A quantity flexibility contract model for a system with heterogeneous suppliers

This paper focuses on a quantity flexibility contract through which two or more heterogeneous suppliers periodically deliver a single type of product to a buyer as promised in the contract. The buyer starts each period by informing each supplier of the order size for the period and the reservation quantity for all future periods within a planning horizon. The order size for the current period is finalized according to the amount previously reserved, although this amount can be increased or decreased by a predetermined percentage of the reservation amount.In this paper, a linear programming model including several key features of a quantity flexibility contract is developed from the buyer's perspective. A rolling-horizon implementation strategy is suggested for efficient implementation of the contract. Computational experiments demonstrate that the proposed method can be used to determine a cost effective solution for the buyer in a reasonable amount of time.     

Commitment decisions with demand information updating and a capital‐constrained supplier

In this paper, we study a single two‐echelon supply chain with a capital‐constrained supplier (manufacturer) and a retailer. The supply chain faces a stochastic demand. As the production lead time is long, the market demand is updated during the supplier's production lead time. The supplier needs to determine the production quantity based on the original demand forecast, and the retailer needs to determine the time and quantity to order. The retailer can place an order before the supplier's production (preorder) or after the supplier's production (regular order). We prove the existence of optimal equilibrium solutions under both preorder and regular order strategies. We analytically investigate the order strategies for the supply chain agents under perfect and worthless market information updating. Moreover, we numerically analyze the impact of the information updating quality on the order strategy selection, and the effect of exogenous shocks on the supply chain agents.     

具有损失厌恶偏好零售商的供应链弹性数量契约

研究由风险中性供应商和具有损失厌恶偏好零售商组成的供应链在弹性数量契约条件下的协调问题.揭示了契约参数和零售商损失厌恶特性对零售商最优订货量的影响,发现调整弹性度这一契约参数可使供应链得到协调;同时,当弹性度满足一定条件时,调整批发价格也可实现供应链协调.最后通过数值分析,验证了弹性数量契约在协调供应链中的有效性,并探讨了其中原因.     

Vertical collaboration in the semiconductor industry: A decision framework for supply chain relationships

Vertical collaboration problem focuses on integrating and modeling the decision problems of the suppliers and buyers together with the market intermediary by identifying the inefficiencies in the traditional marketplace and aligning the incentives of members in the e-marketplace. The present work develops and solves real life e-marketplace models for complex buyers–suppliers procurement problems by estimating the order quantities in the collaborated supply chain. The newsvendor framework considers demand to be independent of the selling price as is generally the case in the semiconductor industry supply chain dealing with techno-savvy customers. The vertical collaboration process would be more effective if the length of the planning horizon and order size is considered as a negotiation parameter between the buyer and supplier. It is observed that the supplier’s expected profit function increases with the buyers’ ordering quantity, which is important in characterizing the general structure of the collaboration scheme of the supply chain.     

贸易信用下考虑零售商违约风险的供应链协调问题研究

本文研究延迟支付和提前支付同时存在下的供应链协调问题。考虑由一个供应商和一个零售商构成的二级供应链,市场需求随机,延迟支付下零售商会增加订购数量,但由于其违约风险的存在,供应商会降低其交付量,最终导致供应商交付量小于零售商订购量,降低供应链收益。要求零售商提前支付部分货款则可以有效避免零售商的违约问题,通过建立延迟支付和提前支付同时存在下的零售商收益模型和供应商的收益模型,给出了零售商的最优订购量决策和供应商的最优交付量决策,通过调整延迟支付期限和提前支付比例,使得二者相等,并等于供应链整体收益最大化下的生产数量,实现供应链协调。最后通过数值算例分析了相关参数的敏感性等问题。     

Capacity-constrained supplier selection model with lost sales under stochastic demand behaviour

In today’s market conditions, volume of demand is quite uncertain and thus it is hard to estimate. In many cases, buyer is prone to use supply chain flexibility rather than inventory holding strategy to withstand demand uncertainty. We assume that the buyer releases a replenishment order to the supplier for each cycle (or period) under the contract which is mainly composed of four parameters: (1) supply cost per unit, (2) minimum order quantity, (3) order quantity reduction penalty and (4) maximum capacity of the supplier. Based on these parameters, there are two flexibility options that buyer should evaluate in the order of cycle (1) issue an order smaller than the minimum order quantity and pay the related penalty and (2) place no order and lose the sales. Hence, Q _lost emerges as a critical buyer decision, the order quantity, below which no order is placed. Total expected supply cost plus lost sales, as a function of Q _lost is presented. We derive the optimal Q _lost that minimises the total cost function. Since capacity of each supplier is finite, we then develop a supplier selection model with total cost minimisation over the suppliers subject to capacity constraint that has a stochastic nature stemming from demand behaviour. Linearisation on the model is performed using chance-constrained programming approach. From a given set of supply bids from the potential supply chain partners, the buyer is able to make a quantifiable choice.     

