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排序方式: 共有137条查询结果,搜索用时 473 毫秒
11.
Pei-Kee Lin 《Journal of Mathematical Analysis and Applications》2005,312(1):138-147
Let (X,F,μ) be a complete probability space, B a sub-σ-algebra, and Φ the probabilistic conditional expectation operator determined by B. Let K be the Banach lattice {f∈L1(X,F,μ):‖Φ(|f|)‖∞<∞} with the norm ‖f‖=‖Φ(|f|)‖∞. We prove the following theorems:
- (1)
- The closed unit ball of K contains an extreme point if and only if there is a localizing set E for B such that supp(Φ(χE))=X.
- (2)
- Suppose that there is n∈N such that f?nΦ(f) for all positive f in L∞(X,F,μ). Then K has the uniformly λ-property and every element f in the complex K with is a convex combination of at most 2n extreme points in the closed unit ball of K.
12.
Tiexin Guo 《Journal of Functional Analysis》2010,258(9):3024-842
The purpose of this paper is to exhibit the relations between some basic results derived from the two kinds of topologies (namely the (ε,λ)-topology and the stronger locally L0-convex topology) for a random locally convex module. First, we give an extremely simple proof of the known Hahn-Banach extension theorem for L0-linear functions as well as its continuous variant. Then we give the relations between the hyperplane separation theorems in [D. Filipovi?, M. Kupper, N. Vogelpoth, Separation and duality in locally L0-convex modules, J. Funct. Anal. 256 (2009) 3996-4029] and a basic strict separation theorem in [T.X. Guo, H.X. Xiao, X.X. Chen, A basic strict separation theorem in random locally convex modules, Nonlinear Anal. 71 (2009) 3794-3804]: in the process we also obtain a very useful fact that a random locally convex module with the countable concatenation property must have the same completeness under the two topologies. As applications of the fact, we prove that most of the previously established principal results of random conjugate spaces of random normed modules under the (ε,λ)-topology are still valid under the locally L0-convex topology, which considerably enriches financial applications of random normed modules. 相似文献
13.
In this paper, we study the quasi-neutral limit of compressible Euler-Poisson equations in plasma physics in the torus Td. For well prepared initial data the convergence of solutions of compressible Euler-Poisson equations to the solutions of incompressible Euler equations is justified rigorously by an elaborate energy methods based on studies on an λ-weighted Lyapunov-type functional. One main ingredient of establishing uniformly a priori estimates with respect to λ is to use the curl-div decomposition of the gradient. 相似文献
14.
15.
Yew-Hong Ooi 《Liquid crystals》2018,45(2):204-218
Two homologous series of λ-shaped chiral liquid crystal trimers composed of a laterally substituted benzylidene-aniline as the central core armed by two cholestryl ester moieties via odd-even alkyl spacer are synthesised. All the compounds are mesogenic exhibiting both chiral nematic (N*) and SmA phases except for trimers bearing long spacers (n = 9–10). A pronounced odd-even effect is observed on the phase transition temperatures and clearing enthalpies when the spacer length is varied in which the even-parity members show higher value. The widening of N* phase upon elongation of the alkyl spacer can be interpreted as a result of the destabilisation of SmA phase. Full recrystallisation from the cholesteric phase upon cooling is not observed for all the compounds bearing long spacer, especially oxydecanoyl spacer. Instead, the anisotropic fluid vitrified to form the cholesteric glassy state characteristic of polymer at low temperature. This finding is also evident from the polarising optical microscope whereby non-crystalline texture which resembles the Grandjean texture with various reflection colours is observed upon cooling to low temperature. The effect of the lateral substituents on the liquid-crystalline behaviour is also discussed. 相似文献
16.
在(λ,μ)-模糊子群的基础上,进一步刻画了(λ,μ)-模糊子环和理想.详细讨论了(λ,μ)-模糊子环和理想的性质,以及它们与截集的关系,给出了相应结论. 相似文献
17.
张霞 《应用泛函分析学报》2012,14(1):32-39
首先对几乎处处有界的随机线性算子的Co-半群{B(t):t≥0)利用L^0-范数的转化技巧给出一个特殊的性质.然后,基于这一性质,对与{B(t):t≥0}的随机无穷小生成元相关的一些重要的性质进行了研究,并改进了近期文献中一些已知的结果。 相似文献
18.
区间值模糊数与区间值粗糙模糊数 总被引:2,自引:0,他引:2
把经典Z.Pawlak粗糙集与区间值模糊集相结合,研究区间值模糊数的基本理论.讨论区间值模糊数的基本性质和四则运算法则及其与其它各种区间数的关系,并给出区间值模糊数的刻画定理.同时,在经典Z.Pawlak粗糙集的框架下定义实直线上的粗闭区间套,提出区间值粗糙模糊数的定义.利用模糊数的表现定理给出区间值粗糙模糊数的一个刻画. 相似文献
19.
Takayoshi Fujii Tomoyoshi Takano Hiroyuki Morita Toshiaki Yoshimura 《Tetrahedron》2006,62(41):9622-9627
The fluorination of 10-oxo-10H-5λ4,10λ4-thianthren-5-ylideneamine (2) with Selectfluor™ affords 5-fluoro-10-oxo-5,10-dihydro-5λ6,10λ4-thianthren-5-nitrile (4). The amination of 4 with morpholine gives 5-morpholino-10-oxo-5,10-dihydro-5λ6,10λ4-thianthren-5-nitrile (5). The stereochemical course of both reactions has been studied, while the configurations of their products, cis-isomer 4 and trans-5-morpholino-10-oxo-5,10-dihydro-5λ6,10λ4-thianthren-5-nitrile (trans-5) are elucidated by the use of X-ray crystallographic analyses. 相似文献
20.
研究群分次λ-双代数(Hopf代数)的一些构造,利用给定的群分次λ-双代数(Hopf代数)和群上的双特征标得到两类新的群分次λ-双代数(Hopf代数). 相似文献