# Best approximations, fixed points and parametric projections

Discussiones Mathematicae, Differential Inclusions, Control and Optimization (2002)

- Volume: 22, Issue: 2, page 243-260
- ISSN: 1509-9407

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topTiziana Cardinali. "Best approximations, fixed points and parametric projections." Discussiones Mathematicae, Differential Inclusions, Control and Optimization 22.2 (2002): 243-260. <http://eudml.org/doc/271458>.

@article{TizianaCardinali2002,

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].},

author = {Tiziana Cardinali},

journal = {Discussiones Mathematicae, Differential Inclusions, Control and Optimization},

keywords = {fixed point; parametric projection; best approximation; upper semicontinuous; partially closed graph; f-approximatively compact; Oshman space},

language = {eng},

number = {2},

pages = {243-260},

title = {Best approximations, fixed points and parametric projections},

url = {http://eudml.org/doc/271458},

volume = {22},

year = {2002},

}

TY - JOUR

AU - Tiziana Cardinali

TI - Best approximations, fixed points and parametric projections

JO - Discussiones Mathematicae, Differential Inclusions, Control and Optimization

PY - 2002

VL - 22

IS - 2

SP - 243

EP - 260

AB - 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].

LA - eng

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

UR - http://eudml.org/doc/271458

ER -

## References

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