第九章库存决策

9-1库存决策CR(2004)PrenticeHall,Inc.Chapter9每一个管理上的失误最后都会变成库存。“Everymanagementmistakeendsupininventory.”MichaelC.BergeracFormerChiefExecutiveRevlon,Inc.9-2产品计划三角形ProductinthePlanningTriangleCR(2004)PrenticeHall,Inc.PLANNINGORGANIZINGCONTROLLINGTransportStrategy•Transportfundamentals•TransportdecisionsCustomerservicegoals•Theproduct•Logisticsservice•Ord.proc.&info.sys.InventoryStrategy•Forecasting•Inventorydecisions•Purchasingandsupplyschedulingdecisions•Storagefundamentals•StoragedecisionsLocationStrategy•Locationdecisions•Thenetworkplanningprocess计划组织控制TransportStrategy•Transportfundamentals•TransportdecisionsCustomerservicegoals•Theproduct•Logisticsservice•Ord.proc.&info.sys.InventoryStrategy•Forecasting•Inventorydecisions•Purchasingandsupplyschedulingdecisions•Storagefundamentals•StoragedecisionsLocationStrategy•Locationdecisions•Thenetworkplanningprocess库存战略预测客户服务目标采购和供应时间决策存储基础知识存储决策产品物流服务订单管理和信息系统库存决策运输战略运输基础知识运输决策选址战略选址决策网络规划流程9-3InventoryDecisionsinStrategyCR(2004)PrenticeHall,Inc.PLANNINGORGANIZINGCONTROLLINGTransportStrategy•Transportfundamentals•TransportdecisionsCustomerservicegoals•Theproduct•Logisticsservice•Ord.proc.&info.sys.InventoryStrategy•Forecasting•Inventorydecisions•Purchasingandsupplyschedulingdecisions•Storagefundamentals•StoragedecisionsLocationStrategy•Locationdecisions•ThenetworkplanningprocessPLANNINGORGANIZINGCONTROLLINGTransportStrategy•Transportfundamentals•TransportdecisionsCustomerservicegoals•Theproduct•Logisticsservice•Ord.proc.&info.sys.InventoryStrategy•Forecasting•Inventorydecisions•Purchasingandsupplyschedulingdecisions•Storagefundamentals•StoragedecisionsLocationStrategy•Locationdecisions•Thenetworkplanningprocess9-4CR(2004)PrenticeHall,Inc.什么是库存WhatareInventories?•库存就是在企业生产和物流渠道中各点堆积的原材料、供给品、零部件、半成品和成品。CR(2004)PrenticeHall,Inc.WhereareInventories?MaterialsourcesInboundtransportationProductionOutboundtransportationFinishedgoodswarehousingCustomersInventorylocationsFinishedgoodsShippingInventoriesin-processReceivingProductionmaterials9-4原料来源生产内向运输外向运输成品储存客户原材料半成品成品库存选址9-6CR(2004)PrenticeHall,Inc.9.1对库存的评述9.1.1库存原因ReasonsforInventories1.改善客户服务2.降低成本首先，保有库存可以使生产的批量更大、批次更少，运作水平更高，因而产生经济效益其次，保有库存有助于实现采购和运输中的成本节约第三，先期购买可以在当前交易的低价位购买额外数量的产品。第四，抵销生产和运输过程中的不确定性第五，应付突发事件。9-7CR(2004)PrenticeHall,Inc.9.1对库存的评述9.1.1库存原因ReasonsforInventories•Improvecustomerservice-Providesimmediacyinproductavailability•Encourageproduction,purchase,andtransportationeconomies-Allowsforlongproductionruns-Takesadvantageofprice-quantitydiscounts-Allowsfortransporteconomiesfromlargershipmentsizes•Actasahedgeagainstpricechanges-Allowspurchasingtotakeplaceundermostfavorablepriceterms•Protectagainstuncertaintiesindemandandleadtimes-Providesameasureofsafetytokeepoperationsrunningwhendemandlevelsandleadtimescannotbeknownforsure•Actasahedgeagainstcontingencies-Buffersagainstsucheventsasstrikes,fires,anddisruptionsinsupply9-8CR(2004)PrenticeHall,Inc.9.1.2反对保有库存的原因ReasonsAgainstInventories•第一，库存被认为是一种浪费•第二，库存可能掩盖质量问题•第三，保有库存鼓励人们以独立的观点来看待物流渠道整体的管理问题9-9CR(2004)PrenticeHall,Inc.9.1.2反对保有库存的原因ReasonsAgainstInventories•Theyconsumecapitalresourcesthatmightbeputtobetteruseelsewhereinthefirm•Theytoooftenmaskqualityproblemsthatwouldmoreimmediatelybesolvedwithouttheirpresence•Theydivertmanagement’sattentionawayfromcarefulplanningandcontrolofthesupplyanddistributionchannelsbypromotinganinsularattitudeaboutchannelmanagement9-10•流通渠道Pipeline（Inventoriesintransit）•投机Speculative-Goodspurchasedinanticipationofpriceincreases•定期性或周期性特征Regular/Cyclical/Seasonal-Inventoriesheldtomeetnormaloperatingneeds•安全Safety-Extrastocksheldinanticipationofdemandandleadtimeuncertainties•仓耗Obsolete/DeadStock-Inventoriesthatareoflittleornovalueduetobeingoutofdate,spoiled,damaged,etc.9.2库存类型TypesofInventories9-11•持久性需求Perpetualdemand-Continueswellintotheforeseeablefuture•季节性需求Seasonaldemand-Varieswithregularpeaksandvalleysthroughouttheyear•尖峰需求Lumpydemand-Highlyvariable•规律性需求Regulardemand-Nothighlyvariable(3Mean)•终端需求TerminatingdemandDemandgoesto0inforeseeablefuture•派生需求DeriveddemandDemandisdeterminedfromthedemandofanotheritemofwhichitisapart9.3库存管理类型的分类9.3.1需求特点NatureofDemandAccuratelyforecastingdemandissinglythemostimportantfactoringoodinventorymanagement9-12CR(2004)PrenticeHall,Inc.•拉动式库存管理法Pull-基于每个仓库的特定需求以一定的订货批量补足库存-每一个存储点独立Eachstockinglocationisconsideredindependent-最大化控制库存Maximizeslocalcontrolofinventories•推动式库存管理法Push根据总需求分配产品到库存点鼓励规模生产准时生产制Just-in-time同步库存流量以满足需求Attemptstosynchronizestockflowssoastojustmeetdemandasitoccurs最小化库存Minimizestheneedforinventory9.3.2管理思想InventoryManagementPhilosophies9-13CR(2004)PrenticeHall,Inc.•拉动式库存管理法Pull-Drawsinventoryintothestockinglocation-Eachstockinglocationisconsideredindependent-Maximizeslocalcontrolofinventories•推动式库存管理法PushAllocatesproductiontostockinglocationsbasedonoveralldemandEncourageseconomiesofscaleinproduction•准时生产制Just-in-timeAttemptstosynchronizestockflowssoastojustmeetdemandasitoccursMinimizestheneedforinventory9.3.2管理思想InventoryManagementPhilosophies9-14CR(2004)PrenticeHall,Inc.•供给驱动Suppl