Optimal acquisition price management in a remanufacturing system

Return items received from end customers for remanufacturing is uncertain in nature. In this paper, we considered that return demand function is uncertain and sensitive to the acquisition price and the availability of used products in the market. A mathematical model was developed to investigate the impact of the availability of return items in the market on acquisition price management. Here, three different methods of collection of return items from the market are considered: direct method, indirect method and coordinated method. A numerical study was conducted to illustrate the mathematical model, and an extensive sensitivity analysis was carried out for the three different methods of collection to examine the impact of market size and the available dependency factor on acquisition price and the channel profit. The results show that the total channel profit increases when the acquisition price increases for the direct method of collection. Furthermore, the results reveal that the total channel profit increases when the market size increases for the coordinated method of collection compared with the other two methods of collection.     

Closed-loop supply chain system with energy,transportation and waste disposal costs

Energy usage and consumption play important and strategic roles in modern manufacturing, inventory and logistics systems. The literature on inventory models for closed-loop supply chains reveals that, for no clear reasons, energy costs were ignored along with transportation and disposal costs. This paper introduces a closed-loop supply chain model that considers the economic value and energy content of products. It also offers a novel framework for studying lot-sizing policies of production processes in that context. Thus, a mathematical model for a closed-loop supply chain system with energy, transportation and disposal costs is developed. Numerical examples are provided with their results discussed. The developed model was also compared to that of Richter (1996) to stress the importance of accounting for the three noted costs. The numerical results emphasise that accounting for energy, transportation and disposal costs in supply chain modelling increases the sustainability of a production-inventory system due to the strong interdependence of the three costs on one hand, and their relationship to the environment on the other hand.     

Issues in reverse supply chains,part II: reverse distribution issues – an overview

In recent years, due to growing environmental concern, there has been an increasing attention to product take‐back, product recovery and the re‐distribution of end‐of‐life products. Reverse logistics (RL), which refers to the distribution activities involved in product returns, has recently received much attention because many companies are using it as a strategic tool to serve their customers; and can generate good revenue. The management of return flow usually requires a specialised infrastructure with special information systems for tracking and dedicated equipment for the processing of returns. An efficient reverse distribution structure may lead to a significant return on investment as well as a significantly increased competitiveness in the market. Therefore, the time seems to be right for a systematic overview of various issues that are arising in the context of reverse distribution. The main purpose of this paper is to review the literature on RL and suggest a classification based on reverse distribution issues. The result of this research provides a better understanding of the RL concept and outlines some future directions of research on modelling and analysis.     

Sustainable tyre remanufacturing: an agent-based simulation modelling approach

This paper addresses sustainable benefits of remanufacturing tyres. An agent-based simulation approach is used to tackle this research problem by identifying different agents such as tyre, collector, recycler and remanufacturer. Details related to every agent are provided to show the decisions taken by these agents and the impact that may have on tyres' remanufacturing industry. Relying on input data from published reports and papers by academics and professional organisations, experiments are conducted on various scenarios to show the benefits of increasing the retread percentage of passenger car tyres. The results show that retreaded tyre can capture almost 25% of replacement (sales) market, resulting in significant reduction in scrap tyres and raw material consumption. This percentage can further be increased by increasing the number of retreads per used tyre and the life of tread rubber. The output results help in finding the profit break‐even point at various levels of retread. The results also show other decision-making implications, particularly related to rejection rate and ways to reduce it.     

Management of two competitive closed-loop supply chains

The two competitive closed-loop supply chains under our study include three members: two manufacturers and one retailer. In this paper, we focus on the management of the wholesale prices, the retail prices and the collecting prices for the two competitive closed-loop supply chains. On the assumption that the return rate of the used-products is an increasing function of the collecting price, we obtain the optimal wholesale prices, the optimal retail prices and the optimal collecting prices based on the following models: Model MMC (two manufacturers for collecting), Model MRC (manufacturer one and retailer for collecting) and Model RRC (retailer for collecting). Furthermore, by comparing the optimal results, we find that the retailer for collecting is the best channel for the two competitive closed-loop supply chains if the two manufacturers would like to transfer all of their cost savings from remanufacturing to the retailer. At the end, we illustrate a numerical example to analyse the impacts of the market share ratio and the substitute ratio of the two products on the optimal results.     

