An algorithm for solving the multi-period online fulfillment assignment problem

This paper develops an optimal solution procedure for the multi-period online fulfillment assignment problem to determine how many and which of a retailer/e-tailer’s capacitated regional warehouse locations should be set up to handle online sales over a finite planning horizon. To reduce the number of candidate solutions in each period, dominance rules from the facility location literature are extended to handle the nonlinear holding and backorder cost implications of our problem. Computational results indicate that multi-period considerations can play a major role in determining the optimal set of online fulfillment locations. In 92% of our test problems, the multi-period solution incorporated fewer openings and closings than myopic single period solutions. To illustrate the use of the model under changing demands, the multi-period solution yielded different supply chain configurations than the myopic single period solution in over 37% of the periods.     

蔬果类商品网上直销包装作业工序优化模型研究

针对蔬果类商品网上直销模式下,其标准销售单元包装作业问题规模大、商品品类多、订单个性化强、生产配送周期多等特点,基于批量流水作业生产、JIT准时制生产及周期调度的思想,研究该类商品标准销售单元包装作业的生产调度问题,建立蔬果类商品网上直销包装作业优化模型,并设计改进的“模拟增压——退火算法”对其进行求解,以便制定出合理的包装作业计划,有效衔接采摘和订单分拣作业以及后续装车作业,缩短包装时间,保证蔬菜的新鲜性。最后,通过应用实例验证模型和算法的有效性,结果表明,本文周期调度方法得到的调度方案比一般的非周期调度方法大大节约了包装作业成本,为蔬果类商品网上直销企业生成包装作业计划提供了理论指导。     

双渠道模式下制造商线上定制策略研究

本文针对制造商在传统零售渠道和线上网络渠道同时销售标准产品的情况下,是否应该开放线上定制策略的相关问题进行分析。首先通过圆形市场模型完成市场划分;其次,在制造商不开放线上定制策略和开放线上定制策略两种情况下分别构建制造商和零售商利润最大化模型,得到了两种情况下的市场均衡结果。通过分析和比较两种情况下制造商和零售商的最优决策结果发现,当标准产品的边际生产成本较大且开放线上定制策略的成本较小时,制造商应该开放线上定制策略;制造商开放线上定制策略后,会使标准产品的批发价格和零售价格增加,并削弱零售商的利润;定制产品的生产成本越高,制造商开放定制产品的动机越小;消费者对标准产品的适应成本越高,制造商开放定制产品的动机越大。     

基于预售的生鲜供应链销售模式选择与定价研究

研究预售下由供应商与零售商构成的生鲜供应链的销售模式选择与定价策略,其中包括分散与集中两种销售模式,撇脂与渗透两种定价策略。结果表明,在网络消费者对实体渠道偏好较低时,分散与集中模式均会选择撇脂定价,反之选择渗透定价。撇脂定价下,集中模式中零售商可以通过调节两个渠道的价格占有更大的市场,获取高于分散模式下的利润。而分散模式中,由于两个零售商会存在竞争,因此为了获得竞争优势该模式下的定价会存在低价销售的情形。比较销售模式可知,在网络消费者占比少或占比多但对实体渠道偏好越小时,供应商在分散模式下能获得更高的利润,反之,集中模式对供应商更有利。但是,对零售商而言,分散模式更有利于实体渠道,而集中模式更有利于网络渠道。     

基于企业网络舆情的客户满意度分析及管理方法

社交网络平台的迅速发展,促使网络舆情成为企业获取商业情报、扩大竞争优势的重要信息来源。本文针对网络舆情环境下的企业客户关系管理问题展开研究。通过构建企业客户推动式信息反馈模型,描述了企业客户、网络用户与企业网络舆情间的联系,并依据信息反馈模型,提出变尺度聚类算法。该算法将传统聚类方法的求解过程由单一尺度分析扩展到多尺度分析,克服了实际数据聚类应用过程中的聚类结果特征不显著问题。本文选取新浪微博作为数据源,利用企业网络舆情数据集和企业客户数据集进行数据分析实验。实验结果表明,企业可以通过获取与其主营业务相关的网络舆情信息,实现客户满意度预测;同时,变尺度聚类算法结果能够为企业进一步制定销售战略和销售战术提供决策支持。     

