生态旅游区固体废弃物回收的模糊优化模型

研究了生态旅游区固体废弃物逆向物流网络设计问题,包括中转站和处理站的2级选址.建立了成本最小和处理站距人们的最小距离最大化的双目标整数规划模型.考虑到废弃物产生量具有不确定性,提出了带有模糊参数的中转站和处理站选址的模糊优化模型,并用启发式算法给予求解.最后给出一个算例证明了算法的有效性和可行性.     

考虑负效应的城市废弃物中转站多目标选址模型及算法

现有研究中废弃物处理设施的负效应测度没有考虑风向、风力等因素的影响,不能很好地反映实际情况。本文提出了一种基于扩散距离的负效应测度方法;以带中转设施的城市废弃物三层物流网络为研究对象,建立以年均总成本和所有居民日人均负效应最小化为目标的中转站选址问题的混合整数规划模型;根据问题特征,设计一个模拟退火算法与贪心算法相结合的混合算法(HSA)同时求解设施选址、中转站容量及废弃物产生点的指派三个决策。算例结果显示,基于扩散距离的负效应测度方法能较好地反映实际情况;HSA算法在求解同类问题上是可行的和有效的。     

基于成本/服务权衡的逆向物流网络设计问题研究

逆向物流网络设计是企业获得经济利益和提高竞争力的战略决策之一。本文针对售后服务逆向物流网络设计问题,考虑了同时优化物流网络运营成本和服务水平,提出了一个多目标整数规划模型来确定服务中心的个数、位置、容量等级以及客户区指派到服务中心的策略,并得到成本和服务之间的权衡关系。设计了一种混合多目标进化算法求解模型。通过实例分析,找出了影响物流网络设计的关键因素。通过算例测试,对混合多目标进化算法和ε约束法进行了比较,结果表明混合多目标进化算法对求解中大规模的问题是一种良好的方法。     

考虑顾客选择行为的逆向物流网络设计问题研究

逆向物流网络设计是企业获得经济利益和提高竞争力的战略决策之一.本文在进行逆向物流网络设计时,考虑了企业和顾客有不同的利益,通过双层规划建模来描述物流网络设计问题.上层模型为双目标模型,描述企业同时优化物流总成本和服务水平,下层模型描述顾客选择回收点的行为.设计了求解算法,得到一组Pareto解构成的效率边界,通过分析效率边界,确定企业的物流网络结构.最后用算例验证了模型和算法的有效性.     

逆向物流网络设计研究进展

随着环境资源压力的增大,政府法制要求以及社会环保要求的提升,研究者对逆向物流网络的研究日益关注。本文系统地对近几年的逆向物流网络设计研究进行回顾,讨论并对比研究了网络设计研究问题,研究方法,定量模型,求解算法以及逆向物流网络设计中不确定环境方面的研究。探讨了逆向物流网络研究中的不足,为研究者未来的研究方向提供了参考。     

广西电子废弃物逆向物流网络设计与仿真

随着电子工业快速发展,如何有效回收和处理日益增多的电子废弃物已引起人们高度关注。在电子废弃物资源化利用过程中,逆向物流网络设计是一个关键环节。采用定量、定性、仿真相结合的方法构建网络模型。应用Lingo软件编程计算,得出在南宁、贵港、柳州建立中转仓库,考虑城市特殊背景,用仿真软件对逆向物流网络进行仿真研究,最后得出以柳州、南宁和贵港为一级中转仓储中心,钦州为二级中转仓储中心,贵港为处理中心和填埋场,其结果可为广西电子废弃物逆向物流网络设计提供依据。     

报废汽车逆向物流网络选址模型

本文构建了一个报废汽车逆向物流网络选址模型,以确定网络中设施的数量、位置及规模,并在由此构成的各条物流路径上合理分配物流量,以此解决报废汽车逆向物流网络回收拆解中心和再制造中心的选址问题。     

