Concurrent optimization in designing for logistics support

Concurrent Engineering has always been an important field within military industry and is gaining recognition within commercial industry as well. Studies have suggested that long-range research efforts need to be directed to the area of integrated logistics. In order to satisfy the overall logistics objectives, product designs must incorporate consideration of the impact that design decisions have on operations, maintenance, transportation and supply. This paper presents a model that carries out a concurrent optimization of a product design and its associated manufacturing and logistics support systems. We offer this model as a framework for decision support of concurrent engineering activities.     

Distributing decision making using Java simulation across the World Wide Web

This paper describes a prototype distributed, multi-user Internet based simulation environment, written in Java, and its application to decision making. An example of its use is presented in the context of manufacturing. The motivating factor behind this work is the rapid development in computer controlled plants and systems, such as automated production lines. The growth in flexibility offered by computer control has led to increasing speed and complexity in scheduling of these systems. Making such decisions often requires the very high costs of moving expert modellers and Operational Research staff to factory sites. Following developments in computer supported concurrent working (CSCW) and concurrent engineering, it is suggested that a means for working in a geographically distributed manner is desirable. The availability of Internet based solutions, exploiting Java's distributed client server architecture makes it possible to prototype such ideas in a generally accessible manner. An environment built along those lines is described here. Its benefits are shown through a case study and ideas for future work are explored.     

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.     

Scheduling the part supply of mixed-model assembly lines in line-integrated supermarkets

Line-integrated supermarkets constitute a novel in-house parts logistics concept for feeding mixed-model assembly lines. In this context, supermarkets are decentralized logistics areas located directly in each station. Here, parts are withdrawn from their containers by a dedicated logistics worker and sorted just-in-sequence (JIS) into a JIS-bin. From this bin, assembly workers fetch the parts required by the current workpiece and mount them during the respective production cycle. This paper treats the scheduling of the part supply processes within line-integrated supermarkets. The scheduling problem for refilling the JIS-bins is formalized and a complexity analysis is provided. Furthermore, a heuristic decomposition approach is presented and important managerial aspects are investigated.     

Logistics network design for product recovery in fuzzy environment

The design of product recovery network is one of the important and challenging problems in the field of reverse logistics. Some models have been formatted by researchers under deterministic environment. However, uncertainty is inherent during the process of the practical product recovery. In order to deal with uncertainty, this paper employs a fuzzy programming tool to design the product recovery network. Based on different criteria, three types of optimization models are proposed and some properties of them are investigated. To solve the proposed models, we design a hybrid intelligent algorithm which integrates fuzzy simulation and genetic algorithm. Finally, several numerical examples are presented to illustrate the effectiveness of the proposed models and algorithm.     

Product life cycle analysis: a goal programming approach

This paper considers the role of Life-Cycle Costing (LCC), Time-Based Competition (TBC), and other relevant goals at the three planning-horizon levels of strategic, intermediate, and tactical with respect to time and cost of products to market in a concurrent engineering environment. A conceptual framework has been developed in which the general areas of LCC and TBC are delineated. Based on the conceptual framework, the specific components of LCC and TBC at each level of planning are developed and presented. Subsequently, a Preemptive Goal Programming (PGP) model is developed. This model uses the components of LCC, TBC, and other relevant goals as the decision variables. Then, a case study of a company that has developed LCC and TBC is considered. The PGP model is then applied to the company's operations by using the actual data obtained from the company in order to capture the essence of the conceptual framework. This example explains and validates the PGP model in practice and provides managerial implications of the solution. Finally, a set of conclusions and an assessment of the results are presented.     

Reliable design of a logistics network under uncertainty: A fuzzy possibilistic-queuing model

This paper proposes a bi-objective model for designing a reliable network of bi-directional facilities in logistics network under uncertainties. For this purpose, the model utilizes an effective reliability approach to find a robust logistics network design. The objectives of the model are to minimize the total costs and the expected transportation costs after failures of bi-directional facilities of the logistics network. To solve the model, a new solution approach is proposed by combining queuing theory, fuzzy possibilistic programming and fuzzy multi-objective programming. Finally, the computational experiments are provided to illustrate the effectiveness of the proposed model and solution approach.     

