第七章运输决策

7-1运输决策TransportDecisionsCR(2004)PrenticeHall,Inc.第七章Chapter7Ifyouareplanningforoneyear,growrice.Ifyouareplanningfor20years,growtrees.Ifyouareplanningforcenturies,growmen.AChineseproverb7-2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7-3TransportDecisionsinTransportStrategyPLANNINGORGANIZINGCONTROLLINGTransportStrategy•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•ThenetworkplanningprocessCR(2004)PrenticeHall,Inc.7-4Justafewofthemanyproblemsintransportation典型的运输决策TypicalTransportDecisionsCR(2004)PrenticeHall,Inc.模式、服务选择Mode/ServiceselectionPrivatefleetplanning-路线选择Carrierrouting-多起迄点问题Routingfrommultiplepoints-Routingfromcoincidentorigin-destinationpoints起迄点重合问题-车辆线路和时刻表VehicleroutingandschedulingFreightconsolidation7-57.1运输服务的选择7.1.1基本的成本权衡Costtypes运输Transportation在途库存Intransitinventory工厂库存Sourceinventory基层库存Destinationinventory7.1.2考虑竞争因素7.1.3对选择方法的评价7-6方式选择Mode/ServiceSelection(Cont’d)ExampleFinishedgoodsaretobeshippedfromaplantinventorytoawarehouseinventorysomedistanceaway.Theexpectedvolumetobeshippedinayearis1,200,000lb.Theproductisworth$25perlb.andtheplantandcarryingcostsare30%peryear.Otherdataare:CR(2004)PrenticeHall,Inc.TransportchoiceRate,$/lb.Transittime,daysShipmentsize,lb.Rail0.1125100,000Truck0.201340,000Air0.88116,000IncludetransportrateTransportSelectionAnalysisCosttypeCompu-tationRailTruckAirTrans-portationRD.11(1,200,000)=$132,000.20(1,200,000)=$240,000.88(1,200,000)=$1,056,000In-transitinventoryICDT365[.30(25)´1,200,000(25)]/365=$616,438[.30(25)´1,200,000(13)]/365=$320,548[.30(25)´1,200,000(1)]/365=$24,658PlantinventoryICQ2[.30(25)´100,000]/2=$375,000[.30(25)´40,000]/2=$150,000[.30(25)´16,000]/2=$60,000WhseinventoryIC'Q2[.30(25.11)´100,000]/2=$376,650[.30(25.20)´40,000]/2=$151,200[.30(25.88)´16,000]/2=$62,112Totals$1,500,088$861,748$1,706,770ImprovedserviceCR(2004)PrenticeHall,Inc.7-67-87.2路线选择基本类型一是起讫点不同的单一路径规划二是多个起讫点的路径规划三是起点和终点相同的路径规划7-97.2.1起讫点不同的单一路径问题已知一个由链和节点组成的网络，其中节点代表由链连接的点，链代表节点之间的成本（距离、时间或距离和时间的加权平均）。最初，所有的节点都是未知解，只有起点是已解的节点。7-10第n次迭代的目的。找出第n个距起点最近的节点。对ｎ＝１，２，．．．重复此过程，直到所找出的最近节点是终点。第ｎ次迭代的输入值。在前面的迭代过程中找出（n-1)距起点最近的节点，及其距起点最短的路径和距离。这些节点和起点统称为已解的节点，其余的称为未解的节点。7-11第n个最近节点的候选点。每个已解的节点直接和一个或多个未解的节点相连接，就可以得出一个候选点－－连接距离最短的未解点。如果有多个距离相等的最短路径连接，则有多个候选点。计算出第ｎ个最近的节点。将每个已解节点与其候选节点之间的距离累加到该已解节点与起点之间最短路径的距离上。所得出的总距离最短的候选点就是地n个最近的节点，其最短路径就是得出该距离的路径。若多个候选点都得出相等的最短距离，则都是已解的节点。7-12OriginAmarilloOklahomaCityDestinationFortWorthABEICDGFHJ90minutes848413834815648132150126132120661264860Note:Alllinktimesareinminutes90CarrierRouting(Cont’d)CanbeaweightedindexoftimeanddistanceCR(2004)PrenticeHall,Inc.7-13ShortestRouteMethodCR(2004)PrenticeHall,Inc.StepSolvedNodesDirectlyConnectedtoUnsolvedNodesItsClosestConnectedUnsolvedNodeTotalCostInvolvednthNearestNodeItsMinimumCostItsLastConnectiona1AB90B90AB*2AC138C138ACBC90+66=1563AD348BE90+84=174E174BE*CF138+90=2284AD348CF138+90=228F228CFEI174+84=2585AD348CD138+156=294EI174+84=258I258EI*FH228+60=2886AD348CD138+156=294FH228+60=288H288FHIJ258+126=3847AD348CD138+156=294D294CDFG288+132=360HG288+48=336IJ258+126=3848HJ288+126=414IJ258+126=384J384IJ*7-14MAPQUESTSOLUTIONMapquestat(2004)PrenticeHall,Inc.7-15Plant1Requirements=600Plant2Requirements=500Plant3Requirements=300SupplierASupply400SupplierCSupply500SupplierBSupply7004a76555958aThetransportationratein$pertonforanoptimalroutingbetweensupplierAandplant1.7.2.2多起讫点问题RoutingfromMultiplePointsThisproblemissolvedbythetraditionaltransportationmethodoflinearprogrammingCR(2004)PrenticeHall,Inc.7-16TRANLPproblemsetupSolutionCR(2004)PrenticeHall,Inc.7-177.2.3起迄点重合问题配送饮料到酒吧和饭店安排时间线路将现钞送到自动提款机收集饭店的油脂网上杂货店的配送从仓库到零售点的配送邮车的配送线路校车线路7-181.各点空间相连DDDepotDepot(a)Poorrouting--pathscross(b)Goodrouting--nopat