关于非齐次有消费的投入产出模型的若干极限性质

进一步研究有消费情形的非齐次投入产出模型。给出了最初年份的投入产综与最终年份的投入产综的极限关系，并得到了最终年份投入产综的增长速度和产出产综的近似表达式。     

考虑消费者退货的双渠道订货量决策研究

在考虑消费者退货下,构建由制造商和零售商组成的二级供应链模型,研究了双方的订货量决策问题,并分析不同策略以及决策顺序对均衡结果和制造商开通直销渠道的影响。研究发现:在单渠道中,提供退款保证可提高订货量、制造商和零售商利润。当直销成本较大时,制造商将不开通直销渠道;提供退款保证有利于制造商开通直销渠道。在双渠道中,提供退款保证能够提高直销量、总订货量和制造商利润;直销量、总订货量、制造商利润和总利润都随直销成本递减;在顺序决策下,制造商利润和总利润更高。     

需求信息非对称情况下零售商最优订货问题研究

考虑需求信息非对称环境下多个存在竞争的零售商的最优订货问题,每个零售商的需求分布函数未知,传统的通过最大化期望利润来求解最优订货量的方法此时不再适用,转而应用稳健优化中使用的方法-最小化最大后悔值方法.首先给出了零售商最优订货量的一般形式.其次考虑了问题的两种特殊情形:对称博弈、两个零售商的最优订货模型,得到:对称博弈存在Nash平衡点、竞争使得零售商订货量增大、信息不对称使得零售商订货量降低并且零售商的最优订货量在一定条件下会随回收残值的增大而增大;两个零售商最优订货模型下的最优订货量的具体形式.     

一个带有增加量价格折扣的两货栈库存模型

已有的确定性两货栈(其中一个是自己货栈(OW);另一个是租用货栈(RW))库存模型通常不考虑增加量价格折扣,然而在实际生活中,增加量价格折扣却是促使库存管理者加大订货量的一个重要原因.本文通过考虑增加量价格折扣而将两货栈系统作了进一步扩展,在采用间隔式运输模式运送RW的物品到OW的情形下,建立了一个带有增加量价格折扣并允许短缺的两货栈库存模型,提供了一种寻求最优库存策略的简单方法.     

The multi-period newsboy problem

We will try to generalize the so-called newsboy model so that we can deal with unsatisfied demand or unsold quantity. Consider the time interval that consists of multiple ordering cycles. Assume that the probability density function of demand is given for each cycle. Then our problem is to make the ordering plan with which we can maximize the expected profit. In the classical newsboy model ordering quantity is always equal to the (planned) initial inventory level. But if we take account of unsatisfied demand and unsold quantity, the (desired) ordering quantity must be determined by a proper stochastic rule. Then, in stead of determining the ordering quantity of each cycle, we must plan the initial inventory level so that the expected profit may be maximized. If unsold exists in present cycle, the ordering quantity of next cycle becomes smaller than the planned inventory level. And if unsatisfied demand exists in the present cycle, the ordering quantity of next cycle becomes larger than the planned inventory level.     

基于数量折扣合同和缺货损失的EOQ模型的改进

经济订购批量模型假定需求率、单位持有成本、订货成本为常数下得到总成本最低的订购批量,这些参数常数化的假设在现实中通常难以满足.假定需求和订货费为不确定的、库存成本包括年固定成本(与订货量无关)和年可变成本(与订货量有关),用三角模糊数表示年需求和订货费,通过引入数量折扣合同来量化单位产品进价,分别在不允许缺货和考虑缺货损失两种情况下得到最佳订货量.最后的算例表明了模型的合理性.     

基于排队论的内场维修设备数量确定方法

在内场车间维修设备配置研究中,为了科学合理地确定维修设备数量需求,运用排队论的基本方法,结合飞机内场维修工作特点,提出了基于排队论的内场维修设备数量确定方法,构建了相应的数量确定模型,结合实例验证了该方法可行有效.结果表明方法可以提高飞机基层级内场车间维修设备数量确定的准确性.     

An EOQ model for deteriorating items under supplier credits linked to ordering quantity

In the classical inventory economic order quantity (or EOQ) model, it was assumed that the purchaser must pay for the items received immediately. However, in practices, the supplier usually is willing to provide the purchaser a permissible delay of payments if the purchaser orders a large quantity. As a result, in this paper, we establish an EOQ model for deteriorating items, in which the supplier provides a permissible delay to the purchaser if the order quantity is greater than or equal to a predetermined quantity. We then characterize the optimal solution and provide an easy-to-use algorithm to find the optimal order quantity and replenishment time. Finally, several numerical examples are given to illustrate the theoretical results.     

不同情形下供应链优化决策模型的比较分析

本文提出三种不同情形（制造商与零售商追求各自利润最大化，并且没有价格折扣策略；制造商与零售商共同追求总利润最大化，不实施价格折扣策略；制造商与零售商共同追求总利润最大化，并实施价格折扣策略）下供应链价格和库存补充策略的优化决策模型，并通过具体数例进行比较分析，结果表明，供应链合作并实施价格折扣策略时的供应链总利润最高，而供应链双方利润分配系数的变化对基于供应链总利润最大化的供应链优化决策没有影响．     

基于存货质押的库存管理研究

针对基于存货质押的库存管理问题进行分析并构建模型,从还贷和不还贷两个角度,研究模型的最佳订货批量和质押量.模型以利润函数为目标函数,利润函数包括了销售额、缺货损失、剩余品价值、产品成本以及贷款本息和.通过对利润函数进行求解,得出最佳订购批量、存货质押量和最大期望利润,最后根据利润的大小决定是否偿还贷款.     

