Results 1 to 10 of about 14,437 (302)
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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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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Existence of local fractional integral equation via a measure of non-compactness with monotone property on Banach spaces [PDF]
Advances in Difference Equations, 2020 In this paper, we discuss fixed point theorems for a new χ-set contraction condition in partially ordered Banach spaces, whose positive cone K $\mathbb{K}$ is normal, and then proceed to prove some coupled fixed point theorems in partially ordered Banach
Hemant Kumar Nashine +3 more
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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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On measure of non-compactness in convex metric spaces [PDF]
Filomat, 2005 In this paper new results concerning the measure of non-compactness in convex metric spaces are presented.
Ljiljana Gajić
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Measures of non-compactness of operators on Banach lattices [PDF]
Positivity, 2002 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).
Vladimir G. Troitsky
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On Measures of Non-Compactness in Regular Spaces
Zeitschrift für Analysis und ihre Anwendungen, 1996 Previous results on non-compactness obtained in [11–13] are extended to regular spaces of measurable functions, and new criteria for the \mu -compactness of sets and operators are proved.
Nina A. Yerzakova
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On some measures of non-compactness associated to Banach operator ideals [PDF]
Journal of Approximation Theory, 2022 The first named author was supported by the Ministerio de Economía, Industria y Competitividad and FEDER under project MTM2017-84058-P. The second author was supported by the National Science Centre, Poland , Project no. 2019/33/B/ST1/00165.
Antonio Manzano, Mieczysław Mastyło
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Non-compact spaces of invariant measures [PDF]
We study a compactification of the space of invariant probability measures for a transitive countable Markov shift. We prove that it is affine homeomorphic to the Poulsen simplex. Furthermore, we establish that, depending on a combinatorial property of the shift space, the compactification contains either a single new ergodic measure or a dense set of ...
Godofredo Iommi, Aníbal Velozo
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Fixed point theorem via measure of non-compactness for a new kind of contractions
Vestnik St. Petersburg University, Mathematics, 2023 In this paper, we will use the notion of α-admissible mappings in Banach spaces, to introduce the concept of Tβ-contractive mappings and establish a fixed point theorem for this type of contractions. Our theorems generalize and improve many results in the literature.
Youssef Touail +2 more
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