期刊名称:International Journal of Mathematics and Mathematical Sciences
印刷版ISSN:0161-1712
电子版ISSN:1687-0425
出版年度:2007
卷号:2007
DOI:10.1155/2007/52382
出版社:Hindawi Publishing Corporation
摘要:In this paper, motivated by the results published by R. Khalil and A. Saleh in 2005, we study the notion of k-smooth points and the notion of k-smoothness, which are dual to the notion of k-rotundity. Generalizing these notions and combining smoothness with the recently introduced notion of unitary, we study classes of Banach spaces for
which the vector space, spanned by the state space corresponding to a
unit vector, is a closed set.