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41.
《Indagationes Mathematicae》2022,33(6):1312-1325
The Central Sets Theorem was introduced by H. Furstenberg and then afterwards several mathematicians have provided various versions and extensions of this theorem. All of these theorems deal with central sets, and its origin from the algebra of Stone–?ech compactification of arbitrary semigroup, say . It can be proved that every closed subsemigroup of is generated by a filter. We will show that, under some restrictions, one can derive the Central Sets Theorem for any closed subsemigroup of . We will derive this theorem using the corresponding filter and its algebra. Later we will also deal with how the notions of largeness along filters are preserved under some well behaved homomorphisms and give some consequences. 相似文献
42.
Stefano Serra-Capizzano Per Sundqvist 《Journal of Computational and Applied Mathematics》2008,219(2):518
Given an approximating class of sequences {{Bn,m}n}m for {An}n, we prove that (X+ being the pseudo-inverse of Moore–Penrose) is an approximating class of sequences for , where {An}n is a sparsely vanishing sequence of matrices An of size dn with dk>dq for k>q,k,qN. As a consequence, we extend distributional spectral results on the algebra generated by Toeplitz sequences, by including the (pseudo) inversion operation, in the case where the sequences that are (pseudo) inverted are distributed as sparsely vanishing symbols. Applications to preconditioning and a potential use in image/signal restoration problems are presented. 相似文献
43.
The ideas of equivalence and variable are two of the most fundamental concepts in algebra. Most studies of students’ understanding of these concepts have posited a gap between the students’ conceptions and the institutional meanings for the symbols. In contrast, this study develops a theoretical framework for describing the ways undergraduate students use personal meanings for symbols as they appropriate institutional meanings. To do this, we introduce the idea of semiotic systems as a framework for understanding the ways students use collections of signs to engage in mathematical activity and how the students use these signs in meaningful ways. The analysis of students’ work during task-based interviews suggests that this framework allows us to identify the ways in which seemingly idiosyncratic uses of the symbols are evidence of meaning-making and, in many cases, how the symbol use enables the student to engage productively in the mathematical activity. 相似文献
44.
Left supersymmetric Structures on Lie Superalgebras 总被引:2,自引:0,他引:2
Wang Xiandong 《东北数学》1999,(2)
§1.IntroductionRecently,thestudyofleft-symmetricalgebrasandleft-symmetricstructuresonLiealgebrashasbecomeaninterestingsubject... 相似文献
45.
It was shown that N=1 super-symmetry algebra can be constructed in de Sitter space (Pahlavan et al. in Phys Lett. B 627:217–223, 2005), through calculation of charge conjugation in the ambient space notation (Moradi et al. in Phys. Lett. B 613:74, 2005; Phys. Lett. B 658:284, 2008). Calculation of N=2 super-symmetry algebra constitutes the main frame of this paper. N=2 super-symmetry algebra was presented in Pilch et al. (Commun. Math. Phys. 98:105, 1985). In this paper, we obtain an alternative N=2 super-symmetry algebra. 相似文献
46.
Algebras of fuzzy sets 总被引:2,自引:0,他引:2
In this paper we investigate two kinds of algebras of fuzzy sets, which are obtained by using Zadeh's extension principle. We give conditions under which a homomorphism between two algebras induces a homomorphism between corresponding algebras of fuzzy sets. We prove that if the structure of truth values is a complete residuated lattice, the induced algebra of a subalgebra of an algebra can be embedded into the induced algebra of fuzzy sets of . For direct products we give conditions under which the direct product of algebras of fuzzy sets could be embedded into the algebra of fuzzy sets of the direct product. In the case of homomorphisms and direct products, the two kinds of algebras of fuzzy sets behave in different ways. 相似文献
47.
48.
在效应代数中引入模糊滤子和模糊理想的概念,讨论了它们的性质;引入并研究了强模糊滤子;在全序效应代数中提出了一个模糊同余关系并证明了这样生成的同余类是一个全序格效应代数. 相似文献
49.
在[4]中,我们引入了Z-蕴含代数的概念,讨论了它们的一些性质.本文中,我们进一步引入Z-蕴含代数的Z-滤子,并研究它们一些有趣的结果. 相似文献
50.
《复变函数与椭圆型方程》2012,57(10):915-928
In this paper, we obtain Cauchy's integral formula on certain distinguished boundary for functions with values in a universal Clifford algebra, which is similar to the classical Cauchy's integral formula on the distinguished boundary of polycylinder for several complex variables. By using it, both the mean value theorem and the maximum modulus theorem are given. 相似文献