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Erdal Karapınar - One of the best experts on this subject based on the ideXlab platform.
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Quadruple fixed point theorems for nonlinear contractions on partial metric spaces
Applied General Topology, 2014Co-Authors: Erdal Karapınar, Kenan TaşAbstract:The notion of coupled fixed point was introduced by Guo and Laksmikantham [12]. Later Gnana Bhaskar and Lakshmikantham in [11] investigated the coupled fixed points in the setting of partially ordered set by defining the notion of mixed monotone property. Very recently, the concept of tripled fixed point was introduced by Berinde and Borcut [7]. Following this trend, Karapinar[19] defined the quadruple fixed point. In this manuscript, quadruple fixed point is discussed and some new fixed point theorems are obtained on partial metric spaces.
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Multidimensional Fixed-Point Theorems in Partially Ordered Complete Partial Metric Spaces under ()-Contractivity Conditions
Abstract and Applied Analysis, 2013Co-Authors: A. Roldán, Juan Martínez-moreno, C. Roldán, Erdal KarapınarAbstract:We study the existence and uniqueness of coincidence point for nonlinear mappings of any number of arguments under a weak ( )-contractivity condition in partial metric spaces. The results we obtain generalize, extend, and unify several classical and very recent related results in the literature in metric spaces (see Aydi et al. (2011), Berinde and Borcut (2011), Gnana Bhaskar and Lakshmikantham (2006), Berzig and Samet (2012), Borcut and Berinde (2012), Choudhury et al. (2011), Karapinar and Luong (2012), Lakshmikantham and Ciric (2009), Luong and Thuan (2011), and Roldan et al. (2012)) and in partial metric spaces (see Shatanawi et al. (2012)).
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Quadruple fixed point theorems for nonlinear contractions
Computers & Mathematics with Applications, 2012Co-Authors: Erdal Karapınar, Nguyen Van LuongAbstract:The notion of coupled fixed point is introduced by Gnana-Bhaskar and Lakshmikantham. Very recently, the concept of tripled fixed point was introduced by Berinde and Borcut. In this manuscript, a quadruple fixed point is considered and some new related fixed point theorems are obtained. We also give some examples to illustrate our results.
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Quadruple Fixed Point Theorems for Weak ϕ-Contractions
ISRN Mathematical Analysis, 2011Co-Authors: Erdal KarapınarAbstract:The notion of coupled fixed point is introduced in by Gnana Bhaskar and Lakshmikantham (2006). Very recently, the concept of tripled fixed point is introduced by Berinde and Borcut (2011). In this paper, quadruple fixed point is introduced, and some new fixed point theorems are obtained.
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Quartet fixed point for nonlinear contraction
arXiv: General Topology, 2011Co-Authors: Erdal KarapınarAbstract:The notion of coupled fixed point is introduced in by Bhaskar and Lakshmikantham in [2]. Very recently, the concept of tripled fixed point is introduced by Berinde and Borcut [1]. In this manuscript, by using the mixed g monotone mapping, some new quartet fixed point theorems are obtained. We also give some examples to support our results.
Stojan Radenović - One of the best experts on this subject based on the ideXlab platform.
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Coupled Fixed Point Theorems for Contractive Mappings Involving New Function Classes and Applications
Filomat, 2017Co-Authors: H Arslan Ansari, Hüseyin Işık, Stojan RadenovićAbstract:The aim of this paper is to extend the results of Bhaskar and Lakshmikantham and some other authors and to prove some new coupled fixed point theorems for contractive mappings involving new function classes in complete metric space endowed with a partial order. Our theorems can be used to investigate a large class of nonlinear problems. As an application, we discuss the existence and uniqueness for a solution of a nonlinear integral equation.
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Bhaskar-Lakshmikantham type results for monotone mappings in partially ordered metric spaces
International Journal of Nonlinear Analysis and Applications, 2014Co-Authors: Stojan RadenovićAbstract:In this paper, coupled xed point results of Bhaskar-Lakshmikantham type [T. Gnana Bhaskar, V.Lakshmikantham, Fixed point theorems in partially ordered metric spaces and applications, NonlinearAnalysis 65 (2006) 1379-1393] are extend, generalized, unify and improved by using monotonemappings instead mappings with mixed monotone property. Also, an example is given to supportthese improvements.
