The Effects of Sharing Upstream Information on Product Rollover

The process of introducing new and phasing out old products is called product rollover. This paper considers a periodic‐review inventory system consisting of a manufacturer and a retailer, where the manufacturer introduces new and improved products over an infinite planning horizon using the solo‐roll strategy. We consider two scenarios: (1) the manufacturer does not share the upstream information about new‐product introduction with the retailer and (2) the manufacturer shares the information. For each scenario, we first derive the decentralized ordering policy and the system‐optimal ordering policy with given cost parameters. We then devise an optimal supply chain contract that coordinates the inventory system. We demonstrate that when the inventory system is coordinated, information sharing improves the performance of both supply chain entities. However, this may not be true if the inventory system is not coordinated. We also show that under the optimal contract, the manufacturer has no incentive to mislead the retailer about new‐product information in the information‐sharing model. When demand variability increases, information sharing adds more benefits to the coordinated supply chain. Our research provides insights about coordinating product, financial, and information flows in supply chains with product rollover.     

基于“搭便车”行为的双渠道供应链库存竞争和促销策略

本文建立了由一个制造商和一个零售商组成的双渠道供应链模型，研究了随机需求下"搭便车"行为和渠道间缺货替代行为对供应链库存竞争与促销决策的影响。结果表明：分散式决策下，网络渠道替代率越高，零售商的最优订购量越大，同样的零售渠道替代率越高，制造商会为网络渠道提供更多的库存；而"搭便车"行为对零售商与制造商订购量的影响则取决于渠道替代率的变化，但"搭便车"行为会降低零售商促销努力水平。数值分析发现：分散式决策下，零售商最优订购量随"搭便车"行为的增加而减少。然而制造商的最优库存量并非随着"搭便车"行为程度的增加而增加，不同的是制造商网络渠道最优库存量取决于市场需求对传统零售渠道促销努力水平的弹性系数，即制造商网络渠道最优库存量随"搭便车"行为的增加先增加后减少。通过比较发现在不同的"搭便车"行为程度、传统零售渠道替代率、网络渠道替代率下，集中式决策下供应链期望收益大于分散式决策下供应链期望总收益。     

基于库存分担策略的装配系统准时供货模型研究

本文考虑一个由多供应商和单制造商构成的装配系统。当市场的需求时间无法确定时,制造商通过对供应商设定合理的库存分担策略来降低自身成本,供应商则需要自行决定对制造商的补货时间并承担相应的库存持有成本和延迟惩罚成本。文章同时建立了供应商之间的纳什博弈模型和以制造商为主方的主从博弈模型,以找到供应商的最佳供货时间和制造商最优的库存承担时限。通过对比不同模式下供应链的整体绩效,找到实现供应链协调运作的必要条件,并通过数据分析进一步证明相关结论。     

预测精度和成本双时变的短生命周期产品供应链优化与协调

对于提前期可压缩的短生命周期产品供应链,压缩提前期可以提高销售商的需求预测精度,但增加了制造商的生产成本,因而供应链面临何时订货、订多少,以及如何实现Pareto改进的挑战。通过建立数学模型并求解,分析了分散系统和集中系统的最优决策,进一步开发了一个激励方案以实现供应链成员之间的协调。研究结果表明:具有订货回馈与惩罚的动态批发价契约能够有效协调双时变参数供应链,契约参数α在一定范围内取值可实现供需双方共赢。     

What is the impact of sustainable development on the re-localisation of manufacturing enterprises?

Rendering the supply chain more eco-friendly is an innovative idea progressively adopted by industry. Our research focuses on the CO₂ equivalent emissions along the supply chain due to freight energy use and storage. A supply chain model based on discrete event simulation was developed. The model uses reorder point production management policy (ROP) within a make to stock (MTS) demand response strategy. Manufacturing capability is also taken into account using an overall equipment effectiveness indicator (OEE). In addition, the location of the firms and their types of products are modelled. The purpose is to compare supply chain CO₂ equivalent emissions of different configurations. This method is applied to two industrial cases: Carrier (UTC group), a large cooler manufacturer and Zannier group, a textile industry. The principle objective of the study is to conduct pertinent experiments to give green guidelines to Carrier and Zannier group.     

