On a new geometric constant related to the modulus of smoothness of a Banach space

We shall introduce a new geometric constant A(X) of a Banach space X,which is closely related to the modulus of smoothness ρX(τ),and investigate it in relation with the constant A2(X) by Baronti et al.,the von Neumann–Jordan constant CNJ(X) and the James constant J(X).A sequence of recent results on these constants as well as some other geometric constants will be strengthened and improved.     

Duals of Hardy Spaces of B-valued Martingales for 0<r≤1

The dual of B-valued martingale Hardy space Hs(p)r(B) with small index 0 r ≤ 1,which is associated with the conditional p-variation of B-valued martingale,is characterized.In order to obtain the results,a new type of Campanato spaces for B-valued martingales is introduced and the classical technique of atomic decompositions is improved.Some results obtained here are connected closely with the p-uniform smoothness and q-uniform convexity of the underlying Banach space.     

支撑函数与Banach空间范数的可微性

In this paper,we defined a new continuity of supporting function and studyed a new convexity,smoothness of Banach Space and from this we studyed the relations among such convexity,smoothness and differentiability of the norm of Banach Space.     

ε-WEAKLY CHEBYSHEV SUBSPACES OF BANACH SPACES

We will define and characterize c-weakly Chebyshev subspaces of Banach spaces. We will prove that all closed subspaces of a Banach space X are ε-weakly Chebyshev if and only if X is reflexive.     

GENERALIZED ROSENTHAL＇S INEQUALITY FOR BANACH-SPACE-VALUED MARTINGALES

A generalized Rosenthal＇s inequality for Banach-space-valued martingales is proved, which extends the corresponding results in the previous literatures and characterizes the p-uniform smoothness and q-uniform convexity of the underlying Banach space. As an application of this inequality, the strong law of large numbers for Banach-space-valued martingales is also given.     

Pointwise Approximation Theorems for Combinations and Derivatives of Bernstein Polynomials

We establish the pointwise approximation theorems for the combinations of Bernstein polynomials by the rth Ditzian-Totik modulus of smoothness wФ^r（f, t） where Ф is an admissible step-weight function. An equivalence relation between the derivatives of these polynomials and the smoothness of functions is also obtained.     

ε-PSEUDO CHEBYSHEV AND ε- QUASI CHEBYSHEV SUBSPACES OF BANACH SPACES

We will define and characterize ε-pseudo Chebyshev and ε-quasi Chebyshev subspaces of Banach spaces. We will prove that a closed subspace W is ε-pseudo Chebyshev if and only if W is ε-quasi Chebyshev.     

Fractional Smoothness of Some Stochastic Integrals

We study the fractional smoothness in the sense of Malliavin calculus of stochastic integrals of the form ∫0^1Ф（Xs）dXs, where Xs is a semimartingale and Ф belongs to some fractional Sobolev space over R.     

On the Weak＊ Drop Property for Polar of Closed Bounded Convex Sets

We define and study the weak* drop property for the polar of a closed bounded convex set in a Banach space which is both a generalization of the weak* drop property for dual norm in a Banach space and a characterization of the sub-differentialmapping x→эp(x) from S(X) into 2^S(X*) that is norm upper semi-continuous and norm compact-valued.     

On the Extension of Isometries between Unit Spheres of E and C（Ω）

In this paper,we study the extension of isometries between the unit spheres of some Banach spaces E and the spaces C(Ω). We obtain that if the set sm.S1(E) of all smooth points of the unit sphere S1(E) is dense in S1(E),then under some condition,every surjective isometry V0 from S1(E) onto S1(C(Ω)) can be extended to be a real linearly isometric map V of E onto C(Ω).From this resultwe also obtain some corollaries. This is the first time we study this problem on different typical spaces,and the method of proof is also very different too.     

K-非常凸空间

本文引入了一种新的K凸空间K-非常凸空间,及其对偶空间K-非常光滑空间,它们分别是非常凸空间和非常光滑空间的推广但又严格弱于非常凸空间和非常光滑空间,因此它们又有许多独特的性质.本文讨论了它们的一些特性及与其它K凸性和K光滑性的关系,推广了[3]、[6]、[7]、[8]中的一些结果.     

切片与Banach空间的凸性,光滑性

本文用单位球的切片统一且简捷地处理Ｂａｎａｃｈ空间的（局部）Ｋ一致凸、近一致凸、近一致光滑性;定义Ｂａｎａｃｈ空间的（局部）Ｋ一致光滑、局部近一致凸、局部近一致光滑、近－强凸、近－强光滑性等概念,并讨论上述凸性,光滑性的关系及性能。     

关于Banach空间k一致凸及k一致光滑性

用统一且简洁形式刻画、定义了Banach空间的(局部)k一致凸、k-强凸、ω-强凸性.给出(局部)k一致光滑性概念,并讨论了上述空间的关系及性质.     

局部K一致光滑(LKUS)的商遗传性

在不自反的Banach空间中,利用弱*拓扑的理论,证明了局部K一致光滑(LKU S)在商空间中具有遗传性.     

Norm-to-Weak Upper Semi-Continuity of the Duality and Pre-Duality Mappings

We show that when the duality map is norm-to-weak upper semi-continuous at some point of a dual space, the pre-duality map shares this property. We show that if x is a point of very smoothness of a Banach space X, it fails in general to be a point of very smoothness of the bidual X ^**. This cannot happen however if the bidual X ^** is a Grothendieck space.     

二次对偶空间的k-光滑性特性

深入研究了Banach空间X的二次对偶空间的k-光滑性,给出了Banach空间X的二次对偶空间为k-光滑的若干特征刻画.     

Supporting Functions and The Differentiabilities of the Norms on Banach Spaces

ＳｕｐｐｏｒｔｉｎｇＦｕｎｃｔｉｏｎｓａｎｄＴｈｅＤｉｆｆｅｒｅｎｔｉａｂｉｌｉｔｉｅｓｏｆｔｈｅＮｏｒｍｓｏｎＢａｎａｃｈＳｐａｃｅｓ￥ＷａｎｇＪｉａｎｇｅｎ（王建根）（ＬｕｏｙａｎｇＴｅａｃｈｅｒ＇ｓＣｏｌｌｅｇｅ）Ａｂｓｔｒａｃｔ：Ｉｎｔｈｉｓ...     

置换空间P_XX_n中的Hahn-Banach光滑性

本文中我们给出了置换空间ＰＸＸｎ中（弱）Ｈａｈｎ－Ｂａｎａｃｈ光滑性提升性质，它们是ｌｐ（Ｘｎ）中相应结果的推广（１＜ｐ＜∞）．     

Functions related to convexity and smoothness of normed spaces

We introduce a few functions related to convexity and smoothness of normed spaces. Those functions turn out to be moduli of convexity or smoothness or play an intermediate role. We calculate the exact formulas for introduced functions in some classical Banach spaces. An application to geometry of normed spaces is also indicated.     

几类B值小指标鞅空间的原子分解

本文对几类B值小指标鞅空间建立了原子分解定理,利用原子分解讨论了它们之间的相互嵌入关系,其原子分解的存在性和它们之间的关系均与Banach空间的凸性和光滑性有密切联系.