A supply chain contract with flexibility as a risk-sharing mechanism for demand forecasting

Demand forecasting is one of the main causes of the bullwhip effect in a supply chain. As a countermeasure for demand uncertainty as well as a risk-sharing mechanism for demand forecasting in a supply chain, this article studies a bilateral contract with order quantity flexibility. Under the contract, the buyer places orders in advance for the predetermined horizons and makes minimum purchase commitments. The supplier, in return, provides the buyer with the flexibility to adjust the order quantities later, according to the most updated demand information. To conduct comparative simulations, four-echelon supply chain models, that employ the contracts and different forecasting techniques under dynamic market demands, are developed. The simulation outcomes show that demand fluctuation can be effectively absorbed by the contract scheme, which enables better inventory management and customer service. Furthermore, it has been verified that the contract scheme under study plays a role as an effective coordination mechanism in a decentralised supply chain.     

The relationships among supply chain partnerships,customer orientation,and operational performance: the effect of flexibility

The research goal of this study was to investigate how supply chain partnerships and customer orientation affect the operational performance of food service companies by moderating flexibility. In total, 725 invitation messages were mailed to members of Ihergo, Groupon, 17P, of which, 166 were returned (a return rate of 22.9 %). Structured equation modeling with PLS analysis allows empirical assessment of the measurement model used in this study. Companies will redefine their business models by connecting suppliers’ and customers’ view, and by integrating customers’ opinions and queries for the planning and development of new products. Linkage efficiency suppliers will reduce inventory and decrease perishable for food service companies based on the driving force to buy in the virtual environment. Product innovation and reduction of the time to market by supplier integration and customer integration are important to food service companies, and flexibility plays an important role in food service companies.     

基于生产负荷均衡的多对多订单分配模型

针对产业集群外的多个制造商和产业集群内的多个供应商的订单分配问题,从合理利用供应商剩余生产能力的角度,将多供应商之间的生产负荷率均衡作为订单分配决策的主要准则,建立了多个制造商对多个供应商的订单分配模型。通过对产业集群内注塑机零部件生产企业实例仿真分别从时间及空间维度验证了模型不仅可以减小供应商的生产负荷波动,而且可以均衡各个供应商在每个周期的生产负荷。基于生产负荷均衡的分配策略在保证制造商下达的订单得以顺利完成的同时,考虑供应商群体制造资源的均衡利用,从而提升整个供应商群体的运作水平和效益,进而实现整个供应链的优化。     

A dual-channel network design model in a green supply chain considering pricing and transportation mode choice

A green supply chain with a well-designed network can strongly influence the performance of supply chain and environment. The designed network should lead the supply chain to efficient and effective management to meet the efficient profit, sustainable effects on environment and customer needs. The proposed mathematical model in this paper identifies locations of productions and shipment quantity by exploiting the trade-off between costs, and emissions for a dual channel supply chain network. Due to considering different prices and customers zones for channels, determining the prices and strategic decision variables to meet the maximum profit for the proposed green supply chain is contemplated. In this paper, the transportation mode as a tactical decision has been considered that can affect the cost and emissions. Lead time and lost sales are considered in the modeling to reach more reality. The developed mathematical model is a mixed integer non-linear programming which is solved by GAMS. Due to NP-hard nature of the proposed model and long run time for large-size problems by GAMS, artificial immune system algorithm based on CLONALG, genetic and memetic algorithms are applied. Taguchi technique is used for parameter tuning of all meta-heuristic algorithms. Results demonstrate the strength of CLONALG rather than the other methods.     

