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991.
V. A. Artamonov 《Journal of Mathematical Sciences》1991,57(2):2959-3009
A survey of the development of the theory of universal algebras in the years 1976–1988. Such basic directions of development of this theory as classes of universal algebras (varieties, quasivarieties, etc.), Mal'tsev conditions, congruences, sheaves, homomorphisms, subalgebras, products of algebras, clones of operations, completeness, systems of equations in algeberas, and connections with computer mathematics show up in it. Considerable attention is given to concrete classes of algebras (p-algebras, BCK-algebras, unary algebras, etc.).Translated from Itogi Nauki i Tekhniki, Seriya Algebra, Topologiya, Geometriya, Vol. 27, pp. 45–124, 1989. 相似文献
992.
The spin-1 Ising model, which is equivalent to the three-component lattice gas model, is used to study wetting transitions in three-component surfactant systems consisting of an oil, water, and a nonionic surfactant. Phase equilibria, interfacial profiles, and interfacial tensions for three-phase equilibrium are determined in mean field approximation, for a wide range of temperature and interaction parameters. Surfactant interaction parameters are found to strongly influence interfacial tensions, reducing them in some cases to ultralow values. Interfacial tensions are used to determine whether the middle phase, rich in surfactant, wets or does not wet the interface between the oil-rich and water-rich phases. By varying temperature and interaction parameters, a wetting transition is located and found to be of the first order. Comparison is made with recent experimental results on wetting transitions in ternary surfactant systems.This paper is dedicated to J. K. Percus in honor of his 65th birthday. 相似文献
993.
C Premkumar Yesudian 《Pramana》1989,33(6):651-657
An extended technicolour grand unification model based on the gauge groupE
6×SU(7) extended technicolour is presented. The symmetry-breaking based on extended technicolour theory is discussed. It is
shown that the existing phenomenology is well explained by the model. The strangeness changing neutral currents may not be
a problem with this model. 相似文献
994.
M. B. Wright 《The Journal of the Operational Research Society》1989,40(2):187-192
This paper addresses a problem common to all railway networks. Given a fixed train timetable and locomotives (or other forms of traction) of various types, each train must be allocated a locomotive. This paper examines the use of stochastic algorithms for such a problem. Two types of algorithm are used—a simple ‘local improvement’ method, performed successively from randomly chosen starting points, and a ‘simulated annealing’ approach. Both are found to give considerably better results than a deterministic method in current use, and the annealing approach is probably the better stochastic method. 相似文献
995.
996.
997.
998.
E. A. Bailov N. Temirgaliev 《Computational Mathematics and Mathematical Physics》2006,46(9):1515-1525
Sharp estimates (in the power scale) are obtained for the discretization error in the solutions to Poisson’s equation whose right-hand side belongs to a Korobov class. Compared to the well-known Korobov estimate, the order is almost doubled and has an ultimate value in the power scale. 相似文献
999.
A. L. Chistov 《Journal of Mathematical Sciences》2006,138(3):5733-5752
Consider a projective algebraic variety W which is an irreducible component of the set of all common zeros of a family of
homogeneous polynomials of degrees less than d in n + 1 variables over a field of zero characteristic. Consider a dominant
rational morphism from W to W′ given by homogeneous polynomials of degree d′. We suggest algorithms for constructing objects
in general position related to this morphism. They generalize some algorithms from the first part of the paper to the case
dim W > dim W′. These algorithms are deterministic and polynomial in (dd′)n and the size of the input. Bibliography: 12 titles.
__________
Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 325, 2005, pp. 181–224. 相似文献
1000.
D. C. Oliveira Y. Messaddeq K. Dahmouche S. J. L. Ribeiro R. R. Gonçalves A. Vesperini D. Gindre J.-M. Nunzi 《Journal of Sol-Gel Science and Technology》2006,40(2-3):359-363
Organic-inorganic hybrid materials were prepared from an ureasil precursor (ureapropyltriethoxysilane designated as UPTES)
and acrylic acid modified zirconium (IV) n-propoxide. Thin films containing rhodamine 6G (Rh6G) were prepared by spin-coating on glass substrates with different Zr:Si molar ratios (Zr:Si = 75:25, 50:50 and 25:75). Refractive
index, thickness, number of propagating modes and attenuation coefficient were measured at 543.5, 632.8 and 1550 nm wavelengths
by the prism coupling technique. Distributed feedback (DFB) laser effect was observed and studied as a function of films thickness
and refractive index. 相似文献