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51.
FROM MANUFACTURING SCHEDULING TO SUPPLY CHAIN COORDINATION:THE CONTROL OF COMPLEXITY AND UNCERTAINTY
Peter B.LUH 《系统科学与系统工程学报(英文版)》2003,12(3):279-297
With time-based competition and rapid technology advancements, effective manufacturingscheduling and supply chain coordination are critical to quickly respond to changing marketconditions. These problems, however, are difficult in view of inherent complexity and variousuncertainties involved. Based on a series of results by the authors, decomposition and coordination byusing Lagrangian relaxation is identified in this paper as an effective way to control complexity anduncertainty.A manufacturing scheduling problem is first formulated within the job shop context withuncertain order arrivals, processing times, due dates, and part priorities as a separable optimizationproblem. A solution methodology that combines Lagrangian relaxation, stochastic dynamicprogramming, and heuristics is developed. Method improvements to effectively solve large problemsare also highlighted. To extend manufacturing scheduling within a factory to coordinate autonomicmembers across chains of suppliers, a decentralized supply chai 相似文献
52.
基于强跟踪滤波器估计的最优融合方法 总被引:5,自引:0,他引:5
在分布式雷达数据处理模式中 ,数据融合是获得较精确的目标轨迹的主要环节。为克服卡尔曼滤波器对初始值敏感、鲁棒性差和对机动目标跟踪性能差的缺陷 ,通过利用各传感器的观测数据 ,采用强跟踪滤波器对目标进行跟踪 ,以改善目标状态估计的精度。对判定源于同一目标的状态估计值 ,给出了一种估计状态线进行性组合的最优融合准则。得出了实际数据的实验结果。 相似文献
53.
Low-molecular-weight GTP-binding proteins are strong candidates for regulators of membrane traffic. In yeast, mutations in the sec4 or ypt1 genes encoding small GTP-binding proteins inhibit constitutive membrane flow at the plasma membrane or Golgi complex, respectively. It has been suggested that membrane fusion-fission events are regulated by cycling of small GTP-binding proteins between a membrane-bound and free state, but although most of these small proteins are found in both soluble and tightly membrane-bound forms, there is no direct evidence to support such cycling. In rat brain a small GTP-binding protein, rab3A, is exclusively associated with synaptic vesicles, the secretory organelles of nerve terminals. Here we use isolated nerve terminals to study the fate of rab3A during synaptic vesicle exocytosis. We find that rab3A dissociates quantitatively from the vesicle membrane after Ca2(+)-dependent exocytosis and that this dissociation is partially reversible during recovery after stimulation. These results are direct evidence for an association-dissociation cycle of a small GTP-binding protein during traffic of its host membrane. 相似文献
54.
M E MacDonald A Novelletto C Lin D Tagle G Barnes G Bates S Taylor B Allitto M Altherr R Myers 《Nature genetics》1992,1(2):99-103
Analysis of 78 Huntington's disease (HD) chromosomes with multi-allele markers revealed 26 different haplotypes, suggesting a variety of independent HD mutations. The most frequent haplotype, accounting for about one third of disease chromosomes, suggests that the disease gene is between D4S182 and D4S180. However, the paucity of an expected class of chromosomes that can be related to this major haplotype by assuming single crossovers may reflect the operation of other mechanisms in creating haplotype diversity. Some of these mechanisms sustain alternative scenarios that do not require a multiple mutational origin for HD and/or its positioning between D4S182 and D4S180. 相似文献
55.
56.
Y. G. Ma 《复旦学报(自然科学版)》2007,46(1):33-40
Progress on nuclear liquid gas phase transition (LGPT) or critical behavior has been simply reviewed and some signals of LGPT in heavy ion collisions, especially in NIMROD data, are focused. These signals include the power-law charge distribution, the largest fluctuation of the fragment observables, the nuclear Zipf law, caloric curve and critical exponent analysis etc. 相似文献
57.
Edwin Y.B.Pun 《复旦学报(自然科学版)》2007,(5)
1 Results Rare earth doped waveguide amplifiers and devices have been demonstrated in silica, crystal and other glass hosts. These rare earth doped optical waveguide devices are based on inorganic materials. Many processing steps are required and can lead to long fabrication time and low yield.Polymer materials offer many distinct properties compared to inorganic materials, such as ease of fabrication, low production costs, simple processing steps, and compatibility with micro-fabrication technologies. ... 相似文献
58.
Summary An alcaloid C16H19NO3 has been isolated fromErythrina tholloniana; the iodohydrate of this erythroidine has a melting point of 225°C and 239°C for its chlorhydrate. It has a powerful curare-like action on the frog or on its isolated sciatic-sartorius preparation; at a concentration of less than 1/1,000,000, a complete neuromuscular block is produced: the electrical stimulation of the motor nerve does not produce any contraction, but the muscle reacts by an end-plate potential having the same characteristics (shape, duration, possibility of summation) as the electrical waves produced in the same preparation curarized by ordinary curare or by quaternary ammonium derivatives. Decurarization by veratrine 1/200,000 is accompanied by the same electrical reactions as those which have been described in preparations treated by curare.On mammals, the alcaloid has little curariform activity; on the isolated phrenic-diaphragm preparation of the rat, incomplete block was produced at a concentration of 1/5000. 相似文献
59.
60.