Results 1 to 10 of about 175 (113)
Remarks on a measure of weak noncompactness in the Lebesgue space [PDF]
Bulletin of the Australian Mathematical Society, 1995 Using the concept of equi-integrability we introduce a measure of weak noncompactness in the Lebesgue space L1(0, l). We show that this measure is equal to the classical De Blasi measure of weak noncompactness.
Banaś, Józef, Sadarangani, Kishin
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Weak solutions for a coupled system of Pettis-Hadamard fractional differential equations
Advances in Difference Equations, 2017 In this paper, by applying the technique of measure of weak noncompactness and Mönch’s fixed point theorem, we investigate the existence of weak solutions under the Pettis integrability assumption for a coupled system of Hadamard fractional differential ...
Saïda Abbas +3 more
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Solvability of functional quadratic integral equations with perturbation [PDF]
Opuscula Mathematica, 2013 We study the existence of solutions of the functional quadratic integral equation with a perturbation term in the space of Lebesgue integrable functions on an unbounded interval by using the Krasnoselskii fixed point theory and the measure of weak ...
Mohamed M. A. Metwali
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Implicit coupled Hilfer–Hadamard fractional differential systems under weak topologies
Advances in Difference Equations, 2018 In this article, we present some existence of weak solutions for a coupled system of implicit fractional differential equations of Hilfer–Hadamard type. Our approach is based on Mönch’s fixed point theorem associated with the technique of measure of weak
Saïd Abbas +3 more
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Leray–Schauder Fixed Point Theorems for Block Operator Matrix with an Application
Journal of Mathematics, 2021 In this paper, we establish some new variants of Leray–Schauder-type fixed point theorems for a 2×2 block operator matrix defined on nonempty, closed, and convex subsets Ω of Banach spaces. Note here that Ω need not be bounded.
Mohamed Amine Farid +2 more
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Filomat, 2022 In this paper, we show that an unbounded weakly S0-demicompact linear operator T, introduced in [18], acting on a Banach space, can be characterized by some measures of weak noncompactness. Moreover, our results are illustrated to discuss the relationship with Fredholm and upper semi-Fredholm operators as well as the stability of the ...
Aref Jeribi, Bilel Krichen, Makrem Salhi
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Measure of weak noncompactness and real interpolation of operators [PDF]
Bulletin of the Australian Mathematical Society, 2000 A new measure of weak noncompactness is introduced. A logarithmic convexity-type result on the behaviour of this measure applied to bounded linear operators under real interpolation is proved. In particular, it gives a new proof of the theorem showing that if at least one of the operators T: Ai → Bi, i = 0, 1 is weakly compact, then so is T : Aθ,p → Bθ,
Kryczka, Andrzej +2 more
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Boundary Value Problems, 2023 In this paper, we present the definitions of fractional integrals and fractional derivatives of a Pettis integrable function with respect to another function.
Hussein A. H. Salem +2 more
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Coupled Pettis Hadamard fractional differential systems with retardation and anticipation [PDF]
Surveys in Mathematics and its Applications, 2021 In this article, we study some existence results concerning the weak solutions for some coupled systems of Hadamard fractional differential equations with the mixed arguments of anticipations and retardation.
Sa\id Abbas +3 more
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Radon–Nikodým indexes and measures of weak noncompactness
Journal of Functional Analysis, 2014 The authors introduce and study certain indices related to the Radon-Nikodým property in Banach spaces. Interesting quantitative versions of classic results in RNP are proved. Let \(E\) be a Banach space and \((\Omega,\Sigma,\mu)\) a complete probability space.
Cascales, B., Pérez, A., Raja, M.
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