Results 61 to 70 of about 89 (78)

Measure of weak noncompactness, some new properties in Fredholm theory, characterization of the Schechter essential spectrum and application to transport operators

Ricerche Di Matematica, 2012
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Aref Jeribi, Maher Mnif
exaly   +3 more sources

A Measure of Weak Noncompactness in $$L^1({\mathbb {R}}^N)$$ and Applications

Mediterranean Journal of Mathematics, 2022
A new measure of weak noncompactness in the Banach space \(L^1(\mathbb{R}^N)\) is proposed. It is a generalization of the Banas-Knap measure of weak noncompactness, which in turn is a generalization of the De Blasi measure of weak noncompactness. Then, the multidimensional nonlinear functional integral equation \[ u(t,x)=f(t,x,u(t,x))+ g\left( t,x ...
Bilal Boulfoul, Smail Djebali
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Stability of relative essential spectra of the transport operator in $$L^1$$-space by means of measures of noncompactness and relative weak demicompactness

Monatshefte für Mathematik, 2022
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Chelly, Slim, Jeribi, Aref, Krichen, Bilel   +2 more
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On measures of weak noncompactness

Publicationes Mathematicae Debrecen, 1994
A notion of measure of weak noncompactness is introduced which generalizes the De Blasi measure of weak noncompactness. Some properties of this generalized measure are proved. The existence of bounded weak solutions of certain differential equations is shown.
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Measures of Weak Noncompactness and Fixed Points

2017
The interaction between measures of weak noncompactness and fixed point theory is really strong and fruitful. In particular, measures of weak noncompactness play a significant role in topological fixed point problems. The purpose of this chapter is to exhibit the importance of the use of measures of weak noncompactness in topological fixed point theory
Agnieszka Chlebowicz, Mohamed-Aziz Taoudi   +1 more
openaire   +1 more source

Convexification of super weakly compact sets and measure of super weak noncompactness

Proceedings of the American Mathematical Society, 2021
In the paper, we give a quantitative version of the positive answer to the open question about the convex hull of a super weakly compact set. Measure of super weak noncompactness σ
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Measures of weak noncompactness, nonlinear leray-schauder alternatives in banach algebras satisfying condition (p) and an application

Quaestiones Mathematicae, 2015
In this paper, we establish some new nonlinear Leray-Schauder alternatives for the sum and the product of weakly sequentially continuous operators in Banach algebras satisfying certain sequential condition (P). The main condition in our results is formulated in terms of axiomatic measures of weak noncompactness.
Ali, Amro Alsheikh, Amar, Afif Ben
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Measures of weak noncompactness and fixed point theory in banach algebras satisfying condition (P)

2017
The aim of this paper is to prove some new fixed point theorems in a nonempty closed convex subset of a Banach algebra satisfying a sequential condition (P) in a weak topology setting.
Ben Amar, Afif, O’Regan, Donal
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Results on controllability of Hilfer fractional differential equations with infinite delay via measures of noncompactness

Asian Journal of Control, 2022
V Vijayakumar, Udhayakumar Ramalingam, C Ravichandran   +2 more
exaly  

Tripled Fixed Points and Existence Study to a Tripled Impulsive Fractional Differential System via Measures of Noncompactness

Mathematics, 2022
Maria Alessandra Ragusa, Sina Etemad, Mohammed M Matar   +2 more
exaly