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131.
Mark Kambites 《Semigroup Forum》2008,76(2):204-216
We study the relationship between the loop problem of a semigroup, and that of a Rees matrix construction (with or without
zero) over the semigroup. This allows us to characterize exactly those completely zero-simple semigroups for which the loop
problem is context-free. We also establish some results concerning loop problems for subsemigroups and Rees quotients. 相似文献
132.
Takeshi Torii 《Topology and its Applications》2005,150(1-3):33-57
We have a ring homomorphism Θ from the cohomology of the extended Morava stabilizer group Gn with coefficients in F[w±1] to the cohomology of Gn+1 with coefficients in the graded field F((un))[u±1]. In this note we study the behavior of Θ on H1. Then it is shown that Θ is injective on H1 for n1 and for all primes p. 相似文献
133.
G. Richomme 《Discrete Applied Mathematics》2007,155(15):2001-2016
A challenging problem is to find an algorithm to decide whether a morphism is k-power-free. When k?3, we provide such an algorithm for uniform morphisms showing that in such a case, contrarily to the general case, there exist finite test-sets for k-power-freeness. 相似文献
134.
Tejinder S. Neelon 《Journal of Mathematical Analysis and Applications》2004,299(1):61-71
The regularity, in the sense of ultradifferentiability, of real functions of two variables is determined in terms of the regularity of their restrictions to a given family of smooth plane curves. The special case of line segments reduces to the main result in [Proc. Amer. Math. Soc. 127 (1999) 2099-2104]. As a consequence, the Bochnak-Siciak theorem on real analyticity is obtained. A formal analog of one of the results provides a generalization of the two-variable case of the Abhyankar and Moh [J. Reine Angew. Math. 241 (1970) 27-33] theorem. 相似文献
135.
介绍了荧光淬灭法溶解氧测定仪的工作原理,探讨了该类仪器计量特性和校准方法,提出了校准项目和技术指标,零值误差(≤0.10 mg/L)、溶解氧浓度示值误差(±0.50 mg/L)、重复性(≤0.20 mg/L)、响应时间(≤60 s)。用该校准方法对某些荧光淬灭法溶解氧测定仪进行了校准,证明该法是可行的。 相似文献
136.
We explore a connection between different ways of representing information in computer science. We show that relational databases,
modules, algebraic specifications and constraint systems all satisfy the same ten axioms. A commutative semigroup together
with a lattice satisfying these axioms is then called an “information algebra”. We show that any compact consequence operator
satisfying the interpolation and the deduction property induces an information algebra. Conversely, each finitary information
algebra can be obtained from a consequence operator in this way. Finally we show that arbitrary (not necessarily finitary)
information algebras can be represented as some kind of abstract relational database called a tuple system.
Mathematics Subject Classification (2000): Primary 03B22; Secondary 03G15 03G25 08A70 68Q99 94A99 03C950 相似文献
137.
138.
Michael Fuchs 《Journal of Number Theory》2003,101(1):105-130
About 40 years ago, Szüsz proved an extension of the well-known Gauss-Kuzmin theorem. This result played a crucial role in several subsequent papers (for instance, papers due to Szüsz, Philipp, and the author). In this note, we provide an analogue in the field of formal Laurent series and outline applications to the metric theory of continued fractions and to the metric theory of diophantine approximation. 相似文献
139.
Martin Große-Rhode 《Applied Categorical Structures》1998,6(4):403-426
Algebra replacement systems are introduced as formal models of state dependent and state transforming systems. The first part of an institution of algebra replacement systems is developed, that is, a model theoretic and logical framework that can be used to describe and reason about such systems. The usual operational understanding of a replacement system as a labeled transition system is then considered as one particular model in the model category. Under appropriate conditions such a constructed replacement system is initial. 相似文献
140.
提出广义模糊传递性和形式三传递阵的概念,给出已有模糊传递定义的一种统一形式,确定所有的三传递模糊矩阵,初步理清它们的层次和部分等价关系,为模糊矩阵传递性进一步研究和应用提供背景和方法。 相似文献