Yazar "Altun, Ishak" için listeleme
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Fixed Point Theorems on Complete Quasi Metric Spaces Via C-class and A-Class Functions
Yalcin, M. Tugba; Simsek, Hakan; Altun, Ishak (UNIV MARAGHEH, 2020)In this paper, we present some fixed point theorems for single valued mappings on K-complete, M-complete and Symth complete quasi metric spaces. Here, for contractive condition, we consider some altering distance functions ... -
Fixed points of F-contractive type fuzzy mappings
Minak, Gulhan; Altun, Ishak; Olgun, Murat (Ios Press, 2017)In this paper, taking into account the recent contractive technique, which was introduced by Wardowski [18], we present a fixed point theorem for F-contractive type fuzzy mappings over a complete metric space. -
Fixed points of multivalued nonlinear F-contractions on complete metric spaces
Altun, Ishak; Minak, Gulhan; Olgun, Murat (Inst Mathematics & Informatics, 2016)We introduce a new concept for multivalued maps, also called multivalued nonlinear F-contraction, and give a fixed point result. Our result is a proper generalization of some recent fixed point theorems including the famous ... -
Fixed points of ordered F-contractions
Durmaz, Gonca; Minak, Gulhan; Altun, Ishak (Hacettepe Univ, Fac Sci, 2016)In his recent paper, Wardowski [16] introduced the concept of F-contraction, which is a proper generalization of ordinary contraction on a complete metric space. Then, some generalizations of F-contractions including ... -
Generalized contractions on partial metric spaces
Altun, Ishak; Sola, Ferhan; Simsek, Hakan (Elsevier Science Bv, 2010)In the present paper, we give some fixed point theorems for generalized contractive type mappings on partial metric space. Also, a homotopy result is given. (C) 2010 Elsevier B.V. All rights reserved. -
Generalized Theta-contractive fuzzy mappings
Ahmad, Jamshaid; Al-Mazrooei, Abdullah Eqal; Altun, Ishak (Ios Press, 2018)The aim of this paper is to obtain some common alpha-fuzzy fixed point theorems under generalized Theta-contraction in the setting of complete metric space. In this way, we generalize various results of literature including ... -
Lyapunov-type inequalities for a fractional p-Laplacian equation
Al Arifi, Nassir; Altun, Ishak; Jleli, Mohamed; Lashin, Aref; Samet, Bessem (Springeropen, 2016)In this paper, we present new Lyapunov-type inequalities for a fractional boundary value problem that models a turbulent flow in a porous medium. The obtained inequalities are used to obtain a lower bound for the eigenvalues ... -
Multivalued Almost F-contractions on Complete Metric Spaces
Altun, Ishak; Durmaz, Gonca; Minak, Gulhan; Romaguera, Salvador (Univ Nis, Fac Sci Math, 2016)In the present paper, considering a new concept of multivalued almost F-contraction, we give a general class of multivalued weakly Picard operators on complete metric spaces. Also, we give some illustrative examples showing ... -
Multivalued F-Contractions On Complete Metric Spaces
Altun, Ishak; Minak, Gulhan; Dag, Hacer (Yokohama Publ, 2015)In the present paper, we introduce the concept of multivalued F-contraction mappings and give some fixed point results, which generalize some multivalued fixed point theorems including Nadler's. Also, we give an illustrating ... -
Multivalued F-contractive mappings with a graph and some fixed point results
Acar, Ozlem; Altun, Ishak (Kossuth Lajos Tudomanyegyetem, 2016)The main goal of this paper is to introduce a new type contraction, that is, multivalued F-G-contraction, on a metric space with a graph. In terms of this new contraction, we establish some fixed point results. At the end, ... -
Multivalued Pseudo-Picard Operators and Fixed Point Results
Minak, Gulhan; Acar, Ozlem; Altun, Ishak (Hindawi Ltd, 2013)We introduce the concept of multivalued pseudo-Picard (MPP) operator on ametric space. This concept is weaker than multivalued weakly Picard (MWP) operator, which is given by M. Berinde and V. Berinde (2007). Then, we give ... -
A New Approach for the Approximations of Solutions to a Common Fixed Point Problem in Metric Fixed Point Theory
Altun, Ishak; Al Arifi, Nassir; Jleli, Mohamed; Lashin, Aref; Samet, Bessem (Hindawi Publishing Corp, 2016)We provide sufficient conditions for the existence of a unique common fixed point for a pair of mappings T,S : X > X where X is a nonempty set endowed with a certain metric. Moreover, a numerical algorithm is presented in ... -
A new approach to fixed point theorems for multivalued contractive maps
Minak, Gulhan; Olgun, Murat; Altun, Ishak (North Univ Baia Mare, 2015)In the present paper, considering the Wardowski's technique we give many fixed point results for multivalued maps on complete metric space without using the Hausdorff metric. Our results are real generalization of some ... -
A New Approach To Mizoguchi-Takahashi Type Fixed Point Theorems
Olgun, Murat; Minak, Gulhan; Altun, Ishak (Yokohama Publ, 2016)In the present paper, we give a generalization of Mizoguchi-Takahashi's fixed point theorem, which is a partial solution of Reich's original problem concerning multivalued mappings on complete metric spaces. -
A new approach to the Assad-Kirk fixed point theorem
Altun, Ishak; Olgun, Murat; Minak, Gulhan (Springer Basel Ag, 2016)In the present paper, considering the Wardowski's technique, we give a new approach to the Assad-Kirk fixed point theorem on metrically convex metric spaces. We also provide a nontrivial example showing that our result is ... -
A new concept of (alpha, F-d)-contraction on quasi metric space
Altun, Ishak; Al Arifi, Nasir; Jleli, Mohamed; Lashin, Aref; Samet, Bessem (Int Scientific Research Publications, 2016)In the present paper, we introduce a new concept of (alpha, F-d)-contraction on quasi metric space. Then we provide some new fixed point theorems for such type mappings on left K, left M and left Smyth-complete quasi metric ... -
New fixed point results for maps satisfying implicit relations on ordered metric spaces and application
Nashine, Hemant Kumar; Altun, Ishak (Elsevier Science Inc, 2014)We give some fixed point results for one and two mappings satisfying an implicit relation involving control function on ordered complete metric spaces. We furnish suitable examples to demonstrate the validity of the ... -
A New Perspective For Multivalued Weakly Picard Operators
Durmaz, Gonca; Altun, Ishak (Publications L Institut Mathematique Matematicki, 2017)This research contains some recent developments about multivalued weakly Picard operators on complete metric spaces. In addition, taking into account both multivalued theta-contraction and almost contraction on complete ... -
Nonlinear proximinal multivalued contractions on quasi-metric spaces
Altun, Ishak; Dag, Hacer (Springer Basel Ag, 2017)In this paper, taking into account the concept of proximinal set, we obtain some new fixed point results for nonlinear proximinal multivalued contractions on some kind of complete quasi-metric spaces. Also, we present some ... -
On A Broad Category Of Multivalued Weakly Picard Operators
Hancer, Hatice Aslan; Minak, Gulhan; Altun, Ishak (House Book Science-Casa Cartii Stiinta, 2017)In the present paper, considering a recent technique which is used by Jleli and Samet [10] for fixed points of single-valued maps, we introduce a new concept of multivalued theta-contractions on metric spaces and prove ...