考虑平台优惠券的不同线上销售决策研究

本文以第三方电商平台是否发放优惠券和线上销售商是否进行集成销售(现售与预售并存)为标准构建四种Stackelberg模型,分析了平台佣金率、商品估值差异系数以及优惠券兑换率对供应链成员的决策与利润影响。结果表明,随着佣金率的提高,商品(现售和预售)的销售价及优惠券面值也随之增加;当预售成本足够低时,开展预售活动以及缩小估值差异可以提高线上销售商的收益;在一定条件下,提高优惠券兑换率可以增加供应链成员的收益,电商平台发放优惠券使其收益增加,却损害了销售商利润;相比其他销售方案,供应链系统利润在集成销售方案下最优。     

考虑无缺陷退货的在线商品信息发布策略

消费者网络购物面临的不确定性往往导致非质量原因的退货。合理发布产品信息,并提供退货保障,是网络零售商促进消费者购买和提高利润的有效策略。基于消费者效用理论和博弈论,构建了产品信息影响消费者购买和退货模型,研究了零售商在垄断和竞争情形下的产品信息发布决策问题,发现垄断性零售商的最优信息发布策略和竞争性零售商在发布产品信息量和信息内容方面的均衡策略均取决于产品价值和退货成本特征,提出了不同市场结构下基于产品特征的在线商品信息发布策略。     

Distributed Online Frequency Assignment in Cellular Networks

A cellular network is generally modeled as a subgraph of the triangular lattice. The distributed online frequency assignment problem can be abstracted as a multicoloring problem on a weighted graph, where the weight vector associated with the vertices models the number of calls to be served at the vertices and is assumed to change over time. In this paper, we develop a framework for studying distributed online frequency assignment in cellular networks. We present the first distributed online algorithms for this problem with proven bounds on their competitive ratios. We show a series of algorithms that use at each vertex information about increasingly larger neighborhoods of the vertex, and that achieve better competitive ratios. In contrast, we show lower bounds on the competitive ratios of some natural classes of online algorithms.     

Inventory and sales effort management under unobservable lost sales

A retailer needs to make decisions regarding how much to order and how much sales effort to exert in an environment with uncertain demand. One intrinsic complexity in a typical retail environment is caused by the fact that the retailer can obtain information about demand only based on sales, as demand itself is unobservable. Taking a Bayesian approach, Lariviere and Porteus (1999) show that in such a setting a retailer should stock more to increase the probability of an exact demand observation. In this article, we extend their work by allowing the retailer to control both the stocking quantity and sales effort, which can be used to affect demand. We show that their insights with respect to information stalking carry over to this setting. In addition, our model allows gaining a better understanding of optimal sales effort strategies. We find that demand management has a dual role in supporting information gathering: while at the beginning of a product life cycle it is optimal to support learning effects by sharply reducing sales effort, at later stages of the product life cycle an aggressive strategy of increased promotional activities can be used to harvest the information gathered in earlier periods.     

Entry of online presale of fresh produce: A competitive analysis

The fresh produce market is one of the last unexplored spaces for e-commerce and has attracted the entrance of many e-commerce firms in recent years; these firms are likely to influence the traditional fresh produce sales channels. The online presale of fresh produce can lower the circulation loss rate while traditional sales channels suffer from a huge waste in the circulation. In this paper, we study the online presale model of fresh produce from a competitive perspective. We examine the pricing and order decisions of one online grocery and one physical store. By examining the physical store with and without the online grocery, we investigate the impact of the entry of an online grocery on the physical store. We first identify two pricing strategies, penetration-pricing and skimming-pricing, for the physical store and two pricing strategies for the online grocery, and then identify the conditions under which pricing equilibrium will occur. We find that the store does not necessarily alter its pricing strategy after the online grocery enters the market. When the physical store uses the penetration-pricing strategy to compete with the online grocery for Internet shoppers, it may fail to achieve that goal if the online grocery's delivery cost is low and if the Internet shoppers account for a relatively low proportion of shoppers. Alternatively, the physical store may fail if the online grocery's delivery cost is not high and if the circulation loss rate of fresh produce is high.     

