保修产品最优预防维修策略

保修期内进行预防性维修可以降低厂家保修费用,提高产品的可用度,延长产品使用寿命。老化产品的维修通常是不完全维修:产品维修后不能达到修复如新状态,但是故障率降低。假设产品经预防性维修后故障率恢复到某一特定值,以保修费用为目标建立基于改善因子的不完全预防性维修模型,并通过实例确定保修费用最低时的最佳维修间隔期。     

政府采购成本分析

一、政府采购成本的构成(一)采购成本。政府采购过程中所产生的采购成本是采购货物、工程和服务的价格。一般来说,政府采购成本与投标人的投标成本密切相关,它包含产品的生产成本、市场费用、相关税金、交易成本、制造商售后保修维修费用(在政府采购成本中,售后保修维修费用至关重要)、制造商及经销商的利润等等。实行政府集中采购制度,运用公开招投标方式引入价格竞争机制,在降低政府采购成本上取得了很大成效。通过对投标人的投标价格进行成本分析,投标人投标价格中产品的生产成本、市场费用、相关税金在一定时间、一定程度上是稳定的,降…     

基于A-C算法的生鲜库存成本控制

针对生鲜产品零售商的订货策略制定不当导致库存成本较高的问题,充分考虑零售商库存限制因素及成本控制中的各类因素,通过设计强化学习四元组(环境状态观测、智能体行动、状态迁移、报酬),构建了一个A-C算法的生鲜产品库存成本控制模型。实验结果表明,当库存的相关成本,订货提前期一致的情况下,采用基于AC算法模型的订货策略能够有效降低零售商的生鲜库存成本。     

编读沙龙

来函照登要"保修"更要"保质"时下,作为售后服务的保修已受到越来越多的厂家重视。从"保修一年"到"保修三年",从"保修五年"到"终身保修",时间越拉越长。诚然,重视产品的售后服务,这固然是件好事。但老是围着"保修"打转转,不在产品质量上下功夫,这就未免本末倒置了,这样做,即使"保修"喊得再响,时间拉得再长,恐怕这靠"保修"的产品也要使消费者感到头痛的。     

机械产品并行成本估算研究

本文分析了机械产品在设计阶段的成本估算策略,提出了与设计进程并行的、基于特征的成本估算模型,并且重点研究了设计特征、制造特征、装配特征和成本特征之间特征映射的流程和实现方法以及在此基础上产品制造成本估算的实现方法。     

大型医疗设备保修业务经济性分析

大型医疗设备保修业务的经济性直接影响医院的效益和发展。文章从完善大型医疗设备保修的角度出发,深入分析造成大型医疗设备保修成本昂贵的主要原因,并根据原因提出完善的对策。     

机械产品并行成本估算研究

本文分析了机械产品在设计阶段的成本估算策略,提出了与设计进程并行的、基于特征的成本估算模型,并且重点研究了设计特征、制造特征、装配特征和成本特征之间特征映射的流程和实现方法以及在此基础上产品制造成本估算的实现方法.     

我国彩电产品售后保证成本模型及实证分析

虽然我国许多彩电企业把产品售后保证作为重要营销策略在实际工作中应用，但很少从产品售后保证成本角度研究产品售后保证策略对企业生产经营活动的影响。本文根据有关机构推荐彩电产品MTTF威布尔分布函数，在产品售后保证期限为1－5年情况下，采用产品保证成本模型优化处理产品售后保证策略。     

考虑多类型产品新鲜度的生鲜配送路径优化

生鲜产品由于其特殊性,在配送过程中存在损耗。针对不同种类的生鲜产品,差异化新鲜度敏感系数,引入生鲜努力保鲜系数,构建生鲜产品新鲜度函数,同时考虑固定成本、运输成本、制冷成本、货损成本及时间惩罚成本,构建了生鲜配送路径优化模型。设计混合遗传粒子群算法进行求解,验证了模型的合理性及算法的有效性。对比不同的生鲜努力保鲜系数对各项成本的影响,得出综合成本最优的保鲜策略,为生鲜企业末端配送优化提供参考。     

基于环状城市模型的“嘀嘀”软件盈利模式探讨

本文主要讨论了“嘀嘀”软件的盈利策略.首先,构建环状城市模型,求出产品差异条件下成本最小化时出租车市场上移动打车软件的最优数量.其次,基于寡头市场静态模式视角,建立“出租车与移动打车软件”双寡头市场模型.最后,得出“嘀嘀”在产品差异化-成本最小化基础上应该实施价格-跟随策略.     

