The role of spot market in a decentralised supply chain under random yield

We consider a decentralised supply chain with demand uncertainty, wherein a manufacturer sells a single product that consists of two components to the end consumer through an independent distributor. Assume that one component has a random yield, the manufacturer may rely on the spot market to replenish any shortage components after the random yield is realised. We identify the optimal product order, component production and replenishment decisions under two different situations. One is the traditional arrangement that the distributor decides the product procurement quantity and the manufacturer chooses the production quantity. The other is vendor-managed inventory (VMI) arrangement in which the manufacturer is responsible for both the order and the production decisions. The results show that the role of spot market can effectively offset the negative effects from production yield’s, market demand’s and component spot price’s variances. Consequently, the spot market leads to the cooperation between the manufacturer and the distributor, and improves the channel’s overall performance, in particular under the VMI arrangement when the wholesale price is sufficiently high.     

风险厌恶下基于收入共享契约的供应链协调策略

在收入共享契约下,借助条件风险值理论研究风险规避零售商和风险中性供应商组成的二级供应链协调定价模型,推导出随机需求受价格影响的零售商最优零售价格、库存因子以及供应商最优批发价格。讨论风险规避系数、市场弹性系数和收入共享系数对分散供应链系统以及各成员运作绩效的影响。最后,进行数值算例,数值结果表明,随着零售商风险规避程度的增加,零售商和供应商运作绩效呈递减趋势,但采用收入共享契约可以有效的减少供应链系统以及各成员独立运作的绩效损失;当收入共享系数一定时,需求价格弹性系数越大,供应商和零售商运作绩效越小;然而零售商和供应商运作绩效并不受成本比例系数的影响。     

Coordinating a supply chain under demand and cost disruptions

In this paper, we investigate the coordination of a supply chain consisting of one manufacturer and n Bertrand competing retailers under disruptions of market demand and production cost. We present a coordination model of a supply chain under normal scenarios. Our findings demonstrate that the coordination scheme designed for the initial production plan should be revised when disruptions of market demand and production cost occur. To resolve this issue, we consider the possible deviation costs caused by disruptions and propose optimal decision models for different disruptions under centralised decision-making. We present an improved revenue-sharing contract model to coordinate the decentralised supply chain under disruptions. The proposed models are then further analysed through numerical examples.     

双渠道供应链的库存与定价策略研究

针对由传统零售渠道和网络直销渠道组成的双渠道供应链模型,考虑批发价格和传统零售价格确定情况下,同时市场需求随机且受价格影响时,对制造商在直销渠道上的最优定价和库存量决策,以及零售商在传统分销渠道上的最优订货量进行研究。通过模型分析和数值仿真说明：当需求分配比例处在一定范围内时,存在可行的直销价格。当加入直销价格不小于批发价格的约束条件后,在更小的需求分配比例范围内能够找到均衡解。且在此合理的区域内,传统零售渠道订货量减少,直销渠道库存量增大,但供应链总的销售量基本不变。零售商的期望收益有所增加,对于供应商,其来自于零售渠道的期望收益减少,来自于直销渠道的收益以及总收益增多。整个供应链的收益得到提高。     

单供应商面对具有多个销售点的零售商时的VMI模型研究

在供应商管理用户库存（VMI）环境中,当面临的具体条件不同时,供应商和零售商的利润分配是不同的,论述了当一个供应商面对具有多个销售点的零售商时的VMI模型,此时供应商负责库存决策,他可以在各个销售点之间转运（Transshipment）库存.建立了供应商和零售商的一个Stackelberg博弈,零售商作为领导者是通过决定销售价格来体现的.结果显示最终供应商和零售商可以达到一个子博弈精练纳什均衡,零售商在该模式下获得了很大的利润份额.给出了一个算例计算了均衡时的库存量和销售价格.     

Vendor-managed inventory and the effect of channel power

We analyze decentralized supply chains that follow general continuous review (Q, R) inventory policies subject to vendor-managed inventory agreements where the supplier chooses the order quantity Q, and the retailer chooses the reorder point R. Within the VMI scenario, we explore the effect of divisions of channel power on supply chain and individual agent performance by examining different game theoretic models. Optimal policies and analytical results, including existence and uniqueness proofs for equilibrium solutions under VMI, are derived. Numerical results are provided to compare the effectiveness of VMI and to analyze different channel power relationships under a variety of environmental conditions. We find that VMI can result in considerable supply chain savings over traditional relationships and that the relative division of channel power can significantly effect the performance of VMI. Interestingly, we find that the greatest system benefits from VMI arise in asymmetric channel power relationships, but that individual agents lack the incentive to assume a leadership role.     

