区分仓库与货架库存需求影响效应的零售商库存决策

既往有关库存水平影响需求条件下的库存问题研究中,通常对终端库存水平是否存在货架与零售商仓库库存水平的区别未作深入探讨。本文的研究认为,现实中许多零售商拥有仓库,其现有库存水平包括仓库库存和货架库存两部分,而影响需求的仅为与货架展示能力相关的库存,因此有必要对二者的需求影响效应进行区分。在明确这一区别的前提下,本文首先建立了供应商管理库存情况下库存水平影响需求问题的一般库存模型,给出零售商的最优订货策略;并考虑货架的容量限制,给出零售商启用仓库的判断条件。由于仓库库存仅在能够影响货架展示能力的条件下才能够影响消费需求,本文还进一步讨论了在零售商拥有仓库时,区分货架与仓库的库存水平影响需求条件下的最优库存与订货决策。这对于经营不同特征商品的零售商在进行是否需要拥有仓库,以及拥有仓库条件下的库存决策具有很好的参考价值。     

供应链库存分散决策研究

本文研究两级供应链库存问题,供应链包含一个客户和一个生产商.通过建立客户订货库存模型和生产商生产库存模型得到供应链库存模型.采用分散决策方法获得最优解,即最佳订货量和最佳订货次数.在此基础上,使用算例对最优解进行了数值分析.     

基于新鲜度的冷链一体化库存与定价联合决策

为了揭示生鲜农产品在流通中质量与数量损耗的变化规律,分析"双重损耗"对冷链库存的影响,针对配送中心与零售商组成的两级冷链系统,引入保鲜努力与时间因素对生鲜农产品的数量与质量损耗进行刻画,尤其突显了二者间的关联性及其合理性,需求上综合考虑了价格与新鲜度的影响,以供应链总平均利润最大化为目标函数,建立了二级冷链一体化库存模型,并对系统最佳的保鲜投入、库存及定价进行了规划求解。随后,以某连锁超市销售的鲜切果蔬为例进行仿真,验证了模型的有效性。最后,灵敏度分析发现,一方面,系统利润会随着新鲜度时间敏感性的降低与保鲜努力敏感性的增加而增加,且时间敏感因子更容易左右系统利润的变化。另一方面,并非所有的生鲜农产品都适用打折促销。考虑商品"双重损耗"所做的库存与定价的优化分析不仅为生鲜农产品冷链的理论研究提供了新思路,也为冷链运作实践提供了更为可靠、更为有效的决策参考。     

价格波动的可控性

本文研究了如何提出合理的预期价格,保证供给和需求趋于均衡,从而实现价格波动的可控性。     

随机型库存系统的基本决策

本文根据随机型库存系统的特点建立原料库存模型,并分析比较了两种不同决策方法的优劣,以此获得最优订货点和最优订货批量     

浅析甲醇库存和价格的关系

目前,甲醇市场变化快,价格波动幅度大,影响因素多,且无法落地,只能封闭库存,因此库存控制对于甲醇销售来讲非常重要。本文通过科学分析甲醇库存与价格的关系,提出在不同市场环境下,甲醇价格制定与库存控制的相关建议,以使公司抓住市场机遇、规避市场风险,实现利润最大化,进而加强调控市场的能力。     

价格柔性合同下的原材料采购策略及风险分析

为了降低原材料价格波动给采购-供应双方企业带来的风险,供应链企业通常采用签订价格合同的方式来共同分担原材料价格波动的风险。本文通过设计价格柔性合同,利用Stackelberg主从博弈模型研究了由一个供应商和一个制造商组成的采购系统的最优采购策略及原材料价格波动风险的分担机制。研究表明,通过实施价格柔性合同可以降低供应双方的风险,且通过设置合理的价格柔性系数可以提高双方的收益。     

