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71.
<正>Categorification of Integrable Representations of Quantum Groups Hao ZHENG Abstract We eategorify the highest weight integrable representations and their tensor prod—ucts of a symmetric quantum Kac—Moody algebra.As a byproduct,we obtain a geometric realization of Lusztig's canonical bases of these representations as well as a new positivity result.The main ingredient in the underlying geometric construction is a class of micro-local perverse  相似文献   
72.
73.
与全钒等双液流电池相比,沉积型单液流电池不使用离子交换膜等昂贵材料,结构简化,比能量提高,适合于不同规模的储能场合,研究渐多.本文介绍了沉积型单液流电池的原理与特点及其结构组成,以笔者实验室工作为主,综述了各沉积型单液流电池新体系的研究进展及存在的问题,并指出目前单液流电池待解决的问题是高比容量、高稳定性电极材料和电堆...  相似文献   
74.
<正>Similarity Degrees for the Crossed Product of yon Neumann Algebras Jin Song WU Wen Ming WU Abstract In this paper,we will estimate an upper bound for the similarity degree of the crossed product of a hyperfinite finite yon Neumann algebra by weakly compact action of an infinite discrete group.We will also improve some upper bounds for similarity degrees of some finite von Neumann algebras.  相似文献   
75.
X荧光光谱仪测定炼钢用铝条试样中的8个元素   总被引:3,自引:0,他引:3  
张伟超 《光谱实验室》1999,16(2):191-193
本文报导X荧光光谱仪,通过采用聚四氟乙烯制成孔径10mm的试样盒,测定炼钢用铝条试样,方法简便,快速,准确。  相似文献   
76.
<正>Vitali Type Convergence Theorems for Banach Space Valued Integrals Marek BALCERZAK Kazimierz MUSIAL Abstract Let(Ω,∑,μ)be a complete probability space and let X be a Banach space.We introduce the notion of scalar equi-convergence in measure which being applied to sequences of Pettis integrable functions generates a new convergence theorem.We also obtain a Vitali type I-convergence theorem for Pettis integrals where I is an ideal on N.On Universally Left-stability ofε-Isometry  相似文献   
77.
We consider the chromatic number of a family of graphs we call box graphs, which arise from a box complex in nn-space. It is straightforward to show that any box graph in the plane has an admissible coloring with three colors, and that any box graph in nn-space has an admissible coloring with n+1n+1 colors. We show that for box graphs in nn-space, if the lengths of the boxes in the corresponding box complex take on no more than two values from the set {1,2,3}{1,2,3}, then the box graph is 33-colorable, and for some graphs three colors are required. We also show that box graphs in 3-space which do not have cycles of length four (which we call “string complexes”) are 33-colorable.  相似文献   
78.
Let X be a partially ordered real Banach space, let a,bX with ab. Let φ be a bounded linear functional on X. We say that X satisfies the box-optimization property (or X is a BOP space) if the box-constrained linear program: max 〈φ,x〉, s.t. axb, has an optimal solution for any φ,a and b. Such problems arise naturally in solving a class of problems known as interval linear programs. BOP spaces were introduced (in a different language) and systematically studied in the first author’s doctoral thesis. In this paper, we identify new classes of Banach spaces that are BOP spaces. We present also sufficient conditions under which answers are in the affirmative for the following questions:
  1. (i)
    When is a closed subspace of a BOP space a BOP space?
     
  2. (ii)
    When is the range of a bounded linear map a BOP space?
     
  3. (iii)
    Is the quotient space of a BOP space a BOP space?
     
  相似文献   
79.
A study is made of two classes of product topologies on powers of spaces: the general box product topologies, and the general uniform product topologies. Some examples are given and some results are shown about the properties of these general product spaces. This is applied to show that certain spaces of continuous functions with the fine topology are homeomorphic to box product spaces, and certain spaces of continuous functions with the uniform topology are homeomorphic to uniform product spaces.  相似文献   
80.
We show that every box space of a virtually nilpotent group has asymptotic dimension equal to the Hirsch length of that group.  相似文献   
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