0000000000457828

AUTHOR

Cristina Di Bari

showing 24 related works from this author

COMMON FIXED POINTS FOR psi-CONTRACTIONS ON PARTIAL METRIC SPACES

2013

We prove some generalized versions of an interesting result of Matthews using conditions of different type in 0-complete partial metric spaces. We give, also, a homotopy result for operators on partial metric spaces.

Points of coincidence0-complete partial metric spaceSettore MAT/05 - Analisi Matematicapsi-contractionscommon fixed point
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Fixed point, attractors and weak fuzzy contractive mappings in a fuzzy metric space

2005

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Nonlinear quasi-contractions of Ciric type

2012

In this paper we obtain points of coincidence and common fixed points for two self mappings satisfying a nonlinear contractive condition of Ciric type. As application, using the scalarization method of Du, we deduce a result of common fixed point in cone metric spaces.

Common fixed points quasi-contractions scalarization cone metric spaces.Settore MAT/05 - Analisi Matematica
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Common fixed points in cone metric spaces for $MK$-pairs and $L$-pairs

2011

In this paper we introduce some contractive conditions of Meir-Keeler type for a pair of mappings, called $MK$-$pair$ and $L\textrm{-}pair$, in the framework of cone metric spaces and we prove theorems which assure existence and uniqueness of common fixed points for $MK$-$pairs$ and $L \textrm{-}pairs$. As an application we obtain a result of common fixed point of a $p$-$MK$-pair, a mapping and a multifunction, in complete cone metric spaces. These results extend and generalize well-known comparable results in the literature.

$MK$-pairCommon fixed points.Settore MAT/05 - Analisi Matematica$L$-pairCone metric space
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Common Fixed Point Theorems for Weakly Compatible Maps Satisfying a General Contractive Condition

2008

We introduce a new generalized contractive condition for four mappings in the framework of metric space. We give some common fixed point results for these mappings and we deduce a fixed point result for weakly compatible mappings satisfying a contractive condition of integral type.

Discrete mathematicsWeakly compatibleArticle SubjectContractive MapsCommon Fixed Pointlcsh:MathematicsType (model theory)Fixed pointlcsh:QA1-939Metric spaceMathematics (miscellaneous)Settore MAT/05 - Analisi MatematicaCommon fixed pointWeakly Compatible MapCoincidence pointMathematicsInternational Journal of Mathematics and Mathematical Sciences
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Absolute continuity for Banach space valued mappings

2007

We consider the notion of p,λ,δ-absolute continuity for Banach space valued mappings introduced in [2] for real valued functions and for λ = 1. We investigate the validity of some basic properties that are shared by n, λ-absolutely continuous functions in the sense of Maly and Hencl. We introduce the class $δ-BV^p_{λ,loc}$ and we give a characterization of the functions belonging to this class.

Discrete mathematicsClass (set theory)General MathematicsBanach spaceCharacterization (mathematics)Algebra over a fieldAbsolute continuityMathematics
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$varphi$-pairs and common fixed points in cone metric spaces

2008

In this paper we introduce a contractive condition, called $\varphi \textrm{-}pair$, for two mappings in the framework of cone metric spaces and we prove a theorem which assures existence and uniqueness of common fixed points for $\varphi \textrm{-}pairs$. Also we obtain a result on points of coincidence. These results extend and generalize well-known comparable results in the literature.

Cone metric spaces \and $\varphi$-pairs \and Common fixed points \and Coincidence pointsPure mathematicsGeneral MathematicsInjective metric spaceMathematical analysisFixed pointIntrinsic metricConvex metric spaceMetric spaceCone (topology)Settore MAT/05 - Analisi MatematicaMetric (mathematics)Metric mapMathematics
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Primitive rispetto all’ oscillazione

2002

We study the real valued functions having a primitive with respect to the oscillation or a primitive with respect to the oscillation up to anegligible set.

Set (abstract data type)Pure mathematicsOscillationGeneral MathematicsData_MISCELLANEOUSHardware_INTEGRATEDCIRCUITSHardware_PERFORMANCEANDRELIABILITYAlgebra over a fieldMathematicsRendiconti del Circolo Matematico di Palermo
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Weakly \varphi-pairs and common fixed points in cone metric spaces

2009

In this paper we introduce a weak contractive condition, called weakly \varphi-pair, for two mappings in the framework of cone metric spaces and we prove a theorem which ensures existence and uniqueness of common fixed points for such mappings. Also we obtain a result on points of coincidence. These results extend and generalize well-known comparable results in the literature.