Penalty and financial assistance in a supply chain with supply disruption

In a supply chain, when the supply is hit by an unexpected disruption, the supplier may face certain financial difficulty to resume normal production, causing a supply shortage as well as a loss to the manufacturer and the entire supply chain. Combining a penalty term in writing contracts with the provision of financial assistance is the “carrot and stick” approach used by a manufacturer to deal with supply disruption. This article investigates how the manufacturer, in a better financial situation, may use ex-ante penalty terms and ex-post financial assistance to compel the supplier to recover its production capability as much as possible. We find that, the MS (integration of financial assistance and the non-delivery penalty) is the best strategy for the manufacturer in most situations, but it is not a win–win strategy. An interesting result contrary to the conventional wisdom, is that the optimal delivery quantity for the supply chain under the centralized decision-making is less than that under the decentralized decision-making.     

供需不确定下基于MOI和VMI模式的供应链协同比较研究

为分析供应链运作机制对降低随机供应商产出和随机需求的影响,对比研究了两供应商-单制造商系统在MOI和VMI两种模式下的供应链协同模型。MOI模式下,制造商管理并持有库存,提出了供应风险共享的协同机制;VMI模式下,供应商管理并持有库存,提出了收益共享与额外惩罚的协同机制。分析了集中决策、MOI和VMI模式下的最优批量决策,证明了VMI模式下存在唯一的纳什均衡。研究还发现,VMI模式更容易协调供应链,有效降低供需不确定的影响。MOI模式下的供应链可实现帕累托改进,但不能实现协调;而当参数满足一定关系时,VMI模式下供应链的期望利润可达到集中决策。     

Strategic inventory deployment for retail and e-tail stores

In this paper, we study a supply chain comprising one manufacturer and one retailer. Customers can make purchases either from the retailer or directly from the manufacturer via an e-tail channel. From the manufacturer's perspective of managing the two channels, we study three different inventory strategies, namely centralized inventory strategy, a Stackelberg inventory strategy, and a strategy where the e-tail operation is outsourced to a third party logistics provider (3PL). For each strategy, we obtain the optimal inventory levels in retail and e-tail stores and the respective expected profits. We compare the performance of various strategies. Managerial insights are provided through analytical and numerical analyses to illustrate the applicability of different strategies.     

供应链中的批量与信用期联合决策研究

信用支付契约是使供应链各方达到协调的重要手段。本文在单个制造商和单个零售商组成的两级供应链系统下,建立了制造商和零售商的库存控制模型,提出了联合决策零售商的订货批量,以及制造商的生产批量和定期信用支付期的启发式算法。给出了利润分配方案,以使供应链达到协调。最后,本文通过算例验证了模型和算法的有效性,为运用信用支付契约协调供应链提供了理论依据。     

The Impact of Modular Assembly on Supply Chain Efficiency

This article studies the impact of modular assembly on supply chain efficiency. In the modular assembly approach, a manufacturer acquires pre‐assembled modules from its suppliers, rather than the individual components, as in the traditional assembly approach. We analyze the competitive behavior of a two‐stage modular assembly system consisting of a manufacturer, and a supplier who pre‐assembles two components into a module. The firms can choose their own inventory policies and we show the existence of Nash equilibrium in the inventory game. Moving from the traditional to the modular approach has a twofold effect on the supply chain. First, we investigate the effect of centralizing the component suppliers. It can be shown that when there is no production time shift, the module supplier always holds more component inventories than suppliers do in the traditional approach, which yields a lower cost for the manufacturer. However, the suppliers, and therefore the supply chain may incur a higher cost in the modular approach. Second, we study the effect of a shift in production time from the manufacturing stage to the supplier stage. From numerical studies, it has been found that such a lead time shift always benefits a centralized supply chain, but not necessarily so for a decentralized system. Combining the two effects, we find that the modular approach generally reduces the cost to the manufacturer and the supply chain, which explains the prevalence of modular assembly from the perspective of inventory management. These results also provide some insight into how firms can improve supply chain efficiency by choosing the right decision structure and lead time configuration.     