A vendor-managed inventory scheme as a supply chain coordination mechanism

In this paper, we have considered a vendor-managed inventory (VMI) arrangement in a supply chain (SC), where the buyer imposes a penalty for shipments exceeding an upper limit. We have shown as how the industry practice of VMI under penalty can be used as a SC coordination mechanism. The vendor can influence the buyer to increase the batch size without making the buyer worse off. We also discuss how such a penalty scheme may be derived. Further, we have established the equivalence of VMI under deterministic demand with that of quantity discount models, thus highlighting the need to incorporate both cooperation and coordination perspectives while analysing SC collaboration mechanisms.     

Coordination of pricing,inventory, and production reliability decisions in deteriorating product supply chains

In this article, we study a two-level supply chain model for deteriorating items, in which the supplier’s production system is unreliable and the retailer’s demand is price-sensitive. The supplier’s production line may randomly shift from the in-control state to the out-of-control state. When the production line is in the out-of-control state, a proportion of the produced products will have bad quality. To mitigate the out-of-control risks, the supplier can improve the production line reliability by investing in high-quality machines, highly skilled workers, or advanced maintenance technologies. We start with the study of pricing and inventory problems concerning endogenous reliability in the integrated and decentralised scenario. To better illustrate the proposed models, two applicable algorithms are designed to determine the optimal production reliability, ordering quantity, and prices. Then, a cooperative reliability investment and revenue-sharing contract is proposed to coordinate the supply chain. Numerical examples and sensitivity analysis of the equilibrium strategies and coordinating results on key system parameters (e.g. deterioration rate, production rate, etc.) are given to verify the effectiveness of the contract, and meanwhile get some managerial insights.     

碳税情形下考虑低碳偏好的收益共享契约协调模型

研究考虑碳税和消费者具有低碳偏好情形的供应链碳减排的协调问题,得到实现供应链碳减排协调的必要条件。通过引入数量折扣策略,构建供应链碳减排的收益共享契约协调模型,解决纯粹的收益共享契约无法协调供应链碳减排的问题,并给出契约参数需要满足的条件。在消费者的低碳偏好以加法形式来影响市场需求时,通过模型优化,给出供应链的最优产品订购量和最优碳排放水平的确定方法。研究发现,在供应链协调时,供应商提供给制造商的批发价格是碳税的减函数,是碳排放水平的增函数;供应链系统的订购量与碳税成反比,而碳减排水平与碳税成正比,与碳减排系数成反比。     

Myopic vs. far-sighted behaviours in a revenue-sharing supply chain with reference quality effects

In this paper, we consider a dynamic supply chain where a manufacturer produces and distributes a featured product through an exclusive retailer to end consumers. The manufacturer decides the product quality and wholesale price, while the retailer sets the retail price in the presence of a revenue-sharing contract and consumers’ reference quality effects. The objective of this study is to investigate the impacts of myopic behaviour regarding the reference quality on the product quality and pricing strategies and profits of both members. Our results suggest that the manufacturer’s myopia leads to a higher quality, higher price strategy and a higher quality–price ratio which benefits consumers. Meanwhile, relative to the far-sighted behaviour, myopia results in a more quality-sensitive but less price-sensitive market demand. What’s more, we find that the manufacturer is apt to act in a far-sighted way, but the retailer isn’t always willing to cooperate with a far-sighted manufacturer. Taking myopic strategies for both members is likely to gain a high profit of the whole supply chain for a relatively high marginal contribution of product quality on demand and a relatively low revenue-sharing proportion.     

