供应链融资模式下零售商的订货与定价研究

已有零售商订货与定价问题的研究大都忽略了零售商的初始资金,本文在考虑零售商初始资金的情况下,研究零售商面对初始资金不足时,如何借助外部的融资政策做出最优的订货与定价决策.因此,本文分别讨论了零售商在无融资服务,供应链中核心制造商担保下的外部融资服务及核心制造商提供商业信用的内部融资服务下的订货与定价问题,并建立了相应的...     

The influence of financial conditions on optimal ordering and payment policies under progressive interest schemes

In many business-to-business transactions, the buyer is not required to pay immediately after the receipt of an order, but is instead allowed to postpone the payment to its suppliers for a certain period. In such a situation, the buyer can either settle the account at the end of the credit period or authorize the payment later, usually at the expense of interest that is charged by the supplier on the outstanding balance. Some payment terms, which are often referred to as trade credit contracts, contain progressive interest charges. In such cases, the supplier offers a sequence of credit periods, where the interest rate that is charged on the outstanding balance usually increases from period to period. If a buyer faces a progressive trade credit scheme, various options for settling the unpaid balance exist, where the financial impact of each option depends on the current credit interest structure and the alternative investment conditions. This paper studies the influence of different financial conditions in terms of alternative investment opportunities and credit interest structure on the optimal ordering and payment policies of a buyer on the condition that the supplier provides a progressive interest scheme. For this purpose, mathematical models are developed and analyzed.     

On certain optimal gas storage policies

A gas distribution company must satisfy at every instant of time an exogenous demand. In order to meet the peak demand in the most economic way, it can resort to storage and peak shaving techniques. For the case of a local distribution company linked to a national gas grid through a connection of bounded transmission capacity, we derive a schedule of drawing gas from the national grid that minimizes the storage capacity required under the assumption of deterministic demand. The storage minimizing schedule is derived through both elementary and optimal control methods. An extension is possible for the case of stochastic demand.     

Optimal production,replenishment, delivery,routing and inventory management policies for products with perishable inventory

This paper presents a generalized production-inventory-routing model with perishable inventory. We analyze the optimal integrated decisions of when and how much to deliver and sell products with varying manufacturing periods. We discuss main inventory management policies to demonstrate the applicability of the model in real-world applications for production routing problems (PRPs) with perishable inventory. Furthermore, an exact branch-and-cut algorithm is developed and discussed. We introduce new families of logical, strengthened lot-sizing and lifted Miller–Tucker–Zemlin subtour elimination constraints for the PRP with perishable inventory. Finally, we test the performance of the algorithm. We also implement and compare 8 suboptimal delivery and selling priority policies with an optimized policy to develop managerial implications.     

On threshold BDDs and the optimal variable ordering problem

Many combinatorial optimization problems can be formulated as 0/1 integer programs (0/1 IPs). The investigation of the structure of these problems raises the following tasks: count or enumerate the feasible solutions and find an optimal solution according to a given linear objective function. All these tasks can be accomplished using binary decision diagrams (BDDs), a very popular and effective datastructure in computational logics and hardware verification. We present a novel approach for these tasks which consists of an output-sensitive algorithm for building a BDD for a linear constraint (a so-called threshold BDD) and a parallel AND operation on threshold BDDs. In particular our algorithm is capable of solving knapsack problems, subset sum problems and multidimensional knapsack problems. BDDs are represented as a directed acyclic graph. The size of a BDD is the number of nodes of its graph. It heavily depends on the chosen variable ordering. Finding the optimal variable ordering is an NP-hard problem. We derive a 0/1 IP for finding an optimal variable ordering of a threshold BDD. This 0/1 IP formulation provides the basis for the computation of the variable ordering spectrum of a threshold function. We introduce our new tool azove 2.0 as an enhancement to azove 1.1 which is a tool for counting and enumerating 0/1 points. Computational results on benchmarks from the literature show the strength of our new method.     

On the optimality of the optimal policies for the deterministic EPQ with partial backordering

In a note published in Omega [Zhang RQ. A note on the deterministic EPQ with partial backordering. Omega 2009;37(5):1036–8], the amended decision procedure for the Pentico et al.'s EPQ with partial backordering (EPQ-PBO) is proposed, by developing another critical value of the backordering rate. However, there is a case when a decision made with this amended procedure is not optimal, which will be shown in this paper. A new decision procedure will be proposed based on the derived necessary and sufficient conditions for considering the policy of losing all sales or the policy to meet all demand as possible optimal decisions. The proposed decision procedure is adapted for one of the extensions of the EPQ-PBO.     

