[KSCI] Korea Science Citation Index Service

http://dx.doi.org/10.14317/jami.2021.437

EXPANSION THEORY FOR THE TWO-SIDED BEST SIMULTANEOUS APPROXIMATIONS

RHEE, HYANG JOO (Department of Mathematics, College of Natural Sciences, Duksung Women's University)

Publication Information

Journal of applied mathematics & informatics / v.39, no.3_4, 2021 , pp. 437-442 More about this Journal

Abstract

In this paper, we study the characterizations of two-sided best simultaneous approximations for ℓ-tuple subset from a closed convex subset of ℝ^m with ℓ^m₁(w)-norm. Main fact is, k^* is a two-sided best simultaneous approximation to F from K if and only if there exist f₁, …, f_p in F, for any k ∈ K ${\mid}{\sum\limits_{i=1}^{m}}sgn(f_{ji}-k^*_i)k_iw_i{\mid}{\leq}\;{\sum\limits_{i{\in}Z(f_j-k^*)}}\;{\mid}k_i{\mid}w_i$ for each j = 1, …, p and 𝐰 ∈ W.

Keywords

Best simultaneous approximation; two-sided best simultaneous approximation;

Citations & Related Records

Reference

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