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91.
J. E. Vaughan 《Indagationes Mathematicae》2001,12(4):585
It is well known that spaces defined from a separated uniform structure with a linearly ordered base of uncountable cofinality (ωμ-metrizable spaces) are ultraparacompact and have an ortho-base, hence are non-Archimedean spaces in the sense of A. Monna. Our results concern whether certain wider classes of spaces defined from linear structures retain these properties. We construct for every regular cardinal ωμ, examples of ωμ-additive, ωμ-stratifiable spaces (i.e., ωμ-Nagata spaces) that do not have an ortho-base. We give a number of examples of linearly stratifiable spaces, one of which is related to an example of Eric K. van Douwen concerning countable box products of stratifiable spaces. 相似文献
92.
In this paper, we construct a new class of finite groups whose common divisor graphs are complete graphs, while there is no prime dividing all the nontrivial degrees. 相似文献
93.
Eiichi Bannai 《Journal of Algebraic Combinatorics》1993,2(4):327-344
We introduce the concept of fusion algebras at algebraic level, as a purely algebraic concept for the fusion algebras which appear in conformal field theory in mathematical physics. We first discuss the connection between fusion algebras at algebraic level and character algebras, a purely algebraic concept for Bose-Mesner algebras of association schemes. Through this correspondence, we establish the condition when the matrix S of a fusion algebra at algebraic level is unitary or symmetric. We construct integral fusion algebras at algebraic level, from association schemes, in particular from group association schemes, whose matrix S is unitary and symmetric. Finally, we consider whether the modular invariance property is satisfied or not, namely whether there exists a diagonal matrix T satisfying the condition (ST)3 = S
2. We prove that this property does not hold for some integral fusion algebras at algebraic level coming from the group association scheme of certain groups of order 64, and we also prove that the (nonintegral) fusion algebra at algebraic level obtained from the Hamming association scheme H(d, q) has the modular invariance property. 相似文献
94.
本文研究了具有鉴相特性g()=((1+k)sin())/(1+kcos())的三阶锁相环路方程奇点的拓扑结构. 相似文献
95.
James McLaughlin Andrew V. Sills 《Journal of Mathematical Analysis and Applications》2008,344(2):765-777
We present several new families of Rogers-Ramanujan type identities related to the moduli 18 and 24. A few of the identities were found by either Ramanujan, Slater, or Dyson, but most are believed to be new. For one of these families, we discuss possible connections with Lie algebras. We also present two families of related false theta function identities. 相似文献
96.
图T1,1,m与Q(3,n)中有路因子的充分必要条件及T1,1,m的匹配等价类 总被引:1,自引:0,他引:1
如果一个图的匹配多项式可以被一个路的匹配多项式整除,我们就称此路是该图的一个路因子,路因子在刻画图的匹配等价类,研究匹配唯一性方面有很重要的作用.本文得到了图T1,1.m与图Q(3,n)中有路因子的充分必要条件. 相似文献
97.
Ulrike Tillmann 《K-Theory》1992,6(5):457-463
Karoubi's relative Chern character is constructed as a chain map factoring through Lie algebra chains.This is part of the author's doctoral thesis, Stanford University 1990. 相似文献
98.
哈萨克文的每个字母分四种字体,用于句子的不同位置,当用计算机处理哈文信息时,每个字母间靠近程度是模糊的。本文提出一种用模糊综合评判法来评价字库,且提出改进方案的方法。 相似文献
99.
For a group G,we produce upper and lower bounds for the sum of the entries of the Brauer character table of G and the projective indecomposable character table of G.When G is a π-separable group,we show that the sum of the entries in the table of Isaacs' partial characters is a real number,and we obtain upper and lower bounds for this sum. 相似文献
100.
A classification of Bernstein algebras in dimensions n ? 4 has been made by Holgate in [2], however that article contains no classification up to isomorphism, the problem is solved by Lyubich in [4] when K = R or C, and by Cortes [1] in the general case. Also Lyubich has given in [5] a classification of the regular nonexceptional Bernstein algebra of type (3,n?3) and a classification but not up to isomorphism of nonregular nonexceptional Bernstein algebras of type (3,n ? 3) when K = C. The aim of this paper it to characterize, up to isomorphism, Bernstein algebras of type(2, n ? 2) and nonexceptional of type(3, n ?3) over a infinite commutative field K whose characteristic is different from 2. 相似文献