Optimisation of online retailer pricing and carrier capacity expansion during low-price promotions with coordination of a decentralised supply chain

In recent years, many online retailers in China set low prices on 11 November, which stimulates huge delivery demand and results in many problems although carriers make an effort to increase their delivery capacities temporarily. To circumvent this difficulty, we consider a supply chain consisting of an online retailer, who can set price to influence the demand, and a capacitated carrier, whose capacity can be expanded at a high cost. We derive the optimal decisions in the centralised and decentralised decision systems, and compare the performances of the two systems. We find that the optimal decisions, and which system has lower price, larger capacity increment, and more late delivered goods depends on the model parameters (the market scale, the late delivery costs, the capacity expansion cost, the delivery fee, and the demand uncertainty). Specially, we show that, contrary to the traditional channel, the online retailer in the decentralised system may set lower price and the carrier has less incentive to expand capacity in the decentralised system in some situations, which underlines the need for coordination. In addition, we propose coordination contracts to improve the overall performance of the supply chain under deterministic and random demands.     

Pull and push contracts in a decentralised assembly system with random component yields

This study investigates how random component yields can influence pricing and production decisions under pull and push contracts. We consider a decentralised assembly system where a manufacturer procures complementary components from two suppliers with random yields. We first characterise the centralised equilibrium decision as a benchmark and then analyse the equilibrium solutions in a decentralised assembly system under each contract. We find that neither contract is always superior to the other in terms of system profit. Under a push contract, suppliers always achieve the first mover advantage with higher payoff. However, the first mover advantage does not hold for the manufacturer under a pull contract. We further conduct sensitivity analysis to study the impact of random component yields and retail price on equilibrium solutions under each contract. Interestingly, the wholesale prices charged by suppliers always increase with supply yield uncertainty under a pull contract, but decrease under a push contract. In contrast with the centralised solution, the equilibrium quantities in the decentralised solution decrease with supply yield uncertainty under both pull and push contracts. We then extend our model to a general case with multiple suppliers. The system payoff decreases with the number of suppliers, and the main results derived in two suppliers setting still hold in the system with multiple suppliers.     

Competitive stocking and coordination in a multiple-channel distribution system

In this paper, we study a multiple-channel distribution system in which a manufacturer sells its product through an independent retailer as well as through his wholly-owned channel. The manufacturer and the retailer stock the product solely to satisfy the final customer demand of their respective channels. We focus on the stocking levels of the manufacturer's wholly-owned channel and the retail channel. We assume that each channel has a local stochastic demand, but that the products are substitutable, which means there will be spill-over customers in the event that one channel runs out of stock. We explore the channel inefficiencies induced by the presence of simultaneous vertical competition (double-marginalization) and horizontal competition (substitutability). We show that there is an overall tendency for both channels to overstock due to substitution, which intensifies under increasing substitution rates. Increasing double-marginalization, on the other hand, intensifies the tendency to overstock in the manufacturer's wholly-owned channel, but induces the retail channel to understock. We find that supply chain losses are least under moderate levels of double-marginalization and or substitution. We also investigate coordination mechanisms, and show that most of the well-known, simple contracts fail to achieve coordination in this setting. An exception to this is an appropriately designed penalty contract which can indeed coordinate the supply chain, but is hard to implement. In search of practically more appealing coordination mechanisms, we design a novel two-part compensation-commission contract, whose terms depend on the retail channel sales.     

A manufacturer’s production and pricing strategies with a salvage channel

We study a manufacturer’s production quantity and pricing decisions when the manufacturer has an opportunity to sell surplus inventory through a salvage channel. Before sales begin, the manufacturer determines the production quantity without knowing customer demand. After demand is realised, the manufacturer first satisfies the demand through primary channel while charging a fixed price or adjusting price to maximise profit. At the end of the selling season, the manufacturer resells surplus inventory through the salvage channel, which can be either integrated with or independent of the manufacturer. The manufacturer’s optimal production quantity and expected profit are investigated under different salvage channel structures. We show that the salvage channel improves the manufacturer’s profitability as well as the availability of the product to potential customers through both primary and salvage channels.     