物料价格随时间波动及完工期随机的MTO订购决策

对于订单式中小生产企业,物料供应是否及时以及生产进度是否按计划进行是影响订单交货期的关键因素。实际中,某些产品的物料价格随时间连续波动并具有规律性,而生产过程中由于插单多、工人流动性大、设备故障、质量返工等,生产完工期有一定的随机性。对于物料订购决策,传统方法主要考虑订单的投产日期以及物料采购成本最小化,而未考虑订单完工期的随机性特点。基于企业内部供应链集成及总成本最小化的系统思想,综合考虑物料价格的变化趋势以及随机生产完工期的统计规律,分别建立单一物料或多种物料订购情形下总生产成本(包括订购成本、制造成本、延迟完工或提早完工成本等)与订购日期的关系模型,并对其最优解进行讨论、分析与求解。当物料种类单一时,采用极值法对模型极小值点的存在性进行讨论;当物料种类较多时,构建了有约束条件的多决策变量非线性优化模型,并采用最优化理论中的拉格朗日乘子法(即PHR算法)进行求解。通过实例分析,得出的结论是物料最佳订购时间点与物料初始价格、价格波动周期、波动幅度、单位延迟或提早完工成本等因素相关。上述采购与生产集成的思想、模型构建的思路以及求解方法等可供有关人员参考。     

双渠道下库存与定价策略的研究

为分析实体店零售商建立自己网络渠道存在的两个基本问题,本文探讨了为满足网络渠道需求网络渠道是自持有库存、还是共享实体店的库存问题,及如何解决网络渠道与实体渠道的销售冲突问题。在总结动态库存配给策略相关研究基础上,采用了动态定价策略的思路分析解决渠道冲突的问题;通过对双渠道是否共享库存的两种方案进行模拟对比,分析讨论了相关库存决策问题,并评价了共享库存所带来的共享效应的大小,以期使实体店零售商建立网络销售渠道取得更大的收益。研究结果表明,共享库存有比较显著的优势,库存共享效应能使需求波动更平滑、需求预测更精准;动态定价会带来更大的收益,在验证该结果时,对动态定价策略也进行了结构特征的分析。该思路可为相关研究提供借鉴。     

船舶机械企业采购及库存管理策略分析

采购与库存管理是企业经营管理和生产运作管理中的一个十分重要的问题，直接影响了企业的经营效益，因此采用合理的采购与库存策略十分重要，本文针对某一船舶机械厂的采购与库存管理策略进行分析，将所需物料分为三类，再针对每类物料不同的特点采用不同的采购和库存策略。     

Changing risk preferences in supply chain inventory decisions

The risk preferences of managers may cause their inventory ordering decisions to deviate from the optimal policy. Past studies in operations management have produced mixed results. This study examines this proposition using decision data collected from a supply chain experiment. This article finds that changing the risk preferences of managers with respect to demand changes and supplier failures is a significant behavioural factor in explaining deviations in ordering decisions. This result provides an additional behavioural cause in explaining the bullwhip effect in supply chains. It also provides insights on the challenges for reducing the bullwhip effect in supply chains.     

Joint modified block replacement and production/inventory control policy for a failure-prone manufacturing cell

This paper considers a joint preventive maintenance (PM) and production/inventory control policy of an unreliable single machine, mono-product manufacturing cell with stochastic non-negligible corrective and preventive delays. The production/inventory control policy, which is based on the hedging point policy (HPP), consists in building and maintaining a safety stock of finished products in order to respond to demand and to avoid shortages during maintenance actions. Without considering the impact of preventive and corrective actions on the overall performance of the production system, most authors working in the reliability and maintainability domains confirm that the age-based preventive maintenance policy (ARP) outperforms the classical block-replacement policy (BRP). In order to reduce wastage incurred by the classical BRP, we consider a modified block replacement policy (MBRP), which consists in canceling a preventive maintenance action if the time elapsed since the last maintenance action exceeds a specified time threshold. The main objective of this paper is to determine the joint optimal policy that minimizes the overall cost, which is composed of corrective and preventive maintenance costs as well as inventory holding and backlog costs. A simulation model mimicking the dynamic and stochastic behavior of the manufacturing cell, based on more realistic considerations of the real behavior of industrial manufacturing cells, is proposed. Based on simulation results, the joint optimal MBRP/HPP parameters are obtained through a numerical approach that combines design of experiment, analysis of variance and response surface methodologies. The joint optimal MBRP/HPP policy is compared to classical joint ARP/HPP and BRP/HPP optimal policies, and the results show that the proposed MBRP/HPP outperforms the latter. Sensitivity analyses are also carried out in order to confirm the superiority of the proposed MBRP/HPP, and it is observed that for practitioners, the proposed joint MBRP/HPP offers not only cost savings, but is also easy to manage, as compared to the ARP/HPP policy.     

