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901.
A model is proposed to generate solutions for container selection, for the allocation of cargo to containers, and for cargo orientation within a container. The model is in the form of a mixed integer program with the objective of minimizing the total shipping cost. The practical requirements of loading priority and weight distribution along the main dimension of the container are incorporated into the model. A heuristic solution strategy is proposed and used to control the computation time by pre-setting the search increments. Three case examples are presented. The first and third examples show that the proposed model can produce a better solution than the manual schedulers. The second example is taken from the literature and is compared with the solution generated by the proposed model, demonstrating that the practical considerations incorporated into the model do not necessarily lead to increased shipping costs. 相似文献
902.
903.
An abnormal spin-spin coupling of vinylic-allylic protons generated by a constraint of configuration
In a system where a rigid or frozen conformation constrains an allylic proton to orient nearly perpendicular to the plane of the olefinic bond, the allylic spin coupling may become comparable to, or greater than, the vicinal spin coupling. This anomalous situation is demonstrated in three series of compounds: the adducts of diazoalkanes to 1,2-diazepines, 4-piperidinocycloalk-2-en-1-one oximes and heterobicyclo[3,2,0]hept-3,6-dienes, where the NMR spectra have been well established by decoupling experiments. 相似文献
904.
Experimental evidence is presented that moving Bloch-walls decrease the flow stress of nickel single crystals. Via their strain fields, Block-walls interact with dislocations. 相似文献
905.
J. W. Schneider H. Keller W. Odermatt B. Pümpin I. M. Savić H. Simmler S. A. Dodds T. L. Estle R. C. Duvarney K. Chow R. Kadono R. F. Kiefl Q. Li T. M. Riseman H. Zhou R. L. Lichti C. Schwab 《Hyperfine Interactions》1991,64(1-4):543-549
Datailed muon level-crossing resonance measurements of Mu1 and Mu11 centres in single crystals of CuCl are presented. The hyperfine and nuclear hyperfine parameters of the closest two shells
of nuclei are remarkably similar for the two centres, indicating that both are located at the same tetrahedral interstitial
site with four Cu nearest neighbours and six Cl next-nearest neighbours. About 30% of the total unpaired-electron spin density
is located on the muon, about 60% on the four nearest neighbours and the rest on the six next-nearest neighbours, with nothing
observable for any other shell. 相似文献
906.
T. R. Chow 《Mathematische Annalen》1970,188(4):285-303
907.
Summary We prove the existence and regularity of solutions to stochastic partial differential equations of parabolic Itô type in Hölder spaces under the usual sublinear growth and local Lipschitz conditions. Some examples are given to which our main theorems apply.The work of the first author was supported in part by the NSF grant DMS-91-01360 相似文献
908.
Germanium is extracted onto polyurethane foam as molybdogermanate, and determined by X-ray fluorescence spectrometry in the dried foam. The extraction is effective between pH 0.5 and 3.7 and as little as 7 μg of germanium can be detected in 100 ml of aqueous solution. 相似文献
909.
Tahsin J. Chow 《中国化学会会志》1996,43(1):101-107
The titled compounds are synthesized through multi-step sequences involving consecutive [n4s + n2s] cycloadditions of norbornadiene with two units of chlorinated cyclopentadiene. A dyotropic double hydrogen migration was observed between two closely located double bonds during the process of aromatization of a cyclohexadiene moiety. A hydroxyl group is introduced onto either of the two methylene bridges in order to provide products suitable for solvolytic analyses. 相似文献
910.
A.?Jafarpour E.?Chow C.M.?Reinke J.?Huang A.?AdibiEmail author A.?Grot L.W.?Mirkarimi G.?Girolami R.K.?Lee Y.?Xu 《Applied physics. B, Lasers and optics》2004,79(4):409-414
For the first time, we experimentally demonstrate ultra-low-loss guiding in bi-periodic photonic crystal waveguides over a large bandwidth of more than 60 nm. In such bi-periodic waveguides, we achieve a propagation loss very similar to that of a dielectric ridge waveguide, which indicates that the dominant loss mechanism in these bi-periodic waveguides is due to fabrication imperfections. PACS 42.70.Qs; 42.79.Gn 相似文献