面向物流的RFID应用系统研究

本文介绍了两种基于RFID的可视化供应链管理模型,并且设计了一种基于RFID的可视化供应链管理的原型系统。该模型可以实现供应商和用户之间的货物追踪,同时可以实时监控库存情况,发出预警信息,并且可以结合上下游的库存历史进行实时的发货预测。本文的模型分析和原型系统设计对于利用RFID技术改善供应链上下游信息不明的现况,提高供应链管理的效率和水平具有借鉴意义。     

Supply Chain Model for the Semiconductor Industry of Global Market

Supply chain management (SCM) is a new approach to satisfy customers of products and services via an integrated management for the whole business processes of the manufacturing from the raw material procurement to the product or service delivery to customers. With the rapid development of the information technology and global market environment the company is required to manage whole supply chain network to gain the competitiveness in business. Typically semiconductor industry is the one whose supply chain network is distributed all over the world, and its manufacturing process has the particular characteristics which has to be considered in the modeling of supply chain. In this paper we suggest the push and pull type supply chain models and their mathematical formulation for the semiconductor industry of the global market. Die bank between the front-end and back-end in the semiconductor manufacturing process is assumed to be the decoupling point by which two models are divided. Push supply chain model is based on the high throughput and the balance of the WIP flow, which takes the characteristics of re-entrant mechanism into account. Pull supply chain model is constructed considering order-based manufacturing, distribution and transportation process in order to meet customer's request appropriately. Development issues of the system and its implementation are also discussed.     

Using MDA for integration of heterogeneous components in software supply chains

Software product lines are increasingly built using components from specialized suppliers. A company that is in the middle of a supply chain has to integrate components from its suppliers and offer (partially configured) products to its customers. To satisfy both the variability required by each customer and the variability required to satisfy different customers’ needs, it may be necessary for such a company to use components from different suppliers, partly offering the same feature set. This leads to a product line with alternative components, possibly using different mechanisms for interfacing, binding and variability, which commonly occurs in embedded software development.     

Sole versus dual sourcing under order dependent lead times and prices

In this paper, we consider a dual-sourcing model with constant demand and stochastic lead times. Two suppliers may be different in terms of purchasing prices and lead-time parameters. The ordering takes place when the inventory level depletes to a reorder level, and the order is split among two suppliers. Unlike previous works in the order splitting literature, the supply lead time between vendor and buyer as well as unit purchasing prices is considered to be order quantity dependent. The proposed model finds out the optimal reorder point, order quantity and splitting proportion, using a solution procedure. Numerical results show that neglecting the relationship between ordering batch size and lead times is a shortcoming that hides one of order splitting advantages. Moreover, connecting unit prices to order quantity can decrease the percentage saving from dual sourcing compared to sole sourcing. Furthermore, sensitivity analysis shows some managerial insights.     

Exact and metaheuristic algorithms for the vehicle routing problem with a factory-in-a-box in multi-objective settings

Emergencies, such as pandemics (e.g., COVID-19), warrant urgent production and distribution of goods under disrupted supply chain conditions. An innovative logistics solution to meet the urgent demand during emergencies could be the factory-in-a-box manufacturing concept. The factory-in-a-box manufacturing concept deploys vehicles to transport containers that are used to install production modules (i.e., factories). The vehicles travel to customer locations and perform on-site production. Factory-in-a-box supply chain optimization is associated with a wide array of decisions. This study focuses on selection of vehicles for factory-in-a-box manufacturing and decisions regarding the optimal routes within the supply chain consisting of a depot, suppliers, manufacturers, and customers. Moreover, in order to contrast the options of factory-in-a-box manufacturing with those of conventional manufacturing, the location of the final production is determined for each customer (i.e., factory-in-a-box manufacturing with production at the customer location or conventional manufacturing with production at the manufacturer locations). A novel multi-objective optimization model is presented for the vehicle routing problem with a factory-in-a-box that aims to minimize the total cost associated with traversing the edges of the network and the total cost associated with visiting the nodes of the network. A customized multi-objective hybrid metaheuristic solution algorithm that directly considers problem-specific properties is designed as a solution approach. A case study is performed for a vaccination project involving factory-in-a-box manufacturing along with conventional manufacturing. The case study reveals that the developed solution method outperforms the ε-constraint method, which is a classical exact optimization method for multi-objective optimization problems, and several well-known metaheuristics.     

