周期可变下考虑多车型的库存路径优化研究

目的 研究基于供应商管理库存模式下，由一个供应商和多个零售商组成的二级供应链配送系统的库存路径优化问题，确定计划期内各配送周期的长度、数量，对供应链中库存策略与配送方案问题进行协调优化，使系统总成本最低。方法 考虑的成本包括库存持有成本、缺货成本和配送成本。为降低供应链系统的总成本，提出全新的周期可变策略。结果 采用遗传算法求解得出最佳方案。将不同策略的算例结果进行对比分析，结果表明周期可变策略与周期固定策略相比，系统总成本最低节约比例为1.7%，最高节约比例为42.3%。结论 通过对计划期内各配送周期的长度及数量进行划分调整可以有效地节约系统总成本，同时，采用多车型的配送方案明显优于采用同车型的配送方案。     

电子商务环境下两级供应链库存管理决策研究

本文利用order up to level策略建立需求不确定时两级供应链供应商的库存策略模型并进行参数求解,给出最优库存水平以及管理绩效考核指标的求解方法。并通过实例计算,给出电子商务环境下基于两级供应链的供应商库存最优解决方案,提出随着零售商需求波动程度、库存水准的变动,对于供应商最优库存水平、库存成本、缺货成本的相应策略。     

基于VMI的供需双方利益分配模型

针对解决实施供应商管理库存策略短期内合作双方的责任与利益不统一的问题,在分析库存成本模型,证明该策略能够降低供应链库存成本的基础上,根据双方优势地位的不同,建立了短期内供需双方利益分配模型,并进行了实证研究.该模型对于建立供应商零售商双方稳定的合作关系具有重要的理论与现实意义.     

基于制造延迟的VMI模型的仿真研究

在供应链延迟策略和供应商管理库存(VMI)策略研究的基础上,首先建立了供应链延迟策略下的仿真模型,然后再引入供应商管理库存策略,通过计算机仿真,探讨了供应商管理库存策略实施前后供应链绩效的变化情况.研究结果表明,与单纯的延迟策略相比,延迟与供应商库存相结合的策略能明显改善供应链的绩效.     

基于协同补货期库存协调模型的扩展研究

在协同预测的库存补充策略和基于协同补给期的一个供应商与一个订货商之间的库存协调策略的研究基础之上,主要研究一个供应商与多个订货商库存协调策略,并与协调之前的库存成本相比,用数值实验的方法证明了合作能够降低供应商与订货商的库存成本,增加效益,给供应链带来了整体效益.     

随机需求条件下供应链的补货及折扣策略研究

研究一个供应商和多个零售商围绕单品种商品组成的供应链体系中,以供应商为核心的供应链库存管理,目标是通过直接降低供应商的库存成本,从而降低供应链的总成本.假设每个零售商面对服从随机正态分布的提前期客户需求,在不考虑交货时间的情况下,供应商在固定的时间间隔满足零售商的补货需要,并以价格折扣的方式补偿零售商的成本增加.由此得到较优的补货间隔,并给出了求解方法.最后,通过仿真验证了该解法的可行性并评估了该策略对各方的影响.     

土建项目供应商管理的问题与对策分析

运用采购管理、供应链管理、供应商评价理论,通过对项目采购管理现状的深入调查,从提高企业核心竞争力,降低项目采购成本的目的出发,分析指出了存在于项目供应商管理中的问题,得出了在供应商选择和关系管理方面、项目采购管理规章制度方面等项目采购管理方面存在不足。应用先进理论与本单位实际情况结合得出了完善规章制度及队供应链理论为基础的供应商关系管理实施。     

供应链虚拟库存决策的仿真

在供应链延迟策略和供应商管理库存（VMI）策略研究的基础上,建立了供应链延迟策略下的仿真模型,再引入虚拟库存,通过计算机仿真,探讨了虚拟库存实施前后供应链绩效的变化情况。研究结果表明,与一般的供应商管理库存相比,虚拟库存的引入使得供应链总成本和企业的服务水平均有所增加。     

