摘要:

The concept of infused formations, a proper subset of the saturated formations, is introduced. Localization of the infused formations is investigated with respect toOutG(H/K) for a chief factorH/Kin a groupGin conjunction with the existing formation function due to saturation. As a result, each saturated formation is contained in an infused formation, i.e. infusion creates an umbrella for saturation.

ISSN:0092-7872    

DOI:10.1080/00927879908826620

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1999

数据来源: Taylor

摘要:

LetSbe a simplicial affine semigroup such that its semigroup ringA=k[S] is Buchsbaum. We prove for suchAthe Herzog-Vasconcelos conjecture: If theA-module DerkAofk-linear derivations ofAhas finite projective dimension then it is free and henceAis a polynomial ring by the well known graded case of the Zariski-Lipman conjecture.

ISSN:0092-7872    

DOI:10.1080/00927879908826621

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1999

数据来源: Taylor

摘要:

In [1] we gave a procedure that associates to each graph Г a configurationC(Г) of symplectic type. We called this graph “a diagram for the configuration”.In the same paper we prove that certain Dynkin-like diagrams (see Example 3 below) define the reduced symplectic configurations.

ISSN:0092-7872    

DOI:10.1080/00927879908826622

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1999

数据来源: Taylor

摘要:

Our main result is that the complexity of computing linear projections of an equidimensional, but non necessarily reduced, curve(or equivalently the degree-complexity of the Gröbner basis computation for elimination orders) has its maximal value, namely Bayer’s bound mo, if and only if the smallest linear subspace containingCis a plane. If this is so, mocoincides with the degree ofCand with the degree-complexity of the reverse lexicographic ordering.

ISSN:0092-7872    

DOI:10.1080/00927879908826623

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1999

数据来源: Taylor

ISSN:0092-7872    

DOI:10.1080/00927879908826624

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1999

数据来源: Taylor

摘要:

In his 1977 paper, V.G. Kac classified the finite-dimensional simple complex Lie superalgebras. After Kac’s paper, M. Scheunert initiated the study of a generalization of Lie superalgebras - the Lie color algebras. We construct some new families of simple Lie color algebras. Following the work of A. Berele and A. Regev and A.N. Sergeev, who studied the general linear andsq(n)-series superalgebra cases, and the work of G. Benkart, C. Lee Shader, and A. Ram, who studied the orthosymplectic cases, we examine the centralizer algebras of some classical Lie superalgebras and their Lie color algebra counterparts acting on tensor space and derive Schur-Weyl duality results for these algebras and their centralizers.

ISSN:0092-7872    

DOI:10.1080/00927879908826625

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1999

数据来源: Taylor

摘要:

We study the classical problem of the existence of irreducible plane curves with given degreedand prescribed singularities of topological typesS1,…,Sr- Our main results concern substantial improvements of the leading coefficients in the asymptotically optimal sufficient conditions for complex plane curves which were found in [GLS1]. We then transfer these results to real plane curves.

ISSN:0092-7872    

DOI:10.1080/00927879908826626

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1999

数据来源: Taylor

摘要:

We describe the graded-simple modules over a semigroup-graded ring in terms of the simple modules over various component subrings. Our method utilizes the coinduction functorsCoindx.

ISSN:0092-7872    

DOI:10.1080/00927879908826627

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1999

数据来源: Taylor

摘要:

LetKbe a field of characteristicp> 0 and letDλbe an irreducible representation of the symmetric group ∑noverKcorresponding to ap-regular partition λ. We describe the composition factors in the restricted modulesfor all two part partitions λ. We use these branching rules to classify all inductive systems consisting of irreducible modulesDλwith λ having at most two parts.

ISSN:0092-7872    

DOI:10.1080/00927879908826628

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1999

数据来源: Taylor

摘要:

IfRis a commutative ring with identity andGa group, it is shown that the regular radical of the group ringRGis trivial if the regular radical ofRis trivial. This answers in the affirmative the commutative case of a question in [4]. Further, the regular radical ofRGis computed whenGis an Abelian group or whenGis locally finite and the order of each element ofGis a unit inR.

ISSN:0092-7872    

DOI:10.1080/00927879908826629

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1999

数据来源: Taylor