产品回收逆向物流网络优化设计模型

为了在传统正向物流网络基础上扩建产品回收逆向物流网络,基于混合整数线性规划方法建立了一种单产品、有能力限制的产品回收逆向物流网络优化设计模型,据此确定物流网络中各种设施的数量和位置,并在由此构成的各条物流路径上合理分配物流量,以使各种设施的投资和运营成本之和最小。给出了提高模型求解效率的Benders分解算法,并通过算例验证了模型和算法的有效性。     

建立第三方负责回收的再利用逆向物流网络的可行性研究

中在人们对环境保护和经济可持续发展重要性的认识日益加深的背景下，逆向物流应运而生。面对包装废弃物这类可再利用资源的浪费和对环境造成的污染，人们正在努力寻找能减少污染和使企业获益的途径。在介绍国内再利用逆向物流的现状后，针对存在的问题提出了利用第三方物流公司建立再利用逆向物流网络的必要性和可行性，然后提出了建立第三方负责回收的再利用逆向物流网络的思路。     

基于ELECTRE-Ⅱ算法的汽车制造企业逆向物流成本优化

逆向物流成本优化是降低企业总成本的一个重要途径。本文基于汽车制造企业逆向物流主要环节的成本分析,运用ELECTRE-Ⅱ算法对其逆向物流的多个运营方案进行了和谐性、非和谐性检验,进而确定方案间的级别高于关系,通过正向、反向排序并计算出平均序,最终得到了逆向物流成本管理的备选方案的优劣排序结果。     

A multi-objective and multi-period optimization model for urban healthcare waste’s reverse logistics network design

Various types of healthcare waste (or medical waste) generated by urban healthcare activities have increased due to the expansion of urban population and medical needs. As healthcare wastes are harmful to both the environment and human health, managing medical waste is becoming progressively more important. Constructing an optimized medical waste recycling network is one of the key problems in the management of urban healthcare waste. This paper conducts a two-stage reverse logistics network design for urban healthcare waste. The first stage involves the prediction of the amount of medical waste. Based on the Grey GM(1,1) prediction model, the amount of medical waste in multi-period of the target hospitals is predicted. In the second stage, a multi-objective model aimed at minimizing operating costs and minimizing environmental impact is developed for facilities allocation decisions, which include the configuration of key facilities such as hospitals, collection centers, transshipment centers, processing centers, and disposal sites, as well as medical waste flow control among facilities. A dynamic approach for the healthcare waste reverse logistics network is constructed by combining the Grey GM(1,1) prediction method with multi-objective optimization model. Sensitivity analysis of key parameters has been performed to analyze their impact on network performance. Some insightful management practices have been revealed.

     

THE IMPACT OF PRODUCT RECOVERY ON LOGISTICS NETWORK DESIGN

Efficient implementation of closed‐loop supply chains requires setting up appropriate logistics structures for the arising flows of used and recovered products. In this paper we consider logistics network design in a reverse logistics context. We present a generic facility location model and discuss differences with traditional logistics settings. Moreover, we use our model to analyze the impact of product return flows on logistics networks. We show that the influence of product recovery is very much context dependent. While product recovery may efficiently be integrated in existing logistics structures in many cases, other examples require a more comprehensive approach redesigning a company's logistics network in an integral way.     

Two-level network design with intermediate facilities: An application to electrical distribution systems

We consider the two-level network design problem with intermediate facilities. This problem consists of designing a minimum cost network respecting some requirements, usually described in terms of the network topology or in terms of a desired flow of commodities between source and destination vertices. Each selected link must receive one of two types of edge facilities and the connection of different edge facilities requires a costly and capacitated vertex facility. We propose a hybrid decomposition approach which heuristically obtains tentative solutions for the vertex facilities number and location and use these solutions to limit the computational burden of a branch-and-cut algorithm. We test our method on instances of the power system secondary distribution network design problem. The results show that the method is efficient both in terms of solution quality and computational times.     

