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71.
J. A. Yan 《Applied Mathematics and Optimization》1995,31(2):137-153
Some sharp results about Weiner and Wick products of whitenoise functionals are obtained. Using the inequality of Wick products we show to what extent scaling transformations, translations, and Sobolev differentiations can be performed on white-noise functionals.This work was supported by the National Natural Science Foundation of China. This paper is an enlargement and revised version of the paper entitled Products and Transforms of White-Noise Functionals (preprint, 1990). 相似文献
72.
M. W. Evans 《Foundations of Physics Letters》1996,9(4):397-405
The equations of free-space electrodynamics are derived directly from the Riemann curvature tensor and the Bianchi identity of general relativity by contracting on two indices to give a novel antisymmetric Ricci tensor. Within a factore/h, this is the field-strength tensor G of free-space electrodynamics. The Bianchi identity for G describes free-space electrodynamics in a manner analogous to, but more general than, Maxwell's equations for electrodynamics, the critical difference being the existence in general and special relativity of the Evans-Vigier fieldB
(3). 相似文献
73.
Bojan Magajna 《Transactions of the American Mathematical Society》1996,348(6):2427-2440
Tensor products of Calgebras over an abelian Walgebra are studied. The minimal Cnorm on is shown to be just the quotient of the minimal Cnorm on if or is exact.
74.
H. D. Junghenn 《Transactions of the American Mathematical Society》1996,348(3):1051-1073
A weakly continuous, equicontinuous representation of a semitopological semigroup on a locally convex topological vector space gives rise to a family of operator semigroup compactifications of , one for each invariant subspace of . We consider those invariant subspaces which are maximal with respect to the associated compactification possessing a given property of semigroup compactifications and show that under suitable hypotheses this maximality is preserved under the formation of projective limits, strict inductive limits and tensor products.
75.
D. H. Fremlin R. A. Johnson E. Wajch 《Proceedings of the American Mathematical Society》1996,124(9):2897-2903
A space Borel multiplies with a space if each Borel set of is a member of the -algebra in generated by Borel rectangles. We show that a regular space Borel multiplies with every regular space if and only if has a countable network. We give an example of a Hausdorff space with a countable network which fails to Borel multiply with any non-separable metric space. In passing, we obtain a characterization of those spaces which Borel multiply with the space of countable ordinals, and an internal necessary and sufficient condition for to Borel multiply with every metric space.
76.
Fang Jie 《数学学报(英文版)》1996,12(3):249-253
In this paper we introduce an algebraic concept of the product of Ockham algebras called the Braided product. We show that ifL
i
MS(i=1, 2, ,n) then the Braided product ofL
i(i=1, 2, ,n) exists if and only ifL
1, ,L
n have isomorphic skeletons. 相似文献
77.
Robert W. Baddeley 《Journal of Algebraic Combinatorics》1993,2(3):215-237
The paper addresses a part of the problem of classifying all 2-arc transitive graphs: namely, that of finding all groups acting 2-arc transitively on finite connected graphs such that there exists a minimal normal subgroup that is nonabelian and regular on vertices. A construction is given for such groups, together with the associated graphs, in terms of the following ingredients: a nonabelian simple group T, a permutation group P acting 2-transitively on a set , and a map F : Tsuch that x = x
–1 for all x
F() and such that Tis generated by F(). Conversely we show that all such groups and graphs arise in this way. Necessary and sufficient conditions are found for the construction to yield groups that are permutation equivalent in their action on the vertices of the associated graphs (which are consequently isomorphic). The different types of groups arising are discussed and various examples given. 相似文献
78.
2-氨基二甲基吡啶镉的单晶已被单晶定向的~(113)Cd核磁共振进行了研究。在CdCl_2+2-氨基二甲基吡啶中对于两个氯-四个氮的~(113)Cd的屏蔽张量元素分别是σ_(33)=368,σ_(22)=266,和σ_(11)=236×10~(-6)。 相似文献
79.
80.
本文紧紧围绕发展我国化纤新品种的现状和展望,提出由“产品先导型”向“技术先导型”、由“市场开发型”向“发展型”过渡的发展展望。按化纤新品种几种主要发展途径,侧重就我国化纤新品种的成就,如:合成新的高聚物,化学、物理(包括结构)改性和纱线、织物后整理等,特别对共聚、共混、多种复合技术改性等,进行了重点讨论。 相似文献