随机需求下供应商管理库存的供应链模型

以一个供应商和一个零售商的两阶段供应链为背景,利用报童模型给出了供应商管理库存(VMI)的供应链模型,在需求服从均匀分布的条件下得出解析解,并与传统的零售商管理库存(RMI)系统作了比较,分析了这两种情况下批发价和订货量的变化.数值结果表明VMI导致了批发价的缩减,但提高了订货量,VMI减轻了双重边际效应,系统利润多于传统的RMI系统.     

考虑横向整合战略的库存路径动态区域定价

库存路径和定价是供货商管理库存(Vendor Management Inventory, VMI)中三个互相制约和影响的决策问题,是降低供货商成本,提高其利润的关键。针对VMI拉式供应链中多供货商、多商品和多区域的库存路径定价问题,提出了对不同区域客户、在不同时段进行商品差异化定价策略,并设计一种共同配送车辆司机成本和燃油成本分摊方案,据此构建基于横向整合战略的库存路径动态区域定价模型。算例结果显示,在横向整合战略下,供货商商品定价会有所降低,配送车辆行驶距离显著缩短,各时段配货量更为均衡,期末库存数量显著降低。研究表明,无论供货商之间供货规模比例差异多大,开展库存路径动态区域定价,供货商联盟成员的利润均能得到显著提高,实现合作共赢的目标。     

基于IGA的供应链库存成本优化研究

随着市场竞争的加剧,企业之间的竞争已经演变为了供应链之间的竞争.传统的库存管理主要侧重于单个企业的库存最优,而供应链环境下的库存管理需要最大程度地实现供应链的库存整体最优.本文分析了供应链环境下的库存成本结构和供应链内成本,在此基础上,建立了多个供应商、一个核心制造企业、多个分销商的供应链库存成本模型,在分析免疫遗传算法(IGA)原理的基础上,详细说明基于免疫遗传算法的供应链库存成本模型的求解方法,最后通过算例仿真验证了模型和算法的可行性和有效性.     

基于系统动力学的多客户供应链库存控制研究

为了研究客户目标库存量变化以及订单方式调整对贸易商供应链库存控制的影响,构建多客户供应链系统动力学模型.在局部信息共享条件下,定量的比较了目标库存量变化对贸易商供应链库存的影响;改变参数设置,模拟了在订单方式调整下供应链库存的波动性.结果表明,客户目标库存量的增加降低贸易商供应链成本;全年订单量给定条件下的多频次小批量订单方式加强供应链库存系统稳定性.     

VMI策略下的综合生产计划研究

本重点研究了在供应链环境下，基于供应商管理客户库存(VMI)策略的供应商综合生产计划问题。模型综合考虑了供应链的存储费用、缺货损失和生产费用，提出供应链总成本最小目标模型，并采用搜索法结合线性规划给出了算例求解和分析结论。     

基于两层供应链的VMI系统可行性分析研究

一般来说，供应商管理用户库存（VMI）能够给购买方带来更高的利润，而对供货方的影响却是不确定的。而现实中很多VMI策略都是由购买方主导的，购买方一般不愿和供货方分享收益，因此供货方必须自己判断是否接受VMI策略。本文在基于对安徽奇瑞汽车集团的零部件库存进行的调查的基础上，对VMI系统可行性分析的研究分两步进行：（1）假设供货方已经接受了购买方主导的VMI策略，它如何制定自己的最优送货策略；（2）通过比较供货方分别在RMI和VMI下的最小成本，供货方决定是否接受购买方主导的VMI策略。     

一种考虑广告费对需求影响的供应商管理库存集成模型

降低供应链中处于不同阶段的物料(原材料、在制品以及成品)的库存水平已经成为供应链管理的研究焦点之一。其中供应商管理的库存VMI(vendor-managed-inventory)策略不论在理论上还是在不同企业的实践中都到了广泛的关注。本文首先给出了一个考虑一个供应商和多个不同的订货商,订货商有共同的订货补充期,并且考虑广告费对需求影响的VMI集成模型;其次,给出了模型的相应算法;最后,给出了算例加以说明。     

安全因子优化与协调模型研究

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 .     