应急物流服务网点选址模型研究

应急物流是应对突发事件的重要保障。应急物流可以降低灾害影响程度,缩短受害持续时间,使突发性事件造成损失最小化。而在进行应急物流决策时,首先会面临应急物流服务网点的选址问题。应急物流服务网点置于合理的位置,不仅可以降低成本,而且还能够保证提供应急物资的时效性,从而避免可能导致的更大损失。在给定限制条件下应急服务网点选址模型基础上,综合考虑应急需求的随机性和由灾害导致应急配送时间模糊的不确定情况,研究新的模糊和随机混合机会约束规划选址模型。     

基于商品性质的多级分销模式选择及网络库存定位模型的研究

本文以典型的多级分销网络为研究对象,从商品的需求量、需求波动及商品价值等特性对分销网络的服务能力和成本水平的影响出发,对如何根据不同商品特性选择科学的分销模式及如何在多级网络中进行合理的库存定位问题进行了研究,并基于此提出了一个可行的定性分析模型,借助此模型,可帮助企业在设计分销网络和现有网络的优化过程中,根据所经营商品的不同特性进行合理的网络设计和运营,大大提高网络运营效率。     

第三方军事物流运作模式与架构分析

第三方军事物流是指各类军事物资业务主管部门（供方）和部队用户（需方）将其物流保障工作交由专业的军事物流服务机构来运作．以便提高后勤和装备综合保障效益的一种新型军事物流模式，在军事领域中具有重要作用。文章分析了第三方军事物流的由来，提出它的运作模式，构造了它的框架，最后探讨了它的实施策略．     

服务保证设计要素研究

服务保证是产品保证在服务领域内的扩展与延伸。自上世纪80年代以来,学者们对服务保证的概念、设计要素、基本类型等进行了深入研究。本文回顾了国内外学者对服务保证概念的界定,并对服务保证类型和服务保证设计要素进行了系统的梳理,结果发现:服务保证的概念基本趋于一致;服务保证的基本类型及保证范围获得了学者们的基本认可,但对不同类型服务保证设计要素研究不足,对补偿措施及调用过程也缺乏深入分析。本文对未来的研究趋势进行了展望。     

The effect of lot-sizing on workload variability

Lot-sizing models which group demand requirements for one or more consecutive time periods into a single production run have received considerable attention in recent years. Material Requirements Planning (MRP) systems must, for instance, make a lot-size decision for each planned order release. Existing decision models attempt to minimize the sum of setup plus inventory holding costs. However, lot-sizing tends to increase the work center load variability, and, consequently, the costs associated with changing production levels from period to period should be incorporated into the economic analysis. This study is concerned, first of all, with analytically describing the relationship between dynamic lot-sizing models and workload variability. Secondly, in order to account for production level change costs we propose a simple modification to existing heuristic models. Lastly, we employ a simulation model to empirically extend these results to a typical MRP multiechelon production environment. An example is included to show clearly that with cost premiums for overtime and severance or guaranteed minimum costs for undertime the traditional lot-sizing techniques significantly underestimate actual costs and can lead to very costly policies.Mean, variance and coefficient of variation of period work time requirements are derived as a function of several algorithm characteristics. Average cycle time (number of periods covered by a single batch) is found to be the most influential factor in determining workload variability. Variance grows approximately in proportion to this cycle time with the proportionality constant being the square of average period workload. Cycle time and demand variability also contribute to workload variability. Results indicate that for a given average cycle time, the EOQ method will minimize workload variability. When N products utilize the same work center, the coefficient of load variation will be reduced by a factor of N^{?$\text{1}\text{2}$} unless requirements are positively correlated. Positive correlation would result when products have similar seasons or parent items. In this case grouping such products cannot help reduce variability.In order to incorporate production level change costs into existing heuristics we may simply introduce a term consisting of a penalty factor times average cycle time. The penalty factor represents the costs of period by period production level changes. Several popular heuristics are extended in this fashion, and it is found that solutions are still readily obtainable, requiring only modifications to setup or holding cost parameters.The effects of level change costs are examined via simulation for a specific yet typical environment. It is found that when setup costs are significant, traditional lot-sizing heuristics can provide cost savings and service level improvements as compared to lot-for-lot production. However, whereas for our model the obtainable profit improvement from lot-sizing was 25% in the case of freely variable capacity, actual improvements were only one half as large when reasonable hiring and firing practices and overtime and undertime costs were considered. Consequently, management needs to consider carefully labor costs and work center product relationships when determining a production scheduling method.     