价格随机条件下的应急双向期权数量弹性契约

旨在用期权应对批发价格波动的风险,用数量弹性契约来应对市场价格和市场需求随机波动带来的风险,探索双向期权数量弹性契约协调供应链的内在规律。将双向期权契约与数量弹性契约相融合,协调批发价、市场价格和市场需求均随机波动的供应链,寻找最优的供应链决策,并进行了算例仿真。研究结果表明：在批发价格波动时,采用双向期权弹性契约比采用基准数量弹性契约效果更好。双向期权弹性契约可以协调批发价格和市场价格均随机的供应链。     

Inventory misplacement and demand forecast error in the supply chain: profitable RFID strategies under wholesale and buy-back contracts

We investigate RFID adoption strategies under wholesale price and buy-back contracts in a supply chain with one manufacturer and one retailer who faces inventory misplacement and demand forecast error. RFID can alleviate the misplacement problem, and can reduce demand forecast error by shortening order lead time. By a newsvendor model, we characterise the optimal contract terms in the supply chain without and with RFID adoption, respectively. We further analyse how the contract terms depend on RFID-related parameters (e.g. salable rate and demand forecast error). We find that both without and with RFID, the wholesale price contract will lead to the double marginalisation problem, while the buy-back contract can coordinate the supply chain. We show that the supply chain adopts RFID if and only if the tagging cost is below a threshold; the threshold is in negative correlation to the demand forecast error. The supply chain is more willing to adopt RFID under the buy-back contract than under the wholesale price contract. RFID adoption can sometimes lessen the double marginalisation problem under the wholesale price contract, improving the supply chain efficiency. A smaller RFID tagging cost or a reduced forecast error do not necessarily lead to higher supply chain efficiency.     

供应商管理库存的价格效应研究

通过建立数学模型,论证了VMI在供应链中收益的非负性;在此基础上还给出了供求均衡价格与订货成本比、库存成本比的函数关系,该公式说明当订货成本比与库存成本比相差比较大时,VMI可以有效降低均衡价格,否则均衡价格将会上升。     

Coordination of a dual-channel supply chain after demand or production cost disruptions

Coordinating a dual-channel supply chain could not only achieve the integrated profit of the supply chain but also alleviate the channel conflict. Although some researches addressed this area, there is scant literature to discuss the coordination issue in the situations of disruption. To fill this void, we utilise a contract with a wholesale price, a direct channel’s price and a lump sum fee to coordinate a dual-channel supply chain under the cases of demand disruptions and production cost disruptions. After deriving the optimal contract for each case, we find that the manufacturer can achieve coordination of the disrupted supply chain by adjusting the parameters of the coordination contract used in a normal environment. We also show that after disruptions, there exists a contract adjustment benefit zone, in which both the manufacturer and the retailer can benefit from the adjustment of coordination contract when demand increases or production cost decreases. A further analysis of the production and distribution strategies in the coordinated dual-channel supply chain after disruptions suggests that the adjustment of the total production and sales of each channel depends heavily on the level of disruptions and the degree of consumers’ loyalty to both channels.     

Game theoretic analysis of horizontal carrier coordination with revenue sharing in E-commerce logistics

This paper proposes comparisons among two different competitive power structures with and without horizontal coordination. We conduct a game theoretic analysis on the situation where two logistics service providers compete in an e-commerce logistics market with respect to the order quantity and service level decision on a particular logistics service product. Under a consumer utility-based demand, we acquire the equilibrium order quantity decisions and optimal profits under the centralised setting and decentralised setting. An analytical model is established to examine the existence of the Nash equilibrium in the service game. We then prove that the logistics service demand depends on different competitive power structures with the establishment of Cournot game and Stackelberg game model. The analytical results and the equilibrium analysis of the e-commerce logistics system are investigated. After that, we compare the equilibrium results among the centralised system, Cournot game, and Stackelberg game. To empower the horizontal carrier coordination, we design a revenue sharing contract for the decentralised model. A numerical study illustrates the impact of parameters on the optimal decision variables. In this paper, we prove the effectiveness of horizontal carrier collaboration and explicate the reason for the lower marginal profit in logistics theoretically.     

供应链相关契约仿真的预付账款融资模型

以博弈论为模型的预付账款融资研究,在时间延迟和动态变化等复杂情况下无法求出解析解,为探究复杂环境下的供应链中的融资参数和决策参数的变化。本文以预付账款融资模式为研究对象,利用系统动力学原理分别构建了该模式下供应链采取批发价格契约和收益共享契约时的动力学模型,通过仿真模拟分析了在采取该两种不同契约下的相关数据。研究发现采取批发价格契约下零售商有更充足的继续采购资金,可以更快地完成资金周转;但是在采取收益共享契约时,在系统周期末供应链总收益更高。