Performance evaluation of reverse logistics enterprise – an agent-based simulation approach

Reverse logistics (RL) has been applied in many industries and sectors since its conception. Unlike forward logistics, retracing consumer goods from the point of consumption to the point of inception is not a well-studied process. It involves many uncertainties such as time, quality and quantity of returns. The returned products can be remanufactured, have parts harvested, or be disposed safely. It is important to implement these activities in a cost-effective manner. The aim of this research is to measure the performance of the RL enterprise with the help of an agent-based simulation model. The major entities in the RL network are considered as Agents that can act independently. There are several different agents: collector agent, sorting-cum-reuse agent, remanufacturing agent, recycler agent, supplier agent and distributor agent. The individual performances of the agents are measured and recommendations are given to improve their performance, leading to the enhancement of the total performance of the RL enterprise. The approach is applied to a case study involving cell phone remanufacturing.     

Issues in reverse supply chain,part III: classification and simple analysis

Due to growing environmental concern and increasing awareness among customers, reverse supply chain (RSC) has received much attention among researchers and practitioners. Therefore it is necessary to provide a comprehensive list of references for other researchers (or readers), who are interested in RSC research to help stimulate further interest. In this paper, we present classification schemes and a simple analysis for the reverse supply chain. This literature review was mainly based on journal articles but also included web based documents, conference materials, working papers, etc. A total of 543 articles were reviewed, of which 506 were published between 1967 and 2008 from 100 reputed international journals. Based on the literature review carried out and the nature of research observed in RSC, we have introduced two classification schemes to systematically organise the published articles. The first classification scheme is based on the content related issues on RSC and the second one is based on the solution methodology followed by the researchers. These classification schemes indicate that there is considerable research potential for RSC. The results also show that there is strong growth in RSC research.     

Issues in reverse supply chains,part I: end‐of‐life product recovery and inventory management – an overview

Recovery of used products has become a field of rapidly growing importance in reverse supply chain management. Product recovery includes collection, inspection/separation, disassembly, reconditioning/reuse, remanufacturing, and recycling. In real time situations, the collection of end‐of‐life (EoL) products from the customer and their return to the manufacturer is tedious and time consuming. Reduced product life cycles have increased the rate of product returns and disposals. Owing to shortened product economic life cycles, the recovery of value from EoL products is becoming a necessity. Companies have realised the value that they could recover by remanufacturing or recycling EoL products. Researchers have developed various models for product recovery network design, optimal inventory, production planning and control, remanufacturing, recycling, disposal, etc. The main purpose of this paper is to review the literature on EoL product recovery and inventory management issues in reverse supply chains and to outline some future directions for research on these issues.     

Impact of incorporating customer preference in sustainable remanufacturing of commercial returns

This paper investigates optimum production parameters for a reverse supply chain for manufacturing of primary products and remanufacturing of commercial returns (products returned by customers for refund or exchange). The market for the product consists of two categories, the primary and remanufactured products. The demands for these markets are independent and considered to be random variables following a normal distribution function. The approach presented in this work differs from many previously published works because the acceptability of products varies among customers. The interaction between the designed quality and variable customers’ preferences determines the likelihood of a product being returned. Two major decision variables targeted in this study are the production cycle time and the targeted quality for production of parts used in the product. Through an analytical formulation and numerical examples, a relationship between the total profit of the system and the two decision variables is developed and optimised. The analysis demonstrates that the total profit of the hybrid system could be increased significantly by targeting the optimum targeted (not necessarily the highest) values for quality of parts and the optimum cycle length. And this objective could be accomplished with significant gain with respect to sustainability and waste reduction.     

