闭环供应链下再制造生产计划研究述评

再制造是实现循环经济"减量化、再利用、资源化"三原则的重要途径。再制造生产活动中,计划扮演着重要的先行角色。本文根据再制造系统的回收和拆卸特色,先讨论与再制造生产计划有关的几个重要参数;然后从再制造生产计划的结构层次入手,对再制造生产计划领域的研究进展进行探析;最后指出目前研究不足之处以及未来研究的可能方向。     

绿色再制造运作模式分析

绿色再制造是实现环境可持续和经济可持续发展目标的一种新生产方法,它不只关注物料的回收,更关注产品的增值回收.但是,不同于传统的大规模生产、精益生产与敏捷制造生产方式,这种生产在产品生命周期、生产理念、资源内涵、空间范围、竞争要素、核心思想、理论基础和生产方式方面存在明显差异.同时,认为绿色再制造的生产计划与控制具有如下的特征"原材料"的可获得性、拆卸工序的难易性、再制造加工路线和加工时间不确定性、综合计划的难编制性和生产计划和控制的动态性.     

考虑质量成本的再制造系统批量计划综合优化

研究需求和再制造率不确定下整个再制造系统的综合协调问题,帮助再制造商制定各环节批量决策以实现整体最优． 首先,考虑对应其拆卸后不同质量状况的差异再制造成本,构建能反映质量成本的拆卸和再制造总成本模型; 接着,考虑新零部件采购提前期,利用两阶段利润函数的思想,构建包括拆卸、再制造和重新装配3个子系统中所有成本因素、以利润最大化为目标的优化模型; 然后,求解最优再制造/拆卸比率、拆卸批量、再制造/采购批量和重新装配批量; 最后,通过算例验证并讨论平均再制造零部件获取成本对再制造批量、采购批量、拆卸和再制造总成本以及总利润的影响,再制造/拆卸比率和单位拆卸成本的关系．     

考虑不同回收质量等级的再制造系统回收生产决策

废旧产品的回收再制造过程往往在回收质量、再制造成本、再制造产出率、再制造产品需求等方面存在不确定性因素,极大地增加了再制造生产管理决策的复杂性。本文在一个回收再制造系统中研究了存在多种回收质量等级时的两阶段回收—再制造联合优化决策问题,并扩展到需求与价格相关和再制造产出率随机两种情形。在最大化再制造商期望利润的决策目标下,基于每种回收质量等级的单位回收和再制造成本构造出再制造系统的有效生产前沿面,给出了不同决策情形下再制造商的最优回收数量、销售定价的解析解,并且分析了一些主要的参数对再制造商最优决策的影响。本文的研究结果表明：（1）含有多种回收质量等级的再制造系统中存在一个下凸的有效生产前沿面,不在该前沿面上的任何质量等级的回收产品都将不会被用于再制造;（2）在同等的政府补贴额度下,回收补贴方式对再制造商决策的影响程度大于再制造补贴方式;（3）当再制造品的市场需求与价格相关时,最优销售价格至少大于第一种被使用的回收质量等级的边际回收和再制造成本;（4）任意两种回收质量等级之间存在着替代或互补效应,由其成本差异决定,并且这种效应随着需求不确定性的增大而增大;（5）再制造产出率的不确定性和再制造品需求的不确定性之间存在"对冲"效应,这种效应随着再制造产出率不确定性的降低而减弱。本文的研究可为不确定性环境下再制造企业的回收、生产管理决策提供有益的管理启示。     

基于机会约束规划的制造/再制造混合系统生产决策

在经济利益和环境效益的双重驱动下,许多原始设备制造商纷纷开始从事再制造活动,其原有的单一制造系统因而转变为制造/再制造混合系统,传统的生产计划面临着一些新的挑战.本文针对制造/再制造混合系统的生产决策问题展开研究,考虑处置策略以及回收和需求的不确定性,建立问题的机会约束规划模型,并设计遗传算法进行模型求解,最后给出了算例验证其有效性.     