基于作业成本法的医疗物资TCO优化模型

针对传统医疗物资采购主要关注采购价格、忽视医疗物资供应链成本这一问题,提出了一种结合作业成本法(ABC)与总体拥有成本(TCO)理论的医疗物资TCO优化模型。首先,运用ABC详细分析并核算医疗物资供应链成本,如供应商维持成本、质量检验成本、运输成本及手术延期成本等;然后,通过建立医疗物资TCO优化模型优化医疗物资采购策略。最后,通过分析天津市某三级甲等医院医疗物资采购案例,证明本模型可以有效地降低医疗物资采购成本,并为医院成本控制管理提供合理建议。     

基于VMI的医院供应管理

医院大部分药品及相关用品属于易逝品,针对该类产品的特点,将VMI(Vender Managed Inventory)方法引入到医院供应管理研究中,通过建立两级供应链库存定量模型(即供应商-医院关系模型),比较实施VMI方法前后,医院、供应商以及供应链总库存成本的变化情况.通过定量比较证实,实施VMI方法可以有效降低医院及供应链总库存成本,供应商的库存成本虽有所升高,但是可以通过转移支付方法,使供应商与医院达到利益均衡点,从而降低供应链总库存成本,获得pareto均衡.     

Just-in-time purchasing: an integrated inventory model involving deterministic variable lead time and quality improvement investment

Nowadays supply chain management is a popular practice in manufacturing systems, and just-in-time (JIT) production plays a crucial role in supply chain environments. Companies are using JIT production to gain and maintain a competitive advantage. The characteristics of JIT systems are consistent high quality, small lot sizes, frequent delivery, short lead time, and close supplier ties. This paper presents an integrated inventory model to minimize the sum of the ordering/setup cost, holding cost, quality improvement investment and crashing cost by simultaneously optimizing the order quantity, lead time, process quality and number of deliveries while the probability distribution of the lead time demand is normal. This integrated inventory model is useful particularly for JIT inventory systems where the vendor and the purchaser form a strategic alliance for profit sharing.     

可控提前期供应链库存优化的信用期机制研究

在一个固定订货间隔期模型中,假设提前期可以通过额外的赶工成本进行压缩和卖方提供一定的信用期期限给买方的情况下,建立了可控提前期供应链库存优化的信用期机制模型.首先考虑买卖双方不合作情况下的Stackelberg主从对策博弈模型,求出买方最佳的订货周期、提前期和卖方的最优信用期期限决策,然后考虑买卖双方合作情况下的最优订货周期、提前期和信用期决策.最后利用数值分析对两类模型的优化效果进行比较,结果表明合作情况下买卖双方的收益均比不合作情况下有所改进.     

考虑批量订货成本的最优JIT订货与生产策略

由于增大单次订单量会降低企业订货灵活性,为此引入批量订货成本来衡量采购商从下达订单到收货期间所面临的与订货批量相关的风险成本。采购商通过综合权衡订货成本、运输成本、库存成本以及批量订货成本,从而得出合理的最优订货批量。基于由采购商和供应商组成的供应链,首先在JIT批量分解模式下,研究考虑批量订货成本后,集中式决策和分散式决策下的最优订货和生产策略。由于分散式决策下一方利益最大化时的最优决策常常是另一方无法接受的,进而分析了上下游企业间的不同议价能力,给出了双方均可接受的订货与生产策略。     

Balanced and synchronized ordering in supply chains

This paper considers a supply chain with one supplier and multiple retailers in which base stock policies are practiced. Specifically, we consider two replenishment strategies: synchronized ordering and balanced ordering. We present compelling results to explain how the supplier may benefit from synchronized ordering under fixed order intervals and examine numerically the cost impact to the retailers under the two strategies. We also compare the results of synchronized ordering with randomized ordering times.     

