可替代产品库存模型的研究

市场上,很多产品之间可相互替代,商家为了获得的更多的利润,经常会用一种产品替代另一种产品.不仅如此.某种产品缺货时,也可以重新进货以满足顾客的需求.我们从销售商的角度,讨论这两个因素对库存策略的影响,建立了这类问题有两个产品的单周期的利润最大化模型,证明了目标函数是凹的和子模的,从而问题的解是存在的,给出了最优订货量(原始库存)的必要条件,讨论了各参数对库存的影响.通过比较,证明了商家采取替代策略和允许再订货可以提高利润并且可减少库存总量.     

需求不确定的供应链两阶段订货模型

销售商如何在不确定需求的市场环境下根据制造商提供的订货条件进行合理订货是供应链管理的一个核心问题。本文利用信号博弈的原理从销售商的角度研究在不确定需求且传统需求预测方法失效的情况下，允许调整订货量的短生命周期产品两阶段订货模型，得到了在两次订货条件下销售商应该采取的最优订货量与调整策略以及制造商对契约灵活性限制的成本函数。     

带有随机订货点的两阶段报童模型

销售商可通过二次订货以达到降低风险、增加利润的目的,然而在实际中由于生厂商供货能力不足等不可控因素,销售商往往无法确定何时能进行第二次订货。针对这种现象,本文研究二次订货时间不确定的报童问题,假设随机订货时间点和需求率均服从均匀分布,建立了带有随机订货点的两阶段报童模型,给出了两阶段最优期望总订货量,使得零售商在整个销售期内的期望利润达到最大值。最后通过数值算例,对比分析了本文的二次订购模型与传统一次订购模型,研究结果指出在整个销售期内二次订货可以提高零售商的期望利润。     

网络直销模式下含有管理复原退货物流的库存问题研究

本文采用定期库存控制策略研究了需求服从均匀分布、订货周期与再制造周期不相等情况下的含有管理复原退货物流的库存问题。在考虑退货价格对需求的影响的情况下，本文建立了以使期望利润最大化为目标，对退货价格、订货量、订货周期和再制造周期进行同时进行决策的库存模型。本文通过数值算例分析了退货价格对需求的影响因子的大小以及退货率的大小分别对利润、最优退货价、最优订货量、最优订货周期和最优退货处理周期的影响。结果指出，商家在制订库存策略时应该考虑退货价对需求的影响，并且应首先确定退货率和退货价对需求影响因子的大小。     

考虑消费者低碳偏好的可替代产品订货决策

基于产品的可替代性,考虑零售商有无能力限制两种情况,订购环境质量和价格不同的两种产品,建立利润最大化模型,确定两种产品的最优订货量和消费者低碳偏好对其的影响.理论分析表明:库存能力的提高使得订货量增大,订单数量和利润随环境质量的变化而变化;算例计算的结果验证了模型的合理性,数值分析表明:提高库存容量和订购替代率大的两种产品有利于利润的增加,当库存无容量限制时,订货量和销售商利润水平不再受容量变化的影响.     

考虑客户违约情况下的易逝品超售决策研究

在产能固定的情况下,考虑两类客户no show的随机性,建立了两类客户no show情况下易逝品的超售决策模型,得到了订货量的最优解.算例分析结果表明:普通客户单位订货价格对最优订货量有显著影响,而VIP客户的单位订货价格只有超过一定值时,才能显著影响最优订货量;两类客户的单位补偿对最优订货量的影响都较小;两类客户的短缺成本对最优订货量均有明显影响,相比而言,普通客户的短缺成本对最优订货量的影响更大.     

基于不同风险偏好的退货可再销报童模型研究

考虑退货可再销售的情况下,应用条件风险价值(CVaR),构建纳入不同风险偏好的报童模型,并给出了不同环境下的最优订货量.通过解析和数值仿真,进一步分析了决策者的风险偏好水平、产品退货率以及残值对最优订货量决策的影响.研究结果表明:最优订货量随着决策者风险追逐偏好水平的增加而增加,随着风险规避偏好水平的增加而减小;最优订货量随着退货率的增加而减小,随着产品残值的增加而增加.结合订货决策的实际特点,给出了不同环境下的最优订货量,为决策者提供了全面且动态的决策建议.     

单向可替代产品价格和库存的联合决策

考虑单周期问题中零售商同时销售两种可单向替代的产品,以期望利润为目标函数建立数学模型.将库存和替代价格共同作为零售商决策变量,证明其目标函数是凹函数,并得到求模型最优解的充要条件及解存在的范围.最后假设产品需求为正态分布,通过数值实验对模型的最优解进行分析,结果表明:实行最优替代价格策略可以有效提高零售商期望利润;允许替代销售不一定提高市场服务水平;被替代产品的销售价格和残值对零售商的最优替代价格决策没有显著影响.     

