不对称信息下考虑供应中断和延期交货的采购合同设计

研究不对称信息下供应商供应中断和延期交货两类风险对制造商采购决策的影响。运用采购机制设计理论与方法,分析了制造商最优采购合同及供应商最优生产决策。结果表明:1)供应商生产数量和交货提前期应分别用中断罚金和延期罚金规制;2)供应商有关供应可靠性的私有信息使高类型供应商的两类罚金均增加,交货提前期缩短;同时,低类型供应商的中断罚金减小,延期罚金和交货提前期不受影响;3)信息不对称不一定降低社会福利。     

基于讨价还价博弈的ATO供应链零部件生产及补货策略

通过建立ATO供应链中最终产品制造商与其两个供应商间的讨价还价合作模型,研究了ATO供应链的零部件生产补货策略和相应的利润分配策略,并探讨了供应链中各合作主体议价能力对最优解的影响。研究发现,ATO供应链应随着最终产品销售价格的提高而增加零部件产量,随最终产品组装成本或零部件生产成本的提高而减少零部件产量;随着最终产品制造商对其中一个供应商议价能力的增强,该供应商零部件的转移价格及其利润会降低,而另外一个供应商的零部件转移价格和利润会提高;若最终产品制造商比另外一个供应商的议价能力强,其期望利润会得到提高,反之,则会降低。     

产能与需求不确定下基于MOI和VMI的供应链比较研究

为分析供应链运作机制对降低产能不确定和需求不确定的影响,对比研究了MOI和VMI两种供应链运作模式下单关键零部件供应商-单制造商组成的两级供应链系统。MOI模式下,制造商负责产品的库存决策,并承担相应的零部件库存成本和缺货成本;VMI模式下,供应商负责产品的库存决策和额外产能储备决策,并承担相应的零部件库存成本和过剩能力闲置成本。给出了供应链的最优解及期望利润;为进一步讨论供应链管理模式对提升供应链运作效率的管理意义,分析了随机需求、随机产能及批发价格对两种模式的影响。     

基于提前期的多周期通用件库存模型

在单一周期库存模型的基础上，建立了多周期的通用件库存模型，对无通用件和有通用件的库存模型进行了比较研究，在模型中重点考虑提前期对通用件库存系统的影响，并以风神汽车有限公司有关数据进行了数据分析，揭示出基于提前期的单一周期模型中得出的结论并不能直接套用到多周期模型中，也就是说采用通用件并不总是能够降低库存水平和成本的，这个结论纠正了理论界认为单一周期库存模型的结论普遍适用的观点；研究基于提前期的通用件库存库存模型也是对通用件库存模型没有考虑提前期影响的一个扩展研究。     

多产品供应商选择的模糊多目标整数规划模型

以成本、质量、交货为目标,考虑供应商供应能力、采购数量、供应数量的柔性、评价等级等约束,建立了多产品供应商选择的模糊多目标规划模型.采用降半梯形分布的隶属度函数将模糊多目标规划模型转化为单目标线性规划并求解,应用算例证明了模型的有效性和可行性.     

MTO生产模式的交货期决策模型及其分析

通过对订单生产模式下产品提前或延期交付所引发的成本分析,以单位产品收益最大为目标构建交货期决策模型,并对模型进行最优性及交货期决策分析.分析结果表明在客户对提前交货没有限制且制造商没有额外成本产生时,承诺交货期应大于平均交货期;延期交付不需支付罚款时,平均交货期是最优的选择;同时考虑产品提前或延期两项成本时,应以平均交货期为基础,结合相关条款综合确定承诺交货期.     

