Γ—正则半群上的若干同余

本文首先给出了Γ－正则半群上的群同余刻划。然后定义了Γ－逆半群的幂等分离核正规系，证明了Γ－逆半群上的幂等分离核正规系决定一个Γ－逆半群上的等分离同余，及Γ－逆半群上的幂等分离同余核是一个等分离核正规系。     

P-反演半群上的正则P-同余

令S(P)为P-反演半群，本文借助于P-核正规系来刻画S(P)上的强P-同余，证明了S(P)上的任一正则P-同余可以决定S(P)的一个P-核正规系；反之，S(P)的任一P-核正规系可以决定S(P)上的一个正则P-同余．     

φ-正则半群上的φ-同余(英文)

给出了-正则半群内的-核正规系统的一个等价刻划并用-核正规系统描述了-正则半群上的强-同余．     

P-完全正则半群

求证具有强半格结构的完全正则半群成为P-完全正则半群的充分条件.利用半群的强半格结构以及同余的性质.完全单半群的强半格-正规群带是P-完全正则半群.矩形群的强半格正规纯正群类ONBG,左群的强半格左正规纯整群类LONBG,群的强半格Clifford半群类,矩形带的强半格正规带类NB,都具有性质P.     

P-正则半群上的P-同余

给出了P-正则半群内的P-核正规系统的一个等价刻划并用P-核正规系统描速了P-正则半群上的强P-同余。     

拟完全正则半群的同余格上的一类关系(英文)

本文讨论拟完全正则半群的具有同一超迹的两个同余构成的同余格上的关系T,证明该关系是同余格上的完备关系,其等价类为区间.并确定对于完全正则半群同余进行关于T的底运算得到的同余.     

拟完全正则半群的同余格上的一类关系(英文)北大核心CSCD

本文讨论拟完全正则半群的具有同一超迹的两个同余构成的同余格上的关系T,证明该关系是同余格上的完备关系,其等价类为区间.并确定对于完全正则半群同余进行关于T的底运算得到的同余.     

完全正则半群上的H-相关同余

本文研究了完全正则半群上的H-相关同余.给出了完全正则半群上的H-相关同余的概念以及若干等价刻画.     

纯正半群上的强同余及Clifford同余

把Reilly对逆半群的幂等元集合的正规划分的概念推广到纯正半群,用它从另一角度刻画。了纯正半群上强同余的结构.并刻画了具有T关系的两个强同余的联和交的正则核正规系,又讨论了纯正半群上的Clifford同余,给出了最小Clifford同余的刻画.     

幂等元生成子半群为完全正则半群的拟完全正则半群

论文主要刻画了幂等元生成子半群为完全正则半群的拟完全正则半群. 并讨论了满足该类半群的一些子类.     

Regular Homomorphisms and Regular Maps

Regular homomorphisms of oriented maps essentially arise from a factorization by a subgroup of automorphisms. This kind of map homomorphism is studied in detail, and generalized to the case when the induced homomorphism of the underlying graphs is not valency preserving. Reconstruction is treated by means of voltage assignments on angles, a natural extension of the common assignments on darts. Lifting and projecting groups of automorphisms along regular homomorphisms is studied in some detail. Finally, the split-extension structure of lifted groups is analysed.     

正则关系与完全正则空间

借助于关系的某些代数性质刻画拓扑空间的完全正则性,证明了拓扑空间是完全正则的当且仅当其闭集与开集之间存在满足一定简单条件的正则关系,有限正则关系或广义有限正则关系.     

带正则*-断面的正则半群

本文给出了带正则*-断面的正则半群的若干性质,获得了带拟理想正则*-断面的正则半群的一个构造方法.利用这一构造定理,考虑了这类半群上的同余.     

Abel正则球与完全正则半群

本文分别讨论了关于结合环和半群的二个定理，并且由结合环的这二个定理推出了如下准则：结合环Ｒ是Ａｂｅｌ正则的，当且仅当Ｒ的每个拟理想是正则环．     

Regular Graphs,Eigenvalues and Regular Factors

In this article, we obtain a sufficient condition for the existence of regular factors in a regular graph in terms of its third largest eigenvalue. We also determine all values of k such that every r‐regular graph with the third largest eigenvalue at most has a k‐factor.     

Regular Paper

We study the algebraic dimension of twistor spaces of positive type over 4CP². We show that such a twistor space is Moishezon if and only if its anti-canonical class is not nef. More precisely, we show the equivalence of being Moishezon with the existence of a smooth rational curve having negative intersection number with the anticanonical class. Furthermore, we give precise information on the dimension and base locus of the fundamental linear system |-1/2|. This implies, for example, dim|-1/2K| a(Z). We characterize those twistor spaces over 4CP², which contain a pencil of divisors of degree one by the property dim|-1/2K| = 3.     

Regular closure

Regular closure is an operation performed on submodules of arbitrary modules over a commutative Noetherian ring. The regular closure contains the tight closure when both are defined, but in general, the regular closure is strictly larger. Regular closure is interesting, in part, because it is defined a priori in all characteristics, including mixed characteristic. We show that one can test regular closure in a Noetherian ring by considering only local maps to regular local rings. In certain cases, it is necessary only to consider maps to certain affine algebras. We also prove the equivalence of two variants of regular closure for a class of rings that includes .

     

Weakly Regular and Regular sets in Minkowski planes

A Regular (respectively Weakly Regular) set for an incidence structure Q is a set of points such that the identity is the only automorphism of Q which maps onto itself (respectively which fixes pointwise). In this work Weakly Regular and Regular sets in Minkowski planes are investigated.Work done within the activity of G.N.S.A.G.A. of C.N.R. and supported by 40 % grants of M.U.R.S.T.G.Rinaldi thanks Fondazione Francesco Severi and Banca Popolare dell'Etruria e del Lazio for the prize which allowed this research.     

Regular reals

Say that α is an n‐strongly c. e. (n‐strongly computably enumerable) real if α is a sum of n many strongly c. e. reals, and that α is regular if α is n‐strongly c. e. for some n. Let Sⁿ be the set of all n‐strongly c. e. reals, Reg be the set of regular reals and CE be the set of c. e. reals. Then we have: S¹ ? S² ? · · · ? Sⁿ ? · · · ? ? Reg ? CE . This gives a hierarchy of the c. e. reals. We also study the regularity of the d. c. e. reals. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)