Strategic segmentation in front-line services: matching customers,employees and human resource systems

This paper examines variation in the use of high involvement work practices in service and sales operations. I argue that the relationship between the customer and front-line service provider is a central feature that distinguishes production-level service activities from manufacturing. In particular, through strategic segmentation, firms are able to segment customers by their demand characteristics and to match the complexity and potential revenue stream of the customer to the skills of employees and the human resource system that shapes the customer–employee interface. Unlike manufacturing, where high involvement systems have emerged in a wide variety of product markets, therefore, service organizations are likely to use high involvement systems only to serve higher value-added customers because of the high costs of these systems and the labour-intensive nature of services. Data from a nationally random sample of 354 call centres in US telecommunications documents this pattern: from classic mass production approaches for back office workers and increasingly for front office residential service agents, to greater involvement for small business service providers and high involvement practices for middle-market service agents.     

Focused Firms and the Incentive to Innovate

This paper explores the possibility that a firm may make a credible strategic commitment to high levels of innovation by limiting its horizontal or vertical scope. Specifically, I develop a model in which a firm decides whether to undertake an innovation that affects a system of products, which can also be interpreted as multiple stages of the production process. The products are technologically related, and innovation in the core product is assumed to impose costs on the producers of ancillary products, due to cannibalization of the old technology and redesign or retooling costs, for example. I demonstrate that a firm may optimally and credibly commit to innovate by choosing to be a focused firm and licensing the production of the ancillary product, even when licensees are inefficient. In stark contrast to the irrelevance results of the strategic delegation literature, this commitment may be credible even when licensing contracts are renegotiable, but only if licensees are sufficiently inefficient.     

Labor's liquidity service and firing costs

This paper studies the specific effect that firing costs can have on firms facing liquidity constraints. When firing costs are zero and a time gap exists between production and its associated revenues, firing allows firms to hold on to their liquid assets by saving on wages, and thus, allows firms to cope better with liquidity shocks when external financing is too costly or unavailable. I refer to this feature as labor's liquidity service. Higher firing costs reduces the value of labor's liquidity service, and thus, increases firms' incentive for hoarding liquidity and reduces firms' demand for production inputs. In addition to this negative effect at the creation margin of production, firing costs have a relatively higher positive effect on the destruction margin of production of financially restricted firms. This paper presents a model that develops these ideas and shows that the presence of firing costs has a stronger negative effect on the output of firms facing liquidity constraints. Regression analysis, based on country-industry panel data sets, provides empirical evidence consistent with the liquidity service effect of firing costs. I find a relatively stronger negative effect of firing costs on the output of industries with higher liquidity requirements and a relatively stronger negative effect of firing costs on the output of small, and more likely financially constrained, firms.     

基于Hotelling模型的服务型制造增值机理研究

为探讨服务型制造对厂商差异化战略的影响,结合服务的特性,构建了区间Hotelling差异化模型:无差异化的产品竞争模型和服务差异化模型.通过对模型进行求解得到最佳服务差异化程度和均衡价格.比较和分析模型结果表明:(1)服务差异化程度大于某个临界值时才会获得正的利润;(2)适度服务差异化可以提升厂商利润和消费者剩余.(3)消费需求模式的变化是服务型制造的关键因素,而厂商移动的边际成本对其采取差异化竞争战略有重要影响.     

Derivation of regional shadow prices

[Hurter and Moses, 1964] presented a solvable model combining input-output analysis and linear programming to derive regional product ’shadow’ prices. Their measure of prices is incomplete since it includes only regional variation-in transport and resource costs and not the intermediate product costs. The reason for this exclusion is obvious: product prices are needed to obtain intermediate product costs. In this note we extend the Hurter-Moses model to derive a full measure of regional shadow prices.