Pure mathematicsGeneral MathematicsInjective metric spaceMathematical analysisCoincidence pointsFixed pointConvex metric spaceIntrinsic metricMetric spaceCommon fixed pointCone (topology)Settore MAT/05 - Analisi MatematicaWeakly \varphi-pairCone metric spaceUniquenessCoincidence pointMathematics
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Common fixed points of g-quasicontractions and related mappings in 0-complete partial metric spaces

2012

Abstract Common fixed point results are obtained in 0-complete partial metric spaces under various contractive conditions, including g-quasicontractions and mappings with a contractive iterate. In this way, several results obtained recently are generalized. Examples are provided when these results can be applied and neither corresponding metric results nor the results with the standard completeness assumption of the underlying partial metric space can. MSC:47H10, 54H25.

0-complete spaceDiscrete mathematicsInjective metric spaceApplied Mathematicspartial metric space010102 general mathematicsquasicontraction.common fixed pointEquivalence of metrics01 natural sciencesIntrinsic metricConvex metric space010101 applied mathematicsMetric spacefixed pointSettore MAT/05 - Analisi MatematicaMetric (mathematics)Geometry and Topology0101 mathematicsMetric differentialFisher information metricMathematicsFixed Point Theory and Applications
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Best proximity points for cyclic Meir–Keeler contractions

2008

Abstract We introduce a notion of cyclic Meir–Keeler contractions and prove a theorem which assures the existence and uniqueness of a best proximity point for cyclic Meir–Keeler contractions. This theorem is a generalization of a recent result due to Eldred and Veeramani.

Pure mathematicsGeneralizationApplied MathematicsBest proximity pointMathematics::General TopologyExistence theoremCyclic contractionCyclic Meir–Keeler contractionProximal contractionCyclic contractionSettore MAT/05 - Analisi MatematicaCalculusPoint (geometry)UniquenessAnalysisMathematics
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A remark on absolutely continuous functions in ℝ n

2006

We introduce the notion ofα, λ-absolute continuity for functions of several variables and we compare it with the Hencl’s definition. We obtain that eachα, λ-absolutely continuous function isn, λ-absolutely continuous in the sense of Hencl and hence is continuous, differentiable almost everywhere and satisfies change of variables results based on a coarea formula and an area formula.

Discrete mathematicsChange of variablesContinuous functionGeneral MathematicsAlmost everywhereQuasi-continuous functionCoarea formulaDifferentiable functionAlgebra over a fieldAbsolute continuityMathematicsRendiconti del Circolo Matematico di Palermo
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Some Common Coupled Fixed Point Results for Generalized Contraction in Complex-Valued Metric Spaces

2013

We introduce and study the notion of common coupled fixed points for a pair of mappings in complex valued metric space and demonstrate the existence and uniqueness of the common coupled fixed points in a complete complex-valued metric space in view of diverse contractive conditions. In addition, our investigations are well supported by nontrivial examples.

Discrete mathematicscoupled fixed pointArticle SubjectApplied MathematicsInjective metric spacelcsh:Mathematicscommon coupled fixed pointlcsh:QA1-939Convex metric spaceIntrinsic metricMetric spaceSettore MAT/05 - Analisi MatematicaFixed-point iterationcomplex-valued metric spaceMetric (mathematics)Contraction mappingFisher information metricMathematicsJournal of Applied Mathematics
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Common fixed points in cone metric spaces for CJM-pairs

2011

Abstract In this paper we introduce some contractive conditions of Meir–Keeler type for two mappings, called f - M K -pair mappings and f - C J M -pair (from Ciric, Jachymski, and Matkowski) mappings, in the framework of regular cone metric spaces and we prove theorems which guarantee the existence and uniqueness of common fixed points. We give also a fixed point result for a multivalued mapping that satisfies a contractive condition of Meir–Keeler type. These results extend and generalize some recent results from the literature. To conclude the paper, we extend our main result to non-regular cone metric spaces by using the scalarization method of Du.

Cone metric spaces CJM-pairs Common fixed points Common coincidence points.Injective metric spaceMathematical analysisMathematics::General TopologyFixed pointComputer Science ApplicationsIntrinsic metricConvex metric spaceCombinatoricsMetric spaceCone (topology)Settore MAT/05 - Analisi MatematicaModeling and SimulationUniquenessCoincidence pointMathematicsMathematical and Computer Modelling
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Common fixed points for self-mappings on partial metric spaces

2012

Abstract In this paper, we prove some results of a common fixed point for two self-mappings on partial metric spaces. Our results generalize some interesting results of Ilić et al. (Appl. Math. Lett. 24:1326-1330, 2011). We conclude with a result of the existence of a fixed point for set-valued mappings in the context of 0-complete partial metric spaces. MSC:54H25, 47H10.

