Banach空间中弱收敛序列系数的估计

左占飞, 王良伟, 刘学飞, 陈晓春

数学学报 ›› 2016, Vol. 59 ›› Issue (2) : 145-150.

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数学学报 ›› 2016, Vol. 59 ›› Issue (2) : 145-150. DOI: 10.12386/A2016sxxb0014
论文

Banach空间中弱收敛序列系数的估计

    左占飞, 王良伟, 刘学飞, 陈晓春
作者信息 +

Some Estimates for the Weakly Convergent Sequence Coefficient in Banach Spaces

    Zhan Fei ZUO, Liang Wei WANG, Xue Fei LIU, Xiao Chun CHEN
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文章历史 +

摘要

利用Jordan-von Neumann型常数 C't(X),C_(X) 和弱正交系数 u(X) 对 Banach空间中的弱收敛序列系数 WCS(X)进行了估计, 从而得到空间具有正规结构的充分条件,这些结论推广了最近一些文献中的结果. 同时,还计算了Bynum空间 l2,∞, 中上述常数的取值, 来说明我们给定的条件是一个严格的推广.

Abstract

We establish two inequalities concerning the weakly convergent sequence WCS(X) and Jordan-von Neumann type constants C't(X), C_(X), which enable us to obtain some sufficient conditions for normal structure. The results obtained in this paper represent an extension as well as refinement of previous known results. Meanwhile, the Jordan-von Neumann type constants C't(X), C_(X) for the Bynum space l2,∞ are computed, and are used to show that our results are sharp.

关键词

Jordan-von Neumann型常数 / 弱正交系数 / 弱收敛序列系数 / 正规结构

Key words

Jordan-von Neumann type constant / coefficient of weak orthogonality / weakly convergent sequence coefficient / normal structure

引用本文

导出引用
左占飞, 王良伟, 刘学飞, 陈晓春. Banach空间中弱收敛序列系数的估计. 数学学报, 2016, 59(2): 145-150 https://doi.org/10.12386/A2016sxxb0014
Zhan Fei ZUO, Liang Wei WANG, Xue Fei LIU, Xiao Chun CHEN. Some Estimates for the Weakly Convergent Sequence Coefficient in Banach Spaces. Acta Mathematica Sinica, Chinese Series, 2016, 59(2): 145-150 https://doi.org/10.12386/A2016sxxb0014

参考文献

[1] Bynum W., Normal structure coefficients for Banach spaces, J. Math. Pacific, 1980, 86(2): 427-436.
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[8] Yang C. S., Wang Y. M., Some properties on Jordan-von Neumann type constant of Banach spaces, Acta Mathematica Scientia, 2012, 32A(1): 212-221.
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基金

重庆市基础与前沿研究计划资助项目(cstc2014jcyjA00022);重庆三峡学院科学研究重点项目,(14ZD09);重庆三峡学院非线性科学与系统结构重点实验室面上项目

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