第三方回收商领导型两级闭环供应链的回收与定价策略

与一般废旧产品的回收产品再制造相比,废弃电子电器产品回收拆解后需要兼顾产品与零部件再制造,从而减少电子电器产品对环境的污染,推进资源的重复利用。为了探讨第三方回收商的回收与定价策略对供应商和制造商的影响,本文构建由单一供应商、制造商和第三方回收商组成的两级再制造闭环供应链,建立Stackelberg博弈模型,研究两级再制造情形下和仅产品再制造情形下回收商的有效回收比例、回收定价和回收努力程度等决策,并对两种再制造情形下供应链各成员的决策与收益进行对比分析。研究发现：对于回收商而言,回收数量、有效回收比例的增加有助于回收商获得更多的额外收益。如果在仅产品再制造情形下的有效回收比例较大,回收商的决策和收益主要取决于无效零部件的回收价。当无效零部件的回收价较低时,回收商在仅产品再制造情形下的决策和收益更优;反之,回收商在两级再制造情形下的决策和收益更优。对于其他供应链成员而言,两种再制造策略都能够降低供应商和制造商的定价,促进市场需求的增加。具体而言,不同的再制造策略对批发价、零售价和市场需求的影响与有效回收比例和无效零部件的回收价密切相关。     

专利保护下再制造闭环供应链协调机制研究

受专利保护的原制造商享有产品再制造的专有权利,只有获得原制造商的专利许可,第三方再制造商才能进行专利产品的回收再制造.针对再制造知识产权保护在管理研究中的不足,本文建立了受专利保护的原制造商许可第三方再制造的闭环供应链模型,利用博弈理论讨论了分散与集中情况下节点企业的最优决策.同时,分析了专利许可对旧产品回收再制造的影...     

考虑产品可替换的再制造产品选择决策

再制造是处理回收产品的一种重要方式.本文研究了一种简单的产品可替换的再制造决策模型,再制造商生产的产品有高质量和低质量两种,高质量的再制造产品数量超过需求量时,可以作为低质量产品的替换品销售.最后通过仿真算例说明了产品可替换策略比不可替换具有优势.     

奖惩机制下具竞争制造商的废旧产品回收决策模型

各国政府为保护环境加强了对废旧电器电子产品的回收再制造的管制。本文研究了两个制造商竞争情况下基于政府奖惩机制的制造商的废旧产品回收决策问题。具体研究时分两种情况:一种情况是两个制造商中只有一个回收再制造废旧产品,另一种情况是两个制造商都回收再制造废旧产品。研究表明:奖惩机制下回收再制造废旧产品的制造商的回收率提高;无论制造商是否回收再制造废旧产品,其新产品销售价均比无奖惩机制时低,奖惩机制对消费者有利;制造商竞争有利于奖惩机制引导制造商提高废旧产品的回收率;回收率随再制造率的提高而提高;无论另一个制造商回收再制造废旧产品与否,实施回收再制造制造商的利润随奖惩力度的提高而增加,随政府规定的目标回收率的提高而降低,且奖惩力度越大,降低幅度越明显。算例分析说明了上述结论的正确性。     

创业团队共享领导对企业创新绩效的影响机制

在第三方再制造商参与废旧产品的回收再制造活动时,往往会涉及专利许可与政府规制问题.构建了制造商与再制造商之间的动态博弈模型,分别探讨了无专利许可无政府规制、有专利许可无政府规制、有专利许可有政府规制3种模式下企业的生产决策和再制造绩效水平.研究发现,以制造商主导的专利许可机制对再制造活动具有一定的抑制作用,仅当再制造产业发展较为成熟时才能为制造商带来显著收益;以政府主导的生产者责任延伸制度有利于促进再制造产业发展,尤其在再制造业发展初期可有效提升产品回收再制造率,并且该制度对再制造的促进作用与再制造带来的环境效益呈正相关.研究结论对专利产品再制造过程中各企业的生产策略选择以及政府在再制造产业发展各阶段中财政政策的制定具有一定的参考价值.     