基于在线评论的多个竞争制造商和零售商的产品定价策略

在线评论作为一种产品信息传播载体,越来越受到网上电商及消费者的重视,并在很大程度上影响消费者的购买决策。本文在多个竞争性制造商为在线零售商提供可替代性产品并通过零售商销售给网络消费者的电子商务环境下,研究在线评论信息如何影响网络消费者购买决策及在线零售商和制造商的定价策略。以neo-Hoteling模型为基础,构建了依赖零售渠道在线评论的消费者选择模型,并通过模型求解定量分析了二级供应链结构分散系统下在线评论对多个竞争性制造商及零售商最优决策的影响。得到当制造商基于评论制定最优定价策略时,在线评论对市场竞争强度没有影响,但决定潜在市场大小;各产品的均衡批发价及销售价按一定的比例随评论揭示的该产品与其他产品质量均值之差(正或负)增加或减少,评论信息通常会使制造商因好评而获利,由于评论增加了不同产品需求的不对称性,零售商因而具有更大的调价空间,往往通过提高(降低)占据有利(不利)评论的产品价格获得更高的利润。     

Conditional lexicographic orders in constraint satisfaction problems

The lexicographically-ordered CSP (“lexicographic CSP” or “LO-CSP” for short) combines a simple representation of preferences with the feasibility constraints of ordinary CSPs. Preferences are defined by a total ordering across all assignments, such that a change in assignment to a given variable is more important than any change in assignment to any less important variable. In this paper, we show how this representation can be extended to handle conditional preferences in two ways. In the first, for each conditional preference relation, the parents have higher priority than the children in the original lexicographic ordering. In the second, the relation between parents and children need not correspond to the importance ordering of variables. In this case, by obviating the “overwhelming advantage” effect with respect to the original variables and values, the representational capacity is significantly enhanced. For problems of the first type, any of the algorithms originally devised for ordinary LO-CSPs can also be used when some of the domain orderings are dependent on assignments to “parent” variables. For problems of the second type, algorithms based on lexical orders can be used if the representation is augmented by variables and constraints that link preference orders to assignments. In addition, the branch-and-bound algorithm originally devised for ordinary LO-CSPs can be extended to handle CSPs with conditional domain orderings.     

Eigenstructure assignment for linear parameter-varying systems with applications

The aim of this paper is to show that a recently proposed technique for eigenstructure assignment of linear time-invariant systems can be extended to solve the corresponding eigenstructure assignment problem for linear parameter-varying systems, whose state-space matrices depend on a set of time-varying parameters that are bounded and available online. In particular, the design of eigenstructure assignment is performed without requiring any conditions on the closed-loop eigenvalues, and provides a simple, complete and analytical parametric approach as well as the most degrees of design freedom for the eigenstructure assignment problem of linear parameter-varying systems. A parameter-varying attitude control system of refueling spacecraft in-orbit is used to demonstrate the usefulness and practicality of the proposed approach.     

Interactions of competing manufacturers’ leader-follower relationship and sales format on online platforms

Currently, manufacturers can sell products on e-tailers’ online platforms through agency sales format or reselling format. However, how to choose the best sales formats has puzzled competing manufacturers in practice. The main purpose of this paper is to answer this problem by considering the combined effects of manufacturers’ leader-follower relationships, the e-tailer’s referral fees, the difference in products’ substitutable degrees and the difference in products’ market bases. Our results show that, if demand functions are linearly price-dependent, when two manufacturers sell substitutable products on the same e-tailer’s online platform, the e-tailer’s best action is always to let both manufacturers adopt reselling format; regardless of one manufacturer’s sales format, the other manufacturer always prefers agency sales format, which are independent of the e-tailer’s referral fees, the difference in two products’ substitutable degrees and the difference in two products’ market bases. Whether demand functions are linear or nonlinear in retail prices, the e-tailer’s best action is to let both manufacturers whose products are symmetric adopt reselling format; no matter what sales format one manufacturer adopts, the other manufacturer always prefers agency sales format, which are independent of the two manufacturers’ leader-follower relationships. Moreover, if two manufacturers adopt same sales format to sell symmetric products, leader role enables a manufacturer to charge higher optimal wholesale/retail price when demand functions are linear in retail prices, but the two products have equal optimal wholesale/retail prices regardless of the two manufacturers’ leader-follower relationships when demand functions are nonlinear in retail prices.     