考虑订单合批批量的在线制造商承诺交货期决策研究

承诺交货期策略即向所有顾客承诺一致的交货时间是在线制造商最常用的基于时间的竞争策略。制造商通过调整运营参数来改变交货时间以实现向顾客承诺的交货期。基于运营批量对生产提前期的影响,本文构建了考虑订单合批批量的承诺交货期决策模型,分析了各种参数对生产提前期与运输提前期决策的影响。研究表明,库存成本、单位产品的加工时间、顾客需求的价格敏感性和时间敏感性系数等参数对于在线制造商的生产提前期和运输提前期决策往往具有不同的影响。最后本文的算例验证了研究的结论。     

紧急订单成本信息不对称下的激励契约设计

在正常订单和紧急订单供应商共存情况下.分析制造商的最优订货策略.正常订单供应商采购提前期较长.需在销售期前进行订货.紧急订单供应商交货期较灵活.但交货期长短与成本相关且该成本信息为其私有信息.考虑在此条件下制造商的订货策略(与正常订单供应商)和激励合同设定问题(与紧急订单供应商).最后,比较了紧急订单供应商的存在与否对制造商的订货以及利润的影响.     

基于CVaR准则的供应链协同绿色创新动态优化与协调研究北大核心CSSCI

考虑消费者绿色偏好具有不确定性、产品绿色水平具有动态变化特征的情形,基于CVaR风险度量准则,构建了供应链协同绿色创新的动态优化模型。利用反馈求解法得到不同决策模式下风险规避制造商与风险规避供应商的最优均衡策略,探讨了成员风险规避水平对最优绿色创新策略及供应链绩效的影响。最后,提出双向成本分担契约对供应链进行协调。研究发现：相较于主从博弈,合作博弈下的产品绿色水平及供应链整体绩效水平均有所提高;制造商风险规避行为不利于发展绿色低碳经济,而供应商适度地规避风险可提高供应链整体运作效率;在满足一定条件时,双向成本分担契约的设计与实施能够有效提升产品绿色水平及制造商、供应商和供应链整体的绩效水平。     

基于CVaR准则的供应链协同绿色创新动态优化与协调研究

考虑消费者绿色偏好具有不确定性、产品绿色水平具有动态变化特征的情形,基于CVaR风险度量准则,构建了供应链协同绿色创新的动态优化模型。利用反馈求解法得到不同决策模式下风险规避制造商与风险规避供应商的最优均衡策略,探讨了成员风险规避水平对最优绿色创新策略及供应链绩效的影响。最后,提出双向成本分担契约对供应链进行协调。研究发现:相较于主从博弈,合作博弈下的产品绿色水平及供应链整体绩效水平均有所提高;制造商风险规避行为不利于发展绿色低碳经济,而供应商适度地规避风险可提高供应链整体运作效率;在满足一定条件时,双向成本分担契约的设计与实施能够有效提升产品绿色水平及制造商、供应商和供应链整体的绩效水平。     

基于承诺交货期与价格的通用件库存模型

在对现有文献研究的基础上,从最基本的通用件库存模型出发,引入承诺交货期-价格因素,建立相应的通用件库存模型,研究承诺交货期与产品价格对通用件策略实施效果的影响.通过对无通用件模型、单通用件模型和双通用件模型的比较研究和算例分析,分析了通用件的成本结构对总利润的影响,并且分析了通用件采购成本、单位库存量持有成本以及单位制造费用对于交货期的敏感度在各种情况下对于通用件策略实施效果的影响.分析结论可为企业在各种不同情况的库存策略决策提供有益的指导.     

Switchgear component commonality design based on trade-off analysis among inventory level,delivery lead-time and product performance

