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71.
退货情形下基于替代率的两产品联合订货决策研究 总被引:1,自引:0,他引:1
研究了一类在产品订货模型中考虑客户退货和产品间替代的两产品联合最优订货决策问题.假定客户以一概率退回其所购产品,退货产品经修复后可重新在市场上进行销售,销售期末未售出的商品只能在二级市场上降价处理,且不同产品间存在替代关系,销售商以自身利润最大化为目标确定两产品的订货量,得到其最优订货量及一些性质.研究结果表明:在允许退货的背景下,替代策略的采用将会进一步提高销售商利润. 相似文献
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In this paper, we propose the treatment of complex reservoir operation problems via our newly developed tool of fuzzy criterion
decision processes. This novel approach has been shown to be a more flexible and useful analysis tool especially when it is
desirable to incorporate an expert’s knowledge into the decision models. Additionally, it has been demonstrated that this
form of decision models will usually result in an optimal solution, which guarantees the highest satisfactory degree. We provide
a practical exemplification procedure for the models presented as well as an application example. 相似文献
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77.
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
78.
For a tandem line of finite, single-server queues operating under the production blocking mechanism, we study the effects
of pooling several adjacent stations and the associated servers into a single station with a single team of servers. We assume
that the servers are cross-trained (so that they can work at several different stations) and that two or more servers can
cooperate on the same job. For such a system, we provide sufficient conditions on the service times and sizes of the input
and output buffers at the pooled station under which pooling will decrease the departure time of each job from the system
(and hence increase the system throughput). We also show that pooling decreases the total number of jobs in the system at
any given time and the sojourn time of each job in the system if the departure time of each job from the system is decreased
by pooling and there is an arrival stream at the first station. Moreover, we provide sufficient conditions under which pooling
will improve the holding cost of each job in the system incurred before any given time, and extend our results to closed tandem
lines and to queueing networks with either a more general blocking mechanism or probabilistic routing. Finally, we present
a numerical study aimed at quantifying the improvements in system performance obtained through pooling and at understanding
which stations should be pooled to achieve the maximum benefit. Our results suggest that the improvements gained by pooling
may be substantial and that the bottleneck station should be among the pooled stations in order to obtain the greatest benefit.
AMS subject classification: 90B22 相似文献
79.
We study a dynamic inventory and pricing optimization problem in a periodic review inventory system with setup cost and finite ordering capacity in each period. We show that the optimal inventory control is characterized by an (s,s′,p) policy in four regions of the starting inventory level. 相似文献
80.
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