Volume 23, No. 2 (2013)

A GENERAL COMMON FIXED POINT THEOREM FOR WEAKLY COMMUTING PAIRS OF TYPE (KB)

ABDELKRIM ALIOUCHE(1) and VALERIU POPA(2)

We prove a general coincidence and a common fixed point theorem for two pairs of hybrid mappings satisfying an implicit relation using the concept of weak commutativity of type (KB) which generalizes Theorem 2 of S. Sharma and D. Bhavana, Common fixed point theorem for hybrid pairs of mappings with some weak conditions, Fasc. Math. 39(2008), Theorem 3 of I. Kubiaczyk and D. Bhavana, Noncompatibility, Discontinuity in Consideration of Common Fixed Point of Set and Single Valued Maps, Southeast Asian Bull. Math. 32 (2008) and a theorem of M. A. Ahmed, Common fixed point theorems for set valued and single valued mappings, Demonstr. Math. 36(2)(2003).

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A - EXPANSION CONTINUOUS MAPS AND (A ; B) - WEAKLY CONTINUOUS MAPS IN HEREDITARY GENERALIZED TOPOLOGICAL SPACES

A. AL-OMARI(1), M. RAJAMANI(2) and R. RAMESH(3)

In this paper, we introduce and study A -expansion continuous maps, closed B -continuous maps, (A ; B) -weakly continuous maps and closed (A ; B) -continuous maps in hereditary generalized topological spaces. We, also present several results including de-compositions of (μ,λ)-continuity and (A,Id)-weakly continuity.

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ON α -S-CLOSED CRISP SUBSETS OF A FUZZY TOPOLOGICAL SPACE

ANJANA BHATTACHARYYA(1) and M. N. MUKHERJEE(2)

In this paper, we introduce a new type of covering property in a fuzzy topological space X, called the property of α-s-closedness of subsets of X. We characterize α-s-closed subsets in many ways, e.g. by means of ordinary nets and power-set filterbases.

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SOME PROPERTIES OF UPPER/LOWER ω -CONTINUOUS MULTI-FUNCTIONS

C. CARPINTERO(1), N. RAJESH, E. ROSAS(2) and S. SARANYASRI(3)

The aim of this paper is to introduce and study upper and lower almost ω-continuous multifunctions as a generalization of upper and lower ω-continuous multifunctions, respectively due to Zorlutuna, I. Zorlutuna, ω-continuous multifunctions, Filomat 27(1)(2013).

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INVARIANT APPROXIMATION FOR NONCOMMUTING PAIRS OF SELF-MAPPINGS

SUMIT CHANDOK(1) and T. D. NARANG(2)

The existence of common fixed points of best approximation for noncommuting pairs with different types of nonexpansive mappings have been proved. We also obtain some results on common fixed points from the set of best simultaneous approximation for a map T which is asymptotically (G,S)-nonexpansive where (T,G) and (T,S) are not necessarily commuting pairs. The proved results generalize and extend several known results on the subject.

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FIXED POINT THEOREM FOR CYCLIC (μ,ψ,φ)- WEAKLY CONTRACTIONS

SUMIT CHANDOK(1) and VALERIU POPA(2)

In this article, we introduce the notion of cyclic (μ,ψ,φ)-weakly contraction and derive the existence of fixed point for such mappings in the setup of complete metric spaces. Our result extend and improve some fixed point theorems in the literature.

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NONEXPANSIVE OPERATORS ASSOCIATED TO A SYSTEM OF INTEGRAL EQUATIONS WITH DEVIATING ARGUMENT

MONICA LAURAN

In this paper we shall establish two results on the existence in C_{L}([a,b];[a,b]²) of the solutions of a system of iterative integral equations. The main tools used in our study are the nonexpansive operator technique and Schauder's fixed point theorem.

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SOME FIXED POINT THEOREMS FOR T-KANNAN CONTRACTIONS AND WEAKLY COMPATIBLE PAIRS OF MAPPINGS IN G-CONE METRIC SPACES

ANJU PANWAR(1), RENU CHUGH(2) and SEEMA MEHRA(3)

In the framework of G-cone metric spaces introduced by I. Beg, M. Abbas and T. Nazir , Generalized cone metric spaces, J. Nonlinear Sci. Appl. 3 (1) (2010), we prove several fixed point theorems for mappings satisfying T-Kannan, respectively T-Chaterjea contractive conditions, as well as for weakly commuting pair of mappings satisfying contractive conditions. Our results extend and improve similar results that are known in cone metric spaces.

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SEQUENCE SPACES DEFINED BY A SEQUENCE OF MODULUS FUNCTIONS

KULDIP RAJ(1) and AJAY K. SHARMA(2)

In the present paper we introduce some new sequence spaces defined by a sequence of modulus functions F=(f_{k}). We study some topological properties and inclusion relations between these spaces.

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PSEUDO STRONGLY θ-CONTINUOUS FUNCTIONS

DAVINDER SINGH

A new class of functions called 'pseudo strongly θ-continuous' functions is introduced. Their place in the hierarchy of variants of continuity which already exist in the literature is highlighted. The interplay between topological properties and pseudo strong θ-continuity is investigated.

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