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861.
Wolfgang Rump 《Applied Categorical Structures》2009,17(2):153-174
We give a axiomatic treatment of the absolute in the category of all topological spaces and characterize it as a cover with
respect to the full subcategory of extremally disconnected spaces. As an application, we obtain the strongly projectable hull
of an abelian l-group as a unique lifting of the absolute of its spectrum.
Dedicated to B. V. M. 相似文献
862.
It is proved that every subspace of James Tree space (JT) with non-separable dual contains an isomorph of James Tree complemented in JT. This yields that every complemented subspace of JT with non-separable dual is isomorphic to JT. A new JT like space denoted as TF is defined. It is shown that every subspace of James Function space (JF) with non-separable dual contains an isomorph of TF. The later yields that every subspace of JF with non-separable dual contains isomorphs of c0 and ?p for 2?p<∞. The analogues of the above results for bounded linear operators are also proved. 相似文献
863.
Martin Rasmussen 《Proceedings of the American Mathematical Society》2008,136(3):1045-1055
Morse decompositions provide inside information about the global asymptotic behavior of dynamical systems on compact metric spaces. Recently, the existence of Morse decompositions for nonautonomous dynamical systems was proved by restricting attention to the past or the future of the system, but in general, such a construction is not realizable for the entire time. In this article, it is shown that all-time Morse decompositions can be defined for linear systems on the projective space. Moreover, the dynamical properties are discussed and an analogue to the Theorem of Selgrade is proved.
864.
865.
The inversion of strong scatterer embedded in the half-space is an important problem in engineering and a very difficult nonlinear
problem in mathematics, for which the Born iterative method is of no effect. In this paper the moment method is used in the
discretization procedure. A numerical approach is presented by employing the regularization technique and DBI (distorted Born
iterative) method. The simulation results show that the approach presented is efficient.
Project supported by the Research Fund for the Doctoral Program of Higher Education (RFDP: 98048705). 相似文献
866.
给出了Marcinkiewicz积分在Herz型Hardy空间上的有界性证明。即当n(1 - 1q) ≤α 相似文献
867.
利用合意空间(ConsensusSpace)理论给出了一个群的C模糊子群的定义.指出这种模糊子群实际上是基于t范(Tm范)的模糊子群.证明了Rosenfeld的模糊子群是C模糊子群,且每一个C模糊子群都与一类特殊的C模糊子群同构.从而为模糊子群提供了新的理论基础. 相似文献
868.
869.
Using a new method based on generalized sections of feasible sets, we obtain optimality conditions for vector optimization
of objective multifunctions with multivalued constraints.
The authors express their sincere gratitude to Professor F. Giannessi and the referees for comments and valuable suggestions.
The second author was partially supported by the Center of Excellence for Mathematics (University of Isfahan). 相似文献
870.