替代价格可变的两产品库存问题研究

从销售商的角度出发,研究了可变替代价格下的两产品库存问题.假设随机需求服从均匀分布,得到了一些有益的结论,并通过数值计算说明了各参数的变化对最优订货量和替代价格的影响.     

基于等量订货的可替代易变质产品库存策略研究

零售商常常根据不同"年龄"的易变质产品质量的差异而制定不同的价格,从而会带来不同的顾客需求.而当某个"年龄"的产品缺货时,顾客可能会购买其他"年龄"的产品作为替代.在上述背景下,本文考虑某个销售季节内多周期等量订货策略,分别在单周期和多周期情况下找到了零售商的最优订货量.     

The newsboy problem with resalable returns: A single period model and case study

We analyze a newsboy problem with resalable returns. A single order is placed before the selling season starts. Purchased products may be returned by the customer for a full refund within a certain time interval. Returned products are resalable, provided they arrive back before the end of the season and are undamaged. Products remaining at the end of the season are salvaged. All demands not met directly are lost. We derive a simple closed-form equation that determines the optimal order quantity given the demand distribution, the probability that a sold product is returned, and all relevant revenues and costs. We illustrate its use with real data from a large catalogue/internet mail order retailer.     

The impact of consumer returns policies on consignment contracts with inventory control

We consider a consignment contract with consumer non-defective returns behavior. In our model, an upstream vendor contracts with a downstream retailer. The vendor decides his consignment price charged to the retailer for each unit sold and his refund price for each returned item, and then the retailer sets her retail price for selling the product. The vendor gets paid based on net sold units and salvages unsold units as well as returned items in a secondary market. Under the framework, we study and compare two different consignment arrangements: the retailer/vendor manages consignment inventory (RMCI/VMCI) programs. To study the impact of return policy, we discuss a consignment contract without return policy as a benchmark. We show that whether or not the vendor offers a return policy, it is always beneficial for the channel to delegate the inventory decision to the vendor. We find that the vendor’s return policy depends crucially on the salvage value of returns. If the product has no salvage value, the vendor’s optimal decision is not to offer a return policy; otherwise, the vendor can gain more profit by offering a return policy when the salvage value turns out to be positive.     

Responsive pricing under supply uncertainty

Consider a retailer orders a seasonal product from a supplier and sells the product over a selling season. While the product demand is known to be a linear function of price, the supply yield is uncertain and is distributed according to a general discrete probability distribution. This paper presents a two-stage stochastic model for analyzing two pricing policies: No Responsive Pricing and Responsive Pricing. Under the No Responsive Pricing policy, the retailer would determine the order quantity and the retail price before the supply yield is realized. Under the Responsive Pricing policy, the retailer would specify the order quantity first and then decide on the retail price after observing the realized supply yield. Therefore, the Responsive Pricing policy enables the retailer to use pricing as a response mechanism for managing uncertain supply. Our analysis suggests that the retailer would always obtain a higher expected profit under the Responsive Pricing policy. In addition to examining the impact of yield distribution and system parameters on the optimal order quantities, retail prices, and profits under these two pricing policies, we analyze two issues arising from responsive pricing. The first issue deals with the case in which the retailer can place an emergency order with an alternative source after observing the realized yield, while the second issue deals with a situation in which the retailer has to allocate his order among multiple suppliers.     

Postponed two-pricing and ordering opportunity for selling a single season inventoried product

Postponement strategies are becoming increasingly important in light of a global trend in which products’ life-cycles are decreasing, such that even products that are not traditionally considered seasonal become “obsolete” within a short period of time (e.g., electronic devices, new cars). Our work addresses postponed-pricing and ordering decisions for a retailer who sells a newsvendor-type inventoried product, in a selling season that is divided into two sub-periods. The division of the selling season enables the retailer to on-line adjust her decisions when faced with a scenario (one that is highly prevalent in reality) in which potential demand changes (increases or decreases) following consumers’ experiences of the product in early stages of the selling season. We assume that the retailer has two opportunities for receiving shipments: prior to the first sub-period and prior to the second one. The retailer determines each order quantity (base-stock level) on the basis of the demand distribution for the corresponding sub-period. In each sub-period, after observing additional market signals, the retailer determines the price of the product for that sub-period. With the aid of a stochastic programming approach, we develop optimization problems and solution methods in order to obtain pricing and ordering decisions that maximize the expected profit of the retailer. We present an extensive numerical example that compares the suggested strategy to three alternative strategies, and conclude that price postponement and responsiveness to demand changes can each reduce leftovers and lost sales as well as substantially increase expected profit.     

