A new geometrical constant of Banach spaces and the uniform normal structure

• Autorzy: Mitani K-I. , Saito K-S.
• Języki publikacji: EN

Abstrakty

EN

We introduce and study a new geometrical constant γXψ of a Banach space X, by using the notion of ψ-direct sum given in [Y. Takahashi, M. Kato and K.-S. Saito, J. Inequal. Appl. 7 (2002), 179-186]. At rst, we characterize uniform non- squareness in terms γXψ Moreover, we consider Banach spaces having uniform normal structure.

Słowa kluczowe

EN

absolute norm; [psi]-direct sum; uniformly non-square space; uniform normal structure

• Wydawca: Polskie Towarzystwo Matematyczne
• Czasopismo: Commentationes Mathematicae
• Rocznik: 2009
• Tom: Vol. 49, [Z] 1
• Strony: 3--13
• Opis fizyczny: Bibliogr. 18 poz.

Twórcy

autor

Mitani K-I.

autor

Saito K-S.

• Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Niigata Institute of Technology Kashiwazaki, Niigata 945-1195, Japan,

Bibliografia

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