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31.
关于非齐次m阶马氏信源的渐近均分割性 总被引:4,自引:0,他引:4
本文研究非齐次m阶马氏信源的渐近均分割性,首先我们得到关于此种信源m 1元函数的一类强极限定理,作为推论,得到关于任意非齐次m阶马氏信源状态和熵密度的几个极限定理,最后得到一类非齐次m阶马氏信源的渐近均分割性。 相似文献
32.
四溴双酚A锑铝双金属化合物的合成及其阻燃性能 总被引:1,自引:0,他引:1
以四溴双酚A(TBA)合成了在水和空气中稳定的四溴双酚A合锑铝双金属化合物(TBASA).通过IR、1HNMR和元素分析予以表征,并研究了其对聚乙烯(PE)和聚环氧乙烷(PEO)的阻燃性能.结果表明,这种分子中含有溴、锑和铝的化合物,对聚乙烯和聚环氧乙烷等高聚物材料有高的阻燃性能与消烟效果. 相似文献
33.
A. Gorban' 《Mathematical and Computer Modelling》2002,35(13):7047-1370
An explicitly solvable Riabouchinsky model with a partially penetrable obstacle is introduced. This model applied to the estimation of the efficiency of free flow turbines allows us to take into account the pressure drop past the lamina. 相似文献
34.
S.V. Astashkin F.A. Sukochev 《Journal of Mathematical Analysis and Applications》2007,336(2):1231-1258
We catalogue all Marcinkiewicz function and sequence spaces with the Banach-Saks property and present necessary and sufficient conditions for a wide subclass of spaces to possess the p-Banach-Saks property, 1<p<∞. We apply our results to several open problems. 相似文献
35.
On the properties of solutions to the Goursat-Darboux problem with boundary and distributed controls
N. I. Pogodaev 《Siberian Mathematical Journal》2007,48(5):897-912
We consider a control system described by the Goursat-Darboux equation. The system is controlled by distributed and boundary controls. The controls are subject to the constraints given as multivalued mappings with closed, possibly nonconvex, values depending on the phase variable. Alongside the initial constraints, we consider the convexified constraints and the constraints whose values are the extreme points of the convexified constraints. We study the questions of existence of solutions and establish connections between the solutions under various constraints. 相似文献
36.
M. Dubé C. Daneault V. Vuorinen M. Alava M. Rost 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,56(1):15-26
We investigate the structure and dynamics of the interface between
two immiscible liquids in a three-dimensional disordered porous
medium. We apply a phase-field model that includes explicitly
disorder and discuss both spontaneous and forced imbibition.
The structure of the interface is dominated by a length scale
ξ× which arises from liquid conservation. We further show
that disorder in the capillary and permeability act on different
length scales and give rise to different scalings and
structures of the interface properties. We conclude with a
range of applications. 相似文献
37.
The fixed point property for multivalued nonexpansive mappings 总被引:1,自引:0,他引:1
T. Domínguez Benavides 《Journal of Mathematical Analysis and Applications》2007,328(2):1471-1483
We show some properties concerning geometrical constants of Banach spaces which imply the existence of fixed points for multivalued nonexpansive mappings and we study the relationship between these properties. 相似文献
38.
Yi Lin 《Advances in Mathematics》2007,208(2):699-709
In this paper we construct six-dimensional compact non-Kähler Hamiltonian circle manifolds which satisfy the strong Lefschetz property themselves but nevertheless have a non-Lefschetz symplectic quotient. This provides the first known counterexamples to the question whether the strong Lefschetz property descends to the symplectic quotient. We also give examples of Hamiltonian strong Lefschetz circle manifolds which have a non-Lefschetz fixed point submanifold. In addition, we establish a sufficient and necessary condition for a finitely presentable group to be the fundamental group of a strong Lefschetz manifold. We then use it to show the existence of Lefschetz four-manifolds with non-Lefschetz finite covering spaces. 相似文献
39.
Mitre C. Dourado Fábio Protti Jayme L. Szwarcfiter 《Discrete Applied Mathematics》2007,155(18):2435-2443
Let p?1 and q?0 be integers. A family of sets F is (p,q)-intersecting when every subfamily F′⊆F formed by p or less members has total intersection of cardinality at least q. A family of sets F is (p,q)-Helly when every (p,q)-intersecting subfamily F′⊆F has total intersection of cardinality at least q. A graph G is a (p,q)-clique-Helly graph when its family of (maximal) cliques is (p,q)-Helly. According to this terminology, the usual Helly property and the clique-Helly graphs correspond to the case p=2,q=1. In this work we present a characterization for (p,q)-clique-Helly graphs. For fixed p,q, this characterization leads to a polynomial-time recognition algorithm. When p or q is not fixed, it is shown that the recognition of (p,q)-clique-Helly graphs is NP-hard. 相似文献
40.