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1.
Structure of Degenerate Block Algebras   总被引:12,自引:0,他引:12  
Given a non-trivial torsion-free abelian group (A,+,Q), a field F of characteristic 0, and a non-degenerate bi-additive skew-symmetric map : A A F, we define a Lie algebra = (A, ) over F with basis {ex | x A/{0}} and Lie product [ex,ey] = (x,y)ex+y. We show that is endowed uniquely with a non-degenerate symmetric invariant bilinear form and the derivation algebra Der of is a complete Lie algebra. We describe the double extension D( , T) of by T, where T is spanned by the locally finite derivations of , and determine the second cohomology group H2(D( , T),F) using anti-derivations related to the form on D( , T). Finally, we compute the second Leibniz cohomology groups HL2( , F) and HL2(D( , T), F).2000 Mathematics Subject Classification: 17B05, 17B30This work was supported by the NNSF of China (19971044), the Doctoral Programme Foundation of Institution of Higher Education (97005511), and the Foundation of Jiangsu Educational Committee.  相似文献
2.
关于序列覆盖s映射的注记   总被引:7,自引:0,他引:7       下载免费PDF全文
李进金  蔡伟元 《数学学报》2000,43(4):757-762
本文分别给出局部可分度量空间的强序列覆盖(1序列覆盖,2序列覆盖)s映象的新国,还分别给出拓扑空间是局部可分度量空间的序列覆盖(紧覆盖)s映象的一个充分条件。  相似文献
3.
第一部分给出局部β-凸空间中的第二分离性定理和Minkowski定理及Krein-Milman定理等;第二部分得到其共轭锥上U F-有界与U B-有界等价的充要条件为原空间是次完备的.  相似文献
4.
一类带有非退化对称不变双线性型的李代数   总被引:5,自引:1,他引:4       下载免费PDF全文
朱林生  孟道骥 《数学学报》2000,43(6):1119-112
本文给出了一类带有非退化对称不变双线性型的李代数的特征性质、结构及实现。  相似文献
5.
Qualitative analysis of a stochastic ratio-dependent predator-prey system   总被引:3,自引:0,他引:3  
A stochastic ratio-dependent predator-prey model is investigated in this paper. By the comparison theorem of stochastic equations and Itô’s formula, we obtain the global existence of a positive unique solution of the ratio-dependent model. Besides, a condition for species to be extinct is given and a persistent condition is established. We also conclude that both the prey population and the ratio-dependent function are stable in time average. In the end, numerical simulations are carried out to confirm our findings.  相似文献
6.
复局部β-凸空间l~β与L~β[0,1]的共轭锥的次表示定理   总被引:2,自引:0,他引:2       下载免费PDF全文
王见勇 《数学学报》2005,48(6):1155-1166
本文研究复局部β-凸空间l~β与L~β[0,1](0<β<1)的共轭锥(l~β)_β~*与(L~β[0,1])_β~*的构造与表示问题,得到(l~β)_β~*(?)mM_β~ (T),(L~β[0,1])_β~*(?)L~∞M_β~ (I×T),称为(l~β)_β~*与(L~β[0,1])_β~*的次表示定理。  相似文献
7.
积分凸性及其应用   总被引:1,自引:0,他引:1       下载免费PDF全文
该文在Banach空间中通过向量值函数的Bochner积分引进集合与泛函的积分凸性以及集合的积分端点等概念.文章主要证明有限维凸集、开凸集和闭凸集均是积分凸集,下半连续凸泛函与开凸集上的上半连续凸泛函均是积分凸的,非空紧集具有积分端点,对紧凸集来说其积分端点集与端点集一致,最后给出积分凸性在最优化理论方面的两个应用.  相似文献
8.
In this paper, we bound the Fitting height of a solvable group by the number of zeros in a character table.

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9.
A condition for the solvability of finite groups   总被引:1,自引:1,他引:0  
A subgroup H is called ℳ-supplemented in a finite group G, if there exists a subgroup B of G such that G = HB and H 1 B is a proper subgroup of G for every maximal subgroup H 1 of H. We investigate the influence of ℳ-supplementation of Sylow subgroups and obtain a condition for solvability and p-supersolvability of finite groups. Original Russian Text Copyright ? 2009 Miao L. and Qian G. The authors were supported by the Tianyuan Fund for Mathematics of P. R. China (Grant 10626047), the NSFC, and the Qing Lan Project of the Jiangsu Province. __________ Translated from Sibirskiĭ Matematicheskiĭ Zhurnal, Vol. 50, No. 4, pp. 865–871, July–August, 2009.  相似文献
10.
Sufficient optimality conditions are obtained for a nonlinear multiple objective fractional programming problem involving η-semidifferentiable type I-preinvex and related functions. Furthermore, a general dual is formulated and duality results are proved under the assumptions of generalized semilocally type I-preinvex and related functions. Our result generalize the results of Preda [V. Preda, Optimality and duality in fractional multiple objective programming involving semilocally preinvex and related functions, J. Math. Anal. Appl. 288 (2003) 365–382] and Stancu-Minasian [I.M. Stancu-Minasian, Optimality and duality in fractional programming involving semilocally preinvex and related functions, J. Inform. Optim. Sci. 23 (2002) 185–201].  相似文献
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