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ArticleOriginal scientific text

Title

Best approximations, fixed points and parametric projections

Authors 1

Affiliations

  1. University of Perugia, Department of Mathematics and Computer Science, Via Vanvitelli, 1 - 06123 Perugia, Italy

Abstract

If f is a continuous seminorm, we prove two f-best approximation theorems for functions Φ not necessarily continuous as a consequence of our version of Glebov's fixed point theorem. Moreover, we obtain another fixed point theorem that improves a recent result of [4]. In the last section, we study continuity-type properties of set valued parametric projections and our results improve recent theorems due to Mabizela [11].

Keywords

ENG
fixed point, parametric projection, best approximation, upper semicontinuous, partially closed graph, f-approximatively compact, Oshman space

Bibliography

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Discussiones Mathematicae, Differential Inclusions, Control and Optimization
2002/22/2
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Pages:
243-260
Main language of publication
English
Received
2002-12-30
Published
2002

DOI: 10.7151/dmgt.1041

Exact and natural sciences