Analysis of the bullwhip effect in multi-product,multi-stage supply chain systems–a simulation approach

This research aims to develop a simulation approach based on system dynamics modelling (SDM) and adaptive network based fuzzy inference system (ANFIS) for quantifying and reducing the bullwhip effect in a multi-product, multi-stage supply chain. The proposed model is comprised of three groups of variables influencing the bullwhip effect, namely the structure of a supply chain network, supply chain contributions (ordering process in regular situation or when a supplier has a promotion or shortage gaming) and supply chain performances (the number of defects and ordering lead time). As a result, a two layer simulation model is developed with three generic models. The flexibility of this proposed approach is its ability to model various types of ordering policies which are basic inventory policies, material requirement planning (MRP) system and just in time (JIT) approach. The supply chain of a beverage company was selected to validate and demonstrate the flexibility of the proposed model. The findings of the proposed simulation model are consistent with the results obtained from the case study. The error magnitude of the bullwhip effect level varied between 0 and 9% resulting in bullwhip effect reductions of up to 92%. Accordingly, the bullwhip effect levels are significantly decreased by using the proposed simulation model.     

Operations planning in a supply chain system with fixed-interval deliveries of finished goods to multiple customers

Raw material ordering policy and the manufacturing batch size for fixed-interval deliveries of finished goods to multiple customers play a significant role in economically managing the supply chain logistics. This paper develops an ordering policy for raw materials and determines an economic batch size for a product at a manufacturing center which supplies finished products to multiple customers, with a fixed-quantity at a fixed time-interval to each of the customers. In this model, an optimal multi-ordering policy for procurement of raw materials for a single manufacturing system is developed to minimize the total cost incurred due to raw materials and finished goods inventories. The carried over inventory of finished goods from the previous cycle is used as initial finished goods inventory, resulting in shifting the production schedule ahead for the next cycle. A closed-form solution to the problem is obtained for the minimal total cost. The algorithm is demonstrated for multiple customer systems.     

Supply chain design to guarantee quoted lead time and inventory replenishment: model and insights

Do lead time constraints only lead to re-think and re-optimise the inventory positioning along the supply chain or can they impact on the design of the supply chain itself? To answer such a question, we integrate the lead time constraints in a multi-echelon supply chain design model and challenge the difficulty of combining in the same model the long-term decisions (facility location, supplier selection) with the midterm decisions (inventory placement and replenishment, delivery lead time). The model guarantees the respect of the quoted lead time associated with each customer order and the replenishment of the different stocks (raw materials, intermediate and final products) in the different stages of the supply chain between any pair of consecutive orders. We use the model to investigate the impact of the quoted lead time and customer’s order frequency on supply chain design decisions and costs. Some of our results indicate that the lead time constraints can lead to bringing the sites of manufacturing and distribution close to the demand zone and to select local suppliers in spite of their higher cost.     

基于供应链的企业库存成因及优化控制的研究（一）

基于企业全面库存的管理思想,对库存成本、库存控制、库存系统优化等管理经验与前人研究成果进行分析,借鉴先进企业的库存管理理念和方法,以大型制造企业为核心研究对象,在集供应商、制造商、经销商为一体的供应链作为研究框架的基础上,运用供应链系统理论作为研究方法,分析了库存管理现状、影响因素及产生原因,从优化生产管理、整合企业内部供应链和跨企业供应链的角度提出了库存控制的相应对策,以实现全面的库存优化,提高经营效益。     

基于VMI的供应链协调模型应用研究

以一个制造商和一个供应商构成的多产品、多阶段供应链为背景,使用多目标规划的方法构造了生产原料平衡、制造商利润和供应商利润等目标函数及其约束条件,建立了供应商管理制造商生产原料库存的供应链协调模型.为验证模型的有效性和可行性,设计了一个应用算例.算例的分析表明:基于VMI的供应链协调模型能够保证各阶段供应商的交付量等于制造商的订购量,使制造商的利润提高,但供应商因实施VMI利润降低了.最后,通过对产品市场价格、原材料价格、生产能力、市场容量等参数的灵敏度分析,找出了供应链各参量的变化规律.