考虑次品率的零售商库存联盟订货量与稳定性分析

通过建立含有次品率的确定性需求EOQ库存控制模型,探讨了在多个零售商结成联盟从同一供应商处联合订货且产品进行统一检测的情形下,零售商联盟的订货策略和联盟稳定性.得到了联盟的最优订货策略,并且由联盟的次可加性得出了结成联盟可以降低运作成本的结论.根据合作博弈中核与总体单调分配机制的概念提出了按比例对零售商合作联盟成本进行分摊的规则,并证明了在此规则下,大联盟是零售商联盟的稳定结构.通过数值例子对成本分摊规则的合理性进行了说明.研究结果为现实中零售商如何进行库存联盟和联盟之后如何制定运作策略提供了一定的参考.     

碳交易政策下供应链横向减排合作研究

在碳交易政策下,分析了由单个供应商和多个零售商组成的两级供应链横向减排合作问题。通过比较零售商间分散决策和合作决策下的最优成本与排放,发现横向减排合作不仅能够降低总成本而且能够降低总排放。进一步,采用合作博弈中子模博弈的方法,得到了实现横向减排合作中各零售商都能帕累托改进的充分条件,发现提高碳交易价格对横向减排合作有激励作用。考虑减排成本的分摊关系到减排的效率,提出了兼顾效率和公平的基于核仁的DEA结合Sharply值的减排合作分摊方法,并通过数值算例检验分摊方法的有效性。     

JIT采购方式对供应链的碳排放影响

零售商选择经济订购批量(EOQ)还是准时制(JIT)采购方式受到各种成本因素影响。在碳税政策下,以单供应商-单零售商组成的供应链系统作为研究对象,构建了供应链EOQ-JIT成本差异函数和EOQ-JIT碳排放差异函数,并对其解进行分析。最后利用数值分析,发现当供应商的年生产量较小时,零售商易于选择JIT采购方式,且供应链的碳排放比采取EOQ采购方式低;降低JIT采购方式的运输成本和运输产生的碳排放是实施JIT采购和降低供应链的碳排放的关键。     

基于协调成本的联合采购参与意愿分析

为了了解两个需求量不同的制造商参与联合采购的意愿,通过寻找他们在不同采购及库存管理政策下的经济订货批量(EOQ)及对应库存相关成本,得出存在协调成本下各制造商愿意进行联合采购的条件.研究结果表明,联合采购及联合库存管理可以降低制造商各自成本,并且需求量小的制造商对联合采购具有更大的热情,同时指出需要进一步完善成本分摊机制.文中对此给出算例进行了说明.     

逆向拍卖采购下的库存与定价联合决策

研究单周期下零售商的联合采购与定价决策问题。在该问题中,零售商首先确定一个采购合同,然后供应商投标,通过逆向拍卖选取一个获胜的供应商进行采购,同时确定产品的零售价格,目标是最大化其期望利润。假定需求函数是乘式的,在一定的条件下,证明零售商的期望收益(不包括采购费用)是采购量的凹函数,从而得到其最优的采购与定价策略。特别对正态需求分布情形给出了零售商的采购量和利润函数的解析表达式,并进行数值计算与分析。结果表明参与拍卖的供应商数量越多或供应商对其边际生产成本的估价越分散对零售商越有利。     

纵向合作广告与定价问题的博弈

基于单一厂商与单一零售商所组成的渠道结构,对合作广告费用开支与产品定价问题进行了研究.放宽了厂商和零售商边际利润为常量的假设,在模型中引入了价格这一决策变量.运用博弈论方法考察了Stackelberg主从博弈和协同合作博弈情形下厂商与零售商的最优广告及定价策略选择、厂商与零售商的最优利润及系统利润.通过对2种博弈均衡结果的比较,发现对渠道成员双方以及供应链系统甚至消费者而言,协同合作博弈结构要严格优于主从博弈结构.     

制造商服务努力下竞争与合作的双渠道供应链微分博弈分析

在电子商务环境下,研究了由两个制造商与一个零售商组成的双渠道供应链中制造商服务努力与广告费用分担,零售商进行广告促销的微分博弈模型,分别在制造商竞争与合作两种情况下得到并比较了各方最优均衡策略与利润。研究发现制造商服务努力和广告费用分担随着竞争的加剧而提高,但当零售商的边际利润较大时,将不会进行费用分担。分析了服务竞争、广告竞争和传统渠道需求所占份额对各方利润的影响,另外发现在合作模型下制造商利润之和增大,当服务效率差异程度在一定范围时,制造商会同时有合作意愿,并使得服务水平、广告投入及零售商利润降低。     

考虑价格折扣和运输柔性的库存运输优化研究

在考虑运输能力柔性和销售价格折扣的基础上,建立了零售商主导的分散优化模型、供应商主导的分散优化模型和库存运输联合优化模型,分析得出模型的性质。通过比较研究得出不同决策模式下最优策略和系统绩效的关系。研究表明,零售商主导的分散优化模型的库存成本小于运输库存联合优化模型的库存成本;零售商主导的分散优化模型的运输成本大于运输库存联合优化模型的运输成本;运输库存联合优化供应链的总成本小于零售商主导的供应链总成本。     

