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61.
62.
A manual method was developed for scheduling the vehicle fleet of a contract transport undertaking. The main requirements were observance of time limits on individual calls and the ability to allocate pairs or groups of related calls to the same vehicle. These objectives were achieved by introducing an initial allocation of calls to vehicles prior to sequential routing of the calls. The allocation was based on a model relating work density (calls per unit area) to vehicle loading (calls per unit of vehicle time), and on fact-finding research on the main parameters of calling time, travelling speed and distance. This relationship was embodied in a visual scheduling aid for use by the route planners. Implementation was successful and resulted in about 15 per cent of vehicle time being made available for additional revenue-earning work without increase in fleet size. When utilized this represented an effective saving in operating costs of about 12 per cent. 相似文献
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64.
The use of the solvent shift techniques enables the position of methyl, methoxyl and aromatic protons in coumarins to be determined and should prove a valuable aid to structural elucidation in this class of compounds. 相似文献
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67.
Julia F. Knight 《Israel Journal of Mathematics》1982,42(1-2):151-161
Buechler proved that ifT satisfies certain conditions, then all resplendent models ofT are homogeneous. Here the theories whose resplendent models are all homogeneous are characterized as satisfying a pair of
conditions (weaker than Buechler’s). It follows from the characterization that if all resplendent models ofT in some uncountable power are homogeneous, then all resplendent models ofT are homogeneous.
The author thanks John Baldwin and the other participants in the 1979 and 1980 Forking Festivals for helping her to learn
some stability, and especially, Steve Buechler, whose results led directly to the results of this paper. Research partially
supported by the National Science Foundation under Grant MCS78-02224. 相似文献
68.
Citral (I) is cyclized by UV irradiation1 to 2-isopropenyl-5-methylcyclopentane-carboxaldehyde (II), containing the carbon skeleton of the monoterpenes of ants and catmint. 1,6,6-Trimethylbicyclo[2,1,1]hexane-2-carboxaldehyde (XII, R = H), produced in lesser amount at the same time, was synthesized from camphor. The two photocitrals may, perhaps, come from a common intermediate containing the cyclopentane ring. 相似文献
69.
D. J. E. Knight 《Optical and Quantum Electronics》1969,1(4):161-164
Wavelength and frequency data for far-infrared c.w. gas laser lines have been scanned using a computer for chains of harmonic coincidences suitable for transferring frequency measurements from the submillimetre to the 10m wavelength region. A table of selected possibilities using up to three lasers in sequence is presented showing the calculated beat frequencies. 相似文献
70.
Deuterium labeling studies have established that elimination of a cyclooctylammonium iodide with dimsyl anion in DMSO proceeds through an ylide intermediate while elimination with KOC(CH3)3 in DMSO involves an E2 mechanism. The effective base with KOC(CH3)3/DMSO is shown to be the alkoxide ion. 相似文献