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arXiv · 2210.13176

Regular measures of noncompactness and Ascoli-Arzel\` a type compactness criteria in spaces of vector-valued function

Diana Caponetti·Alessandro Trombetta·Giulio Trombetta
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Abstract

In this paper we estimate the Kuratowski and the Hausdorff measures of noncompactness of bounded subsets of spaces of vector-valued bounded functions and of vector-valued bounded differentiable functions. To this end, we use a quantitative characteristic modeled on a new equiconti\-nuity-type concept and classical quantitative characteristics related to pointwise relative compactness. We obtain new regular measures of noncompactness in the spaces taken into consideration. The established inequalities reduce to precise formulas in some classes of subsets. We derive Ascoli-Arzel\` a type compactness criteria.

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Diana Caponetti, Alessandro Trombetta, Giulio Trombetta. 2022-10-24. Regular measures of noncompactness and Ascoli-Arzel\` a type compactness criteria in spaces of vector-valued function. https://arxiv.org/abs/2210.13176

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