基于合作博弈和数据包络分析的联合库存成本分摊

第三方物流集成供应是降低供应链成本的有效途径,而集成供应要解决的一个关键问题是联合库存成本在各供应商之间的分摊。针对多供应商集成供应问题,提出了一种基于合作博弈和数据包络分析的联合成本分摊方法,得出合理的联合库存成本分摊比例。该方法充分考虑了联合库存各参与企业投入产出的贡献,对各参与方来说公平合理。算例证明该方法具有较高的可操作性和合理性。     

Shapley value对信息共享产生收益的分配研究

研究当零售商的销售信息共享时,产生的经济收益及其分配问题.分别考虑了信息共享产生的收益存在和不存在边际效用递减的两种情况.研究发现,不考虑边际效用递减时,供应商得到的收益是参与信息共享联盟零售商数目的正比例函数,每个零售商的收益保持不变;如果考虑递减效用,供应商的收益增加的速度随着参与联盟的零售商数目的增加而递减,每个零售商得到的收益也递减.     

The impact of retailers’ alliance on manufacturer’s profit in a dual-channel structure

When a manufacturer adds a direct sales channel to its existing retail channel, retailers may cooperate with one another to respond to this new competition. Our study develops a Cournot competition model in a dual-channel supply chain consisting of a manufacturer and multiple retailers. In a Stackelberg decision model, the manufacturer first sets the direct sales quantity and wholesale price, and then the retailers decide the order quantities. The results indicate that forming an alliance is not always beneficial for retailers. When direct sales cost is high, there is less likelihood for retailers to collaborate. On the other hand, retailers will form an alliance when direct sales cost is sufficiently low. This will likely reduce the manufacturer’s profit. As such decreasing direct sales cost is not necessarily beneficial for the manufacturer because of the retailers’ possible collaborative efforts. In addition, the study finds that when demand fluctuation increases or the manufacturer’s information accuracy decreases, it is more likely that retailers will form an alliance. After relaxing the assumption of homogeneous retailers, our numerical study validates the possibility of partial alliance. If some retailers’ marginal costs are sufficiently high, we could see the formation of a partial alliance.     

Analysis of retailers’ coalition stability for supply chain based on LCS and stable set

To attain the general form of stable coalition structure, this paper addressed the problem of retailers’ coalition stability in a two-stage supply chain consisting of one supplier and multiple retailers. A profit gain function was established via introducing market gain coefficient and coalition cost coefficient for different coalition structures. Based on the function, the profit of each retailer in all kinds of coalition structures was analysed, and the general feature of a stable coalition structure was attained by the largest consistent set method and the stable set method. Furthermore, some insights were obtained. For example, stable coalition structures are equidistributed or approximate equidistributed; with supplier’s cost increasing, the size of the retailers’ coalition increases. Finally, the above conclusions are verified by numerical simulation. The results of this paper provide a reference for retailers’ coalition in a supply chain, such as automobile or Information Technology supply chain.     

Joint production and shipment lot sizing for a delivery price-based production facility

A joint economic production quantity (EPQ) and delivery quantity model for a production system is investigated in this paper. More specifically, an EPQ policy is implemented in the production system, while a smaller shipping quantity is periodically dispatched to the customer. The production system is also responsible for the shipment cost, i.e. a delivery price-based procurement from the customer. The considered cost includes setup cost to launch the batch production, inventory carrying cost, and transportation cost, where the transportation cost is a function of the delivery quantity. A per unit time cost model is developed and analysed to determine the optimal production and delivery quantities. Under some mild conditions, it can be shown that the joint cost function is convex with respect to the production quantity; and the number of delivery is an integer in each replenishment cycle. Computational study has demonstrated the significant impact of the joint decision model on the operating cost. In particular, the reduction in total cost can be more than 15% when inventory carrying costs, and/or transportation costs, are high.     

消费者策略行为下全渠道服务区域及定价的优化研究

为了研究消费者策略性采购行为对于全渠道BOPS(buy-online-and-pick-up-in-store)运营服务区域和定价的影响,对全渠道零售商实行BOPS运营模式进行建模,并利用最优化理论(K - T条件)得到全渠道零售商的最优定价及最优服务区域。利用数值分析进一步证明消费者策略性采购行为是全渠道零售商制定BOPS运营服务区域和定价策略时应考虑的重要因素。研究表明,对于距离较远的消费者,全渠道零售商需要考虑顾客策略性采购行为,以争取到更多有顾客策略性采购行为的消费者来本店采购;而对于近处的消费者,全渠道零售商不需要考虑其行为,以减少全渠道零售商的渠道运行成本。此外,最优服务区的确定可以使得零售商以较少的渠道成本为消费者提供更好的服务,减少其运营决策失误。     

An equilibrium analysis of linear, proportional and uniform allocation of scarce capacity