Discrete mathematicsInjective metric spaceApplied Mathematics010102 general mathematicsEquivalence of metricscommon fixed point01 natural sciencesConvex metric spaceIntrinsic metric010101 applied mathematicsMetric spacepoints of coincidence0-complete partial metric spaceSettore MAT/05 - Analisi Matematicaψ-contractions.Metric (mathematics)Metric mapGeometry and Topology0101 mathematicsCoincidence pointMathematicsFixed Point Theory and Applications
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A local notion of absolute continuity in IR^n

2005

We consider the notion of p, δ-absolute continuity for functions of several variables introduced in [2] and we investigate the validity of some basic properties that are shared by absolutely continuous functions in the sense of Maly. We introduce the class $δ−BV^p_loc(\Omega,IR^m)$ and we give a characterization of the functions belonging to this class.

Class (set theory)Pure mathematicsPolish groupHaar nullGeneral MathematicsMathematical analysisNull set or empty setAlgebra over a fieldAbsolute continuityCharacterization (mathematics)Modulus of continuityMathematics
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Some fixed point results for multi-valued mappings in partial metric spaces

2013

Abstract In this paper, we obtain some fixed point results for multi-valued mappings in partial metric spaces. Our results unify, generalize and complement various known comparable results from the current literature. An example is also included to illustrate the main result in the paper. MSC:46S40, 47H10, 54H25.

Discrete mathematicsPure mathematicscompleteness.Injective metric spaceApplied MathematicsIntrinsic metricConvex metric spaceMetric spacefixed pointSettore MAT/05 - Analisi Matematicamulti-valued mappingMetric (mathematics)partial Hausdorff metricMetric mapGeometry and TopologyMetric differentialCoincidence pointMathematics
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A remark on differentiable functions with partial derivatives in Lp

2004

AbstractWe consider a definition of p,δ-variation for real functions of several variables which gives information on the differentiability almost everywhere and the absolute integrability of its partial derivatives on a measurable set. This definition of p,δ-variation extends the definition of n-variation of Malý and the definition of p-variation of Bongiorno. We conclude with a result of change of variables based on coarea formula.

Change of variablesPure mathematicsPolish groupApplied MathematicsMathematical analysisNull set or empty setReal-valued functionHaar nullPartial derivativeAlmost everywhereCoarea formulaDifferentiable functionAnalysisMathematics
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Common fixed points for self mappings on compact metric spaces

2013

In this paper we obtain a result of existence of points of coincidence and of common fixed points for two self mappings on compact metric spaces satisfying a contractive condition of Suzuki type. We also present some examples to illustrate our results. Moreover, using the scalarization method of Du, we deduce a result of common fixed point in compact cone metric spaces.

Pure mathematicsApplied MathematicsInjective metric spaceFixed-point propertyTopologyIntrinsic metricConvex metric spaceComputational MathematicsUniform continuityMetric spaceRelatively compact subspaceSettore MAT/05 - Analisi MatematicaCompact metric spaces Common fixed points Suzuki fixed point theorem Scalarization Cone metric spacesMetric mapMathematicsApplied Mathematics and Computation
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Common fixed points in generalized metric spaces

2012

Abstract We establish some common fixed point theorems for mappings satisfying a ( ψ , φ ) -weakly contractive condition in generalized metric spaces. Presented theorems extend and generalize many existing results in the literature.

Discrete mathematicsComputational MathematicsMetric spaceFixed-point iterationSettore MAT/05 - Analisi MatematicaApplied MathematicsGeneralized metric weakly contractive condition contraction of integral type fixed point common fixed points.Common fixed pointProduct metricFixed pointIntrinsic metricMathematicsConvex metric space
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Common fixed points for locally lipschitz mappings

2007

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Matematica

2006

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A remark on absolutely continuous functions in IR^n

2006

We introduce the notion of α, λ-absolute continuity for functions of several variables and we compare it with the Hencl’s definition. We obtain that each α,λ-absolutely continuous function is n, λ-absolutely continuous in the sense of Hencl and hence is continuous, differentiable almost everywhere and satisfies change of variables results based on a coarea formula and an area formula.

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Fixed points for weak $\varphi$-contractions on partial metric spaces

2011

In this paper, following [W.A. Kirk, P.S. Srinivasan, P. Veeramani, Fixed points for mappings satisfying cyclical contractive conditions, Fixed Point Theory, 4 (2003) 79-89], we give a fixed point result for cyclic weak $\varphi$-contractions on partial metric space. A Maia type fixed point theorem for cyclic weak $\varphi$-contractions is also given.

Settore MAT/05 - Analisi MatematicaFixed points Partial metric space Weak cyclic $\varphi$-contractions.
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