Search results for "PPI"

showing 10 items of 7396 documents

On generalized weakly G-contraction mapping in G-metric spaces

2011

In this paper, we establish some common fixed point results for two self-mappings f and g on a generalized metric space X. To prove our results we assume that f is a generalized weakly G-contraction mapping of types A and B with respect to g.

Discrete mathematicsComputational MathematicsMetric spaceComputational Theory and MathematicsModeling and SimulationInjective metric spaceMetric (mathematics)Metric mapProduct metricContraction mappingIntrinsic metricMathematicsConvex metric spaceComputers & Mathematics with Applications
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Admissible perturbations of alpha-psi-pseudocontractive operators: convergence theorems

2016

In the last decades, the study of convergence of fixed point iterative methods has received an increasing attention, due to their performance as tools for solving numerical problems. As a consequence of this fact, one can access to a wide literature on iterative schemes involving different types of operators; see [2, 4, 5]. We point out that fixed point iterative approximation methods have been largely applied in dealing with stability and convergence problems; see [1, 6]. In particular, we refer to various control and optimization questions arising in pure and applied sciences involving dynamical systems, where the problem in study can be easily arranged as a fixed point problem. Then, we …

Discrete mathematicsDynamical systems theoryIterative methodGeneral Mathematics010102 general mathematicsGeneral EngineeringHilbert spacePerturbation (astronomy)Krasnoselskij type fixed point iterative schemeFixed point01 natural sciences010101 applied mathematicssymbols.namesakeSettore MAT/08 - Analisi Numericaalpha-psi-pseudocontractive operatorFixed point problemSettore MAT/05 - Analisi Matematicaalpha-admissible mappingsymbolsApplied mathematicsIterative approximation0101 mathematicsApplied scienceMathematics
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Common fixed points for discontinuous mappings in fuzzy metric spaces

2008

In this paper we prove some common fixed point theorems for fuzzy contraction respect to a mapping, which satisfies a condition of weak compatibility. We deduce also fixed point results for fuzzy contractive mappings in the sense of Gregori and Sapena.

Discrete mathematicsFuzzy metric spaceGeneral MathematicsFixed pointFixed-point propertyFuzzy logicFuzzy metric spaceLeast fixed pointPoints of coincidenceCommon fixed pointSettore MAT/05 - Analisi MatematicaFixed-point iterationCommon fixed pointDiscontinuous mappingCoincidence pointMathematicsRendiconti del Circolo Matematico di Palermo
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Fixed point results for F-contractive mappings of Hardy-Rogers-type

2014

Recently, Wardowski introduced a new concept of contraction and proved a fixed point theorem which generalizes Banach contraction principle. Following this direction of research, in this paper, we will present some fixed point results of Hardy-Rogers-type for self-mappings on complete metric spaces or complete ordered metric spaces. Moreover, an example is given to illustrate the usability of the obtained results.

Discrete mathematicsGeneral MathematicsInjective metric spaceMetric spaces ordered metric spaces fixed points F-contractions of Hardy-Rogers-typeFixed-point theoremFixed pointFixed-point propertyConvex metric spaceUniform continuitySettore MAT/05 - Analisi MatematicaFréchet spaceContraction mappingMathematicsFilomat
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Further generalization of fixed point theorems in Menger PM-spaces

2015

In this work, we establish some fixed point theorems by revisiting the notion of ψ-contractive mapping in Menger PM-spaces. One of our results (namely, Theorem 2.3) may be viewed as a possible answer to the problem of existence of a fixed point for generalized type contractive mappings in M-complete Menger PM-spaces under arbitrary t-norm. Some examples are furnished to demonstrate the validity of the obtained results.