Risk tolerance and a retailer's pricing and ordering policies within a newsvendor framework

This paper evaluates the pricing and ordering policies of a retailer, facing a price-dependent stochastic demand, within a newsvendor framework, under different degrees of risk tolerance and under a variety of optimizing objectives. These are (i) maximizing expected profit, for a retailer who may be risk-seeker, risk-averse or risk neutral; (ii) deriving a maximin strategy of maximizing a minimum guaranteed profit and (iii) modeling the probability of exceeding a target profit, as a constraint or as an objective. Some analytical properties and numerical examples illustrate the main features of the models and provide some comparative policy analysis across the model.     

Competitive markdown timing for perishable and substitutable products

We model as a duopoly two firms selling their fixed stocks of two substitutable items over a selling season. Each firm starts with an initial price, and has the option to decrease the price once. The problem for each firm is to determine when to mark its price down in to maximize its revenue. We show that the existence and characterization of a pure-strategy equilibrium depend on the magnitude of the increase in the revenue rate of a firm when its competitor runs out of stock. When the increase is smaller than the change in the revenue rate of the price leader when both firms are in stock for all of the three possible scenarios, neither firm has the incentive to force its rival to run out of stock and if a firm marks its price down after the season starts, its inventory runs out precisely at the end of the season. When the increase is larger than the change of the price leader׳s revenue rate in one particular scenario, waiting until its rival runs out of inventory may be an equilibrium strategy for the larger firm even though this may lead to leftover inventory for itself. In other cases, there may be no pure-strategy equilibrium in the game. In certain regions of the parameter space, a firm׳s revenue may be decreasing in its starting inventory which shows that a firm may be better off if it can credibly salvage a portion of its inventory prior to the game. While most of our analysis is for open-loop strategies, in the final part of the paper, we show that the open-loop equilibrium survives as an equilibrium when we consider closed-loop strategies for an important subset of the parameter space.     

A flexible model for the pricing of perishable assets

We present a flexible and versatile model which addresses the problem of assigning optimal prices to assets whose value becomes zero after a fixed expiry date. (Such assets include the important example of seats on airline flights.) Our model is broad in scope, in particular encompassing the ability to deal with arrivals of customers in groups. It is highly adaptable and can be adjusted to deal with a very extensive set of circumstances.Our approach to the problem is based on elementary and intuitively appealing ideas. We model the arrival of customers (or groups of customers) according to an inhomogeneous Poisson process. We incorporate into the model time dependent price sensitivity (which may also be described as “time dependent elasticity of demand”). In this setting the solution to the asset pricing problem is achieved by setting up coupled systems of differential equations which are readily amenable to numerical solution via (for instance) a vectorised Runge-Kutta procedure. An attractive feature of our approach is that it unifies the treatment of discrete and continuous prices for the assets.     

季节性易逝品预售与回购联合决策研究

基于季节性易逝品短销售期和短保质期的“双短”特性,其高额利润通常伴随着较大需求不确定性,而且一旦错过销售季节,其极低的残值将导致巨大经济损失与资源浪费.折价预售策略将鼓励消费者提前购买,经销商也可通过预售产品数量的获知来提升市场需求预测的准确性.但消费者在享受预购折价优惠的同时,也可能承担未见到实物产品即进行购买的期望价值损失.此时,经销商若采取回购,则是对消费者利益的直接保障,而在产生回购成本的同时,也可以通过提高预售价格与降低实物订货量等方式带来新增利润.考虑策略型消费者行为,对预售与回购联合策略和单一预售策略进行对比,构建两种策略下的经销商收益模型,并得出相应的最优预售价格与最优订购量.研究发现,当商品单位成本较大或回购价格较低时,预售与回购联合策略的实施能够使经销商获得更优收益,且最优预售价格高于单一预售策略,最优订货量则低于单一预售策略,从而为经销商营销策略选择进行决策支持.     

需求信息更新条件下易逝品的批量订货策略

为了获得价格折扣或运输方便,制造商常常要求零售商采取批量订货的策略.文章研究考虑顾客需求信息更新的易逝品的批量订货策略.制造商通过为零售商提供两次订货机会,来实现制造商和零售商的共赢.通过对开始时刻和顾客需求信息更新后的系统进行建模和讨论,得到了在两次订货条件下零售商应该采取的优化的订货与调整策略.     

易腐性产品运输设施选择博弈

易腐性产品的价值会随着时间的流逝而逐渐损失,多个客户可以联合使用某种运输设施时,如何对费用进行公平且稳定的分摊是合作能否进行的基础.把易腐性产品的损失价值和运输费用之和作为总费用,进而将易腐性产品的运输设施选择的费用分配问题构造成运输设施选择合作博弈,证明了在易腐性产品负指数价值损失的情况下,运输设施选择博弈的核心非空,且为凹博弈,并讨论了解的特征.论文还证明具有附加运输费用的运输设施选择博弈的核心非空,分析了核心与线性规划松弛的对偶最优解之间的关系.论文对有约束设施选择博弈进行了分析,并提出了进一步研究的方向.     

