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      • Open Access Article

        1 - Solving infinite system of nonlinear integral equations by using ‎F-‎generalized Meir-Keeler condensing operators, measure of noncompactness and modified homotopy perturbation.
        mohsen rabbani Reza Arab
        In this article to prove existence of solution of infinite system of nonlinear integral equations, we consider the space of solution containing all convergence sequences with a finite limit, as with a suitable norm is a Banach space. By creating a generalization of Meir More
        In this article to prove existence of solution of infinite system of nonlinear integral equations, we consider the space of solution containing all convergence sequences with a finite limit, as with a suitable norm is a Banach space. By creating a generalization of Meir-Keeler condensing operators which is named as F-generalized Meir-Keeler condensing operators and measure of noncompactness, we prove some fixed point theorems. With the help of the above process we try to generalize some theorems which were proved by other authors such as [3, 19] about existence of solution by fixed point theorems. Then for validity and application‎ of our proposed theorems, we prove existence of solution for infinite system of nonlinear integral equations. Finally for ability and more attractiveness of this research, we construct an iteration algorithm by modified homotopy perturbation and Adomian decomposition method to obtain approximation of solution of the infinite system of nonlinear integral equations. Manuscript profile
      • Open Access Article

        2 - A new characterization for Meir-Keeler condensing operators and its applications
        H. Khandani F. Khojasteh
        Darbo's fixed point theorem and its generalizations play a crucial role in the existence of solutions in integral equations. Meir-Keeler condensing operators is a generalization of Darbo's fixed point theorem and most of other generalizations are a special case of this More
        Darbo's fixed point theorem and its generalizations play a crucial role in the existence of solutions in integral equations. Meir-Keeler condensing operators is a generalization of Darbo's fixed point theorem and most of other generalizations are a special case of this result. In recent years, some authors applied these generalizations to solve several special integral equations and some of them presented a characterization for Meir-Keeler condensing operators, which needs L-functions. But, finding an appropriate L-function needs more struggle. In this paper, we give a characterization for Meir-Keeler condensing operators via measure of non-compactness. Current characterization presents a criterion by which we can show that if a given generalization of Darbo's fixed point theorem is Meer-Keeler condensing or not. Ultimately, we give several corollaries and point out several generalizations of Darbo's fixed point theorem and show that all of them are Meir-Keeler condensing operator or a special case of this result. Manuscript profile
      • Open Access Article

        3 - Some generalizations of Darbo's theorem for solving a systems of functional-integral equations via measure of noncompactness
        Jamal Rezaei Roshan
        In this paper, using the concept of measure of noncompactness, which is a very useful and powerful tools in nonlinear functional analysis, metric fixed point theory and integral equations, we introduce a new contraction on a Banach space. For this purpose by using of a More
        In this paper, using the concept of measure of noncompactness, which is a very useful and powerful tools in nonlinear functional analysis, metric fixed point theory and integral equations, we introduce a new contraction on a Banach space. For this purpose by using of a measure of noncompactness on a finite product space, we obtain some generalizations of Darbo’s fixed-point theorem. Then, with the obtained results, we present some theorems on the existence of coupled fixed point for a class of operators in a Banach space. Our results generalize and extend a lot of comparable results in the literature. Also as an application, we study the existence of solution for a class of the system of nonlinear functional integral equations, which the functions and operators in the related integral operators, satisfies in a particular contraction. Finllay a concrete example is also included, which demonstrates the applicability of the obtaind results. Manuscript profile