第十四章 供應鏈中的運輸

14TransportationinaSupplyChainLearningObjectivesUnderstandtheroleoftransportationinasupplychainEvaluatethestrengthsandweaknessesofdifferentmodesoftransportationDiscusstheroleofinfrastructureandpoliciesintransportationIdentifytherelativestrengthsandweaknessesofvarioustransportationnetworkdesignoptionsIdentifytrade-offsthatshippersneedtoconsiderwhendesigningatransportationnetworkTheRoleofTransportation

inaSupplyChainMovementofproductfromonelocationtoanotherProductsrarelyproducedandconsumedinthesamelocationSignificantcostcomponentShipperrequiresthemovementoftheproductCarriermovesortransportstheproductModesofTransportationandtheirPerformanceCharacteristicsAirPackagecarriersTruckRailWaterPipelineIntermodalModesofTransportationandtheirPerformanceCharacteristicsModeFreightValue($billions)in2002FreightTons(billions)in2002FreightTon-Miles(millions)in2002ValueAddedtoGNP(billion$)in2009Air(includestruckandair) 563 6 13 61.9Truck 9,075 11,712 1,515 113.1Rail 392 1,979 1,372 30.8Water 673 1,668 485 14.3Pipeline 896 3,529 688 12.0Multimodal 1,121 229 233Table14-1AirCostcomponentsFixedinfrastructureandequipmentLaborandfuelVariable–passenger/cargoKeyissuesLocation/numberofhubsFleetassignmentMaintenanceschedulesCrewschedulingPricesandavailabilityPackageCarriersSmallpackagesuptoabout150poundsExpensiveRapidandreliabledeliverySmallandtime-sensitiveshipmentsProvideothervalue-addedservicesConsolidationofshipmentsakeyfactorTruckSignificantfractionofthegoodsmovedTruckload(TL)LowfixedcostImbalancebetweenflowsLessthantruckload(LTL)SmalllotsHubandspokesystemMaytakelongerthanTLRailMovecommoditiesoverlargedistancesHighfixedcostsinequipmentandfacilitiesScheduledtomaximizeutilizationTransportationtimecanbelongTrains‘built’notscheduledWaterLimitedtocertaingeographicareasOcean,inlandwaterwaysystem,coastalwatersVerylargeloadsatverylowcostSlowestDominantinglobaltradeContainersPipelineHighfixedcostPrimarilyforcrudepetroleum,refinedpetroleumproducts,naturalgasBestforlargeandstableflowsPricingstructureencouragesuseforpredicablecomponentofdemandIntermodalUseofmorethanonemodeoftransportationtomoveashipmentGrownconsiderablywithincreaseduseofcontainersMaybetheonlyoptionforglobaltradeMoreconvenientforshippers–oneentityKeyissue–exchangeofinformationtofacilitatetransferbetweendifferentmodesTransportationInfrastructure

andPoliciesGovernmentsgenerallytakefullresponsibilityorplayedasignificantroleinbuildingandmanaginginfrastructureelementsWithoutamonopoly,deregulationandmarketforceshelpcreateaneffectiveindustrystructurePricingshouldreflectthemarginalimpactonthecosttosocietyTransportationInfrastructure

andPoliciesFigure14-1DesignOptionsfora

TransportationNetworkWhendesigningatransportationnetworkShouldtransportationbedirectorthroughanintermediatesite?Shouldtheintermediatesitestockproductoronlyserveasacross-dockinglocation?Shouldeachdeliveryroutesupplyasingledestinationormultipledestinations(milkrun)?DirectShipmentNetwork

toSingleDestinationFigure14-2DirectShippingwithMilkRunsFigure14-3AllShipmentsviaIntermediateDistributionCenterwithStorageFigure14-4AllShipmentsviaIntermediateTransitPointwithCross-DockingSupplierssendtheirshipmentstoanintermediatetransitpointTheyarecross-dockedandsenttobuyerlocationswithoutstoringthemShippingviaDCUsingMilkRunsFigure14-5TailoredNetworkNetworkStructureProsConsDirectshippingNointermediatewarehouseSimpletocoordinateHighinventories(duetolargelotsize)SignificantreceivingexpenseDirectshippingwithmilkrunsLowertransportationcostsforsmalllotsLowerinventoriesIncreasedcoordinationcomplexityAllshipmentsviacentralDCwithinventorystorageLowerinboundtransportationcostthroughconsolidationIncreasedinventorycostIncreasedhandlingatDCAllshipmentsviacentralDCwithcross-dockLowinventoryrequirementLowertransportationcostthroughconsolidationIncreasedcoordinationcomplexityShippingviaDCusingmilkrunsLoweroutboundtransportationcostforsmalllotsFurtherincreaseincoordinationcomplexityTailorednetworkTransportationchoicebestmatchesneedsofindividualproductandstoreHighestcoordinationcomplexityTable14-2SelectingaTransportationNetworkEightstores,foursupplysourcesTruckcapacity=40,000unitsCost$1,000perload,$100perdeliveryHoldingcost=$0.20/yearSelectingaTransportationNetworkAnnualsales=960,000/storeDirectshippingBatchsizeshippedfromeach

suppliertoeachstore =40,000unitsNumberofshipments/yrfrom

eachsuppliertoeachstore =960,000/40,000=24Annualtruckingcost

fordirectnetwork =24x1,100x4x8=$844,800Averageinventoryateach

storeforeachproduct =40,000/2=20,000unitsAnnualinventorycost

fordirectnetwork =20,000x0.2x4x8=$128,000Totalannualcostof

directnetwork =$844,800+$128,000=$972,800SelectingaTransportationNetworkAnnualsales=960,000/storeMilkrunsBatchsizeshippedfromeach