逆向物流系统结构研究的现状及展望

随着环保意识的增强,废旧物品的回收再利用越来越受到广泛关注,逆向物流系统的研究也受到学者的重视。本文从研究的问题和方法两个方面较全面地总结了逆向物流系统结构的研究成果,重点讨论了逆向物流系统的结构特征、设计原则及设施的选址定位问题,并指出了进一步的研究方向。     

An integrated closed-loop product lifecycle management approach for reverse logistics design

Nowadays, reverse logistics is gaining importance for many companies in different industries. This importance is rooted in the fact that it generates profit and decreases the environmental impacts of products. Even though the decrease of environmental impacts is an indispensable requisite, reverse logistics design is only driven by cost indicators. The main reason behind this high cost is access to environmental information is difficult and is directly linked to data all along the lifecycle of the product. This paper presents a method by which reverse logistics design integrates environmental impacts based on the management of closed-loop product lifecycle. This method is divided into two processes: from beginning of life to end of life and from end of life to beginning of life. The first process integrates product data in order to calculate environmental impacts of the potential reverse logistics networks, whereas the second process selects the most appropriate reverse logistics network before optimising the product based on this particular network. The proposition is illustrated by a case study on a recycled aluminium automotive part.     

On multi-criteria chance-constrained capacitated single-source discrete facility location problems

This work aims at investigating multi-criteria modeling frameworks for discrete stochastic facility location problems with single sourcing. We assume that demand is stochastic and also that a service level is imposed. This situation is modeled using a set of probabilistic constraints. We also consider a minimum throughput at the facilities to justify opening them. We investigate two paradigms in terms of multi-criteria optimization: vectorial optimization and goal programming. Additionally, we discuss the joint use of objective functions that are relevant in the context of some humanitarian logistics problems. We apply the general modeling frameworks proposed to the so-called stochastic shelter site location problem. This is a problem emerging in the context of preventive disaster management. We test the models proposed using two real benchmark data sets. The results show that considering uncertainty and multiple objectives in the type of facility location problems investigated leads to solutions that may better support decision making.     

A goal programming model for paper recycling system

The conflict between economic optimization and environmental protection has received wide attention in recent research programs for waste management system planning. This has also resulted in a set of new waste management goals in reverse logistics system planning. The purpose of this analysis is to formulate a mixed integer goal programming (MIGP) model to assist in proper management of the paper recycling logistics system. The model studies the inter-relationship between multiple objectives (with changing priorities) of a recycled paper distribution network. The objectives considered are reduction in reverse logistics cost; product quality improvement through increased segregation at the source; and environmental benefits through increased wastepaper recovery. The proposed model also assists in determining the facility location, route and flow of different varieties of recyclable wastepaper in the multi-item, multi-echelon and multi-facility decision making framework. The use of the model has been illustrated through a problem of paper recycling in India.     

The value of acquisition price differentiation in reverse logistics

The quality of returned products may vary greatly, depending on their previous usage. Since the remanufacturing of products in good condition is more economically rewarding for the remanufacturer—and since even for non-remanufacturable products the value that can be extracted from their parts or materials may depend on the products’ quality—it seems logical to acquire used products of different quality levels at different prices. However, acquisition price differentiation requires the product quality to be revealed, i.e. the products are graded before their actual acquisition. We observe two different approaches in current practice. The first one is a decentralized system with several collection sites to which the customers can bring their used products. After a short grading procedure, they receive a specific acquisition price offer for their products, which they can accept or decline directly. The second setting is a reverse logistics system with a centralized grading facility. The final grading is conducted after shipping the used products to this specific facility. Motivated by these empirical observations, we compare the two strategies with the help of a continuous approximation model. We derive analytical expressions for the optimal pricing and network density decision and show that, in addition to the other factors discussed in the literature, acquisition price differentiation can be a reason for decentralizing the reverse logistics network, if the product quality is uncertain. Furthermore, we illustrate our results with a numerical example.