Development and analysis of mathematical and simulation models of decision-making tools for remanufacturing

This article presents decision-making tools for remanufacturing. The first decision-making tool was used to address inventory lot-sizing problems in a hybrid remanufacturing–manufacturing system with varying remanufacturing fraction. In this article, the new inventory lot-sizing model with variable remanufacturing lot sizes has been shown to exhibit better performance than the benchmark model with fixed remanufacturing lot sizes. The new inventory lot-sizing model is anticipated to become a valuable decision-making tool in companies that are planning to adopt remanufacturing. The second decision-making tool was applied to address a production and inventory planning problem in a remanufacturing system considering different remanufacturing policies for a given remanufacturing strategy. For a remanufacture-to-stock system with two quality remanufacturables groups four alternative policies were examined, a policy which specifies simultaneous processing utilising dedicated resources was shown to be the best policy to achieve a shorter remanufacturing cycle time. For a remanufacture-to-order system with two quality remanufacturables groups, the three relevant policies of the four alternative policies were examined, a policy which specifies sequential processing and switching between various quality remanufacturables groups was shown to be the best policy to achieve a shorter remanufacturing cycle time. The production and inventory planning simulation models in a remanufacturing system are expected to become significant decision-making tools in remanufacturing operations.     

Production planning and control for remanufacturing: literature review and analysis

This article reviews the literature on production planning and control (PPC) for remanufacturing. The objectives are threefold: to determine whether the gaps identified by Guide (Guide Jr, V.D.R., 2000. Production planning and control for remanufacturing: industry practice and research needs. Journal of Operations Management, 18, 467–483) on the subject with respect to the main complicating characteristics of remanufacturing have been fulfilled; to classify the literature based on an appropriate structure to obtain a better understanding of the subject identifying sources of future research and to provide a useful source for scholars and practitioners. Seventy-six papers were examined and classified. It was found that none of the studies deals simultaneously with all of the complicating characteristics, and that more practical research is needed. In addition it was found that we lack studies regarding forecasting and aggregate planning considering disassembly of returned products, material matching restrictions or stochastic routings, master production scheduling considering material matching restrictions or stochastic routings, ordering system and capacity planning considering material matching restrictions and inventory control and management considering stochastic routings.     

The Impact of Product Lifecycle on Capacity Planning of Closed‐Loop Supply Chains with Remanufacturing

Product recovery operations in reverse supply chains face rapidly changing demand due to the increasing number of product offerings with reduced lifecycles. Therefore, capacity planning becomes a strategic issue of major importance for the profitability of closed‐loop supply chains. This work studies a closed‐loop supply chain with remanufacturing and presents dynamic capacity planning policies developed through the methodology of System Dynamics. The key issue of the paper is how the lifecycles and return patterns of various products affect the optimal policies regarding expansion and contraction of collection and remanufacturing capacities. The model can be used to identify effective policies, to conduct various “what‐if” analyses, and to answer questions about the long‐term profitability of reverse supply chains with remanufacturing. The results of numerical examples with quite different lifecycle and return patterns show how the optimal collection expansion/contraction and remanufacturing contraction policies depend on the lifecycle type and the average usage time of the product, while the remanufacturing capacity expansion policy is not significantly affected by these factors. The results also show that the collection and remanufacturing capacity policies are insensitive to the total product demand. The insensitivity of the optimal policies to total demand is a particularly appealing feature of the proposed model, given the difficulty in obtaining accurate demand forecasts.     

Remanufacturing of mobile phones—capacity, program and facility adaptation planning

Successful remanufacturing of mobile phones must meet the challenges of continuously falling prices for new phone models, short life cycles, disassembly of unfriendly designs and prohibiting transport, labor and machining costs in high-wage countries. A generic remanufacturing plan for mobile phones is developed. For the planning of remanufacturing capacities and production programs, a linear optimization model is introduced. To support the planner in the periodic adaptation of an existing remanufacturing facility under quickly changing product, process, and market constraints, discrete-event simulation is applied. Uncertainties regarding quantity and conditions of mobile phones, reliability of capacities, processing times, and demand are considered. The simulation model is generated by an algorithm using results from the linear optimization approach.     

