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http://dx.doi.org/10.14317/jami.2022.669

THE OPERATORS 𝜋G OF BEST APPROXIMATIONS AND CONTINUOUS METRIC PROJECTIONS  

RHEE, HYANG JOO (Department of Mathematics, College of Natural Sciences, Duksung Women's University)
Publication Information
Journal of applied mathematics & informatics / v.40, no.3_4, 2022 , pp. 669-674 More about this Journal
Abstract
In this paper, we shall consider some properties of the metric projection as a set valued mapping. For a set G in a metric space E, the mapping 𝜋G; x → 𝜋G(x) of E into 2G is called set valued metric projection of E onto G. We investigated the properties related to the projection PS(·)(·) and 𝜋S(·)(·) as one-sided best simultaneous approximations.
Keywords
Metric projection; Chebyshev subspace; best simultaneous approximation; upper semi-continuous;
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