대한수학회보 (Bulletin of the Korean Mathematical Society)

  • 제50권2호
  • /
  • Pages.417-430
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  • 2013
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  • 1015-8634(pISSN)
  • /
  • 2234-3016(eISSN)
대한수학회 (Korean Mathematical Society)
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CHARACTERIZATIONS OF GEOMETRICAL PROPERTIES OF BANACH SPACES USING ψ-DIRECT SUMS

  • Zhang, Zhihua (School of Mathematical Sciences University of Electronic Science and Technology of China) ;
  • Shu, Lan (School of Mathematical Sciences University of Electronic Science and Technology of China) ;
  • Zheng, Jun (School of Mathematics and Statistics Lanzhou University) ;
  • Yang, Yuling (School of Mathematical Sciences University of Electronic Science and Technology of China)
  • 투고 : 2011.09.08
  • 발행 : 2013.03.31
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초록

Let X be a Banach space and ${\psi}$ a continuous convex function on ${\Delta}_{K+1}$ satisfying certain conditions. Let $(X{\bigoplus}X{\bigoplus}{\cdots}{\bigoplus}X)_{\psi}$ be the ${\psi}$-direct sum of X. In this paper, we characterize the K strict convexity, K uniform convexity and uniform non-$l^N_1$-ness of Banach spaces using ${\psi}$-direct sums.

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과제정보

연구 과제 주관 기관 : Nation Natural Science Foundation of China

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