外部市场存在替代产品的VMI系统研究

供应商管理用户库存(VMI)作为一种有效的补货机制,能对购买渠道的需求信息做出积极正确的反应.现在对VMI的研究往往集中于单个零售商和单个供应商组成的系统,不考虑VMI系统受市场上其他零售商或供应商的影响.假设市场上多个零售商出售相互之间可替代的产品,某个零售商与其供应商之间应用VMI系统.我们的研究主要有两方面:1)VMI系统是否有助于零售商和供应商组成的供应链在差异产品市场上获得更大的收益;2)供应商和零售商如何决策是否应用VMI系统。     

基于系统动力学的供应链库存策略仿真研究

针对一个动态、多级的供应链库存系统,应用系统动力学的方法,建立了供应链(s,S)库存策略下的物流成本模型,并通过动态仿真,分析了库存策略的变动对于供应链库存系统各级成员间库存供需的动态行为,提出了(s,S)策略下的供应链库存系统的有效管理方法.     

Price markdown scheme in a multi-echelon supply chain in a high-tech industry

This paper studies the price markdown scheme in a supply chain that consists of a supplier, a contract manufacturer (CM), and a buyer (retailer). The buyer subcontracts the production of the final product to the CM. The CM buys the components from the supplier and charges the buyer a service fee for the final product produced. The price markdown is made possible by the supplier with the development of new manufacturing technologies that reduce the production cost for the sourced component. Consequently, the buyer adjusts the retail price in order to possibly stimulate stronger demand that may benefit both the supplier and the buyer. Under this scenario, we identify the optimal discount pricing strategies, capacity reservation, and the stocking policies for the supplier and the buyer. We also investigate the optimal inventory decision for the CM to cope with the price discount by considering both demand and delivery uncertainties. Our results suggest that higher production cost accelerates the effects of higher price sensitivity on lowering the optimal capacity and stocking policies in the supply chain. The effect of mean demand error on the optimal prices is relatively marginal compared with that from price sensitivity. We also found that increasing the standard deviation of the random demand does not necessarily increase the stocking level as one would predict. The results show that delivery uncertainty plays an important role in the inventory carried beyond the price break. We discuss potential extensions for future research.     

提前期需求为模糊随机条件下的连续库存补货策略

考虑提前期内需求为模糊随机变量且提前期为可缩短情形下,建立由购买商和供应商所组成的简单供应链连续库存补货策略优化模型,其中订单量、再订货点和提前期为决策变量.首先推导出模糊随机需求条件下购买商和供应链的成本函数,然后,进一步考虑总需求为三角模糊数,推导出供应商、购买商和供应链的模糊成本函数.在此基础上分别从购买商成本最小和供应链成本最小角度对模型进行求解,结合具体算例对模型进行应用分析和比较分析,结果表明模型具有有效性和实用性,并得出如下结论:从购买商本身角度考虑订购策略所产生的供应链成本总是大于从供应链整体角度考虑订货策略所产生的供应链成本,同时从购买商本身角度考虑订货策略所产生的最优订购量、购买商成本低于从供应链整体角度考虑订货策略所产生的最优订购量、购买商成本.     

Optimal business policies for a supplier–transporter–buyer channel with a price-sensitive demand

As the third party logistics partners (carriers) taking a more and more significant role in supply chain practices and customer service performance improvement, there is an emerging need for the studies on optimal channel coordination policies for business processes involving not only supplier and buyer (retailer), but also transportation partners. In this paper, we explicitly add a transportation partner with concave cost functions into the analysis for supplier–buyer channel coordination policies, and analyse the impact of coordination and pricing policies on supply chain profitability. The market demand is assumed to be a decreasing convex function of buyer's selling price (x), D(x)=d/x². Under this assumption, we quantify the improvement on total supply chain profitability when moving from a non-cooperative environment to a fully cooperative environment, and show that the joint annual profit of three partners in a cooperative environment can be at least twice of what may be achieved by three independently operated companies in a leader–follower business game. While in a real-world business environment, a perfect collaboration is hard to achieve, this result can be used to provide a quick estimation on the upper bound on the budget for profit sharing or discount offers among the supply chain partners.     

