假设X是一个实Banach 空间,S(X) 是单位球面.作者引进了一个新的几何参数 H(X),讨论了 H(X) 和 Neumann-Jordan 常数 CNJ(X) 的性质以及 H(X) 和其他几何常数的关系.本文主要结果是:H(X)＜2 或 CNJ(X)＜4/5 推出一致正规结构.%Let X be a Banach space, S(X) be the unit sphere of X. A geometric parameter H(X) =Sup{‖x+y‖∧‖2x-y‖, for any x,y, and x-y∈S(X)} is introduced; the properties of H(X) and Neumann-Jordan constant CNJ(X),and the relationship between H(X) and other geometric concepts are discussed. The main result is that either H(X)＜2, or CNJ(X)＜4/5 implies normal structure.
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