Results 1 to 10 of about 106 (96)
Journal of MathematicsWe establish three types of nonlinear fixed point theorems in regular semimetric spaces. First, we generalize Miculescu and Mihail’s result, thereby unifying the Matkowski fixed point theorem and the Istrăţescu fixed point theorem concerning convex ...
Shu-Min Lu, Peng Wang, Fei He
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Subordinate Semimetric Spaces and Fixed Point Theorems
Journal of Mathematics, 2018 We introduce the concept of subordinate semimetric space. Such notion includes the concept of RS-space introduced by Roldán and Shahzad; therefore the concepts of Branciari’s generalized metric space and Jleli and Samet’s generalized metric space are ...
José Villa-Morales
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Characterizations of K- Semimetric Spaces
Sultan Qaboos University Journal for Science, 2003 In this paper, we prove, for a space X, the following are equivalent: 1. X is a D1 space with a regular-Gδ-diagonal, 2. X is a D2 space with a regular-Gδ-diagonal, 3. X is a semi-developable space with Gδ (3) -diagonal, 4. X is a D1-space with a Gδ(3)
Abdul M. Mohamad
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Characterization of ∑-Semicompleteness via Caristi’s Fixed Point Theorem in Semimetric Spaces [PDF]
Journal of Function Spaces, 2018 Introducing the concept of ∑-semicompleteness in semimetric spaces, we extend Caristi’s fixed point theorem to ∑-semicomplete semimetric spaces. Via this extension, we characterize ∑-semicompleteness.
Tomonari Suzuki
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On cyclic relatively nonexpansive mappings in generalized semimetric spaces
Applied General Topology, 2015 In this article, we prove a fixed point theorem for cyclic relatively nonexpansive mappings in the setting of generalized semimetric spaces by using a geometric notion of seminormal structure and then we conclude some results in uniformly convex Banach ...
Moosa Gabeleh
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Quasi-Contraction Maps in Subordinate Semimetric Spaces
AxiomsThroughout this study, we discuss the subordinate Pompeiu–Hausdorff metric (SPHM) in subordinate semimetric spaces. Moreover, we present a well-behaved quasi-contraction (WBQC) to solve quasi-contraction (QC) problems in subordinate semimetric spaces ...
Areej Alharbi +2 more
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On generalizations of some fixed point theorems in semimetric spaces with triangle functions
Frontiers in Applied Mathematics and StatisticsIn the present study, we prove generalizations of Banach, Kannan, Chatterjea, Ćirić-Reich-Rus fixed point theorems, as well as of the fixed point theorem for mapping contracting perimeters of triangles.
Evgeniy Petrov +2 more
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Hutchinson’s theorem in semimetric spaces
Journal of Fixed Point Theory and Applications, 2022 AbstractOne of the important consequences of the Banach fixed point theorem is Hutchinson’s theorem which states the existence and uniqueness of fractals in complete metric spaces. The aim of this paper is to extend this theorem for semimetric spaces using the results of Bessenyei and Páles published in 2017.
Mátyás Kocsis, Zsolt Páles
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On Functions Preserving Products of Certain Classes of Semimetric Spaces [PDF]
Tatra Mountains Mathematical Publications, 2021 Abstract In the paper, we continue the research of Borsík and Doboš on functions which allow us to introduce a metric to the product of metric spaces. We extend their scope to a broader class of spaces which usually fail to satisfy the triangle inequality, albeit they tend to satisfy some weaker form of this axiom.
Lichman, Mateusz +2 more
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Ultrametrics and Complete Multipartite Graphs
Theory and Applications of Graphs, 2022 Let \((X, d)\) be a semimetric space and let \(G\) be a graph. We say that \(G\) is the diametrical graph of \((X, d)\) if \(X\) is the vertex set of \(G\) and the adjacency of vertices \(x\) and \(y\) is equivalent to the equality \(\diam X = d(x, y)\).
Viktoriia Viktorivna Bilet +2 more
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