Articles

ON A GENERALIZED GEOMETRIC CONSTANT AND SUFFICIENT CONDITIONS FOR NORMAL STRUCTURE IN BANACH SPACES

  • Mina DINARVAND
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  • Faculty of Mathematics, K. N. Toosi University of Technology, P. O. Box 16315-1618, Tehran, Iran

Received date: 2016-08-28

  Revised date: 2017-03-30

  Online published: 2017-10-25

Abstract

In this paper,we introduce a new geometric constant CNJ(p)(a,X) of a Banach space X,which is closely related to the generalized von Neumann-Jordan constant and analyze some properties of the constant.Subsequently,we present several sufficient conditions for normal structure of a Banach space in terms of this new constant,the generalized James constant,the generalized García-Falset coefficient and the coefficient of weak orthogonality of Sims.Our main results of the paper generalize some known results in the recent literature.

Cite this article

Mina DINARVAND . ON A GENERALIZED GEOMETRIC CONSTANT AND SUFFICIENT CONDITIONS FOR NORMAL STRUCTURE IN BANACH SPACES[J]. Acta mathematica scientia, Series B, 2017 , 37(5) : 1209 -1220 . DOI: 10.1016/S0252-9602(17)30068-1

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