Production planning and control for remanufacturing: exploring characteristics and difficulties with case studies

Production planning and control for remanufacturing is a major managerial challenge in the operations management. Researches demonstrate the need for decision-making methods in this context, which has generated theoretical and quantitative studies. However, this area still lacks empirical studies dealing with the practical, day-to-day difficulties of remanufacturers. The purpose of this paper is to link the literature and practice in a systematic in such a way that it is possible to show the similarities and differences between theoretically listed needs and real cases, thereby extending the results of previous research. For this purpose, four case studies are considered. The cases involve original equipment manufacturers (OEM) of automotive parts that have remanufacturing operations. The results indicate that these companies have difficulties that have not been addressed to date in the literature related to the uncertainties inherent in remanufacturing. In addition, we find that these companies use simplified decision-making approaches.     

The Value of Quality Grading in Remanufacturing

In this paper we consider a tactical production‐planning problem for remanufacturing when returns have different quality levels. Remanufacturing cost increases as the quality level decreases, and any unused returns may be salvaged at a value that increases with their quality level. Decision variables include the amount to remanufacture each period for each return quality level and the amount of inventory to carry over for future periods for both returns (unremanufactured), and finished remanufactured products. Our model is grounded with data collected at Pitney‐Bowes from their mailing systems remanufacturing operations. We derive some analytic properties for the optimal solution in the general case, and provide a simple greedy heuristic to computing the optimal solution in the case of deterministic returns and demand. Under mild assumptions, we find that the firm always remanufactures the exact demand in each period. We also study the value of a nominal quality‐grading system in planning production. Based on common industry parameters, we analyze, via a numerical study, the increase in profits observed by the firm if it maintains separate inventories for each quality grade. The results show that a grading system increases profit by an average of 4% over a wide range of parameter values commonly found in the remanufacturing industry; this number increases as the returns volume increases. We also numerically explore the case where there are capacity constraints and find the average improvement of a grading system remains around 4%.     

Rough-cut capacity planning for remanufacturing firms

Capacity planning is a critical element of any successful production planning and control system. A method of rough-cut capacity planning is developed, based on the bill-of-resources approach, that can be used to plan for capacity required for firms in a remanufacturing including overhaul repair operations environment. The modified bill-of-resources approach developed takes into account two major stochastic elements inherent in this environment; probabilistic material replacement factors and probabilistic routing files. A detailed example from an actual repair overhaul operation is presented to illustrate the technique.     

基于改进策略的混合型制造/再制造系统分析

在制造和再制造并存的混合型系统中,制造商需要同时协调新产品生产过程和旧产品再制造过程,这种双向物流的集成运作使得传统的生产规划和库存管理方式不再适用,如何构建一种有效的控制策略来协调生产过程和再制造过程就显得十分关键。本文在优化库存信息的基础上提出了一种适用于混合系统的改进策略,同时考虑到系统复杂性,主要采用控制理论中的传递函数技术构建了系统模型。仿真结果表明,本文提出的改进策略不仅可以有效协调新产品生产过程和旧产品再制造过程,而且还可以显著改善系统性能。     

Production planning for remanufactured products

This paper presents a methodology for production planning within facilities involved in the remanufacture of products. Remanufacturing refers to the process of accepting inoperable units, salvaging good and repairable components from those units, and then re-assembling good units to be re-issued into service. These types of facilities are common, yet many suffer from the unpredictability of good and repairable component yields, as well as processing time variation. These problems combine to make it extremely difficult to predict whether overall production output will be sufficient to meet demand. Low yields of key components can lead to shortages which require the facility to purchase new components for legacy systems, often with long lead times, thus causing overall delays. The approach developed here is a probabilistic form of standard material requirements planning (MRP), which considers variable yield rates of good, bad, and repairable components that are harvested from incoming units, and probabilistic processing times and yields at each stage of the remanufacturing process. The approach provides estimates of the expected number of remanufactured units to be completed in each future period. In addition, we propose a procedure for generating a component purchase schedule to avoid shortages in periods with a low probability of meeting demand. The proposed methodology is applied to an antenna remanufacturing process at the Naval Surface Warfare Center (NSWC). In this case study the proposed methodology identifies a potential shortage of a key component and suggests a corrective action to avoid significant delay in the delivery of remanufactured units.