The study of production and inventory policy of manufacturing/remanufacturing environment in a closed-loop supply chain

The life cycle of electronic and electrical equipment has been ruthlessly shortened due to the rapid promotion of new products. Such a phenomenon has thereby resulted in serious environmental pollution and damages to the natural ecology. In order to reduce electronic wastes and increase recycling products, a manufacturing/remanufacturing simulation model was constructed through a series of inventory management policies. The model included the use of the traditional supply chain structures for the forward movement of goods to consumers, as well as a number of specialised operations required to perform reverse supply chain activities. Such a model took into account all the supply chain members such as the suppliers, manufacturers, logistics centres and customers at the same time. Finally, a case study on the application of the model was conducted.     

再生资源供应链的结构、行为和绩效分析

再生资源是一种特殊的资源类型,兼具资源资产产权和环境产权,两者相互作用引导其开发利用自组织形成了正规与非正规回收利用者相互交织的完整逆向供应链系统。协调其中各主体间的利益关系、减少逆向供应链的环境污染和整体运行损耗是再生资源开发利用水平提升的关键手段。为此,本文以北京市废旧电视为例,利用实地调研的方法,系统分析了再生资源供应链的结构、行为和绩效(SCP)。结果表明:(1)消费者选择一级回收者时具有价值性、便捷性和规范性三种偏好。销售商回收模式可较好地满足消费者的需求,成为其首选方案,然而,"以旧换新"限制了无需购买新电视的人群。游商以45%的份额占据了剩余一级回收市场的主导地位。(2)一级与二级回收者间形成了稳定的合作关系,二手市场扩大了一级回收者的利润,中间商则为一级回收者提供了稳定的需求保障。(3)受到非正规拆解作坊的挤占,正规拆解企业产能严重过剩。一方面,降低了拆解企业对收购产品的质量要求,致使中间商偷换有价组件和跨境转移电子废弃物等问题日益严重。另一方面,正规拆解企业会提高收购价格,致使政府补贴的基金大部分转移至回收环节,巩固了现有的正规与非正规回收者共存的供应链结构。(4)个体中间商及非正规拆解利用作坊是再生资源供应链低效率的关键。本文调整了现有的家电基金制度,建议在电视销售环节向消费者征收40元/台的基金,并将其中的10元/台用于扶持政府可管控的正规主体中间商,代替个体中间商的功能,其余金额可用于弥补现有基金的亏空。该种模式可充分利用现有的一级回收者及二手市场,并可有效提升再生资源供应链的整体绩效水平。     

A case study on period vehicle routing in a refuse collection system

Period vehicle routing, a multi-period extension of the capacitated vehicle routing problem, is the problem of determining a service combination of each customer as well as the vehicle routes in each period of the planning horizon while satisfying the restrictions on the vehicle capacity and the travel distance (time). The problem can typically be found in refuse collection systems in which end-of-life products or wastes are collected and moved to the facilities where further treatment is taken care of. In this study, we report a case study on the problem for the objective of minimising the fleet size, i.e. the maximum number of vehicles simultaneously required over the planning horizon. To solve the problem, we adopt the two-stage heuristic in which an initial solution is obtained by assigning a service combination to each collection point, and then it is improved by changing the service combination assigned to each collection point. Computational experiment was done on the case data and significant improvement over the conventional method is reported.     