The shortening of product delivery lead-times can usually be achieved by keeping high-level components in inventory, however in small-volume production systems, maintaining such inventories is often a costly as well as a risky business strategy. If the risk of maintaining unsold inventory can be decreased, even small-volume manufacturers may be able to justify holding more significant quantities of versatile inventory. This paper discusses a component commonality effect to breakthrough the trade-off relationship between inventory levels and delivery lead-times for such small-volume production systems. By using the same component in different products, inventory maintenance costs can be dramatically reduced, but component commonality design problems are inherently complex, since excessive module commonality may lead to lower product performances, and there are trade-off relationships between product performance and cost reductions obtained through component commonality. In this paper, such a design problem is formulated as a multiobjective component commonality design optimisation problem considering inventory level, delivery lead-time and product performance, and the optimal solutions are obtained as a Pareto optimal solution set. Detailed procedures concerning the proposed design method, including inventory simulation, are discussed and developed for a switchgear design problem. Finally, an example switchgear design problem is solved to illustrate that optimal use of component commonalities across different modules can significantly reduce inventory costs, while also shortening product delivery lead-times.     

On the trade-offs between risk pooling and logistics costs in a multi-plant network with commonality

This paper examines the benefits and costs of two alternative manufacturing network configurations in the presence of component commonality. We evaluate the trade-off between the decreased logistics costs and loss of risk-pooling benefits in plant networks which spread component manufacturing over each plant (product network) as compared to those that consolidate component manufacturing in a single plant (process network). We examine for conditions that mean that a product network would be chosen instead of a process network and vice-versa. We find that the risk-pooling benefit obtained by consolidating common subassembly production is reduced when the cost of acquiring common component capacity is sufficiently high or low. A post-optimality sensitivity analysis for the process network provides insights into subtle substitution effects, which are a direct outcome of cost mix differentials and network structure and complementarity effects, which are induced by the considered sequential assembly system. Our results suggest that the impact of operational cost parameters on strategic decisions can often be non-intuitive. Overall, our analysis provides a link between strategic and operational decision-making in supply chain management, in the context of multi-plant configuration.     

分割配送的生鲜产品库存-路径优化研究

目的 基于供应商管理库存策略,优化协调第三方物流（3rd Party Logistics,3PL）参与的二级供应链系统中库存补充与补货配送的关系,在满足配送需求的同时降低系统的库存和运输成本。方法 综合考虑3PL物流模式下的库存-路径系统中生鲜产品的运输距离、质量时间窗以及需求分割配送策略在时间上的调整等因素,以异质车队车辆行驶燃油成本、车辆调用固定成本、配送超时腐坏成本以及各零售商的库存成本为目标函数,建立多品种生鲜产品库存-路径优化模型。结果 通过改进的遗传算法计算并进行配送量调整优化,得到最终的生鲜配送方案,其系统总成本比配送量调整前减少了9.98%。结论 通过在时间上对配送量进行拆分调整可以有效地节约供应链系统总成本。     

A cost-based methodology for evaluating product platform commonality sourcing decisions with two examples

As more US companies source tooling development and manufacturing overseas in countries like China and Taiwan, are the need and primary drivers for product platforms diminishing? As tooling cost is reduced to a very small percentage of the total project cost, combined with availability of inexpensive purchased components and low labour rates, the need to develop product platforms can decrease substantially. Low cost outsourcing has given firms the ability to develop and manufacture products cheaply without having to spend the additional time and effort to develop product platforms and families. In this paper, two examples involving two consumer product companies and their product lines are presented. Product family components and estimated tooling costs are analyzed, as well as development timing and profit margins to demonstrate why companies are moving away from product platforms in certain types of consumer products. A novel methodology using component commonality decisions relating to major cost drivers is introduced and applied to both examples. Based on the evidence from the examples presented in this paper, there appears to be little financial or functional benefit to develop product platforms that share common components or subsystems when these products are being manufactured offshore; however, even when considering outsourcing, platform-based product development principles can still yield tangible improvements in production costs over the life of the product.     