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Some Remarks on Multidimensional Fixed Point Theorems in Partially Ordered Metric Spaces.
Journal of Advances in Mathematics, 2014Co-Authors: Sumitra Dalal, Ibtisam Masmali, Liaqat Ali Khan, Stojan RadenovićAbstract:In this paper , we show that multidimensional ( coupled, tripled, quadrupled, n-tupled) theorems can be reduced to unidimensional fixed point theorems. . Our results generalize, extend and improve the coupled fixed point results of Bhaskar and Lakshmikantham, Nonlinear Analysis: Theory, Methods and Applications, vol.65, no.7, 2006, pp. 1379-1393, V. Lakshmikantham and L. Ciric, Nonlinear Analysis, Theory, Method and Applications, vol. 70, no12, 2009, pp. 4341-4349, tripled fixed point theorems by Berinde and Borcut, Nonlinear Analysis, Volume 74, Issue 15, October 2011, Pages 4889-4897, Quadruple fixed point theorems by E. Karapinar and V. Berinde, Banach Journal of Mathematical Analysis, vol. 6, no. 1, pp. 74–89, 2012 and multidimensional fixed point results by Muzeyyen Erturk and Vatan Karakaya, Journal of Inequalities and Applications 2013, 2013:196, pp. 1-19, M. Imdad, A. H. Soliman, B. S. Choudhary and P. Das, Journal of Operators, Volume 2013, Article ID 532867, pp. 1-8 and M. Paknazar, M. E. Gordji, M. D. L. Sen and S. M. Vaezpour, Fixed Point Theory and Applications 2013, 2013:11 etc.
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Coupled fixed point theorems for monotone mappings in partially ordered metric spaces
Kragujevac Journal of Mathematics, 2014Co-Authors: Stojan RadenovićAbstract:In this paper, by reducing of coincidence and coupled fixed point results in ordered metric spaces to the respective results for mappings with one variable, some recent results established by T. G. Bhaskar and V. Lakshmikantham [T. G. Bhaskar, V. Lakshmikantham, Fixed point theorems in partially ordered metric spaces and applications, Nonlinear Analysis 65 (2006) 1379-1393], V. Lakshmikantham and L. Ciric [V. Lakshmikantham, L. Ciric, Coupled fixed point theorems for nonlinear contractions in partially ordered metric spaces, Nonlinear Analysis 70 (2009) 4341-4349] are extended, generalized, unified and improved by using mappings with monotonicity instead of with mixed monotone property. Moreover, two examples are given to support these improvements.
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Coupled coincidence point theorems for generalized nonlinear contraction in partially ordered metric spaces
Fixed Point Theory and Applications, 2012Co-Authors: Hui-sheng Ding, Stojan RadenovićAbstract:This paper is concerned with mixed g-monotone mappings in partially ordered metric spaces. We establish several coupled coincidence and coupled common fixed point theorems, which generalize and complement some known results. Especially, our main results complement some recent results due to Lakshmikantham and Ciric. Two examples are given to illustrate the usability of our results.
Isabel Marrero - One of the best experts on this subject based on the ideXlab platform.
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Weak compactness and the Eisenfeld-Lakshmikantham measure of nonconvexity
Fixed Point Theory and Applications, 2012Co-Authors: Isabel MarreroAbstract:In this article, weakly compact subsets of real Banach spaces are characterized in terms of the Cantor property for the Eisenfeld-Lakshmikantham measure of nonconvexity. This characterization is applied to prove the existence of fixed points for condensing maps, nonexpansive maps, and isometries without convexity requirements on their domain. Mathematics Subject Classification 2010: Primary 47H10; Secondary 46B20, 47H08, 47H09.
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A note on reflexivity and nonconvexity
Nonlinear Analysis: Theory Methods & Applications, 2011Co-Authors: Isabel MarreroAbstract:Abstract In this short note we prove that a Banach space X is reflexive if, and only if, the Eisenfeld–Lakshmikantham measure of nonconvexity in X satisfies the Cantor property. Using this characterization, some results in best approximation and fixed point theory for reflexive Banach spaces are generalized by removing convexity requirements.