猪肉可追溯体系建设存在问题与影响因素——基于猪肉供应链的实证分析

为防范食品安全风险、推动猪肉可追溯体系建设,近年来我国农业部、商务部和质检部等不同监管部门从各自职能出发,分别发布了指导生产环节、流通环节等不同环节猪肉可追溯体系实施的标准与规范。然而到目前为止,我国真正意义上的全程猪肉可追溯体系尚未建立。本文基于猪肉供应链,实地走访调查了供应链上的盐城生猪屠宰加工A企业,盐城部分农贸市场与超市,以及盐城阜宁县部分万头以上猪场(以下简称大户)和生猪养殖散户(以下简称散户),细致梳理猪肉可追溯体系实施的现状与存在的问题,结果发现,养殖环节的生猪已百分百佩戴耳标,但效果却形同虚设,养殖环节与屠宰环节之间的信息无法通过耳标进行有效对接,猪贩子时常临时加戴耳标。进一步深入研究发现,造成上述现象得深层次原因是:生猪身份标识编码方式、信息记录的格式、信息上传的规范与管理平台等标准不统一,智能识读设备和数据库等配套技术不完善,体系后期运行与维护投入不足等。据此,本文提出了推动和完善我国猪肉可追溯体系建设的对策建议。     

浅析供应链、价值链理论的发展与价值型企业的特征

本文在阐述供应链、价值链理论发展的基础上，进一步分析了供应链与价值链的联系与区别，指出基于建立企业长期竞争优势的“价值型企业”与传统的“经济型企业”的区别。并提出价值型企业四个方面的主要特征，即，追求“创造价值“和“利润”双重目标；善于构造“企业生态”；追求与自然生态的互利共生；努力使企业成为“学习型组织”等。     

Developing a fuzzy linear programming model for locating recovery facility in a closed loop supply chain

In this research a closed loop supply chain is designed which incorporates reverse logistics and forward logistic system simultaneously. In the design of reverse logistic system, recovery options are embedded in traditional supply chain for treating returned products. The recovery system includes collection centres, remanufacturing plants and disposal centres. Since the product return is supply driven, there is an uncertainty about it. In the proposed configuration for closed loop supply chain, the optimised configuration for supply chain in terms of locating recovery plants is developed. Accordingly, a fuzzy mixed integer linear programming model develops to deal with the uncertainty of returning products by customers. A general-purpose solver (LINGO 8.0) and a Meta heuristic approach (genetics algorithm) are implemented to solve the proposed model. The answers are compared by defining indexes and then the optimal answer, configuration and variables are identified. This solution will suggest a new design of supply chain network in which waste of materials is minimised and the new raw materials are necessary only when the used products may not be recovered by recovery options.     

Reverse logistics network design: a conceptual framework for decision making

Reverse logistics play a significantly increased role in supply chains. Producers are incorporating reverse logistics into their supply chain design because of governmental legislation, economic benefits from product recovery, and customers' demands for better environmental practices. Motivated producers face two main challenges in reverse logistics network design: (1) how do you build product recovery activities into traditional forward logistics networks? and (2) how do you manage the impact of uncertainty in the reverse logistics supply chain? Moreover, producers need to consider many tradeoffs leading to efficient network design. Published case studies have discussed these tradeoffs, and we describe a framework to evaluate these tradeoff considerations. We then apply the framework to three new case studies: medical device refurbishing, municipal e‐waste recycling, and carpet fibre recycling.     

Identifying the factors influencing the performance of reverse supply chains (RSC)

This paper aims to extract the factors influencing the performance of reverse supply chains (RSCs) based on the structure equation model (SEM). We first introduce the definition of RSC and describe its current status and follow this with a literature review of previous RSC studies and the technology acceptance model . We next develop our research model and 11 hypotheses and then use SEM to test our model and identify those factors that actually influence the success of RSC. Next, we use both questionnaire and web‐based methods to survey five companies which have RSC operation experience in China and Korea. Using the 168 responses, we used measurement modeling test and SEM to validate our proposed hypotheses. As a result, nine hypotheses were accepted while two were rejected. We found that ease of use, perceived usefulness, service quality, channel relationship and RSC cost were the five most important factors which influence the success of RSC. Finally, we conclude by highlighting our research contribution and propose future research.     

绿色供应链管理：企业经营管理的趋势

在供应链的各个阶段中从原材料获取到产品的制造、运输、使用过程都会产生废弃物,对环境造成严重的污染,威胁人类的健康和生态系统系统。为此,本文提出了以供应链管理的概念,并讨论了它的主要内容以及实施绿色供应链管理的应用前景。