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91.
供应商管理库存(VMI)是一种在用户和供应商之间的合作性策略。通过策略选择、实施目标分析及协议制定三个角度分析研究,设计实施的南方液压公司VMI模式全程方案,可有效提升南方液压公司的库存管理水平。 相似文献
92.
93.
以供应链博弈理论为背景,研究上游企业向下游企业提供知识型产品的二级供应链协调问题,上游企业是斯塔博格博弈的领导者,下游企业是跟从者。上游企业需要在一系列的收费和成本分担的方式中选择一种使供应链系统高效运作的方式。通过研究发现:上游企业对下游企业生产的产品收取一定费用并对下游企业未售库存给予一定补贴能够使供应链协调并使自己的利润最大化。 相似文献
94.
Vibrio anguillarum , an opportunistic fish pathogen, is the main species responsible for vibriosis, a disease that affects feral and farmed fish and shellfish, and causes considerable economic losses in marine aquaculture. In this study, we used polymerase chain reaction (PCR) to detect V. anguillarum . PCR specificity was evaluated by amplifying the rpoS gene, a general stress regulator, in six strains of V. anguillarum and 36 other bacterial species. PCR amplified a species-specific fragment (689 bp) from V. anguillarum . Furthermore, the PCR assay was sensitive enough to detect rpoS expression from 3 pg of genomic DNA , or from six colony-forming units (CFU) mL−1 of cultured V. anguillarum . However, the assay was less sensitive when genomic DNA from the infected flounder and prawn was used (limit of detection, 50 ng and 10 ng g−1 tissue, respectively). These data demonstrate that PCR amplification of the rpoS gene is a sensitive and species-specific method to detect V. anguillarum in practical situations. 相似文献
95.
AIM and METHODS: The ratio of mitochondrial DNA (mtDNA) deletion was measured to find the relationship between mtDNA deletion and aged learning and memory deficit. The aged rats were divided into two groups, aged learning and memory deficit group and aged learning and memory normal group. The ratio of mtDNA deletion was measured by dilution polymerase chain reaction. RESULTS: There are deleted mtDNA (about 4834 bp) in the cerebral cortex, hippocampus and cerebellum of both young and aged rats. The ratios of deleted mtDNA were similar in the cerebral cortex,hippocampus and cerebellum of young rats (about 0.00018%). The ratio mtDNA of aged learning and memory normal rats had increased by five-fold in the cerebral cortex and hippocampus, or one-fold in the cerebellum over young rats. The ratio of aged learning and memory dificit rats had increased by one-fold in the cerebral cortex or 0.8-fold in the hippocampus or two-fold in the cerebellum over aged learning and memory normal rats.CONCLUSIONS: There was really the increase of mtDNA in aging rat brain. And this increase was double in amount in aged learning and memory deficit rats compared to the normal learning and memory aged rats. It is suggested that the mtDNA deletions in the brain regions associated with learning and memory may be contributed to the cellular and molecular mechanism of learning and memory deicit with aged rats. 相似文献
96.
Kullapapruk Piewthongngam Supachai Pathumnakul Kanchana Setthanan 《Agricultural Systems》2009,102(1-3):58-66
The poorly integrated cane supply planning between mills and cane growers in the Northeast of Thailand generates an excess of cane supplies that exceeds the mills’ capacity during the peak of harvest season. Each grower individually determines his/her cultivation plan by selecting planting dates and cultivars based on one’s own preference without taking into account the individual mill’s capacity and other growers’ plans. This situation causes most sugarcane grown in this area to reach its mature stage at the same period. In this study, we propose a framework of cultivation planning to cope with the problem. The focus of the cultivation plan is a long-term plan to determine the cultivation time, the cultivar selection and the corresponding prospective harvesting time window for each field such that overall sugar production is optimized.The crop growth model and a mathematical model are employed for yield simulation and optimization task. The crop growth model enables decision-makers to visualize cane production of each individual field at different dates with different cultivars and allow decision-makers to apply the mathematical programming to cultivation planning. The suggested framework has the potential to increase sugar production by 23% when compared to the traditional method. 相似文献
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98.
在分析了农业装备物流体系特点的基础上,指出了目前存在的数学模型不能完全体现和描述农业装备物流体系的特点;建立了基于面向环境时延着色Petri网(EOCTPN)的农业装备物流体系数学模型;研究了不同类型农业装备物流体系对库存总成本和长鞭效应的影响程度;解决了目前存在的无法将正向物流和逆向物流有机结合在一起的问题;有效克服了基础Petri网描述此类问题出现的"节点爆炸"现象.在仿真实验的基础上,提出了应如何构建农业装备物流体系的方法. 相似文献
99.
我国民营制胶企业是天然橡胶产业的重要组成部分,而供应链管理的落后严重制约了企业的发展,本文针对民营制胶企业供应链管理中的问题,提出了优化方案。 相似文献
100.
江苏小麦全蚀病菌生物学特性的初步研究 总被引:1,自引:0,他引:1
对江苏滨海、响水、灌云和盱眙等县5个菌株研究结果表明,小麦全蚀病菌(Gaeumannomycesgraminis)生长适温在20~25℃之间,30℃生长受到明显抑制,35℃停止生长;适宜生长的pH范围较广,在pH5~9的范围内生长良好,以pH7~8最适宜;淹水条件下对全蚀病菌生长有较强的抑制作用,当平均气温28℃以上(日最高温达37.5℃),受淹病菌即死亡;全蚀病菌对有机氮利用较铵态氮和硝态氮好;硫酸铵对全蚀病菌的抑制作用是由于高浓度和改变基质pH两方面的因素。不同来源菌株间在生长适温、pH及对淹水的反应存在明显差异 相似文献