共查询到16条相似文献,搜索用时 140 毫秒
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考虑提前期内需求为模糊随机变量且提前期为可缩短情形下,建立由购买商和供应商所组成的简单供应链连续库存补货策略优化模型,其中订单量、再订货点和提前期为决策变量.首先推导出模糊随机需求条件下购买商和供应链的成本函数,然后,进一步考虑总需求为三角模糊数,推导出供应商、购买商和供应链的模糊成本函数.在此基础上分别从购买商成本最小和供应链成本最小角度对模型进行求解,结合具体算例对模型进行应用分析和比较分析,结果表明模型具有有效性和实用性,并得出如下结论:从购买商本身角度考虑订购策略所产生的供应链成本总是大于从供应链整体角度考虑订货策略所产生的供应链成本,同时从购买商本身角度考虑订货策略所产生的最优订购量、购买商成本低于从供应链整体角度考虑订货策略所产生的最优订购量、购买商成本. 相似文献
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刘国志 《数学的实践与认识》2006,36(12):1-5
提出一个新的具有积压定单的关于模糊订购量的模糊存储模型.在模糊函数原理下,给出了模糊总存储成本.为了寻找最优解,把最优模糊存储模型转化为双目标最优化模型,利用L ingo8.0求解不等式约束问题,我们发现最优解都是确定的实数.此外,当模糊订购量和模糊总需求都是三角形(或权重均为1/2梯形)模糊数时,我们提出模型的最优解与经典的具有积压定单存储模型具有相同的结果. 相似文献
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随机提前期随机需求条件下的二级库存模型 总被引:5,自引:0,他引:5
考虑由一个分销中心和若干零售商组成的两级分销系统 ,假设分销中心和零售商实行连续性盘点、( R,Q) 订货策略 ,分销中心的交货时间是常量 ,而零售商处的提前期为随机变量 ,且需求服从独立的复合泊松过程 .以整个系统平均成本最小为目标函数 ,由此得到最优的订货策略 ,并且给出数值例子及敏感性分析 . 相似文献
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4.3基于安全库存量的随机模型 本段讨论随机需求及有常数供货滞后时间的库存模型.由于需求的随机性,缺货总是可能的.直观上容易想到,我们在订货时应该既要考虑到滞后时间中的平均需求量,又要顾及需求可能出现的波动性.这种随机的波动性通过下面将要引出的安全库存量来加以控制.通过安全库存量的选择,在一定的费用结构下可以使系统的运行状况最佳. 下面分别讨论几种典型的情形. 4.3.1(s,Q)订货策略,Q已知. 模型假定: a)连续盘点。系统在稳态下进行. b)供货滞后时间是常数L,缺货事后补足. c)需求是平稳的;在一个长度为L的时间间隔中的需求量… 相似文献
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分销仓储配送中心定货决策模拟系统研究 总被引:4,自引:0,他引:4
本对于分销仓储本着中心在客户需求量和再订货提前期都是随机性的情况,利用Arena模拟软件,通过对再订货点模型进行了模拟,求出可使系统成本较少的订购批量及再订货点存货水平的组合,从而确定最佳订货策略,解决现实中这种“双随机性”的复杂订货决策问题。 相似文献
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In this paper, a periodic review inventory system has been analyzed in a mixed imprecise and uncertain environment where fuzziness and randomness appear simultaneously. A model has been developed with customer demand assumed to be a fuzzy random variable. The lead-time has been assumed to be a constant. The lead-time demand and the lead-time plus one period’s demand have also been assumed to be fuzzy random variables. A methodology has been developed to determine the optimal inventory level and the optimal period of review such that the total expected annual cost in the fuzzy sense is minimized. A numerical example has been presented to illustrate the model. 相似文献
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In this paper, we assume that the demands of different customers are not identical in the lead time. Thus, we investigate a continuous review inventory model involving controllable lead time and a random number of defective goods in buyer’s arriving order lot with partial lost sales for the mixtures of distributions of the lead time demand to accommodate more practical features of the real inventory systems. Moreover, we analyze the effects of increasing investment to reduce the lost sales rate when the order quantity, reorder point, lost sales rate and lead time are treated as decision variables. In our studies, we first assume that the lead time demand follows the mixture of normal distributions, and then relax the assumption about the form of the mixture of distribution functions of the lead time demand and apply the minimax distribution free procedure to solve the problem. By analyzing the total expected cost function, we develop an algorithm to obtain the optimal ordering policy and the optimal investment strategy for each case. Finally, we provide numerical examples to illustrate the results. 相似文献
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VMI条件下具有复合二项随机需求的销售商库存策略研究 总被引:1,自引:0,他引:1
考虑一个典型的单一产品的二级供应链系统:单供应商对单销售商,假定系统中销售商的需求分布为复合二项分布,未满足的需求机会损失;补货间隔时间为一随机变量.本文采用概率方法对销售商的需求分布、期望缺货、期望库存周期及库存的稳定性分布进行研究的基础上,构建了使单位时间内销售商的期望库存成本费用最小的库存模型,由此模型便可确定VMI模式下供应商对销售商的库存补货参数s和S,并且给出了在补货响应时间为泊松分布的情况下模型的求解算法,还给出了及时补货响应情况下的5个算例.为补货策略的实施提供了一种简单易于控制的思路和方法. 相似文献
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D. Sculli 《The Journal of the Operational Research Society》1980,31(10):889-893
Stock level frequency distributions are derived for continuous review stock control policies in which the lead time demand is normally distributed. The percentage points of the distributions have been tabulated, and the table can be used to determine the reorder point that will meet a specified customer order quantity from stock with a specified probability. The results can also be used to determine the order up to point for a periodic review policy and the reorder point for a mixed policy. 相似文献
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This paper considers a single-echelon inventory system with a warehouse facing compound Poisson customer demand. Normally the warehouse replenishes from an outside supplier according to a continuous review reorder point policy. However, it is also possible to use emergency orders. Such orders incur additional costs but have a much shorter lead time. We consider standard holding and backorder costs as well as ordering costs. A heuristic decision rule for triggering emergency orders is suggested. The decision rule minimizes the expected costs under the assumption that there is only a single possibility for an emergency replenishment, but the rule is used repeatedly as a heuristic. Given a certain reorder point policy for normal replenishments, our decision rule will always reduce the expected costs. A simulation study illustrates that the suggested technique performs well under different conditions. 相似文献