suppliertoeachstore =40,000/2=20,000unitsNumberofshipments/yrfrom

eachsuppliertoeachstore =960,000/20,000=48Transportationcostpershipment

perstore(twostores/truck) =1,000/2+100=$600Annualtruckingcost

fordirectnetwork =48x600x4x8=$921,600Averageinventoryateach

storeforeachproduct =20,000/2=10,000unitsAnnualinventorycost

fordirectnetwork =10,000x0.2x4x8=$64,000Totalannualcostof

directnetwork =$921,600+$64,000=$985,600SelectingaTransportationNetworkAnnualsales=120,000/storeDirectshippingBatchsizeshippedfromeach

suppliertoeachstore =40,000unitsNumberofshipments/yrfrom

eachsuppliertoeachstore =120,000/40,000=3Annualtruckingcost

fordirectnetwork =3x1,100x4x8=$105,600Averageinventoryateach

storeforeachproduct =40,000/2=20,000unitsAnnualinventorycost

fordirectnetwork =20,000x0.2x4x8=$128,000Totalannualcostof

directnetwork =$105,600+$128,000=$233,600SelectingaTransportationNetworkAnnualsales=120,000/storeMilkrunsBatchsizeshippedfromeach

suppliertoeachstore =40,000/4=10,000unitsNumberofshipments/yrfrom

eachsuppliertoeachstore =120,000/10,000=12Transportationcostpershipment

perstore(twostores/truck) =1,000/4+100=$350Annualtruckingcost

fordirectnetwork =12x350x4x8=$134,400Averageinventoryateach

storeforeachproduct =10,000/2=5,000unitsAnnualinventorycost

fordirectnetwork =5,000x0.2x4x8=$32,000Totalannualcostof

directnetwork =$134,400+$32,000=$166,400Trade-offsinTransportationDesignTransportationandinventorycosttrade-offChoiceoftransportationmodeInventoryaggregationTransportationcostandresponsivenesstrade-offTrade-offsinTransportationDesignModeCycleInventorySafetyInventoryIn-TransitCostTransportationTimeTransportationCostRail55525TL44433LTL33344Package11161Air22252Water66616Table14-3Trade-offsWhenSelectingTransportationModeDemand=120,000motors,Cost=$120/motor,Weight=10lbs/motor,Lotsize=3,000,Safetystock=50%ddltCarrierRangeofQuantityShipped(cwt)ShippingCost($/cwt)AMRailroad 200+6.50NortheastTrucking 100+7.50GoldenFreightways 50–1508.00GoldenFreightways 150–2506.00GoldenFreightways 250+4.00Table14-4Trade-offsWhenSelectingTransportationMode Cycleinventory =Q/2=2,000/2=1,000motors Safetyinventory =L/2daysofdemand

=(6/2)(120,000/365)=986motors In-transitinventory =120,000(5/365)=1,644motors Totalaverageinventory =1,000+986+1,644

=3,630motors Annualholdingcost

usingAMRail =3,630x$30=$108,900 Annualtransportation

costusingAMRail =120,000x0.65=$78,000 Thetotalannualcostfor

inventoryandtransportation

usingAMRail =$186,900Trade-offsWhenSelectingTransportationModeAlternativeLotSize(Motors)Transpor-tationCostCycleInventorySafetyInventoryIn-TransitInventoryInventoryCostTotalCostAMRail 2,000$78,000 1,000986 1,644$108,900$186,900Northeast 1,000$90,000 500658 986$64,320$154,320Golden 500$96,000 250658 986$56,820$152,820Golden 1,500$96,000 750658 986$71,820$167,820Golden 2,500$86,400 1,250658 986$86,820$173,220Golden 3,000$80,000 1,500658 986$94,320$174,320Golden(oldproposal) 4,000$72,000 2,000658 986$109,320$181,320Golden(newproposal) 4,000$67,000 2,000658 986$109,320$176,820Table14-5TradeoffsWhen

AggregatingInventoryHighval–weeklydemandμH=2,σH=5,weight=0.1lbs,cost=$200Lowval–weeklydemandμL=20,σL=5,weight=0.04lbs,cost=$30CSL

=0.997,holdingcost=25%,L=1week,T=4weeksUPSleadtime=1week,$0.66+0.26xFedExleadtime=overnight,$5.53+0.53xOptionA.KeepthecurrentstructurebutreplenishinventoryonceaweekratherthanonceeveryfourweeksOptionB.Eliminateinventoriesintheterritories,aggregateallinventoriesinafinished-goodswarehouseatMadison,andreplenishthewarehouseonceaweekTradeoffsWhen

AggregatingInventoryHighMedinventorycosts(currentscenario,HighVal)All24territories,HighValinventory=24x34.7=832.8unitsTradeoffsWhen

AggregatingInventoryHighMedinventorycosts(currentscenario,LowVal)All24territories,LowValinventory=24x70.7=1696.8unitsTradeoffsWhen

AggregatingInventory Annualinventory holdingcost forHighMed = (averageHighValinventoryx$200 +averageLowValinventoryx$30)x0.25 = (832.8x$200+169.8x$30)x0.25 = $54,366($54,395withoutrounding)TradeoffsWhen

AggregatingInventoryHighMedtransportationcost(currentscenario)Averageweightofeachreplenishmentorder =0.1QH+0.04QL=0.1x8+0.04x80=4poundsShippingcostperreplenishmentorder =$0.66+0.26x4=$1.70Annualtransportationcost=$1.70x13x24=$530HighMedtotalcost(currentscenario)AnnualinventoryandtransportationcostatHighMed =inventorycost+transportationcost =$54,366+$530=$54,896TradeoffsWhen

AggregatingInventoryCurrentScenarioOptionAOptionBNumberofstockinglocations24241.2unitsReorderinterval4weeks1week1weekHighValcycleinventory96units