基于腐损程度的季节性产品动态定价与订单量的集成优化

为了对易腐季节性产品的销售价格和订单量进行最优决策,考虑产品在不同腐损程度的情形下,需求与价格和时间同时相关的一类季节性产品的动态定价和订单量的集成优化问题.建立该类产品的价格制订次数、每次制订的价格和订单量的集成优化模型,并对模型进行求解,最后结合数例验证模型的实用性和可操作性,并分析产品腐损程度对价格制订次数、价格大小、订单量和利润的影响.结果表明,随着产品腐损程度的提高,零售商在销售季节内的产品价格最优制订次数保持不变;零售商在销售季节内所制订的最优价格逐渐微降;产品的最优订单量和所产生的最优利润逐渐微升.     

Lot Sizes for One-Time-Only Sales

The order quantity which minimizes discounted cash flows for a one-time-only sale is determined. Current inventory may be at or exceed the usual reorder point when the sale is consummated. In the latter case, the company may decide to buy nothing, especially if a large minimum order quantity is required in order to obtain the price discount. The same model can also be used to handle the case of an impending price increase. Exact and approximate solutions are presented which recommend the order quantity, the associated cost savings, minimum acceptable percentage price discount and minimum vendor quantity requirements.     

Optimal inventory decisions in a multiperiod newsvendor problem with partially observed Markovian supply capacities

This paper considers a multi-period news-vendor problem with partially observed supply-capacity information which evolves as a Markovian Process. The supply capacity is fully observed by the buyer when the capacity is smaller than the buyer’s ordering quantity. Otherwise, the buyer knows that the current-period supply capacity is greater than its ordering quantity. Based on these two observations, the buyer updates the future supply-capacity forecasting accordingly. With a dynamic programming formulation, we prove the existence of an optimal ordering policy. We also prove that the optimal order quantity is greater than the myopic order quantity.     

合肥市出租车数量确定的模型及应用研究

本提取了十个城市出租车数量的合理因素，运用非线性规划，建立了确定合肥市出租车数量的动态数学模型，计算出影响出租车数量因素的权重，最终得到了一个比较符合实际的结果，该结果已为合肥市出租车数量的控制提供了决策支持。     

Economic order quantity under conditionally permissible delay in payments

Within the economic order quantity (EOQ) framework, the main purpose of this paper is to investigate the retailer’s optimal replenishment policy under permissible delay in payments. All previously published articles dealing with optimal order quantity with permissible delay in payments assumed that the supplier only offers the retailer fully permissible delay in payments if the retailer ordered a sufficient quantity. Otherwise, permissible delay in payments would not be permitted. However, in this paper, we want to extend this extreme case by assuming that the supplier would offer the retailer partially permissible delay in payments when the order quantity is smaller than a predetermined quantity. Under this condition, we model the retailer’s inventory system as a cost minimization problem to determine the retailer’s optimal inventory cycle time and optimal order quantity. Three theorems are established to describe the optimal replenishment policy for the retailer. Some previously published results of other researchers can be deduced as special cases. Finally, numerical examples are given to illustrate all these theorems and to draw managerial insights.     

A generalized discount structure and some dominance rules for selecting the price-break EOQ

This paper introduces a generalized discount structure that combines the features of incremental and all-units quantity discount policies. General properties of the EOQ model under this discount structure are studied, and dominance rules for comparing order quantity intervals under either type of discount policy are established. In addition, procedures for developing an iso-cost function and the minimal feasible set for optimal order quantity are proposed.     

关于无穷小量乘积的讨论

本文由有限个无穷小量的乘积仍是无穷小量的证明入手 ,给出无穷多个无穷小量的乘积不一定是无穷小量的例子 ,并根据这种方法得到无穷多个无穷大量的和也不一定是无穷大量的结论     

大窑湾入境集装箱量及疫情集装箱量的模糊预测研究

作为国际海运和物流业的主要装载工具集装箱是入境统计以及检验检疫的主要对象.按特定规律统计的集装箱量时间序列既有一定的统计规律,又有较大的随机性.采用模糊时间序列方法,通过构造论域、模糊集以及提出多重计算规则,对2005年6月至2012年10月大窑湾入境集装箱量、疫情集装箱量,以及疫情与入境集装箱量比值时间序列进行了模糊分析与预测.预测值与实际值的比较说明了算法的有效性.预测值与实际值的平均绝对误差、平均绝对百分误差从整体上揭示了时间序列自身的模糊性和模型的合理性.     

多元Lanchester方程在装备战损量预计中的应用

在战时装备保障中,装备战损量预计是一难点问题.本文从分析影响装备战损的因素出发,采用多元Lanchester方程寻求解决方案.提出了基于指数多元Lanchester方程的装备战损量预计模型和模型中毁伤系数的确定方法.据此,建立了一种新的装备战损量预计方法,并举例验证.该方法较好的满足了未来信息化条件下作战装备保障的需要,具有重要的参考价值.     

需求中断下具零售商激励的双渠道供应链价格与生产决策

研究了由一个制造商和一个零售商所组成的两周期双渠道供应链.在第一周期需求实现之前,建立了生产量;在第二周期,基于第一周期的生产量和需求的实现确定了最优销售价格,进而确定了最优的生产量,实现了生产量的优化.通过需求中断下制造商和零售商的垂直整合,讨论了中断情形下价格和生产量对利润的影响.实证结果证实,集中式供应链的最优价格决策受零售渠道顾客偏好和市场规模变化的影响较为显著.