对象标识统一化程度影响物流资源整合的系统动力学分析

为了分析对象标识统一化程度对物流资源整合的影响,提出利用系统动力学理论建立反馈模型。采用2002年以来国家统计局和《中国现代物流发展报告》的数据,设计模型变量,并进行回归,以确定变量关系方程式。在该模型中采用物流资源利用率、企业间合作比例、物流行业总收益作为衡量物流资源整合水平的指标,运用Vensim仿真对象标识统一化程度与三者之间的相互影响。模拟结果显示对象标识统一化程度对物流资源利用率、企业间合作比例和物流行业总收益均有正向影响。该研究表明提升对象标识统一化程度可以有效提高企业间的沟通,促进物流资源整合水平的提高,实现物流产业对经济增长的可持续拉动作用。     

中国物流业碳排放特征及其影响因素分析——基于LMDI分解技术

在对我国物流业碳排放特征进行分析的基础上,运用LMDI分解技术,建立中国物流业人均碳排放的因素分解模型,定量分析了1991-2010年能源结构、能源效率、运输方式、物流发展、经济增长以及人口等6种因素对物流业人均碳排放的影响.分析表明:经济增长是拉动物流业碳排放增长最主要的动力,在研究期间呈指数增长的趋势.运输方式对碳排放增长也表现出明显的促进作用,能源结构和能源效率虽然表现出拉动作用,但效果微弱.而物流发展因素则对物流业人均碳排放量表现出明显的抑制作用.因此,应大力推进物流业科技水平的提高,进一步发挥物流发展因素对碳排放的抑制作用,同时,优化物流运输体系,形成以铁路为主体,水运和管道为支撑,公路和航空运输为辅的低碳化的综合运输体系.     

Logistics Planning in the Downstream Oil Industry

Strategic logistics chain planning is of great importance within the downstream oil industry. Logistics networks originate at refineries and terminate at the final delivery point — the customer. Types of bulk transportation used and the main product classes are described. The business decisions which need to be addressed are stated. A corresponding model is formulated partly in mathematical and partly in qualitative terms. The cost of road vehicle delivery to customers is modelled. The business risks associated with changes to the logistics infrastructure are indicated.     

A closed-loop logistics model for remanufacturing

Recoverable product environments are becoming an increasingly important segment of the overall push in industry towards environmentally conscious manufacturing. Integral to the recoverable product environment is the recoverable manufacturing system that focuses on recovering the product and extending its life through remanufacture or repair. Remanufacturing provides the customer with an opportunity to acquire a product that meets the original product standards at a lower price than a new product. The flow of materials and products in this environment occurs both from the customer to the remanufacturer (reverse flow), and from the remanufacturer to the customer (forward flow). Since most of the products and materials may be conserved, essentially this forms a closed-loop logistics system. We present a 0–1 mixed integer programming model that simultaneously solves for the location of remanufacturing/distribution facilities, the transshipment, production, and stocking of the optimal quantities of remanufactured products and cores. We also discuss the managerial uses of the model for logistics decision-making.     

Simultaneous engineering approach to an integrated design and process planning

To support integration of design and process planning, a reference model has been developed. This reference model represents the basis for a new methodology for integrated design and process planning which enables a Simultaneous Engineering approach in the early stages of product development. The reference model consists of four partial models. These are the activity model, the information model, the technical system model and the model of integrating methods. Using these models, the methodology enables a concurrent processing of design and process planning activities with regard to different components of a product. Furthermore, the methodology covers planning methods as well as execution methods, to support early transmission of information to downstream activities and a feedback of information to upstream activities within the process chain of design and process planning.     

影响我国物流企业信息化水平的关键因子分析

目前我国物流业信息化水平低,为加速我国物流业信息化进程,急需找到影响我国物流企业信息化水平的关键因子,以便能针对性地采取对策.首先基于现有文献,初步找出影响我国物流企业信息化水平的全部主要因素,然后采用因子分析方法,得出影响我国物流企业信息化水平的关键因子有九类,即政府支持因子、信息化技术因子、物流产业发展因子、信息化实施因子、信息化人才因子、行业与企业管理因子、信息化风险因子、信息化资金因子、利益相关者信息化水平因子.     

Multi-period reverse logistics network design for used refrigerators

This paper focuses on the design of a multi-stage reverse logistics network for product recovery. Different recovery options such as product remanufacturing, component repairing and material recycling are simultaneously considered. Initially, we propose a mixed integer linear programming model – with a profit maximization objective – for the network design problem. The structure of the product, by way of bill of materials (BOM), is also incorporated into the proposed model in order to analyze the flow at component and material levels. Sensitivity analysis is carried out to study the effects of variations in the values of the input parameters such as product return quantity, unit transportation cost per unit distance, and unit processing cost. The analysis shows that the design decisions of different facilities considerably change even for 5–20%% variations in input parameter values. This led to the development of a refined mathematical model which incorporates variations in the different input parameter values over time. The new model provides a unified design for the entire planning horizon and has been validated with the design of a used refrigerator recovery network.     