Discrete mathematicsGeneralizationApplied MathematicsFixed-point theoremType (model theory)Fixed pointMenger PM-spaceFixed-point propertyMenger's theoremfixed pointψ-contractive mappingDifferential geometrySettore MAT/05 - Analisi MatematicaGeometry and TopologyCoincidence pointMathematicsFixed Point Theory and Applications
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A homotopy fixed point theorem in 0-complete partial metric space

2015

We generalize a result of Feng and Liu, on multi-valued contractive mappings, for studying the relationship between fixed point sets and homotopy fixed point sets. The presented results are discussed in the generalized setting of 0-complete partial metric spaces. An example and a nonlinear alternative of Leray-Schauder type are given to support our theorems.

Discrete mathematicsHomotopic mappings multi-valued mappings partial metric spacesGeneral MathematicsHomotopyFixed-point theoremProduct metricFixed pointType (model theory)Nonlinear systemMetric spaceSettore MAT/05 - Analisi MatematicaSettore MAT/03 - GeometriaCoincidence pointMathematics
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Fixed point and homotopy results for mixed multi-valued mappings in 0-complete partial metric spaces*

2015

We give sufficient conditions for the existence of common fixed points for a pair of mixed multi-valued mappings in the setting of 0-complete partial metric spaces. An example is given to demonstrate the usefulness of our results over the existing results in metric spaces. Finally, we prove a homotopy theorem via fixed point results.

Discrete mathematicsHomotopy categoryPartial metric spacefixed pointsApplied MathematicsInjective metric spacepartial metric spaceslcsh:QA299.6-433multi-valued mappingslcsh:AnalysisFixed pointFixed-point propertyIntrinsic metricConvex metric spacen-connectedMetric spaceSettore MAT/05 - Analisi Matematicamulti-valued mappingMetric (mathematics)AnalysisMathematics
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Generalized iterated function systems on the spacel∞(X)

2014

Abstract In the last decades there has been a current effort to extend the classical Hutchinson theory of iterated function systems composed by contractions on a metric space X into itself to more general spaces and infinitely many mappings. In this paper we consider the (countable) iterated function systems consisting of some generalized contractions on the product space X I into X , where I is an arbitrary set of natural numbers. Some approximations of the attractors of the respective iterated function systems are given.

Discrete mathematicsHutchinson operatorMetric spaceIterated function systemCollage theoremApplied MathematicsCountable setContraction mappingTopological conjugacySpace (mathematics)AnalysisMathematicsJournal of Mathematical Analysis and Applications
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On a pair of fuzzy $\varphi$-contractive mappings

2010

We establish common fixed point theorems for fuzzy mappings under a $\varphi$-contraction condition on a metric space with the d_$\infty$-metric (induced by the Hausdorff metric) on the family of fuzzy sets. The study of fixed points of fuzzy set-valued mappings related to the d_$\infty$-metric is useful in geometric problems arising in high energy physics. Our results generalize some recent results.

Discrete mathematicsInjective metric spaceFuzzy mappingT-normFuzzy subalgebraFixed pointCommon fixed pointComputer Science ApplicationsConvex metric spaceIntrinsic metricHausdorff distanceContractive type mappingSettore MAT/05 - Analisi MatematicaModeling and SimulationFuzzy numberCoincidence pointMathematics
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A Structural Theorem for Metric Space Valued Mappings of Φ-bounded Variation

2009

In this paper we introduce the notion of $\Phi$-bounded variation for metric space valued mappings defined on a subset of the real line. Such a notion generalizes the one for real functions introduced by M. Schramm, and many previous generalized variations. We prove a structural theorem for mappings of $\Phi$-bounded variation. As an application we show that each mapping of $\Phi$-bounded variation defined on a subset of $\mathbb{R}$ possesses a $\Phi$-variation preserving extension to the whole real line.

Discrete mathematicsInjective metric spaceextensionstructural theoremTotally bounded space54C35$\Phi$-bounded variation54E35Intrinsic metricmetric space valued mapings variation $Phi$-variation extension structural theorem.metric space valued mappingsUniform normSettore MAT/05 - Analisi MatematicaBounded functionBounded variationGeometry and Topologyvariation26A45Metric differentialReal lineAnalysisMathematics
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