointwise R- subweakly commuting and compatible maps is established. Our results unify and generalize various known results to a more general class of noncommuting mappings.     

On pointwise <Emphasis Type="Italic">R</Emphasis>-subweakly commuting maps and best approximations

The main purpose of this paper is to prove some common fixed point theorems for pointwise R-subweakly commuting maps on non-starshaped domains in P-normed spaces and locally convex topological vector spaces.As applications,invariant approximation results ale established.This work provides extension as well as substantial improvement of several results in the existing literature.     

Common Fixed Point and Invariant Approximation Results for Gregus Type I-Contractions

A fixed point theorem of Ciric, Diviccaro et al., Fisher and Sessa, Gregus, Jungck, and Mukherjee and Verma is generalized to weakly compatible maps. As applications, common fixed point and approximation results for Gregus type I-contractions are obtained. Our results unify and generalize various known results to the more general classes of noncommuting mappings.     

Common fixed point theorems for hybrid pairs of maps in fuzzy metric spaces

The purpose of this paper is to introduce the notion of common limit range property (CLR property) for two hybrid pairs of mappings in fuzzy metric spaces, and we prove common fixed point theorems using (CLR) property for these mappings with implicit relation. Our results extend some known results to multi-valued arena. Also, we prove common fixed point theorem in fuzzy metric spaces satisfying an integral type.     

Common fixed point theorems for non-self-mappings in metric spaces of hyperbolic type

In this paper, the concept of a pair of non-linear contraction type mappings in a metric space of hyperbolic type is introduced and the conditions guaranteeing the existence of a common fixed point for such non-linear contractions are established. Presented results generalize and improve some of the known results. An example is constructed to show that our theorems are genuine generalizations of the main theorems of Assad, ?iri?, Khan et al., Rhoades and Imdad and Kumar. One of the possible applications of our results is also presented.     

对称空间中具有交换点的自映射族的惟一公共不动点

证明了对称空间中具有交换点的两个自映射满足一定条件时存在惟一公共不动点的定理.     

Best and coupled best approximation theorems in abstract convex metric spaces

In this paper, we first give a best approximation theorem in abstract convex metric spaces. As applications, we then derive some best and coupled best approximations and coupled coincidence point results in normed spaces and hyperconvex metric spaces.     

Best approximation, coincidence and fixed point theorems for quasi-lower semicontinuous set-valued maps in hyperconvex metric spaces

Suppose X is a compact admissible subset of a hyperconvex metric spaces M, and suppose F:XM is a quasi-lower semicontinuous set-valued map whose values are nonempty admissible. Suppose also G:XX is a continuous, onto quasi-convex set-valued map with compact, admissible values. Then there exists an x₀X such that

As applications, we give some coincidence and fixed point results for weakly inward set-valued maps. Our results, generalize some well-known results in literature.     

Norm inequalities for vector functions

We study vector functions of Rn into itself, which are of the form x?g(|x|)x, where g:(0,∞)→(0,∞) is a continuous function and call these radial functions. In the case when g(t)=tc for some c∈R, we find upper bounds for the distance of image points under such a radial function. Some of our results refine recent results of L. Maligranda and S.S. Dragomir. In particular, we study quasiconformal mappings of this simple type and obtain norm inequalities for such mappings.     

度量空间中反交换映射的公共不动点

通过引入度量空间中的反交换映射，证明了一个公共不动点定理。这一结果不同于相关的献。     

M-PM空间中反交换映像的公共不动点定理

在M-PM空间中引入了反交换映像的概念,并讨论了映像在反交换条件下的公共不动点的存在性及唯—性问题,同时将此结果推广到Fuzzy度量空间中,改进和推广了若干重要结论.     

Common fixed-points for Banach operator pairs in best approximation

The notion of Banach operator pairs is introduced, as a new class of noncommuting maps. Some common fixed-point theorems for Banach operator pairs and the existence of the common fixed-points of best approximation are presented. These results are proved without the assumption of linearity or affinity for either f or g, which shows that the concept about Banach operator pairs is potentially useful in the study of common fixed-points.     

Some common fixed point theorems for weakly compatible mappings

Jungck's [G. Jungck, Compatible mappings and common fixed points, Int. J. Math. Math. Sci. 9 (1986) 771-779] notion of compatible mappings is further extended and used to prove some common fixed point theorems for weakly compatible non-self mappings in complete convex metric spaces. We improve on the method of proof used by Rhoades [B.E. Rhoades, A fixed point theorem for non-self set-valued mappings, Int. J. Math. Math. Sci. 20 (1997) 9-12] and Ahmed and Rhoades [A. Ahmed, B.E. Rhoades, Some common fixed point theorems for compatible mappings, Indian J. Pure Appl. Math. 32 (2001) 1247-1254] and obtain generalization of some known results. In particular, a theorem by Rhoades [B.E. Rhoades, A fixed point theorem for non-self set-valued mappings, Int. J. Math. Math. Sci. 20 (1997) 9-12] is generalized and improved.     

度量凸空间上非自映射族的唯一公共不动点定理

给出了若干个度量凸空间的闭子集上的非自映射族的公共不动点的存在性与唯一性.我们的主要结果对文献中的许多同类型的不动点定理进行了改进和一般化.     

Common fixed point results for four mappings satisfying almost generalized (S, T)-contractive condition in partially ordered metric spaces

In this paper, we define the concept of almost generalized (S, T)-contractive condition, and prove some common fixed point results for four mappings satisfying almost generalized (S, T)-contractive condition in partially ordered metric space. An example is given to support the usability of our results.     

Generalized I-nonexpansive selfmaps and invariant approximations

Common fixed point results for new classes of noncommuting selfmaps satisfying generalized I-contraction or I-nonexpansive type conditions are established. We apply them to obtain several invariant approximation results which unify, extend, and complement the well-known results.     

Generalized KKM theorems and common fixed point theorems

In this paper, we first prove a generalized KKM theorem, and then use this generalized KKM theorem to establish the generalized equi-KKM theorem, common fixed point theorems for a family of multivalued maps, and the Kakutani-Fan-Glicksberg fixed point theorem. We also show that an existence theorem of the common fixed point theorem is equivalent to the Kakutani-Fan-Glicksberg fixed point theorem.     

Common fixed point theorems for some new generalized contractive type mappings

In this paper, some new generalized contractive type conditions for a pair of mappings in metric space are defined. Some common fixed point results for these mappings are presented.