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21.
F. F. Éfendiev 《Mathematical Notes》1992,51(2):204-207
Translated from Matematicheskie Zametki, Vol. 51, No. 2, pp. 139–143, February, 1992. 相似文献
22.
Vincent Bailliez 《Tetrahedron》2004,60(5):1079-1085
Polynitrogenated analogues of glucopyranoses were synthesised from levoglucosan. These compounds are useful intermediates for the synthesis of new aminoglycoside mimetics. 相似文献
23.
Christophe Rochais Vincent Lisowski Patrick Dallemagne Sylvain Rault 《Tetrahedron letters》2004,45(33):6353-6355
Novel arylpyrrolo- and pyrazolopyrrolizinones were prepared in three or four steps starting from aminoarylpyrrole and pyrazole carboxylates through the cyclisation of a Vilsmeier-Haack intermediate. This synthesis was enhanced by diverse N-protections of the aza-heterocycle and furnish new series with potential biological interest. 相似文献
24.
Institut des Hautes Études Scientifiques 《Publications Mathématiques de L'IHéS》2004,100(1):271-282
Sans résumé 相似文献
25.
26.
A multiparameter boundary-value problem of fresh infiltration water seepage in a drained fringe above quiescent saline water is solved in the direct statement and studied in detail. 相似文献
27.
Yu. G. Abov D. S. Denisov N. O. Elyutin S. K. Matveev Yu. I. Smirnov A. O. Éidlin F. S. Dzheparov D. V. L’vov 《Journal of Experimental and Theoretical Physics》1998,87(6):1195-1200
The asymptotic behavior of the spectra for large values of the scattering vector for the case of elastic multiple small-angle
neutron scattering (SANS) is investigated theoretically and experimentally. An expansion of the spectrum in terms of the reciprocal
of the magnitude of the momentum transfer is obtained taking account of the influence of the instrumental line. It is shown
that, to within some factor, the leading term of the expansion is identical to the differential single-scattering cross section
averaged over a statistical ensemble of particles; several subsequent terms in the expansion are calculated and the range
of applicability of the resulting expressions is determined. The asymptotic behavior of the multiple SANS spectrum is measured,
using a two-crystal neutron spectrometer, for samples of an HTSC ceramic, the alloy Fe-Ni, and Al powder. The agreement between
the experimental results and the theoretical predictions is analyzed.
Zh. éksp. Teor. Fiz. 114, 2194–2203 (December 1998) 相似文献
28.
E. D. Éidel’man 《Technical Physics》1998,43(11):1275-1279
A theory is developed for a new type of transition — a change in the ratio of the longitudinal and transverse dimensions of
a convection cell as the thickness of a liquid layer is varied. A sudden change in the ratio of the cell dimensions takes
place because of a change in the predominant mechanism for excitation of convection. The governing influence of buoyancy forces
gives way to one of thermocapillary forces, and they in turn give way to the influence of thermoelectric forces for yet thinner
layers. As the layer thickness is reduced gradually at a fixed external heating, the ratio of the dimensions will take on
the values 0.7, 0.65, and 1, respectively.
Zh. Tekh. Fiz. 68, 7–11 (November 1998) 相似文献
29.
COSEARCH: A Parallel Cooperative Metaheuristic 总被引:1,自引:0,他引:1
In order to design a well-balanced metaheuristic for robustness, we propose the COSEARCH approach which manages the cooperation
of complementary heuristic methods via an adaptive memory which contains a history of the search already done. In this paper,
we present the idiosyncrasies of the COSEARCH approach and its application for solving large scale instances of the quadratic
assignment problem (QAP). We propose an original design of the adaptive memory in order to focus on high quality regions of
the search and avoid attractive but deceptive areas. For the QAP, we have hybridized three heuristic agents of complementary
behaviours: a Tabu Search is used as the main search algorithm, a Genetic Algorithm is in charge of the diversification and
a Kick Operator is applied to intensify the search. The evaluations have been executed on large scale network of workstations
via a parallel environment which supports fault tolerance and adaptive dynamic scheduling of tasks. 相似文献
30.