Buyer-supplier currency exchange rate flexibility contracts in global supply chains

This paper analyzes a decentralized global supply chain under a newsvendor setting, where a supplier delivers a certain quantity of a single product to a buyer in accordance with the terms of a mutually agreed upon contract. This contract is signed prior to the delivery of the product and subsequent payment, thus, exposing the supply chain to the risk of currency exchange rate fluctuations. We propose two types of currency exchange rate flexibility contracts to explore the characteristics of exchange rate risk mitigation policies for the buyer and the supplier. Furthermore, we investigate the effects of the contract structures on the optimal order quantity, as well as the expected profits of both supply chain members. Our results show that the optimal order quantity of the buyer decreases when the wholesale price is uncertain due to exchange rate volatility. Also, both our proposed contracts tend to improve the expected profits of both the buyer and the supplier, when the payment is made in the supplier’s currency, indicating the desirability of adopting such contractual agreements from the perspective of both parties. On the other hand, when the payment is made in the buyer’s currency, our suggested contracts do not yield such win-win scenarios. Finally, we examine the effectiveness of availing the services of a local vendor, which is capable of satisfying any demand in excess of the quantity ordered from the foreign source with short notice, in order to mitigate the risks associated with an overseas order.     

坏账和延期支付策略下采购商最优订货模型

在供应商、采购商及其顾客组成的三级供应链结构中,供应商提供给采购商较长的延期支付期限,采购商提供给其顾客较短的延期支付期限。且由于顾客为不特定多数,存在一定的坏账风险。文章从采购商的角度出发,分析在二阶延期支付策略下,坏账影响下采购商的最优订货策略。首先,考虑到坏账会影响采购商的利息收入和利息支出,因此文章从低坏账率和高坏账率两种情形出发,探讨了坏账影响下采购商的利息收入与利息支出,建立了相应的决策模型。其次,通过模型的分析求解,得出采购商的最优订货周期和最优订货批量的判定方法,进一步分析了各参数对采购商最优决策的影响。最后,通过数值分析对有关结论进行了验证,文章的分析研究不仅具有一定的理论意义,而且可以更好地指导采购商的订货决策。     

供应商掺假行为的博弈分析与机制选择

供应商掺假行为会影响产品最终的质量与安全。本文研究由一个供应商和一个买方组成的分散式供应链,建立以买方为领导者的Stackelberg博弈模型,比较研究延期付款机制、检查机制与溯源机制对供应商掺假行为的影响。研究表明,检查机制与溯源机制无法完全阻止供应商的掺假行为,而延期付款机制可以实现对供应商掺假行为的完全遏制,其中生产掺假产品与非掺假产品的成本差是影响三种机制效率的重要因素。此外,增加买方产品责任成本可以有效降低供应商的掺假意愿,而供应商与买方的融资利率差会增加为防止供应商掺假行为的供应链成本,通过降低检查成本与溯源成本可以促使买方更好地遏制供应商的掺假行为。最后给出算例验证了上述结论,并进一步分析了各机制中不同参数对最优决策和利润的影响。     

Endogenous information acquisition in supply chain management

In this paper, we analyze an endogenous determination of efforts put into information acquisition and its impact on supply chain management. More specifically, we consider a supplier who sells a product to a buyer during a single selling season. Prior to placing an order with the supplier, the buyer has an option to acquire additional information about the demand by hiring experts (who are capable of providing forecasts). Because a commission fee must be paid to each hired expert, there exists a tradeoff between the cost and the value of the information, and the buyer needs to determine how much information to acquire. We derive the optimal information-acquisition level in an integrated setting and compare it with that determined in a decentralized setting. We also analyze several types of supply contracts to examine if they can coordinate the supply chain and allow an arbitrary division of system profit between the supplier and the buyer.