Multi-period reverse logistics network design

The configuration of the reverse logistics network is a complex problem comprising the determination of the optimal sites and capacities of collection centers, inspection centers, remanufacturing facilities, and/or recycling plants. In this paper, we propose a profit maximization modeling framework for reverse logistics network design problems. We present a mixed-integer linear programming formulation that is flexible to incorporate most of the reverse network structures plausible in practice. In order to consider the possibility of making future adjustments in the network configuration to allow gradual changes in the network structure and in the capacities of the facilities, we consider a multi-period setting. We propose a multi-commodity formulation and use a reverse bill of materials in order to capture component commonality among different products and to have the flexibility to incorporate all plausible means in tackling product returns. The proposed general framework is justified by a case study in the context of reverse logistics network design for washing machines and tumble dryers in Germany. We conduct extensive parametric and scenario analysis to illustrate the potential benefits of using a dynamic model as opposed to its static counterpart, and also to derive a number of managerial insights.     

A warehouse-based design model for reverse logistics

In this paper, an MILP formulation is proposed for the design of a reverse logistics network based on a warehouse location–allocation model, which optimizes, simultaneously, the forward and reverse networks. A single product model with unlimited capacity is first defined. Subsequently, the model is extended to a multi-product capacitated recovery network model, where capacity limitations and a multi-product system can be considered. The proposed model is compared to published work in the field, where different model assumptions have been proposed. Two cases are described so as to gain a better insight into the model and allow a comparative analysis.     

长沙市物流产业发展动因分析

基于物流产业空间格局演化,分析物流产业发展动因机制.结合试点城市特点,构建试点城市物流产业影响因素模型,运用回归分析对长沙市物流产业影响因素进行实证研究.研究结果表明:服务业的市场需求、服务业的开放度、信息技术水平和市场反映能力,对长沙市物流产业发展有正向促进作用.     

基于灰色关联模型的家具产业集群与区域物流联动发展研究——以江西省为例

选取2003-2013年度数据,基于灰色关联模型,对江西省家具产业集群与区域物流联动发展进行了实证分析,得出以下结论:江西家具产业集群最大的制约因素为货运总量和货运周转量,同时,江西家具产业集群中的家具总产值为区域物流发展的最大制约因素.江西家具产业集群与区域物流具有较高的关联性和协调性,但两者之间协调耦合度具有较为明显的波动性.为有效实现江西省家具产业集群与区域物流的联动发展,提出相关建议.     

Logistics distribution network design with two commodity categories

In this paper, we study the design of a logistics distribution network consisting of a supplier, a set of potential warehouses, and a set of retailers. There are commodities from two product categories, that is, category A and category B, flowing across the network. The demand for commodities in product category A is stable. The demand for commodities in product category B is highly uncertain. We show that the network design problem to distribute the commodities in both product categories can be formulated as the uncapacitated facility location problem with monotone submodular costs and tackled using a cutting plane algorithm. We propose a strongly polynomial time algorithm for the nonlinear discrete optimization problem, which must be solved in each iteration of the cutting plane algorithm. We also provide the computational results, and summarize the insights based on the proposed model and the solution algorithm.     

Optimizing reliability and service parts logistics for a time-varying installed base

Performance based contracting (PBC) emerges as a new after-sales service practice to support the operation and maintenance of capital equipment or systems. Under the PBC framework, the goal of the study is to increase the system operational availability while minimizing the logistics footprint through the design for reliability. We consider the situation where the number of installed systems randomly increases over the planning horizon, resulting in a non-stationary maintenance and repair demand. Renewal equation and Poisson process are used to estimate the aggregate fleet failures. We propose a dynamic stocking policy that adaptively replenishes the inventory to meet the time-varying parts demand. An optimization model is formulated and solved under a multi-phase adaptive inventory control policy. The study provides theoretical insights into the performance-driven service operation in the context of changing system fleet size due to new installations. Trade-offs between reliability design and inventory level are examined and compared in various shipment scenarios. Numerical examples drawn from semiconductor equipment industry are used to demonstrate the applicability and the performance of the proposed method.     

Combined DEMATEL technique with hybrid MCDM methods for creating the aspired intelligent global manufacturing & logistics systems

The concept of globalization has been prosperous in the past decades while manufacturing as well as logistics have already become one of the most significant issues in the globalization era. However, while modern globalized firms are leveraging both global manufacturing resources as well as logistics systems for pursuing higher quality, lower cost as well as product differentiation, how to evaluate, selecting an appropriate global manufacturing strategy by considering issues from both aspects of global manufacturing as well as logistics has become one of the most critical and difficult issues. Moreover, how the chosen intertwined global manufacturing as well as logistics system is to be optimized so that the aspired level of the global manufacturing system can be achieved have few been addressed. Thus, this research aims to resolve the above mentioned global manufacturing and logistics strategy selection as well as system reconfiguration issue. A Decision Making Trial and Evaluation Laboratory (DEMATEL) technique based novel multiple criteria decision making (MCDM) method with Analytic Network Process (ANP), Grey Relational Analysis (GRA) as well as VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR) will be proposed for selecting and re-configuring the aspired global manufacturing and logistics system. An empirical study based on the global manufacturing and logistics system design of a semiconductor company will be provided for verifying the effectiveness of this proposed methodology.     

