Results 11 to 20 of about 123,114 (281)
On a measure of non-compactness for singular integrals [PDF]
Journal of Function Spaces and Applications, 2003 It is proved that there exists no weight pair (v, w) for which a singular integral operator is compact from the weighted Lebesgue space Lwp(Rn) to Lvp(Rn). Moreover, a measure of non-compatness for this operator is estimated from below.
Alexander Meskhi
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On the measure of non-compactness of maximal operators
Journal of Function Spaces and Applications, 2004 In one of the previous articles of the author it was proved that if B is a convex quasi-density measurable basis and E is a symmetric space on Rn with respect to the Lebesgue measure, then there do not exist non-orthogonal weights w and v for which the ...
Georgi G. Oniani
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Interpolation of the Measure of Non Compactness between Quasi-Banach Spaces [PDF]
Revista Matemática Complutense, 2006 We study the behavior of the ball measure of non-compactness under several interpolation methods. First we deal with methods that interpolate couples of spaces, and then we proceed to extend the results to methods that interpolate finite families of ...
Fernández Martínez, Pedro
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Fixed point results for condensing operators via measure of non-compactness
Vestnik of Saint Petersburg University. Mathematics. Mechanics. Astronomy, 2022 In this paper, we prove some fixed point theorems for condensing operators in the setting of Banach spaces via measure of non-compactness, without using regularity. Our results improve and generalize many known results in the literature.
Touail, Youssef +2 more
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Measures of Non-compactness of Operators on Banach Lattices [PDF]
Positivity, 2004 Andreu et al [2] and Sadovskii [11] used representation spaces to study measures of non-compactness and spectral radii of operators on Banach lattices. In this paper, we develop representation spaces based on the nonstandard hull construction (which is equivalent to the ultrapower construction).
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MEASURE OF NON-COMPACTNESS IN THE LORENTZ SPACES
Научный вестник МГТУ ГА, 2016 Geometric characteristics of regular spaces are determined. Examples of regular spaces are the Lebesgue and Lorentz spaces, in particular. For the Lorentz spaces an inequality for arbitrary subsets, connecting the measures of noncompactness and are ...
N. A. Erzakova
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Measure of non-compactness and limiting interpolation with slowly varying functions
Banach Journal of Mathematical AnalysisAbstractWe give estimates for the measure of non-compactness of an operator interpolated by the limiting methods involving slowly varying functions. As applications we establish estimates for the measure of non-compactness of operators acting between Lorentz–Karamata spaces.
Fernando Cobos +2 more
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New Generalization of Darbo's Fixed Point Theorem via $alpha$-admissible Simulation Functions with Application [PDF]
Sahand Communications in Mathematical Analysis, 2020 In this paper, at first, we introduce $alpha_{mu}$-admissible, $Z_mu$-contraction and $N_{mu}$-contraction via simulation functions. We prove some new fixed point theorems for defined class of contractions via $alpha$-admissible simulation mappings ...
Hossein Monfared +2 more
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LOGARITHMIC INTERPOLATION METHODS AND MEASURE OF NON-COMPACTNESS [PDF]
The Quarterly Journal of Mathematics, 2019 Abstract We derive interpolation formulae for the measure of non-compactness of operators interpolated by logarithmic methods with $\theta = 0,1$ between quasi-Banach spaces. Applications are given to operators between Lorentz–Zygmund spaces.
Cobos Díaz, Fernando +1 more
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Fractal and Fractional, 2023 This study demonstrates the total control of a class of hybrid neutral fractional evolution equations with non-instantaneous impulses and non-local conditions.
Ahmed Salem, Kholoud N. Alharbi
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