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61.
It is known that a C–rpp semigroup can be described as a strong semilattice of left cancellative monoids. In this paper, we introduce the class of left C–wrpp semigroups which includes the class of left C–rpp semigroups as a subclass. We shall particularly show that the semi-spined product of a left regular band and a C–wrpp semigroup forms a curler which is a left C–wrpp semigroup and vice versa. Results obtained by Fountain and Tang on C–rpp semigroups are extended and strengthened.  相似文献   
62.
The Semigroup Structure of Left Clifford Semirings   总被引:5,自引:0,他引:5  
In this paper,we generalize Clifford semirings to left Clifford semirings by means of the so-called band semirings.We also discuss a special case of this kind of semirings,that is, strong distributive lattices of left rings.  相似文献   
63.
通过引入ω-Nerode等价关系,fuzzy前逆缀ω-语言,闭左逆语言等概念来研究语言的化数性质,得到了(1)fuzzyω正则语言可由一些具有有限指标集的等价类来表示;(2)fuzzy前逆缀ω-语言是fuzzyω正则语言iff由L定义的ω-Nerode等价关系的指标集是有限的.  相似文献   
64.
张圣贵 《数学学报》1998,41(1):137-144
设G是有限群,R是有单位元的G-型分次环,S是包含在R的所有齐次元素组成的集合内的乘法封闭子集,S=x∈Gae(gx,x)a∈S,Deg(a)=g∈G{},S==x∈Gae(gx,xh)a∈S,Deg(a)=g∈G,h∈G{},MG(R)表示以G的元作为行列标的|G|阶矩阵环.本文证明了R关于S满足左Ore条件当且仅当R#G关于S满足左Ore条件当且仅当MG(R)关于S=满足左Ore条件,而且,S-1(R#G)≌(S-1R)#G和S=,-1(MG(R))≌MG(S-1R).  相似文献   
65.
Connections of some groupoid identities with the quasigroup and Latin square properties are investigated using combinatorial methods.  相似文献   
66.
This article gives a sufficient condition which guarantees the existence of a reference frame in which a multi-output nonlinear system is linearizable with a linear part depending on its outputs. Our method is based on the design of a reference frame associated with nonlinear observable systems. Moreover, we give a generalization of the result obtained in [D. Boutat, G. Zheng, J.P. Barbot, Observer error linearization multi-output depending, in: Proc. of IEEE CDC 06, 2006] and [G. Zheng, D. Boutat, J.P. Barbot, Single output-dependent observability normal form, SIAM Journal on Control and Optimization 46 (6) (2007)]. And some examples are given in order to illuminate our thinking.  相似文献   
67.
The effect of conductivity variation as a proposed method for the investigation of photoconductive switching properties of split ring resonators (SRRs) is simulated. Three different systems that are applicable under certain fabrication and/or optical excitation conditions are described. The simulated transmission spectrum indicates that for a large range of dark conductivity values, complete switching of the SRR resonance is possible. One of the simulated systems, involving split ring resonators on Si substrate, was fabricated and characterized. The transmission spectrum of that system was measured, with the Si in its high-resistivity state, and a −60 dB dip between 108 and 115 GHz, due to SRRs magnetic resonance, was observed.  相似文献   
68.
Summary For a commutative cancellative semigroup S, we define the rank of S intrinsically. This definition implies that the rank of S equals the usual rank of its group of quotients. We also characterize the rank in terms of embeddability into a rational vector space of the greatest power cancellative image of S.  相似文献   
69.

We show the uniqueness of left invariant symplectic structures on the affine Lie group under the adjoint action of , by giving an explicit formula of the Pfaffian of the skew symmetric matrix naturally associated with , and also by giving an unexpected identity on it which relates two left invariant symplectic structures. As an application of this result, we classify maximum rank left invariant Poisson structures on the simple Lie groups and . This result is a generalization of Stolin's classification of constant solutions of the classical Yang-Baxter equation for and .

  相似文献   

70.
We define orthodox super rpp semigroups and study their semilattice decompositions. Standard representation theorem of orthodox super rpp semigroups whose sub-band of idempotents is in the varieties of bands described by an identity with at most three variables are obtained.  相似文献   
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