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151.
In this paper, we state and study the problem of selecting a product mix and a dispatching rule for a jobshop system to maximize its revenue rate over an infinite planning horizon. 相似文献
152.
We prove that the inscribed and circumscribed ball conditions, commonly used in finite element analysis, are equivalent in any dimension. 相似文献
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157.
Ivan Poto?ňák Michal Dunaj-Jur?o Du?an Miklo? Lothar J?ger 《Monatshefte für Chemie / Chemical Monthly》2001,22(6):315-327
The structure of the new compound [Cu(bpy)2N(CN)2]C(CN)3 (6) is compared with thestructures of six copper(II) coordination compounds with phenanthroline or bipyridine ligands and N-donor pseudohalide anions: [Cu(phen)2NCS]C(CN)3 (1), [Cu(bpy)2NCS]C(CN)3 (2), [Cu(phen)2NCS]ONC(CN)2 (3), [Cu(phen)2N(CN)2]C(CN)3 (4), [Cu(bpy)2C(CN)3]C(CN)3 (5), and [Cu(bpy)2NCO]C(CN)3 (7). The Cu(II) atoms in all above compounds are five-coordinated with an N-donor atom of the pseudohalide anion located in the equatorial plane of a deformed trigonal bipyramid. The shape of the coordination polyhedra and the degree of trigonal bipyramidal distortion towards a tetragonal pyramid are discussed and described using one electronic and several structural criteria which are discussed and compared. 相似文献
158.
A Heuristic for Moment-Matching Scenario Generation 总被引:1,自引:0,他引:1
Kjetil Høyland Michal Kaut Stein W. Wallace 《Computational Optimization and Applications》2003,24(2-3):169-185
In stochastic programming models we always face the problem of how to represent the random variables. This is particularly difficult with multidimensional distributions. We present an algorithm that produces a discrete joint distribution consistent with specified values of the first four marginal moments and correlations. The joint distribution is constructed by decomposing the multivariate problem into univariate ones, and using an iterative procedure that combines simulation, Cholesky decomposition and various transformations to achieve the correct correlations without changing the marginal moments.With the algorithm, we can generate 1000 one-period scenarios for 12 random variables in 16 seconds, and for 20 random variables in 48 seconds, on a Pentium III machine. 相似文献
159.
A direct tetraalkylation of thiacalix[4]arenes using procedures well established in ‘classical’ calixarene chemistry usually gives the 1,3-alternate conformers as the main product (n-PrI/K2CO3/acetone) while the cone conformers are obtained only in very poor yields (n-PrI/NaH/DMF). Surprisingly, the so far almost inaccessible cone conformers can be prepared in high yields using the two-step procedure: dialkylation-dialkylation, opening the way for their further utilisation in supramolecular chemistry. 相似文献
160.
Michal Fećkan 《Applications of Mathematics》1997,42(5):369-393
Ordinary differential inclusions depending on small parameters are considered such that the unperturbed inclusions are ordinary differential equations possessing manifolds of periodic solutions. Sufficient conditions are determined for the persistence of some of these periodic solutions after multivalued perturbations. Applications are given to dry friction problems. 相似文献