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991.
A right module M over a ring R is said to be ADS if for every decomposition M = ST and every complement T′ of S, we have M = ST′. In this article, we study and provide several new characterizations of this new class of modules. We prove that M is semisimple if and only if every module in σ[M] is ADS. SC and SI rings also characterized by the ADS notion. A ring R is right SC-ring if and only if every 2-generated singular R-module is ADS.  相似文献   
992.
The purpose of this article is to give two random spectral theorems of self-adjoint random linear operators on complete complex random inner product modules.  相似文献   
993.
Positivity in *-algebras can be defined either algebraically, by quadratic modules, or analytically, by *-representations. By the induction procedure for *-representations, we can lift the analytical notion of positivity from a *-subalgebra to the entire *-algebra. The aim in this article is to define and study the induction procedure for quadratic modules. The main question is when a given quadratic module on the *-algebra is induced from its intersection with the *-subalgebra. This question is very hard even for the smallest quadratic module (i.e. the set of all sums of hermitian squares) and will be answered only in very special cases.  相似文献   
994.
In this article, we investigate some properties of right core inverses. Particularly, new characterizations and expressions for right core inverses are given, using projections and {1, 3}-inverses. Also, we introduced and investigated a new generalized right core inverse which is called right pseudo core inverse. Then, we provide the relation schema of (one-sided) core inverses, (one-sided) pseudo core inverses, and EP elements.  相似文献   
995.
Abstract

We show that the multiplication algebra of a nondegenerate Jordan algebra is a semiprime algebra.  相似文献   
996.
Brent Everitt 《代数通讯》2013,41(6):1817-1832
A long standing conjecture (attributed to Graham Higman) asserts that each of the triangle groups △(p,q,r)for 1/p+1/q+1/r>1 contains among its homomorphic images all but finitely many of the alternating or symmetric groups. This phenomenon has been termed property H by Mushtaq and Servatius [9]. The work of several authors over the last decade and a half has shown that for any value of q, there are only finitely many r such that△(2,q,r) fails to have property H. In this paper, the techniques used by these authors are generalised to handle the possinblity that p is odd, and as a result, it is shown that for any q≧3, there are only finitely many r such that △(3,q,r)fails to have property H.  相似文献   
997.
Let R be an associated ring not necessarily with identity, M a left R-module having the property (F), and (S, ≤) a strictly totally ordered monoid which is also artinian and finitely generated. It is shown that the module [M S,≤] consisting of generalized inverse polynomials over M is an artinian left [[R S,≤]]-module if and only if M is an artinian left R-module.  相似文献   
998.
杨曼丽 《数学研究》2006,39(1):32-35
引进了一新模类-完全平坦模(每一个商模平坦).并得到了:令M是平坦左R-模,RM是完全平坦模当且仅当RM的所有子模是纯的当且仅当每一个右R-模A是M-平坦的.同时本文用完全平坦模刻画了V.N.正则环.  相似文献   
999.
A theory of monoids in the category of bicomodules of a coalgebra C or C-rings is developed. This can be viewed as a dual version of the coring theory. The notion of a matrix ring context consisting of two bicomodules and two maps is introduced and the corresponding example of a C-ring (termed a matrix C -ring) is constructed. It is shown that a matrix ring context can be associated to any bicomodule which is a one-sided quasi-finite injector. Based on this, the notion of a Galois module is introduced and the structure theorem, generalising Schneider’s Theorem II [Schneider, Isr. J. Math., 72:167–195, 1990], is proven. This is then applied to the C-ring associated to a weak entwining structure and a structure theorem for a weak A-Galois coextension is derived. The theory of matrix ring contexts for a firm coalgebra (or infinite matrix ring contexts) is outlined. A Galois connection associated to a matrix C-ring is constructed. Dedicated to Stef Caenepeel on the occasion of his 50th birthday.  相似文献   
1000.
首先给出在随机赋范模中子集的随机最远点的概念.进一步,利用随机一致凸性和经典一致凸性之间的联系证明了下面的结果:令(E,||·||)为完备的随机一致凸的随机赋范模,S为E中几乎处处有界并在(ε, λ)一拓扑下的闭子集,则具有S中随机最远点的集合稠于E.  相似文献   
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