In many industries a supplier's total demand from the retailers she supplies frequently exceeds her capacity. In these situations, the supplier must allocate her capacity in some manner. We consider three allocation schemes: proportional, linear and uniform. With either proportional or linear allocation a retailer receives less than his order whenever capacity binds. Hence, each retailer has the incentive to order strategically; retailers order more than they desire in an attempt to ensure that their ultimate allocation is close to what they truly want. Of course, they will receive too much if capacity does not bind. In the capacity allocation game, each retailer must form expectations on how much other retailers actually desire (which is uncertain) and how much each will actually order, knowing that all retailers face the same problem. We present methods to find Nash equilibria in the capacity allocation game with either proportional or linear allocation. We find that behavior in this game with either of those allocation rules can be quite unpredictable, primarily because there may not exist a Nash equilibrium. In those situations any order above one's desired quantity can be justified, no matter how large. Consequently, a retailer with a high need may be allocated less than a retailer with a low need; clearly an ex post inefficient allocation. However, we demonstrate that with uniform allocation there always exists a unique Nash equilibrium. Further, in that equilibrium the retailers order their desired amounts, i.e., there is no order inflation. We compare supply chain profits across the three allocation schemes.     

随机局部弹性与分批连续进货的随机存储模型

利用随机局部弹性的概念及运算法则,研究了分批连续进货并允许缺货的存储模型中,总费用对随机最高存储量与随机采购周期的局部弹性,给出了总费用弹性的联合概率密度的一般表达式,通过实例证明了当最高存储量与采购周期的分布特性已知时,总费用的弹性分布和弹性变化范围及弹性在该变化范围的可信度。     

An analysis of warehouse and distribution strategies

We consider a case where seven retailers, all belonging to the same organization, order independently from the manufacturer. The organization wants to evaluate the advantage of creating a centralized warehouse facility. However, the investment costs for such a warehouse are considerable and the organization is thus cautious that any cost savings must outweigh the investment cost. The multi-echelon inventory control literature does not indicate when a centralized warehouse is clearly the best option. However, there is evidence that a centralized warehouse may be advantageous for low demand items which are expensive, as opposed to inexpensive fast moving items. Also the costs of the additional warehouse (i.e., capital investment and operating costs) play an important role. Hence, whether or not a warehouse can reduce overall cost depends heavily on the additional cost of the centralized warehouse. In order to keep the investment cost low we consider an alternative to the centralized warehouse, called virtual centralized warehousing. In the latter system no additional investment costs are necessary (i.e., the existing retailers have excess capacity at their current facilities) and the benefits of central warehousing are achieved.     

A framework for decentralized multi-echelon inventory control

We provide a cost structure that can be used for decentralized control of a multi-echelon inventory system with a central warehouse and a number of retailers. This cost structure means that the warehouse, in addition to its local costs, pays a penalty cost for a delay at the warehouse to the retailer facing the delay. A basic assumption is that each installation starts with an initial policy concerning e.g., inventory control and transportation. The installations then play a Stackelberg game with the warehouse being [he leader. By minimizing its local costs according to the suggested cost structure, an installation can reduce its costs. The total system costs are then reduced by the same amount. No installation needs to face higher costs due to policy changes at other installations, since the cost structure satisfies a rationality constraint. If an installation applies its initial policy the local costs are the same as in the initial state, even if the other installations change their policies. If the game is played repeatedly the system will approach a Nash equilibrium but not necessarily the centralized optimal solution. As an example we consider a system with one-for-one ordering retailers.     

资金约束时零售商融资与订货决策及价值分析

针对供应链中存在资金约束的情形,建立了包含制造商（M）、零售商（R）双层结构、不考虑残次品率、库存成本和融资周期长短的简洁供应链决策模型。研究了当市场需求不确定和零售商资金不足情形下,零售商选择是否融资这两种情况下,其订货决策的变化,以及零售商和制造商的收益变化。通过有无融资条件下零售商不同数量自有资金时订货量和期望收益对比和零售商自有资本一定时订货量随周期变化的数值分析,证明了零售商的融资决策与订货量决策会随着其自有资金及市场需求的变化而变化;验证了融资可以提高零售商和供应链的收益,而且能够使得供应链的总产品尽快达到最佳产量,有效满足消费者需求。     

Optimal ordering decisions under two returns policies

To avoid stockouts and maintain product availability, retailers typically carry excess units and subsequently incur higher cost. In case of style/fashion goods, demand forecasting is extremely difficult due to short selling cycles. The purpose of this study was to minimise the cost of excess stocking without compromising product availability. To achieve these conflicting objectives, our study includes two ordering instances and two returns policies. The time between orders subsequently helps resolve demand uncertainty. Existing studies consider only one type of returns policy, that is, returns on the entire purchase quantity; whereas our study considers two types of returns policies: returns on the first order size and returns on the entire purchase quantity. This study also includes models for the retailer and the supply chain system. Analytical and numerical insights into our study enable the retailer to select his appropriate returns policies to maximise his as well as system’s expected profits. We also show that perfect coordination of partners will help them improve their profits considerably.