Priority planning of a dynamic complex product mix: Elements for a computerized interface between delivery times and plant utilization

The priority planning process is both the management of ensuring reliability in confirming delivery times and maximizing plant capacity utilization.A framework is presented for the decision process of order planning in a business environment with a dynamic product mix consisting of both standard and non-standard products and with a limited machine capacity.The concept of a computerized interface between the priority planning process and the confirmed order file is presented.A simulation study is done to determine the relationship between different manufacturing strategies, delivery time policies and plant efficiency. The method is applied to the production of engineering plastic materials.     

A hybrid approach integrating Affinity Diagram, AHP and fuzzy TOPSIS for sustainable city logistics planning

City logistics initiatives are steps taken by municipal administrations to ameliorate the condition of goods transport in cities and reduce their negative impacts on city residents and their environment. Examples of city logistics initiatives are urban distribution centers, congestion pricing, delivery timing and access restrictions. In this paper, we present a hybrid approach based on Affinity Diagram, AHP and fuzzy TOPSIS for evaluating city logistics initiatives. Four initiatives namely vehicle sizing restrictions, congestion charging schemes, urban distribution center and access timing restrictions are considered.The proposed approach consists of four steps. The first step involves identification of criteria for assessing performance of city logistics initiatives using Affinity Diagram. The results are four categories of criteria namely technical, social, economical and environmental. In step 2, a decision making committee comprising of representatives of city logistics stakeholders is formed. These stakeholders are shippers, receivers, transport operators, end consumers and public administrators. The committee members weight the selected criteria using AHP. In step 3, the decision makers provide linguistic ratings to the alternatives (city logistics initiatives) to assess their performance against the selected criteria. These linguistic ratings are then aggregated using fuzzy TOPSIS to generate an overall performance score for each alternative. The alternative with the highest score is finally chosen as most suitable city logistics initiative for improving city sustainability. In the fourth step, we perform sensitivity analysis to evaluate the influence of criteria weights on the selection of the best alternative.The proposed approach is novel and can be practically applied for selecting sustainable city logistics initiatives for cities. Another advantage is its ability to generate solutions under limited quantitative information. An empirical application of the proposed approach is provided.     

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.     

基于UTAUT视角的众包物流大众参与行为影响因素研究

众包物流作为一种新兴的终端物流配送模式,为有效解决当下火爆的本地化电商带来的“物流瓶颈”提供了全新的思路。本文以整合的技术接受和使用理论(UTAUT)为背景,提出了众包物流大众参与行为影响因素研究模型,采用调查问卷的形式搜集数据,并使用结构方程模型(SEM)的方法对收集到的296份有效样本进行分析。研究发现对众包物流大众参与行为的影响因素按总影响力从大到小排列依次为:便利条件、参与意愿、获益期望、社会影响、感知风险。最后,结合研究结果对众包物流的发展提出了针对性的对策和建议。     

An efficient domain decomposition method for three-dimensional parabolic problems

A non-overlapping domain decomposition algorithm to solve three-dimensional parabolic partial differential equations is presented. It has been shown in this paper that the algorithm is unconditionally stable and efficient. Spectral radii for the interface and interior region are provided. Unlike two-dimensional problem, it has been found out that estimating the values of the points of the interface in three-dimensional problem is no longer negligible.     

The development of modular-based design in considering technology complexity

Applying modularity in the designing of products has been extensively researched recently to reduce the delay of product development. This paper presents a methodology of modular-based design in the conceptual stage of systems to support concurrent engineering (CE). First, the functions (Fs) are classified into different types of modules according to the correlation in design by using fuzzy cluster identification. Second, the optimal module type is selected based on the considerations of the manufacture and assembly complexities of the system for progressive parallel design. Third, the design priority of Fs within a module is scheduled by measuring the information content of Fs. As a result, the traditional design process is arranged as a series-parallel action to reduce the design time of products. Finally, an automated guided vehicle (AGV) system is used as an example to describe this method.     

