The James and von Neumann-Jordan type constants and uniform normal structure in Banach spaces
نویسنده
چکیده مقاله:
Recently, Takahashi has introduced the James and von Neumann-Jordan type constants. In this paper, we present some sufficient conditions for uniform normal structure and therefore the fixed point property of a Banach space in terms of the James and von Neumann-Jordan type constants and the Ptolemy constant. Our main results of the paper significantly generalize and improve many known results in the recent literature.
منابع مشابه
On the James Type Constant and Von Neumann–jordan Constant for a Class of Banaś–fra̧czieck Type Spaces
As a generalization of Banaś-Fra̧czieck space, the space Xλ ,p that denotes R 2 endowed with the norm ‖x‖λ ,p = max{λ |x1 |,‖x‖p} for λ > 1 , p 1 and x = (x1,x2) ∈ R2 is well defined. In this note, the exact value of the the James type constants JXλ ,p ,t(1) and von Neumann-Jordan constant CNJ (Xλ ,p) about this space for p 2 are investigated.
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عنوان ژورنال
دوره 8 شماره 1
صفحات 113- 122
تاریخ انتشار 2017-06-05
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