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81.
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83.
Peeling Layers of an Onion: Inventory Model with Multiple Delivery Modes and Forecast Updates 总被引:7,自引:0,他引:7
This paper is concerned with a periodic review inventory system with fast and slow delivery modes and regular demand forecast updates. At the beginning of each period, on-hand inventory and demand information are updated. At the same time, decisions on how much to order using fast and slow delivery modes are made. Fast and slow orders are delivered at the end of the current and the next periods, respectively. It is shown that there exists an optimal Markov policy and that it is a modified base-stock policy. 相似文献
84.
We examine the component procurement problem in a single-item, make-to-stock assembly system. The suppliers are uncapacitated and have independent but non-identically distributed stochastic delivery lead times. Assembly is instantaneous, product demand follows a Poisson process and unsatisfied demand is backordered. The objective is to minimize the sum of steady-state holding and backorder costs over a pre-specified class of replenishment policies. To keep the analysis tractable, we impose a synchronization assumption that no mixing occurs between sets of component orders. Combining existing results from queueing theory with original results concerning distributions that are closed under maximization and translation, we derive a simple approximate solution to the problem when lead time variances are identical. In simulations, our derived policy is within 2% of optimal and significantly outperforms policies that ignore either component dependence or lead time stochasticity. It is also quite robust with respect to various model assumptions, except the synchronization one. 相似文献
85.
安全因子优化与协调模型研究 总被引:7,自引:3,他引:4
在需求和供应都不确定的情形下 ,通过模型研究对两阶供应链的安全因子优化与协调作了一些有益的探讨 .本文引入了有效库存水平的概念 ,以反映上游缺货对下游库存的影响 ,在基准库存水平补货模式下构造了的供需双方的库存模型 ,且对安全因子进行整体优化以降低供应链的库存成本 . 相似文献
86.
This paper treats the problem of determining optimal level of transaction balances in a decentralized firm. In conformity with the practices of such firms, cash generated at dispersed location is concentrated at central locations prior to short-term investment and borrowing. Under deterministic assumptions, an optimal transfer/investment is derived and a simple procedure for determining optimal parameters is described. 相似文献
87.
We consider a single-period multi-location inventory system where inventory choices at each location are centrally coordinated.
Transshipments are allowed as recourse actions in order to reduce the cost of shortage or surplus inventory after demands
are realized. This problem has not been solved to optimality before for more than two locations with general cost parameters.
In this paper we present a simple and intuitive model that enables us to characterize optimal inventory and transshipment
policies for three and four locations as well. The insight gained from these analytical results leads us to examine the optimality
conditions of a greedy transshipment policy. We show that this policy will be optimal for two and three locations. For the
n location model we characterize the necessary and sufficient conditions on the cost structure for which the greedy transshipment
policy will be optimal.
相似文献
88.
折扣支付部分拖后供给量的易变质物品经济批量模型 总被引:1,自引:0,他引:1
王圣东 《数学的实践与认识》2007,37(11):32-37
在假定备运期间费用函数为备运时间一般函数的前提下,将备运期和折扣率作为决策变量,建立了折扣支付部分拖后供给量的易变质物品经济批量模型,给出了寻求最优备运期、最优折扣率及最优订购周期的简单方法,并给出了参数的灵敏度分析和应用实例. 相似文献
89.
This paper deals with an unreliable manufacturing system in which no backlog is allowed. The hedging point policy is used to control production. This paper's objective is to find the optimum hedging point so as to minimize the average inventory cost. Firstly, for a tentative hedging point, we derive the limiting distribution of the inventory level. This derivation is accomplished by comparison between this system and a finite storage-production system. Based on it we calculate the average inventory cost and find the optimum hedging point.This research was supported in part by the National Natural Science Foundation of China. Bin Liu was partially supported by ITDC, contract No. 105-82150. 相似文献
90.
供应商管理库存的渠道利润优化分析 总被引:1,自引:0,他引:1
本文研究了供应链管理的渠道利润问题。对有确定需求、有初始库存和库存短缺的一种畅销商品,建立了供应商管理库存的渠道利润模型。通过对此模型的进一步分析,证明了在短期激励下供应商管理库存的渠道利润优于一般库存的渠道利润;也证明了在长期激励下,供应商管理库存可以产生比短期激励下更优的渠道利润,也优于一般库存的渠道利润。这一结果对于供应链环境下的库存管理在理论和工程上具有实际意义。 相似文献