Product family platform selection using a Pareto front of maximum commonality and strategic modularity

Product family design offers a cost-effective solution for providing a variety of products to meet the needs of diverse markets. At the beginning of product family design, designers must decide what can be shared among the product variants in a family. Optimal design formulations have been developed by researchers to find one optimal component sharing solution based on commonality, cost or technical performance of a product family. However, these optimization methods may not be able to apply in consumer product design because some metrics (e.g., visual appeal and ergonomics) of a consumer product cannot be formulized. In this paper, we suggest a tradeoff between commonality and the quality of the modular architecture in product family platform selection. We introduce a method for designers to identify multiple component sharing options that lie along a Pareto front of maximum commonality and strategic modularity. The component sharing options along the Pareto front can be evaluated, compared, and further modified. We demonstrate the method using a case study of product family platform selection of high-end and low-end impact drivers and electric drills. In the case study, the quality of the modular architecture is evaluated using a design structure matrix (DSM) for each of product variants. Three architectures along the Pareto front with maximum commonality, optimal modularity, and a balanced solution of the two metrics are highlighted and further examined to validate the effectiveness of our method.     

Improving cost effectiveness in an existing product line using component product platforms1

Previously, we introduced a new method for improving commonality in a highly customised, low volume product line using component product platforms. The method provides a bottom-up platform approach to redesign family members originally developed one-at-a-time to meet specific customer requirements. In this paper, we extend the method with an activity-based costing (ABC) model to specifically capture the manufacturing costs in the product line, including the cost associated with implementing a platform strategy. The valve yoke example is revisited in this paper, the customised ABC model is defined, two design strategy alternatives are addressed, and the new method is used to determine which alternative is better at resolving the trade-off between commonality, total cost, and product performance. The proposed method shows promise for creating a product platform portfolio from a set of candidate component platforms that is most cost-effective within an existing product line. The proposed method allows for arbitrary leveraging as it does not rely solely on the traditional vertical, horizontal, or beachhead strategies advocated for the market segmentation grid, and this is especially beneficial when applied to an existing product line that was developed one-at-a-time time such that artefact designs are inconsistent from one to another.     

Component commonality effects on inventory costs

In this paper we study the effects of increasing component commonality for a single-period model. A two-product, two-level configuration under a general component cost structure is considered. The economic implications of replacing different products' components by common components are analyzed. We develop optimal solutions for the Commonality and Non-Commonality (Basic) Models and provide bounds on the total savings resulting from using commonality. We demonstrate, under general and specific component cost structures, that some forms of commonality may not always be a preferred strategy. Furthermore, we present conditions under which commonality should not be used. Finally, an extension to the two-product multicomponent model is provided.     

Simultaneous configuration of platform products and manufacturing supply chains

The product platform concept represents a powerful approach for manufacturers to compete cost-effectively in a global market that requires diverse product range, quick time to market, and rapid responses to supply sources. A key challenge is how to strike a balance between platform commonality and modularity. When a manufacturer outsources its raw materials or module options, the supplier capabilities and production costs should be considered. This paper discusses optimizing decision variables for simultaneously configuring not only platform-based product variants but also their supply chain. We develop a mixed-integer programming model that integrates both platform product design and material purchase decisions based on cost drivers sensitive to commonality and modularity. Theoretical analysis of the model yields two properties, allowing us to further simplify the model and thus help in developing an effective solution algorithm. A numerical example is presented to illustrate how manufacturers strive to dynamically adjust their product design strategies in response to changes in the market demands and/or supply base.     

An integrated inventory model involving manufacturing setup cost reduction in compound Poisson process

The collaboration of vendor and buyer is one of the key factors for successful supply chain management. The most common strategy for a cooperative system is to propose an integrated replenishment plan. Almost all inventory models assume that setup cost is deterministic and is not subject to control. However, in many practical situations, setup cost can be reduced at an added investment. The paper assumes that setup cost can be reduced at an added investment and shortage is permitted during the lead time. This article relaxes the assumption that the demand of lead time is deterministic and is assumed to be a compound Poisson process. A model is derived to determine an optimal integrated inventory policy with controllable setup cost. The expected annual integrated total cost function is derived and a solution procedure is established to find out the optimal solution. Finally, a numerical example is provided to illustrate the solution procedure.