The resource constrained multi-item inventory problem with price discount: a geometric programming approach

In this paper we present a geometric programming approach for determining the inventory policy for multiple items having price discount and a limit on the total average inventory of all the items. An example is solved to illustrate the method.     

Revised MRP for reducing inventory level and smoothing order releases: a case in manufacturing industry

Although material requirement planning (MRP) systems are widely used in manufacturing companies, they exhibit significant drawbacks. Rev MRP algorithm has been developed in order to reduce the system nervousness, generate a more regular pattern of order released and lower inventory levels. The aim of this paper is to test the Rev MRP algorithm on the case of one of the largest Italian manufacturing companies of home appliances. The company provided three sets of real data, referring to three different runs of their MRP. Results showed that the Rev MRP outperformed the company’s MRP smoothing the production order releases, eliminating overshoots and drastically reducing the inventory levels along the supply chain, even in case of frequent forecasts updates.     

面临汇率和供应风险的双渠道采购决策研究

多渠道采购是制造商降低采购风险的有效手段之一。本文考虑一个制造商向两个供应商进行联合采购的最优决策问题。其中本土(国内)供应商价格稳定,但供应不可靠;母国(国外)供应商供应可靠,但实际价格受汇率波动影响。本文研究了制造商在风险厌恶情形下的最优联合采购决策,并与风险中性情形进行了比较。研究表明,风险中性制造商只会向一个供应商采购;而风险厌恶制造商的采购决策会受到供应可靠性、汇率的波动以及两者相关关系的影响。具体来说,当产品合格率和汇率相对独立时,风险厌恶的制造商倾向于单渠道采购;当合格率和汇率相关时则可能选择双渠道采购以分散风险。数值实验表明,双渠道采购可以有效降低制造商的损失风险。     

行为库存管理研究综述及前景展望

库存管理是运作管理学科的研究重点之一.由于其在经济活动中具有重要的地位,库存管理在行为运作管理这一新兴学科中再次成为学术界关注的焦点.本文首先简述了行为运作管理的行为理论基础以及行为经济学的发展,根据行为运作管理的研究目标构建了行为库存管理的整体研究框架,进而在这一框架下对现有的行为库存管理相关研究进行系统综述,并进一...     

Linking inventory efficiency,productivity and responsiveness to retail firm outperformance: empirical insights from US retailing segments

This paper establishes an empirical model linking a retail firm’s inventory management effectiveness to superior competitive operational performance for specific product-line retail segments. Using 16?years of US retail firm financial data from the COMPUSTAT Fundamentals database across 12 distinct competitive retailing segments, we develop and test a time-series model that links several inventory management execution measures to the competitive operational outperformance of retail firms. The analysis presented provides strong evidence that measures of inventory management performance are not ‘one size fits all’ for the retail industry, and helps to explain why extant research has had difficulty linking inventory control policy effectiveness to operational performance advantages in retailing. We discuss the implications of these empirical findings on the study of inventory policy execution, and offer some guidance for further research.     

Optimal pricing and production decisions in the presence of symmetrical and asymmetrical substitution

Firms may produce a variety of generally similar products or may practice “scientific pricing” or revenue management where the firm will offer similar or somewhat differentiated products in multiple market segments at different prices. Whenever generally similar products are available, the demand for the products is linked through the ability of the customer to substitute one product for another. One widely known type of demand substitution is referred to as inventory-driven substitution where a customer will substitute for a product that is out of stock by buying a similar product. A second type of substitution occurs as a response to price-differences when a customer substitutes a less expensive product for a similar higher priced product.     

On the integration of production,inventory and trade-credit policies

The primary objective of this paper is to highlight the need for the integration of procurement, production and marketing strategies. This is accomplished through the development of a model for a small firm, where the objective is the maximization of the present value of profits within an infinite horizon framework Other features include a JIT-like procurement system, a continuous production situation and a combination of cash discounts and credit period to stimulate sales. A numerical example is presented to illustrate the main features of the study.