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101.
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103.
J. Žofka 《Czechoslovak Journal of Physics》1970,20(8):926-938
A review of the Hartree-Fock (HF) self-consistent method is presented as used in nuclear theory. After deriving the fundamental HF equations the two-particle potentials for HF calculations are shown and the particular HF methods described. Furthermore the results of some papers on HF methods are reproduced and discussed. 相似文献
104.
I. S. Žiguleva 《Colloid and polymer science》1977,255(8):813-813
Ohne Zusammenfassung 相似文献
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106.
Closely spaced angular distributions have been measured for the reaction between Eα = 17.39 and 20.5 MeV in a search for 8+ strength in 16O. No evidence of 8+ strength is found, but evidence is found for a narrow 7? resonance at 21.52 MeV excitation. 相似文献
107.
Boštjan Žekš 《Molecular Crystals and Liquid Crystals》2013,570(1-3):259-270
The biquadratic coupling between the tilt and polarization is added to the usual bilinear coupling in the Landau free energy density expansion describing the SmA - SmC* transition. The effect on the temperature dependence of the tilt, spontaneous polarization and the pitch of the helix is studied. The results agree qualitatively with measured data. 相似文献
108.
We consider the so-called Ladyzhenskaya model of incompressible fluid, with an additional artificial smoothing term ?Δ3. We establish the global existence, uniqueness, and regularity of solutions. Finally, we show that there exists an exponential attractor, whose dimension we estimate in terms of the relevant physical quantities, independently of ? > 0. 相似文献
109.
Computing transitive closure of bipolar weighted digraphs 总被引:1,自引:0,他引:1
We define a bipolar weighted digraph as a weighted digraph together with the sign function on the arcs such that the weight of each arc lies between 0 and 1, and no two parallel arcs have the same sign. Bipolar weighted digraphs are utilized to model so-called fuzzy cognitive maps, which are used in science, engineering, and the social sciences to represent the causal structure of a body of knowledge. It has been noted in the literature that a transitive closure of a bipolar weighted digraph contains useful new information for the fuzzy cognitive map it models.In this paper we ask two questions: what is a sensible and useful definition of transitive closure of a bipolar weighted digraph, and how do we compute it? We give two answers to each of these questions, that is, we present two distinct models. First, we give a review of the fuzzy digraph model, which has been, in a different form and less rigorously, studied previously in the fuzzy systems literature. Second, we carefully develop a probabilistic model, which is related to the notion of network reliability.This paper is intended for a mathematical audience. 相似文献
110.
A hybrid global optimization algorithm is proposed aimed at the class of objective functions with properties typical of the problems of non-linear least squares regression. Three components of hybridization are considered: simplicial partition of the feasible region, indicating and excluding vicinities of the main local minimizers from global search, and computing the indicated local minima by means of an efficient local descent algorithm. The performance of the algorithm is tested using a collection of non-linear least squares problems evaluated by other authors as difficult global optimization problems. 相似文献