网络平台零售商自主销售对平台定价策略的影响

网络平台零售商为了应对愈发激烈的市场竞争,获取更高的利润,选择进入零售市场自主销售。本文在制造商和网络平台零售商构成的渠道结构下,研究网络平台零售商进入市场自主销售对渠道成员的利润、销量以及定价策略的影响。结果显示,网络平台零售商自主销售会带来积极的溢出效应。当竞争系数足够大时,(1)渠道成员的利润均会得到提升,且市场竞争越激烈渠道成员的利润提升越显著;(2)网络平台零售商会提高平台费,渠道成员也会制定更高的零售价格。更为重要的是,网络平台零售商自主销售模式下,渠道的总体利润得到提升,存在帕累托改进。     

Efficient shift scheduling in the retail sector through two-stage optimization

Efficient workforce scheduling has an important impact on store profit and customer service. Standard scheduling problems do not recognize the effect of staff availability on customer sales, however, even though the latter is an important factor in the retail sector. In this paper a two-stage model is proposed for this purpose. In the first stage a sales response model is used to specify hourly staff requirements. The output of the sales response model is then used as the input of a mixed integer optimization model, which finds an optimum assignment of the staff to daily shifts. Simulations are used to validate the sales response function, and to revise the model for more accurate results. In the simulations, customer arrivals and sales response error values are generated using appropriate distribution functions. As a case study the proposed model is applied to a Turkish retailer in the apparel sector.     

考虑网络外部性的生鲜企业渠道选择策略研究

考虑到生鲜产品容易变质而且线上配送时间较长,并且线上销售可为消费者带来额外网络外部性,传统生鲜企业在电商冲击的背景下需要考虑是否入驻电商平台开拓线上业务。为解决此类企业所面临渠道选择问题,本文考虑一个传统生鲜企业和一个主导电商市场的电商平台,并通过构建理论模型研究企业最优生鲜产品定价和渠道选择策略。研究结果表明,若平台所收取年服务费较低,则企业应入驻平台;反之,企业不应入驻平台。此外,消费者网络外部性敏感程度对企业入驻平台行为具有正影响。在拓展模型,本文考虑分散式供应链情形下企业最优渠道选择,结果表明相较于集中式决策,分散式供应链情形下零售商更不愿意入驻平台。此外,本文通过设计收益共享契约以协调生鲜企业与电商平台,并发现通过契约协调,零售商更愿意入驻电商平台。     

基于线上评论的生鲜产品供应链定价策略

随着网络购物的普及,线上评论对消费者的购买决策发挥着越来越重要的作用,零售商和制造商可以利用这些评论调整、优化生产流程。本文基于消费者效用理论,构建了由一个零售商和一个制造商组成的生鲜产品供应链定价决策模型,研究了三种决策模式下生鲜产品零售价、利润和保鲜努力水平的差异。研究发现:集中决策下生鲜产品的最优零售价最低、利润最高;随着运输时间增加,保鲜努力水平和新鲜度均呈现下降趋势;当成本分担系数较高时,在成本分担和收益共享的分散决策模式下,保鲜努力最优水平高于集中决策模式下保鲜努力最优水平。     

A real-time decision rule for an inventory system with committed service time and emergency orders

In this paper, we study the inventory system of an online retailer with compound Poisson demand. The retailer normally replenishes its inventory according to a continuous review (nQ, R) policy with a constant lead time. Usually demands that cannot be satisfied immediately are backordered. We also assume that the customers will accept a reasonable waiting time after they have placed their orders because of the purchasing convenience of the online system. This means that a sufficiently short waiting time incurs no shortage costs. We call this allowed waiting time “committed service time”. After this committed service time, if the retailer is still in shortage, the customer demand must either be satisfied with an emergency supply that takes no time (which is financially equivalent to a lost sale) or continue to be backordered with a time-dependent backorder cost. The committed service time gives an online retailer a buffer period to handle excess demands. Based on real-time information concerning the outstanding orders of an online retailer and the waiting times of its customers, we provide a decision rule for emergency orders that minimizes the expected costs under the assumption that no further emergency orders will occur. This decision rule is then used repeatedly as a heuristic. Numerical examples are presented to illustrate the model, together with a discussion of the conditions under which the real-time decision rule provides considerable cost savings compared to traditional systems.     

考虑零售商销售努力的制造商入侵策略研究

渠道入侵正逐渐成为企业开拓市场,实现多渠道销售的重要策略。在考虑零售商销售努力的前提下,研究了制造商渠道入侵策略。构建了四种Stackelberg博弈模型:不入侵和无销售努力、入侵和无销售努力、不入侵和有销售努力、入侵和有销售努力。研究结果表明,线上直销渠道与线下零售渠道之间的不对称替代水平越高,越不利于制造商入侵;在制造商入侵的情况下,零售商销售努力促使制造商降低批发价格;渠道入侵成本较大且零售商销售努力投资效率高的前提下,销售努力可以有效缓解制造商入侵带来的负面影响;渠道入侵降低了零售商销售努力的动机。