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91.
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John P. Matthews 《The Journal of the Operational Research Society》1988,39(12):1155-1161
The economic lot-scheduling problem for the single-machine, n-item scheduling problem has received attention in a number of journals. One approach is to define a sequence (called the fundamental cycle) in which every item is made at least once, and then to determine the length of production runs consistent with the aggregate inventory level which will maximize the length of the cycle duration. The assumption that production is switched from one item to the next only when the inventory level of the latter reaches zero is often used in heuristic solutions to these models. This paper illustrates the conditions in which the ‘zero-switch’ rule is a necessary condition at the optimal solution for situations in which demand is continuous and production capacity equals aggregate demand. 相似文献
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95.
F. Dibianca R.L. Eisner W. Fickinger J.A. Malko D. Matthews J. OReilly J.F. Owens D.K. Robinson S.U. Chung S.D. Protopopescu 《Physics letters. [Part B]》1976,63(4):461-465
Data are presented on the reactions π+n → ?0+X and , respectively. Comparisons are made with related reactions at higher energies. 相似文献
96.
The negative ion mass spectra of highly fluorinated molecules with varying functionality are discussed. Attempts to obtain negative molecular ions where no positive molecular ion was observed met with little success. An interesting structural correlation for fluorinated ethers was developed based upon the observation of the abundant perfluoro alkoxide anions, CF3O? and CF3(CF2)2O?, in the negative ion mass spectrum. 相似文献
97.
Matthews JR Goldoni F Schenning AP Meijer EW 《Chemical communications (Cambridge, England)》2005,(44):5503-5505
The non-aggregating nature of a water-soluble pi-conjugated polythiophene has been characterised by concentration independent thermal denaturing. 相似文献
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D. M. Fatheree G. L. Deeg D. B. Matthews J. G. Russell 《Magnetic resonance in chemistry : MRC》1982,18(2):92-97
The vicinal proton coupling constants were obtained for some 6-membered ring unsaturated heterocyclic compounds. The R values and ring dihedral angles were determined and found to be consistent with half-chair conformations. Relative to saturated heterocyclic compounds, the effect of the sulfur atom on ring puckering was attenuated. However, an increase in ring puckering resulted from the sulfone group and was attributed to torsional energy. 相似文献
100.