Interorganizational Collaborative Forecasting and Replenishment Systems and Supply Chain Implications

Collaborative Forecasting and Replenishment (CFAR) is a new interorganizational system that enables retailers and manufacturers to forecast demand and schedule production jointly. The capabilities of CFAR exceed those of the traditional EDI because CFAR allows exchange of complex decision support models and manufacturer/retailer strategies. The proponents of CFAR claim that the fastest way for retailers and manufacturers to slash inventory costs and product shortages is by coordinating their decisions. The impact of CFAR on the supply chain using a model consisting of a manufacturer selling its product through two independent identical retailers is analyzed. The model assumes that the manufacturer doesn't face capacity constraints, the demand is stationary, and retailer prices are constant over time; the shortages are backordered at the manufacturer and retailers to isolate the effects of information sharing in CFAR. The most significant findings relate to the increase in the cost incurred by the nonparticipant in CFAR, the increase in the manufacturer's cost of serving the nonparticipant if the participant can obtain delivery guarantees in return for demand information sharing, and the incentives of the players to move towards universal retailer participation in CFAR. The findings are explained using the risk structure faced by the players in the supply chain. The managerial implications of the impact of CFAR on the supply chain structure are also discussed.     

Inventory routing problems in a context of vendor-managed inventory system with consignment stock and transshipment

The inventory routing problem involves the integration and the coordination of two components of the logistics value chain: the inventory management and the vehicle routing decisions. In fact, the aim is to jointly decide on the distribution tour, from a distribution centre to a set of locations, and on the inventory policy for each location. Although many research investigations show great interest in policies such as transshipment or dynamic routings on the distribution system performances, these approaches are often criticised in practice as being too restrictive. In this article, we consider the inventory routing framework in a supplier integration context, i.e. a vendor-managed inventory with a consignment stock policy. Under such framework, we show that the transshipment brings more benefits than the classical context. In particular, we consider the case of static routings and we numerically show that transshipment permits to better optimise the distribution tours and to improve the global performance of the supply network.     

A comparative study of formulations for a cross-dock door assignment problem

A cross docking facility is a type of warehouse in supply chain management that allows orders to be prepared with or without going through the phase of storing products in the warehouse and subsequently selecting them for delivery. The goods are unloaded from incoming trucks called origins on inbound doors of a cross-docking facility platform and, using a handling device inside the platform such as a forklift, immediately transferred to outbound doors to be loaded into outgoing trucks named destinations or delivery trucks for distribution to customers. Contrary to a traditional warehouse, goods are unloaded and loaded without placing them in temporary storage inside the cross-docking facility. The goal of the cross-docking assignment problem (CDAP) is to assign origins to inbound doors and destinations to outbound doors so that the total cost inside the cross-dock platform is minimized. To the best of our knowledge, there are only three mixed integer programming (MIP) formulations of the CDAP in the literature. We propose eight new MIP models and demonstrate the mathematical equivalence of all 11 models, together with rigorously proving some of their properties. In order to detect which of these 11 models is best, we conduct an extensive comparative analysis on benchmark instances from the literature, which discloses that the best model is one proposed in this paper for the first time.     

具有时变运输时间的JIT系统批量决策

本文的研究对象是由制造商、配送中心和零售商组成的多级供应链系统,其中零售商要求制造商为其提供短时间间隔、小批量的JIT配送。研究内容为在时变运输时间影响下的供应链系统批量决策问题。在实际运输时间数据的基础上建立了时变运输时间的函数,并以此构建了系统的总成本函数,并在相关文献研究的基础上采用新的更为有效搜索规则进行了求解。根据求解规则,采用ActiveX自动化技术将Matlab的数值计算功能嵌入Visual Basic的集成开发环境中,开发了对应的决策支持系统。最后进行了敏感性分析并提供了低运作成本的决策支持方案。     

Channel Coordination for a Supply Chain with a Risk‐Neutral Manufacturer and a Loss‐Averse Retailer*