易逝性高科技产品收益管理定价策略

高科技产品作为一种典型的易逝性商品,其定价对于零售商的利润有着举足轻重的影响.基于收益管理思想,以获得最大期望利润为目标,考虑缺货时消费者的替代行为,建立了随机需求环境下基于多项logit顾客选择模型和服务水平的易逝性高科技产品收益管理定价策略模型.对建立的模型用单阶段算例进行了模拟分析,并讨论了不同顾客到达率、不同初始库存、产品对于消费者的不同影响度下的最优策略,得出了一系列比较有意义的性质和管理原则.     

A stochastic programming model for production planning of perishable products with postponement

This study addresses the production planning problem for perishable products, in which the cost and shortage of products are minimised subject to a set of constraints such as warehouse space, labour working time and machine time. Using the concept of postponement, the production process for perishable products is differentiated into two phases to better utilise the resources. A two-stage stochastic programming with recourse model is developed to determine the production loading plan with uncertain demand and parameters. A set of data from a toy company shows the benefits of the postponement strategy: these include lower total cost and higher utilisation of resources. The impact of unit shortage cost under different probability distribution of economic scenarios on the total cost is analyzed. Comparative analysis of solutions with and without postponement strategies is also performed.     

考虑竞争者进入威胁的易逝品动态定价机制

本文研究了同时考虑竞争者进入威胁和消费者行为的易逝品的动态定价机制.依据策略性和忠诚性两个维度,将市场中的消费者分为策略型忠诚者、策略型转换者、短视型忠诚者和短视型转换者四种类型.建立了在位企业、竞争企业与策略消费者间的两阶段动态博弈模型,通过均衡求解与分析,探讨了在位企业和竞争企业的最优价格机制以及消费者行为对企业定价行为和均衡收益的影响,深入分析了竞争者的进入行为对在位企业定价和收益的影响,以及消费者策略行为和转换行为与竞争者进入行为间的交互作用机制.研究表明:在位企业可以依据策略消费者的比例,采取智能的动态定价机制,实行或放弃对策略消费者的跨期价格歧视,最大化自身收益;消费者策略行为会降低在位企业的绩效却能够提高竞争者的绩效;竞争者的进入并非总是对在位企业不利,在一定条件下,竞争者的进入有利于提高在位企业的绩效;在位企业通过多种方式培养自己的忠实顾客,不仅能够应对竞争者的进入威胁而且能够缓解消费者策略行为的负面影响.     

两种订货模式下订购和促销联合优化策略

本文基于CVaR决策准则,通过构建需求依赖于促销的一般需求模型,其中包括加法和乘法需求模型作为特例,考察了一次订货和允许紧急订货两种模式下风险厌恶零售商关于促销和库存的联合优化问题。讨论了紧急订购成本、风险厌恶以及市场需求变动对最优策略的影响,并对两种模式下零售商的最优策略和收益进行了比较分析,结果表明:在两种订货模式下,零售商的最优订购量和促销努力均随风险厌恶程度的增大而降低;紧急订货模式下的促销努力和实现的收益大于一次订货模式,且在加法需求模型下,紧急订货模式下的初次订购量小于一次订货模式的最优订购量。运用随机变量一阶和二阶交替随机占优的概念刻画了市场需求变动下零售商如何调整最优策略的充分条件。最后实施数值实验验证了理论分析结果。     

Multidimension scaling for multiobjective policies

This paper develops and expands the use of multidimension scaling techniques (MDSCAL) as applied in the two separate fields of psychological testing and archaeology to the problem of multiple criteria decision making. Other work by the author published elsewhere shows that it is feasible to use MDSCAL for drawing maps of separate policies using very weak input information from which deductions as to most preferred and least preferred policies may be drawn. An application of this method is made, to show its use and a comparison made with the utility approach. The final, and main, part of the paper examines the robustness of the method for both deterministic and probabilistic input criteria. In this examination it is seen that the mapping method performs very well in picking up extremes of preference even under severe tests of robustness.     

A dynamic product quality evaluation based pricing model for perishable food supply chains

Waste stemmed from inappropriate quality control and excessive inventories is a major challenge for perishable food management in grocery retail chains. Improvement of visibility and traceability in food supply chains facilitated by tracking and tracing technologies has great potential to improve operations efficiency. This research aims to reduce food spoilage waste and maximise food retailer's profit through a pricing approach based on dynamically identified food shelf life. The proposed model is evaluated through different pricing policies to exploit the benefits from utilising accurate product shelf life information captured through innovated tracking and monitoring technologies. Numerical analysis is conducted in an illustrative case study.     

易逝性高新技术产品在衰退期的收入管理问题

通过对处于衰退期的高新技术产品的分析,指出高新技术产品的易逝性现象,并将收入 管理原则运用于衰退期中高新技术产品的价格策略. 针对此类产品的易逝性和需求的随机 性,提出对价格和生产规模进行综合控制的数学模型并给出求解的方法. 算例表明,使用收入 管理方法可以显著提高销售收入,增加企业经济效益.