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Measures of Noncircularity and Fixed Points of Contractive Multifunctions
Fixed Point Theory and Applications, 2010Co-Authors: Isabel MarreroAbstract:In analogy to the Eisenfeld-Lakshmikantham measure of nonconvexity and the Hausdorff measure of noncompactness, we introduce two mutually equivalent measures of noncircularity for Banach spaces satisfying a Cantor type property, and apply them to establish a fixed point theorem of Darbo type for multifunctions. Namely, we prove that every multifunction with closed values, defined on a closed set and contractive with respect to any one of these measures, has the origin as a fixed point.
Madjid Eshaghi Gordji - One of the best experts on this subject based on the ideXlab platform.
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N-fixed point theorems for nonlinear contractions in partially ordered metric spaces
Fixed Point Theory and Applications, 2013Co-Authors: Mohadeseh Paknazar, Madjid Eshaghi Gordji, Manuel De La Sen, S. M. VaezpourAbstract:In present paper we introduce the concept of a new g-monotone mapping and define the notions of n-fixed point and n-coincidence point and prove some related theorems for nonlinear contractive mappings in partially ordered complete metric spaces. Our results are generalization of the main results of Lakshmikantham and Ciric (Nonlinear Anal. 70:4341-4349, 2009) and include several recent developments. Moreover, we give an example to support our results.
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Coupled common fixed point theorems for mixed weakly monotone mappings in partially ordered metric spaces
Fixed Point Theory and Applications, 2012Co-Authors: Madjid Eshaghi Gordji, Yeol Je Cho, Esmat Akbartabar, Maryam RamezaniAbstract:In this paper, we introduce the concept of a mixed weakly monotone pair of mappings and prove some coupled common fixed point theorems for a contractive-type mappings with the mixed weakly monotone property in partially ordered metric spaces. Our results are generalizations of the main results of Bhaskar and Lakshmikantham and Kadelburg et al.
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Coupled fixed point theorems for contractions in intuitionistic fuzzy normed spaces
Mathematical and Computer Modelling, 2011Co-Authors: Madjid Eshaghi Gordji, Hamid Baghani, Yeol Je ChoAbstract:Abstract Following the definition of coupled fixed point [T. G. Bhaskar, V. Lakshmikantham, Fixed point theorems in partially ordered metric spaces and applications, Nonlinear Anal. 65 (2006) 1379–1393], we prove a coupled fixed point theorem for contractive mappings in partially complete intuitionistic fuzzy normed spaces.
D. D. Bainov - One of the best experts on this subject based on the ideXlab platform.
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Monotone-Iterative Techniques of V. Lakshmikantham for a Boundary Value Problem for Systems of Impulsive Differential-Difference Equations
Journal of Mathematical Analysis and Applications, 1996Co-Authors: Snezhana Hristova, D. D. BainovAbstract:By means of the monotone-iterative techniques of V. Lakshmikantham a couple of minimal and maximal quasisolutions of a two-point boundary value problem for a system of impulsive differential-difference equations are constructed.
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Monotone-Iterative Techniques of Lakshmikantham for a Boundary Value Problem for Systems of Differential Equations with Maxima
Journal of Mathematical Analysis and Applications, 1995Co-Authors: D. D. Bainov, Snezhana HristovaAbstract:Abstract The monotone-iterative techniques of Lakshmikantham are applied to approximately finding a couple of extremal quasi-solutions of a two-point boundary value problem for systems of differential equations with maxima.
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Application of Lakshmikantham's monotone-iterative technique to the solution of the initial value problem for impulsiveintegro-differential equations
Journal of Applied Mathematics and Stochastic Analysis, 1993Co-Authors: D. D. Bainov, Snezhana HristovaAbstract:In the present paper, a technique of V. Lakshmikantham is applied to approximate finding of extremal quasisolutions of an initial value problem for a system of impulsive integro-differential equations of Volterra type.
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Monotone-iterative techniques of V. Lakshmikantham for a boundary value problem for systems of impulsive differential equations with «Supremum»
Journal of Mathematical Analysis and Applications, 1993Co-Authors: Snezhana Hristova, D. D. BainovAbstract:Abstract By means of the monotone-iterative techniques of V. Lakshmikantham, which combine the ideas of the method of upper and lower solutions and a suitably chosen monotone method, a couple of extremal quasisolutions of a two-point boundary value problem for a system of impulsive differential equations with "supremum" is constructed.