IOS drivers of manufacturer-supplier flexibility and manufacturer agility

In today’s hypercompetitive environment, it is critical for manufacturing firms to be agile in responding to ephemeral opportunities in the marketplace. This agility often requires the collaboration with supply chain partners. However, how a manufacturing firm collaborates with its suppliers to achieve agility remains an understudied issue. This study holds that manufacturing firms and their suppliers need to develop manufacturer-supplier flexibility accompanied with well-built integrated information systems and associated analytical systems (such as business intelligence) to enable manufacturer agility. To deepen our understanding of the roles of manufacturer-supplier flexibility and IOS technologies in facilitating manufacturer agility, we build and test a model based on the real options theory and bounded rationality. Based on 141 matched-pair samples of Taiwanese manufacturing firms, our findings demonstrate the importance of manufacturer-supplier flexibility in achieving higher manufacturer agility, wherein IOS integration enables better flexibility. We also show IOS-enabled analytical ability can strengthen the effect of such flexibility on manufacturer agility. Implications of the results for practices and academics are provided.     

考虑损失厌恶和锚定心理的供应链订货与协调

为更合理地实现供应链协调的整体最优绩效,以具有损失厌恶和锚定心理的零售商和风险中性的供应商组成的两级供应链为研究对象,探讨回购契约下的供应链订货及协调情况。建立集中和分散决策下考虑零售商损失厌恶和锚定心理的回购契约协调模型,分析了零售商最优订货量与批发价格、回购价格之间的关系,以及各契约参数对回购价格和各节点利润的影响,并给出了供应链实现协调需要达成的条件。结果表明,当零售商订购的产品为高利润产品时,能够实现供应链整体最优绩效,达到供应链协调,且利润在供应链双方之间的分配随着批发和回购价格的提升而向供应商倾斜,但零售商损失厌恶和锚定心理的加深会使得供应商提升回购价格,使整体供应链的利润下降,成本费用增加。     

A flexible three-level logistic network design considering cost and time criteria with a multi-objective evolutionary algorithm

Nowadays, time and cost are familiar criteria for every logistic provider, and both have been long treated to be minimized simultaneously. However, the criteria are naturally conflicted even with flexibilities and/or constraints appeared in the logistic networks. This paper is concerned with three-level logistic networks with potential suppliers, distributed centers (DCs), and deterministic demands from available consumers. The networks also benefit from potential direct shipments from suppliers to consumers as long as suppliers and DCs facilities might face limited capacity in their own seasonal supplying and warehousing processes. The goal is (re)configure the networks in order to minimize response time to consumers, transportation cost and facility cost. Therefore, the networks are formulated as multiple criteria decision making problems, which have more than one configuration through the time and cost optimizing at the same time. Due to the flexibility and the constraints, the decision maker(s) needs a set of compromise solutions for the networks that represent optimal configurations based on the objectives without considering prior knowledge. To this end, the problems are formulated into four individual logistic network models varying with the flexibility option and/or the capacitated facilities. To find the compromise solutions, Pareto-based multi-objective evolutionary algorithm, NSGA-II is customized and then utilized to deal with an illustrative case study. The results are analyzed through the two performance measures, hypervolume and the number of optimal solutions obtained so far.     

柔性契约协调机制下的供应链采购优化与决策

为提高供应链及链上各实体的收益,合理分配采购量,针对多个供应商和单一制造商组成的供应链系统构建了基于柔性契约协调机制的多对一供应链协调优化模型,分析了柔性契约协调机制对分散式供应链系统绩效的影响。针对多对一供应链结构中核心制造商有强议价能力的特点,建立了以制造商为主方、供应商为从方的Stackelberg主从对策模型,分别讨论了集中控制和分散控制下的最优决策。在期权契约下核心制造商通过设计合理的契约参数,可以激励上游供应商的决策行为,从而使得分散供应链系统的绩效能够得到提高。仿真实验证明了该柔性契约协调机制的有效性。实验结果表明,在一定的契约参数条件下,制造商不能随意设置其初始采购量,否则可能导致协调失效。     

基于软件代理技术的供应链协同管理

供应链是由供应商、制造商和销售商等企业部门为了进行物质材料获取、产品加工并将产品送达到最终用户的功能网络。供应链管理通过协调各种策略，控制管理供应链上各种工作流来优化供应链的运作.而优化的操作需要一种协同管理的方法。文中研究将供应链设计为由一系列智能软件代理组成的一个虚拟整体，每一个代理负责供应链上的某一项或某几项活动，代理间交互通讯完成供需活动。