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171.
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Francesco Ciraulo 《Mathematical Logic Quarterly》2008,54(1):35-48
This paper provides a constructive topological semantics for non‐deducibility of a first order intuitionistic formula. Formal topology theory, in particular the recently introduced notion of a binary positivity predicate, and co‐induction are two needful tools. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
174.
Let q be a power of a prime and n a positive integer. Let P(q) be a parabolic subgroup of the finite general linear group GL
n
(q). We show that the number of P(q)-conjugacy classes in GL
n
(q) is, as a function of q, a polynomial in q with integer coefficients. This answers a question of Alperin in (Commun. Algebra 34(3): 889–891, 2006) 相似文献
175.
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177.
M. S. Antonious M. N. Ramsis A. O. Youssef 《Monatshefte für Chemie / Chemical Monthly》1996,127(1):15-27
Summary The kinetics of the crystallization of barium chromate have been studied conductometrically at 298 K for both spontaneous and seeded growth systems. The rate of growth follows a quadratic dependence upon the relative supersaturation which suggests a surface-controlled growth mechanism. This rate equation holds fairly well for the various supersaturation and solid/solution ratios used. The presence of seeds in the solution appears to accelerate the growth rate. Analysis of the calculated induction times in unseeded systems corroborates the surface-controlled growth mechanism. The effect of some additives on the kinetics of growth has also been studied. The retarding effect of these inhibitors is interpreted in terms of adsorption of inhibitor ions at the active crystal growth sites.Dedicated to the memory of ProfessorE. N. Rizkalla who passed away on November 29, 1993 相似文献
178.
In this paper, the eigenvalue problem of a multilayer dielectric waveguide consisting of arbitrary number of layers is solved by the microwave network method. A general program with the function of computer graphics has been developed for analyzing the dispersion characteristics and the electromagnetic field distributions of an N layer dielectric waveguide. As examples of practical applications of the program, first, the dispersions and field patterns for the planar waveguides with refractive index of parabolic and exponential profiles are analyzed. Secondly, the procedure of mode conversion and mode separation in dielectric branching waveguides is vividly demonstrated through analyzing the field distributions of asymmetric multilayer dielectric structures and the general rules of mode conversion are discussed. The examples show that the present method possesses the advantages of versatility, rapidity, simplicity and accuracy. 相似文献
179.
A computational algorithm for optimal control problems with control and terminal inequality constraints involving first boundary-value problems of parabolic type is presented. The convergence properties are also studied.This work, which was partly supported by the Australian Research Grants Committee, was done during the period when Z. S. Wu was an Honorary Visiting Fellow in the School of Mathematics at the University of New South Wales, Australia. 相似文献
180.
Let be a non-Archimedean local field (of characteristic or ) with finite residue field of characteristic . An irreducible smooth representation of the Weil group of is called essentially tame if its restriction to wild inertia is a sum of characters. The set of isomorphism classes of irreducible, essentially tame representations of dimension is denoted . The Langlands correspondence induces a bijection of with a certain set of irreducible supercuspidal representations of . We consider the set of isomorphism classes of certain pairs , called ``admissible', consisting of a tamely ramified field extension of degree and a quasicharacter of . There is an obvious bijection of with . Using the classification of supercuspidal representations and tame lifting, we construct directly a canonical bijection of with , generalizing and simplifying a construction of Howe (1977). Together, these maps give a canonical bijection of with . We show that one obtains the Langlands correspondence by composing the map with a permutation of of the form , where is a tamely ramified character of depending on . This answers a question of Moy (1986). We calculate the character in the case where is totally ramified of odd degree.