Planning performance based contracts considering reliability and uncertain system usage

This paper investigates a novel quantitative approach for planning and contracting performance-based logistics in the presence of uncertain system usage. Our efforts focus on an integrated service delivery environment where the manufacturer develops capital-intensive systems and also provides after-sales support. We propose an analytical model to characterize system operational availability by comprehending five performance drivers: inherent failure rate, usage rate, spare parts inventory, repair time, and the fleet size. This analytical insight into the system performance allows the service supplier to minimize the total cost across system design, production, maintenance, and repair. Two contracting schemes are investigated under cost minimization and profit maximization schemes. For the first time in literature, reliability design and service parts logistics are seamlessly integrated into one decision support model for improving operational availability while lowering the lifecycle cost. Numerical examples are provided to demonstrate the applicability and the effectiveness of the proposed decision support tool.     

制造企业成品出入库两级排队协同服务模型

优化企业成品出入库协同服务水平、平衡工作负荷,从而提高企业仓储服务效率、降低物流成本,是现代制造企业亟待解决的一个重要的管理细节问题。针对这个问题,本研究以仓储入库和出库两个排队过程为研究对象,建立出入库等待时间溢出情景下的两级排队协同服务模型,分析了在排队等待时间控制目标下,出入库员工优化配置方案。该模型引入溢出和串联两个协同服务机制,分三种情景即前方与后方服务台都有空闲,前方繁忙与后方空闲,前方空闲(或繁忙)与后方繁忙,建立了各情景下的系统状态转移方程,求解系统状态的概率,并进而推算出反映系统表现的各项指标,如员工使用率,队列长度,等待时间,以及等待时间超过溢出界值的概率。用制造企业成品出入库管理案例进行验证分析,对企业目前采用的M/M/S出入库排队系统与两级排队协同服务系统进行了数值计算对比。结果表明后者能有效提升出入库服务效率,减少出入库排队系统平均等待时间,降低由于入库和出库两个服务过程效率不均衡而产生的企业内部物流成本,是提升企业内部物流协同管理水平的一个重要方法。其应用可以服务于仓储出入库协同管理的信息化与自动化水平的提高。     

Robust optimization for relief logistics planning under uncertainties in demand and transportation time

Emergency logistics is an essential component of post-disaster relief campaigns. However, there are always various uncertainties when making decisions related to planning and implementing post-disaster relief logistics. Considering the particular environmental conditions during post-disaster relief after a catastrophic earthquake in a mountainous area, this paper proposes a stochastic model for post-disaster relief logistics to guide the tactical design for mobilizing relief supply levels, planning initial helicopter deployments, and creating transportation plans within the disaster region, given the uncertainties in demand and transportation time. We then introduce a robust optimization approach to cope with these uncertainties and deduce the robust counterpart of the proposed stochastic model. A numerical example based on disaster logistics during the Great Sichuan Earthquake demonstrates that the model can help post-disaster managers to determine the initial deployments of emergency resources. Sensitivity analyses explore the trade-off between optimization and robustness by varying the robust optimization parameter values.     

An optimization model for the design of a capacitated multi-product reverse logistics network with uncertainty

In this work the design of a reverse distribution network is studied. Most of the proposed models on the subject are case based and, for that reason, they lack generality. In this paper we try to overcome this limitation and a generalized model is proposed. It contemplates the design of a generic reverse logistics network where capacity limits, multi-product management and uncertainty on product demands and returns are considered. A mixed integer formulation is developed which is solved using standard B&B techniques. The model is applied to an illustrative case.     

Development of an Air Force Warehouse Logistics Index to continuously improve logistics capabilities

For the effective operation of air power in the modern war, the logistics systems of Air Force warehouses need to be well-maintained. The best logistics system can be established through continuous improvements in logistics capabilities. Although there have been some studies on key performance indicators for logistics capability, they have neither considered the structural relationship among various influential factors, nor the feedback mechanisms in warehouse logistics capabilities. In this study, we propose a structural equations model (SEM) to develop an Air Force Warehouse Logistics Index (WLI). The concept of a Customer Satisfaction Index is used to assess the WLI for strategic improvement plans for various warehouse groups. It is expected that our model can be used to evaluate the logistics support capability of ROKAF (Republic of Korea Air Force) warehouses and contribute to warehouse modernization plans.     

快递企业“最后一公里”快件收派优化方案研究

本文以快递公司快件收派服务为背景,对区域收派路线规划问题进行研究,结合A快递公司实际运作情况进行案例分析,综合考虑收派混合、动态性、时间窗和容量约束四个最主要的因素,建立数学模型,设计收派流程,通过改进的禁忌搜索算法在短时间内得到优化的路径结果,并在收派活动进行中动态处理新需求及实时更新收派路径,以提高收派效率。基于该企业实际数据的计算结果表明,本文提出的相应流程和算法比实际操作获得更好的解。