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131.
Fuzzy semirings     
In this paper we initiate the study of fuzzy semirings and fuzzy A-semimodules where A is a semiring and A-semimodules are representations of A. In particular, semirings all of whose ideals are idempotent, called fully idempotent semirings, are investigated in a fuzzy context. It is proved, among other results, that a semiring A is fully idempotent if and only if the lattice of fuzzy ideals of A is distributive under the sum and product of fuzzy ideals. It is also shown that the set of proper fuzzy prime ideals of a fully idempotent semiring A admits the structure of a topological space, called the fuzzy prime spectrum of A.  相似文献   
132.
On the product of oblique projectors   总被引:4,自引:0,他引:4  
In this paper we show that for two projectors (idempotents) P1 and P2, idempotency of the product P1P2 is equivalent to the coincidence of the range of P1 P2 and a certain subspace, which only depends on the onto-and along-spaces of P1 and P2. Some further investigations are made, and necessary and sufficient conditions for the commutativity of two projectors are given.  相似文献   
133.
Bernd Billhardt 《代数通讯》2013,41(9):3521-3532
A semigroup S is said to have an associate subgroup G if, for each s ∈ S, there is a unique s* ∈ G such that ss*s = s. If the identity 1 G of G is medial, i.e., c1 G c = c holds for each c being a product of idempotents, we show that S is isomorphic to a certain subsemigroup of a semidirect product of an idempotent generated semigroup C by G. If additionally S is orthodox, we may choose C to be a band, belonging to the band variety, generated by the band of idempotents of S.  相似文献   
134.
The aim of this article is to introduce the notion of Hom-Lie color algebras. This class of algebras is a natural generalization of the Hom-Lie algebras as well as a special case of the quasi-hom-Lie algebras. In the article, homomorphism relations between Hom-Lie color algebras are defined and studied. We present a way to obtain Hom-Lie color algebras from the classical Lie color algebras along with algebra endomorphisms and offer some applications. Also, we introduce a multiplier σ on the abelian group Γ and provide constructions of new Hom-Lie color algebras from old ones by the σ-twists. Finally, we explore some general classes of Hom-Lie color admissible algebras and describe all these classes via G–Hom-associative color algebras, where G is a subgroup of the symmetric group S 3.  相似文献   
135.
We study absolute valued algebras with involution, as defined in Urbanik (1961 Urbanik , K. ( 1961 ). Absolute valued algebras with an involution . Fundamenta Math. 49 : 247258 . [Google Scholar]). We prove that these algebras are finite-dimensional whenever they satisfy the identity (x, x 2, x) = 0, where (·, ·, ·) means associator. We show that, in dimension different from two, isomorphisms between absolute valued algebras with involution are in fact *-isomorphisms. Finally, we give a classification up to isomorphisms of all finite-dimensional absolute valued algebras with involution. As in the case of a parallel situation considered in Rochdi (2003 Rochdi , A. ( 2003 ). Eight-dimensional real absolute valued algebras with left unit whose automorphism group is trivial . Int. J. Math. Math. Sci. 70 : 44474454 .[Crossref] [Google Scholar]), the triviality of the group of automorphisms of such an algebra can happen in dimension 8, and is equivalent to the nonexistence of 4-dimensional subalgebras.  相似文献   
136.
实幂等矩阵的伴随矩(英)   总被引:4,自引:2,他引:4  
AnAdjointMatrixofaRealIdempotentMatrixJinBaiKim(Dept.ofMath.,WestVirginiaUniversityMorgantown,WV26506,USA)HeeSikKim(Dept.ofMa...  相似文献   
137.
设F是特征2的域.本文确定F上n×n矩阵保幂等性的可逆的线性算子的半群H(F)的结构,同时回答了文献[1]提出的两个未解决的问题.  相似文献   
138.
139.
140.
倪翔飞  郭小江 《数学学报》2018,61(1):107-122
本文在正则半群上引入弱中间幂等元和拟中间幂等元,着重探讨了这两类幂等元的性质特征.构造了若干具有弱(拟)中间幂等元的正则半群,确定了弱中间幂等元和拟中间幂等元之间的关系,给出了弱中间幂等元和拟中间幂等元各自的等价判定,利用拟中间幂等元刻画了纯正半群.最后,得到了构造具有拟中间幂等元的正则半群的一般途径,并在此基础上进一步给出了判定正则半群是否具有乘逆断面的方法.  相似文献   
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