基于供应商视角的提前订货协调研究

本文针对一个供应商和零售商组成的供应链系统,主要研究零售商如何设计提前订货折扣来吸引顾客提前订货;而供应商如何根据市场需求的不确定性,设计零售商提前订货资金的付款时间等问题。在供应商-Stackelberg框架下,以期望利润为目标,建立了相应的决策模型。通过对模型的分析求解,给出了不同市场环境下供应商要求零售商支付提前订货资金的策略。最后,用算例验证了模型和理论分析的可行性。     

Coordination mechanism for the supply chain with leadtime consideration and price-dependent demand

We study a coordination contract for a supplier–retailer channel producing and selling a fashionable product exhibiting a stochastic price-dependent demand. The product’s selling season is short, and the supply chain faces great demand uncertainty. We consider a scenario where the supplier reserves production capacity for the retailer in advance, and permits the retailer to place an order not exceeding the reserved capacity after a demand information update during a leadtime. We formulate a two-stage optimization problem in which the supplier decides the amount of capacity reservation in the first stage, and the retailer determines the order quantity and the retail price after observing the demand information in the second stage. We propose a three-parameter risk and profit sharing contract that coordinates the supply chain. The proposed contract permits any agreed-upon division of the supply-chain profit between the channel members.     

零售商主导的模糊供应链博弈——考虑销售努力的情形

以包含一个制造商与一个零售商的两级供应链为研究对象,考虑零售商居于主导地位并付出销售努力时供应链各成员的决策。结合经济环境的不确定性,将市场需求函数和制造商的制造成本、零售商的经营成本视为模糊变量;运用斯塔克尔伯格模型刻画零售商和制造商之间的博弈过程,并引入期望值模型、机会约束模型来解决最优决策问题;通过一个数值算例证明了供应链博弈模型的有效性。研究表明,在均衡结果中,考虑到零售商所承担的销售努力成本,其总体期望值利润相比于制造商而言偏低,但单位产品边际利润较高。原因在于,零售商的主导地位使其不仅通过销售努力提高产品销量,提高了供应链的整体利润,同时也能够采用压低批发价格的方式,使自身在供应链中获取更多收益。     

带有常数返回率的动态易逝品供应链协调模型

以动态易逝品为研究对象,探讨了由单个制造商单个零售商所组成的两层供应链生产订购协调问题.在假定零售商所售产品存在返回的前提下,分别建立了集中决策和分散决策模型,并证明了这两个模型解的存在唯一性.提出了一个两阶段的收益共享契约,该契约不仅能达到供应链协调,而且还能实现供应链两成员的"双赢".最后,通过数值实例来验证模型的结论并得出相关管理启示.     

Consignment contracting: Who should control inventory in the supply chain?

Consignment is a popular form of business arrangement where supplier retains ownership of the inventory and gets paid from the retailer based on actual units sold. The popularity of such an arrangement has come with some continued debates on who should control the supply chain inventory, the supplier or retailer. This paper aims at shedding light on these debated issues. We consider a single period supply chain model where a supplier contracts with a retailer. Market demand for the product is price-sensitive and uncertain. The supplier decides his consignment price charged to the retailer for each unit sold, and the retailer then chooses her retail price for selling the product. We study and compare two different consignment arrangements: The first allows the retailer to choose the supply chain inventory, together with her retail price, and is labeled as a Retailer Managed Consignment Inventory (RMCI) program; and the second calls for the supplier to decide the inventory, together with his consignment price, and is labeled as a Vendor Managed Consignment Inventory (VMCI) program. We show that with an RMCI program, the supply chain loses at least 26.4% of its first-best (expected) profit, while with VMCI, it loses just or no more than 26.4% of the first-best profit. Second, we demonstrate that both programs lead to an equal split of the corresponding channel profit between the supplier and the retailer. These results indicate that it is beneficial both to the supplier and to the retailer when delegating the inventory decision to the supplier rather than to the retailer in the channel.     

基于商业信用和回购契约的供应链最优化策略研究

本文考虑由单一供应商和零售商组成的供应链系统,当供应商为零售商提供回购契约,同时零售商又为下游顾客提供商业信用契约时,供应商如何设计回购契约来有效协调整个供应链,以及零售商又如何借助回购和商业信用契约来做出自身最优订货策略问题,并建立了相应的决策模型。通过模型分析,给出了供应商和零售商在四种情形下的最优契约设计参数,以及零售商的最优订货决策。研究发现,当满足一定的参数范围时,供应链中两主体同时采用协调契约能够更加有效地增加整个供应链中的订货量和利润,为各主体创造更多新的价值。最后,本文结合数值例子,分析了模型参数变化对最优订货策略和各主体利润的影响。