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31.
主要讨论作用在复Hilbert空间弱闭 AlgN-模上的线性保秩映射,并给出在各种情况下保秩一性线性映射的刻画.作为应用,最后讨论了弱闭 AlgN-模上的模同构,并得出这样的同构是平凡的. 相似文献
32.
In this note, we enumerate all nonisomorphic 3‐factorizations of K10. © 2001 John Wiley & Sons, Inc. J Combin Designs 9: 379–383, 2001 相似文献
33.
Assume X is a normed space,every x * ∈ S(X*) can reach its norm at some point in B(X),and Y is a β-normed space.If there is a quotient space of Y which is asymptotically isometric to l β,then L(X,Y) contains an asymptotically isometric copy of l β.Some sufficient conditions are given under which L(X,Y) fails to have the fixed point property for nonexpansive mappings on closed bounded β-convex subsets of L(X,Y). 相似文献
34.
Motivated by a general dilation theory for operator-valued measures, framings and bounded linear maps on operator algebras, we consider the dilation theory of the above objects with special structures. We show that every operator-valued system of imprimitivity has a dilation to a probability spectral system of imprimitivity acting on a Banach space. This completely generalizes a well-known result which states that every frame representation of a countable group on a Hilbert space is unitarily equivalent to a subrepresentation of the left regular representation of the group. We also prove that isometric group representation induced framings on a Banach space can be dilated to unconditional bases with the same structure for a larger Banach space. This extends several known results on the dilations of frames induced by unitary group representations on Hilbert spaces. 相似文献
35.
36.
本文利用有向图理论研究了Xn矩阵的特性,给出了X2m矩阵类的快速构造方法,证明了拉丁方矩阵D[X2m]数目的下界估计是:2m(2m)! ∑^mi=2[(2m)!]^2/П^ij=1Kj!П^rj=1bj!。 相似文献
37.
38.
We will be mainly concerned with some important fiber spaces over Teichmüller spaces, including the Bers fiber space and Teichmüller
curve, establishing an isomorphism theorem between “punctured” Teichmüller curves and determining the biholomorphic isomorphisms
of these fiber spaces. 相似文献
39.
Stanisław Wroński 《Mathematica Slovaca》2007,57(4):359-368
In [ANISZCZYK, B.-FRANKIEWICZ, R.: Non homeomorphic density topologies, Bull. Polish Acad. Sci. Math. 34 (1986), 211–213] the authors constructed 2c non-homeomorphic density topologies tied to the concept of measure. In [WROŃSKI, S.: The number of non-homeomorphic I-density topologies. Institute of Mathematics of Polish Academy of Sciences. Preprint 482, December 1990, XXXIV Semester in Banach Center, Theory
of Real Functions] an analogous construction has been given for topologies tied to the concept of category. Here we present
a generalization containing both the results mentioned above. This generalization based only on the topological ideas is independent
of the concept of measure or category.
Communicated by L’ubica Holá 相似文献
40.
马国燕 《新疆大学学报(理工版)》2006,23(3):281-283
G是一个简单图,变换图G---是G的全图的补图.证明了对于给定的一个图G,G K1 K2,G---有一个完美匹配的充要条件是V(G) E(G)是偶数. 相似文献