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891.
S. E. Bogushevich V. N. Makatun A. K. Potapovich I. I. Ugolev 《Journal of Applied Spectroscopy》1991,55(4):1016-1020
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 55, No. 4, pp. 613–618, October, 1991. 相似文献
892.
The present paper is aimed to display the performance of the Fourier-Galerkin technique developed earlier by the authors for numerical treatment of localized solutions in
2(-∞, ∞) for higher-order equations. The solitary-wave solution of the Kortweg-de Vries fifth order equation is obtained numerically and compared with approximate results of other authors. 相似文献
893.
K. -H. Ulbrich 《manuscripta mathematica》1987,59(4):391-397
Let A be a finite Hopf algebra over a commutative ring k. We show a one-to-one correspondence between the A-Galois extensions of k and certain functors from the category of A-comodules to the category of k-modules. 相似文献
894.
The palladium-catalyzed α-arylation of ketones on solid support is described. Using modified Buchwald-Hartwig reaction conditions, the coupling of immobilized 4-bromobenzamide with various aromatic, heteroaromatic, and aliphatic ketones was investigated. Subsequent cleavage from the resin provided the desired α-aryl ketones almost in moderate to high yields and good to excellent purities. The scope and limitations of this protocol will be discussed. 相似文献
895.
A Hybrid Multiobjective Evolutionary Algorithm for Solving Vehicle Routing Problem with Time Windows 总被引:2,自引:0,他引:2
Vehicle routing problem with time windows (VRPTW) involves the routing of a set of vehicles with limited capacity from a central
depot to a set of geographically dispersed customers with known demands and predefined time windows. The problem is solved
by optimizing routes for the vehicles so as to meet all given constraints as well as to minimize the objectives of traveling
distance and number of vehicles. This paper proposes a hybrid multiobjective evolutionary algorithm (HMOEA) that incorporates
various heuristics for local exploitation in the evolutionary search and the concept of Pareto's optimality for solving multiobjective
optimization in VRPTW. The proposed HMOEA is featured with specialized genetic operators and variable-length chromosome representation
to accommodate the sequence-oriented optimization in VRPTW. Unlike existing VRPTW approaches that often aggregate multiple
criteria and constraints into a compromise function, the proposed HMOEA optimizes all routing constraints and objectives simultaneously,
which improves the routing solutions in many aspects, such as lower routing cost, wider scattering area and better convergence
trace. The HMOEA is applied to solve the benchmark Solomon's 56 VRPTW 100-customer instances, which yields 20 routing solutions
better than or competitive as compared to the best solutions published in literature. 相似文献
896.
897.
898.
T. Riesterer J. G. Bednorz K. A. Müller B. Reihl 《Applied Physics A: Materials Science & Processing》1987,44(1):81-82
We have measured ultraviolet and inverse-photoemission spectra of the novel superconductor Sr02La1.8CuO4. Our results compare favorably with recent band-structure calculations for La2CuO4.A full account of this work will be published elsewhere [1] 相似文献
899.
900.
Theoretical investigations and the results of computer modeling of the optical, thermophysical, and thermochemical processes during laser interaction with ocular tissues are reviewed in this paper. Physical-mathematical models and results of numerical simulation of the processes are presented. The computer modeling was applied for investigations of laser heating and coagulation of ocular tissues for treatment of retina diseases and intraocular tumors, cyclophotocoagulation of the ciliary body for treatment of glaucoma, and laser thermal keratoplasty of the cornea. The influence of radiation parameters on the selectivity of laser coagulation of laminated ocular tissues is considered. The results obtained are of essential interest for laser applications in ophthalmology and can be used for investigation of heating and coagulation of tissues in different fields of laser medicine. 相似文献