This articles considers a decentralized supply chain in which a single manufacturer is selling a perishable product to a single retailer facing uncertain demand. It differs from traditional supply chain contract models in two ways. First, while traditional supply chain models are based on risk neutrality, this article takes the viewpoint of behavioral principal–agency theory and assumes the manufacturer is risk neutral and the retailer is loss averse. Second, while gain/loss (GL) sharing is common in practice, there is a lack of analysis of GL‐sharing contracts in the supply chain contract literature. This article investigates the role of a GL‐sharing provision for mitigating the loss‐aversion effect, which drives down the retailer order quantity and total supply chain profit. We analyze contracts that include GL‐sharing‐and‐buyback (GLB) credit provisions as well as the special cases of GL contracts and buyback contracts. Our analytical and numerical results lend insight into how a manufacturer can design a contract to improve total supply chain, manufacturer, and retailer performance. In particular, we show that there exists a special class of distribution‐free GLB contracts that can coordinate the supply chain and arbitrarily allocate the expected supply chain profit between the manufacturer and retailer; in contrast with other contracts, the parameter values for contracts in this class do not depend on the probability distribution of market demand. This feature is meaningful in practice because (i) the probability distribution of demand faced by a retailer is typically unknown by the manufacturer and (ii) a manufacturer can offer the same contract to multiple noncompeting retailers that differ by demand distribution and still coordinate the supply chains.     

基于新产品的供应链最优生产策略

商业竞争与技术进步导致产品生命周期的缩短,要求企业能不断地推出新产品。而新产品的生产与需求是一个逐步适应和熟悉的过程,具有明显的学习效应。本文运用Bass模型来描述新产品的需求扩散效应,建立了新产品供、产、销三级供应链的生产存储优化模型,并通过算例,计算机模拟出最优生产批量。该研究改进了传统的一般产品的生产存储计划,对面向市场需求的供应链的新产品投产具有重要的指导意义。     

政府规制下非对称信息对闭环供应链差别定价的影响研究

为了研究政府规制下非对称信息对闭环供应链（CLSC）差别定价的影响，构建了政府、制造商、零售商和消费者的三阶段博弈决策模型，通过分析政府补贴与惩罚政策下CLSC各利益主体的最优定价策略，发现：在政府规制的最优水平下，非对称信息的单位产品的外部性成本变化对制造商的利润影响更为显著；新产品和再造品间的替代率存在界点，对不同决策下零售商产品定价影响不同；社会福利是政府规制的联合凹凸函数，政府的奖惩政策存在最优水平，提高了政府的规制水平，对制造商提高生产工艺和回收水平起到积极促进作用。     

基于RFID技术的供应链投资决策及协调策略研究

本文以单制造商和单零售商组成的两级供应链为研究对象,基于链上成员是否投资RFID技术,考虑四种情景:供应链成员均不投资RFID,仅零售商投资RFID,仅生产商投资RFID及供应链成员共同投资RFID。采用Newsvendor模型建立四种情景时链上成员的收益模型,得出Stackelberg均衡解和供应链成员的最优期望收益,探讨了RFID技术投资对各情景时链上成员收益的影响,得到了供应链成员共同投资RFID时的协调策略。研究表明:当RFID标签成本和零售商库存不准确率在相应的阈值内,零售商或制造商单独投资RFID技术均能提升自身收益,同时对链上其他成员的收益存在"正外部性";此外,收益共享契约能够有效地协调链上成员共同投资RFID技术后的供应链,并且该协调思想丰富并拓展了供应链投资RFID技术的协调研究。     

农产品冷链三级库存一体化策略研究

本文建立了有限期内一个生产商、多个分销商、多个零售商的一体化库存模型,研究了需求率为时变函数、产品价格既定、系统利润最大情况下,供应链上各成员的最佳订购策略。本文以指数需求率为例,证实一体化决策的系统利润大于零售商主导的非一体化决策,然而,一体化决策并非对所有供应链成员有利。本文最后提出了协调供应链各成员利润的分配机制,从而确保一体化决策的有效实施。     

带学习效应的双渠道供应链库存策略研究

针对具有学习行为的双渠道供应链问题,本文研究了两种分销渠道并存下的最优库存策略。有限计划期内,分销商通过传统销售和在线销售来满足下游顾客的需求。两种分销渠道下的销售单价为时变不减线性函数,当系统中各周期的生产订购固定成本以一定的概率具有学习效应行为时,分别建立了非变质产品生产存贮问题的混合整数约束优化模型以及易变质产品存贮问题的无约束混合整数优化模型,所建立模型的目标为极大化分销商总利润函数。对于这两类模型,通过分析其最优解的性质,利用将生产订购次数松弛为连续变量的技巧证明了最优解存在的唯一性。给出了最优策略的求解方法并比较了两类模型最优利润函数值的大小。最后通过数值算例对上述模型进行了验证,数值结果表明当供应链系统中存在学习效应行为时,该系统能够获得更多的利润。