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51.
A. S. Oliinyk 《Mathematical Notes》1998,63(2):215-224
It is established that the subset of freek-generated subsemigroups of the semigroup of all automaton transformations over a finite alphabet is a second category set
(in the sense of the Baire category approach) in the set of allk-generated subsemigroups. A continuum series of pairs of automaton transformations each of which generates a free semigroup
of rank two is indicated. A criterion is established for this semigroup to be a finite-automaton group.
Translated fromMatematicheskie Zametki, Vol. 63, No. 2, pp. 248–259, February, 1998.
The author wishes to express his deep gratitude to Professor V. I. Sushchans'kii for permanent help and attention to the research.
This research was partially supported by the ISSEP under grant No. GSU 051341. 相似文献
52.
The extension of two axioms due to Cook and Fischer to the category CAP of convergence approach spaces leads to the study of non-Archimedean approach spaces as well as two versions of regularity appropriate to CAP and related categories. 相似文献
53.
This paper presents a translation of a theorem of Cartan into an equivariant setting. This work is largely based on the study
of the homotopical algebra in the sense of Quillen of the category of simplicial objects over the category of rationalO
g-vector spaces. The application is a solution to the equivariant commutative cochain problem. This solution is slightly better
than the solution obtained earlier by Triantafillou in that the transformation groupG need not be finite. 相似文献
54.
定义了汉语的分段语法,并根据自然语言的分段循环结构,提出了汉语的分段循环分析策略.它的基本思想是确定语言的一组基本范畴,其相应的句法规则段及其之间的优先关系,对于每一个句法规则段,分别依次采用改进的Kilbury算法、它的优点在于分析过程中的项目集比较小,而且避免了无用分析树的产生,从而大大提高了分析效率. 相似文献
55.
Fusion Operators and Cocycloids in Monoidal Categories 总被引:1,自引:0,他引:1
Ross Street 《Applied Categorical Structures》1998,6(2):177-191
The Yang–Baxter equation has been studied extensively in the context of monoidal categories. The fusion equation, which appears to be the Yang–Baxter equation with a term missing, has been studied mainly in the context of Hilbert spaces. This paper endeavours to place the fusion equation in an appropriate categorical setting. Tricocycloids are defined; they are new mathematical structures closely related to Hopf algebras. 相似文献
56.
R. W. Kieboom 《Applied Categorical Structures》1997,5(2):131-142
It is well known that the concept of monomorphism in a category can be defined using an appropriate pullback diagram. In the homotopy category of TOP pullbacks do not generally exist. This motivated Michael Mather to introduce another notion of homotopy pullback which does exist. The aim of this paper is to investigate the modified notion of homotopy monomorphism obtained by applying the pullback characterization using Mather's homotopy pullback. The main result of Section 1 shows that these modified homotopy monomorphisms are exactly those homotopy monomorphisms (in the usual sense) which are homotopy pullback stable, hence the terminology “stable” homotopy monomorphism. We also link these stable homotopy monomorphisms to monomorphisms and products in the track homotopy category over a fixed space. In Section 2 we answer the question: when is a (weak) fibration also a stable homotopy monomorphism? In the final section it is shown that the class of (weak) fibrations with this additional property coincides with the class of “double” (weak) fibrations. The double (weak) covering homotopy property being introduced here is a stronger version of the (W) CHP in which the final maps of the homotopies involved play the same role as the initial maps. 相似文献
57.
具有广义分解态射的广义(i,…,j)逆 总被引:1,自引:0,他引:1
本文研究范畴中态射的广义(i,…,j)逆,利用态射广义分解的性质给出了态射广义(i,…,j)逆存在的一些充要条件,导出了态射的广义Moore-Penrose逆的表达式,推广了态射(i,…,j)逆的相应结果. 相似文献
58.
59.
We apply ideas from commutative algebra, and Morita theory to algebraic topology using ring spectra. This allows us to prove new duality results in algebra and topology, and to view (1) Poincaré duality for manifolds, (2) Gorenstein duality for commutative rings, (3) Benson–Carlson duality for cohomology rings of finite groups, (4) Poincaré duality for groups and (5) Gross–Hopkins duality in chromatic stable homotopy theory as examples of a single phenomenon. 相似文献
60.
《Journal of Pure and Applied Algebra》2023,227(4):107244
In this paper, we introduce the notion of G-liftable ideals, which extends the liftable ideas defined by Assem and Le Meur. We characterize the G-liftable ideals and construct the Galois G-coverings of quotients of categories associated to the G-liftable ideals. In particular, we study the behavior of G-liftable admissible ideals under Galois G-coverings. Furthermore, we show that the ideals generated by finite dimensional projective modules over a locally bounded linear categories are admissible G-liftable ideals. As an application, we provide a reduction technique for dealing with the existence of Serre functors in the stable categories of Gorenstein projective objects. 相似文献