Interfacing architectural CAD data with KBS technology

The important task of communicating architectural geometry as a set of basic entities to Knowledge Based Systems (KBS) has in the past presented a number of unresolved problems. This paper addresses the critical issues and suggests an algorithmic strategy for their resolution. An example of a building plan mapped to a node-arc network representation illustrates the application of the methodology.The popular computer aided design package AutoCAD provides an environment for the interface which will form the primary module of an extensible Building Evaluation and Analysis SysTem, (BEAST).     

Design and validation of an unmanned surface vehicle simulation model

In this paper we present a multiphysics simulation model of Halcyon, an autonomous unmanned surface vehicle (USV). The simulation model presented in this paper has been developed to rapidly progress the design, development and validation of Halcyon’s autonomy management system, particularly in challenging sea conditions. Using simulation for this purpose enables extensive testing across the full environmental operating envelope of the vessel, hence greatly reducing the need for real-world sea-trials. The simulator is comprised of a novel and comprehensive sea-surface wave environment model, a six degree of freedom nonlinear unified seakeeping and manoeuvring boat dynamics model, an actuation dynamics model, an autopilot and an interface with an autonomy management system. Results are presented that show good agreement between real-world and simulated sea-trials data.     

基于体系工程与物流均衡的C2M服务制造物流体系结构模型

C2M服务制造是基于以顾客为中心的C2M(Customer to Manufacture)商业模式,是在服务型制造及生产性服务业为基础上而形成的一种新型产业模式。C2M服务制造要求构建合理的物流体系,而构建物流体系结构已经成为该研究的关键基础。本文基于体系工程和物流均衡理论,通过建立物流体系以解决C(客户)端与M(制造)端的短链式互联问题,在分析C2M服务制造物流体系特征和资源要素的基础上,给出了C2M服务制造物流体系的概念模型和结构模型,并运用价值函数分析体系状态是否优化,从而达到C端与M端快速互联的目标,进而解决了物流体系结构模型在C2M服务制造物流体系构建中的应用问题。     

带固定轴线成本的轴辐式网络设计问题

带固定轴线成本的轴辐式网络设计问题广泛应用于第三方物流、邮政和航空运输等领域. 现有研究主要考虑了枢纽站的节点成本, 本研究则强调合并运输的固定轴线成本. 固定轴线成本的必要性在于：轴辐式网络中的轴线运输需要借助更大型的运输工具, 因此必须支付固定成本. 建立了该问题的混合整数规划模型, 探讨了最优解特征, 并构造了求解问题的拉格朗日松驰算法, 实验显示算法具有非常好的求解效率与求解质量. 同时, 还讨论了一个重要的扩展问题：增加O-D流的绕道约束, 绕道约束常常应用于快递运输和应急物流等领域. 在局部修改原算法的基础上提供了扩展问题的求解方案.     

Analysis model visualization and graphical analysis attribute specification system

A visual environment for defining and manipulating engineering analysis information has been developed. This environment: (i) allows queries and modifications of the topology and geometry that defines a geometric model obtained from various geometric modeling systems, (ii) abstracts the modeler's functionality needed to associate analysis information, (iii) provides a hierarchical attribute association model, and (iv) gives a graphical user interface to both the geometric modeler abstraction and attribute management system. Finally graphical issues relating to performance, portability and flexibility of different workstation environments are discussed.     

基于时间的随机需求二级分销网络物流系统集成优化研究

分销网络设计包括设施选址、库存控制、运输等方面的设计与优化,但以往只是从战略层、战术层、运作层来分别进行各自的研究。实际上,这三个层次的决策要素之间存在着复杂的互动关系,并存在着广泛的效益悖反关系,这些在变化的环境下显得尤为突出。本文充分考虑时间因素的重要性,从物流系统的集成优化高度出发,研究建立需求随机的多分销中心多顾客的设施选址———运输路线安排———库存控制问题(ILRIP)的模型,对此设计了一个两层粒子群优化(PSO)算法,并给出了计算实例。研究结果有助于供应链分销网络的集成优化,缩短商品流转周期,提高顾客服务水平,提升竞争力。