Search Results

Now showing 1 - 10 of 17
  • Article
    Citation - WoS: 63
    Citation - Scopus: 75
    Α-Ψ Contraction Type Mappings and Some Related Fixed Point Results
    (Univ Nis, Fac Sci Math, 2014) Karapinar, Erdal
    In this paper, we consider a generalization of alpha-psi-Geraghty contractions and investigate the existence and uniqueness of fixed point for the mapping satisfying this condition. We illustrate an example and an application to support our results. In particular, we extend, improve and generalize some earlier results in the literature on this topic.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 5
    Mild Solutions for Conformable Fractional Order Functional Evolution Equations Via Meir-Keeler Type Fixed Point Theorem
    (Univ Nis, Fac Sci Math, 2025) Berrighi, Fatma; Medjadj, Imene; Karapinar, Erdal
    In this study, we delve into the realm of mild solutions for conformable fractional order functional evolution equations, focusing on cases where the fractional order is strictly greater than 1 and less than 2 within a separable Banach space. We demonstrate the existence, uniqueness, attractivity, and controllability of these solutions under local conditions. Our approach involves leveraging a contribution of Meir-Keeler's fixed point theorem alongside the principle of measures of noncompactness. To demonstrate the practical ramifications of our theoretical finds, we provide a specific example that underscores the relevance and applications of the established results.
  • Article
    Citation - WoS: 23
    Citation - Scopus: 31
    A Discussion on "α-Ψ Contraction Type Mappings "
    (Univ Nis, Fac Sci Math, 2014) Karapinar, Erdal
    In this paper we discuss the subadditivity property of some auxiliary functions which have been used to generalize the contractive conditions on maps. Our results show that this property is not required in many cases and therefore, can be removed. We emphasize that in several papers (see e.g.[1]-[11]) dealing with such contraction mappings, the hypotheses of the main theorems can be restated in the light of our results.
  • Article
    Citation - WoS: 88
    Citation - Scopus: 97
    Modified f-contractions Via α-admissible Mappings and Application To Integral Equations
    (Univ Nis, Fac Sci Math, 2017) Aydi, Hassen; Karapinar, Erdal; Yazidi, Habib
    In this paper, we introduce the concept of a modified F-contraction via alpha-admissible mappings and propose some theorems that guarantee the existence and uniqueness of fixed point for such mappings in the frame of complete metric spaces. We also provide some illustrative examples. Moreover, we consider an application solving an integral equation.
  • Article
    Citation - WoS: 18
    Citation - Scopus: 24
    Generalized Α -Meir Contraction Mappings on Branciari B-Metric Spaces
    (Univ Nis, Fac Sci Math, 2017) Gulyaz, Selma; Karapinar, Erdal; Erhan, Inci M.
    In this paper, alpha-Meir-Keeler and generalized alpha-Meir-Keeler contractions on Branciari b-metric spaces are introduced. Existence and uniqueness of fixed points of such contractions are discussed and related theorems are proved. Various consequences of the main results are also presented.
  • Article
    Citation - WoS: 19
    Citation - Scopus: 17
    Further Discussion on Modified Multivalued Α*-ψ-contractive Type Mapping
    (Univ Nis, Fac Sci Math, 2015) Ali, Muhammad Usman; Kamran, Tayyab; Karapinar, Erdal
    In this paper, we investigate the existence of a fixed point for modified multivalued alpha(*)-psi-contractive type mapping in the context of complete metric space. We also construct some examples to illustrate the main result. Our results extend, improve and generalize the results on the topic in the literature.
  • Article
    Citation - WoS: 21
    Citation - Scopus: 23
    On (α, Ψ)-k-contractions in the Extended b-metric Space
    (Univ Nis, Fac Sci Math, 2018) Alqahtani, Badr; Karapinar, Erdal; Ozturk, Ali
    In this paper, we introduce a notion of (alpha, psi)-K-contraction in the setting of extended b-metric spaces and investigate the existence of a fixed point. The presented results generalize and unify a number of well-known fixed point theorem mainly in two distinct aspects; in the sense of the contraction conditions and in the frame of abstract spaces.
  • Article
    Citation - WoS: 43
    A Common Fixed Point Theorem for Cyclic Operators on Partial Metric Spaces
    (Univ Nis, Fac Sci Math, 2012) Karapinar, Erdal; Karapınar, Erdal; Shobkolaei, Nabi; Sedghi, Shaban; Vaezpour, S. Mansour; Karapınar, Erdal; Mathematics; Mathematics
    In this paper, we prove a common fixed point theorem for two self-mappings satisfying certain conditions over the class of partial metric spaces. In particular, the main theorem of this manuscript extends some well-known fixed point theorems in the literature on this topic.
  • Article
    Citation - WoS: 25
    Citation - Scopus: 32
    Fixed Point Theorems in Complete Modular Metric Spaces and an Application To Anti-Periodic Boundary Value Problems
    (Univ Nis, Fac Sci Math, 2017) Aksoy, Umit; Karapinar, Erdal; Erhan, Inci M.
    In this paper existence and uniqueness of fixed points for a general class of contractive and nonexpansive mappings on modular metric spaces is discussed. As an application of the theoretical results, the existence of a solution of anti-periodic boundary value problems for nonlinear first order differential equations of Caratheodory's type is considered in the framework of modular metric spaces.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 9
    On Interpolative Metric Spaces
    (Univ Nis, Fac Sci Math, 2024) Karapinar, Erdal
    The purpose of this article is to expand the "open discussion" on the definition and necessity of the interpolation metric space and keep it on the agenda of researchers in nonlinear functional analysis. The secondary aim of this article is to indicate that the outcomes of this "open discussion" have the potential to stop the recent recession in the metric fixed point theory.