生產(chǎn)與運(yùn)作管理2剖析

生產(chǎn)與運(yùn)作管理2剖析第二章設(shè)施與作業(yè)設(shè)計(jì)

（DesignofFacilitiesandJobs）設(shè)施位置選擇（FacilityLocation）

設(shè)施布置（FacilityLayout）*作業(yè)設(shè)計(jì)（JobDesign）

第一節(jié)設(shè)施位置選擇（FacilityLocation）設(shè)施位置決策（Decision）設(shè)施位置選擇的因素（Considerations）設(shè)施位置分析方法（Methods）InGeneral-LocationDecisionsLong-termdecisionsDifficulttoreverseAffectfixed&variablecostsTransportationcostAsmuchas25%ofproductpriceOthercosts:Taxes,wages,rentetc.Objective:MaximizebenefitoflocationtofirmIndustrialLocationDecisionsCostfocusRevenuevarieslittle

betweenlocationsLocationisamajor

costfactorAffectsshipping&

productioncosts(e.g.,labor)Costsvarygreatlybetween

locationsServiceLocationDecisionsRevenuefocusCostsvarylittlebetweenmarketareasLocationisamajor

revenuefactorAffectsamountof

customercontactAffectsvolumeof

businessLocationDecisionSequenceCountryRegion/CommunitySiteFactorsAffectingLocation資源（人力、原材料、能源、資本、土地的價(jià)格及其供應(yīng)狀況）運(yùn)輸（費(fèi)用及其設(shè)施狀況）市場(chǎng)（需求量、結(jié)構(gòu)、競(jìng)爭(zhēng)、價(jià)格、顧客分布及其需求特點(diǎn)）建筑（費(fèi)用及其條件）；稅收、保險(xiǎn)（種類、政策及其水平）；自然條件（氣候、地理位置、地質(zhì)狀況）；經(jīng)濟(jì)條件（基礎(chǔ)設(shè)施、生活質(zhì)量）；社會(huì)條件（文化習(xí)俗、公眾態(tài)度）；政治條件（政府政策及其態(tài)度、政治穩(wěn)定）。LocationEvaluationMethodsFactor-ratingmethodLocationalbreak-evenanalysisCenterofgravitymethodTransportationmodelFactor-RatingMethodMostwidelyusedlocationtechniqueUsefulforservice&industriallocationsRateslocationsusingfactorsIntangible(qualitative)factorsExle:Educationquality,laborskillsTangible(quantitative)factorsExle:Short-run&long-runcostsExle：FactorRatingMethodMethodofcost-volumeanalysisusedforindustriallocationsStepsDeterminefixed&variablecostsforeachlocationPlottotalcostforeachlocationSelectlocationwithlowesttotalcostforexpectedproductionvolumeMustbeabovebreak-evenLocationalBreak-EvenAnalysisLocationalBreak-EvenAnalysisExleYou’reananalystforACDelco.You’reconsideringanewmanufacturingplantinAkron,BowlingGreen,orChicago.Fixedcostsperyearare$30k,$60k,&$110krespectively.Variablecostspercaseare$75,$45,&$25respectively.Thepricepercaseis$120.Whatisthebestlocationforanexpectedvolumeof2,000casesperyear?LocationalBreak-EvenCrossoverChart050000100000150000200000050010001500200025003000VolumeAnnualCostAkronChicagoBowlingGreenAkronlowestcostBowlingGreenlowestcostChicagolowestcostCenterofGravityMethodFindslocationofsingledistributioncenterservingseveraldestinationsUsedprimarilyforservicesConsidersLocationofexistingdestinationsExle:Markets,retailersetc.VolumetobeshippedShippingdistance(orcost)Shippingcost/unit/mileisconstantCenterofGravityMethodStepsPlaceexistinglocationsonacoordinategridGridhasarbitraryorigin&scaleMaintainsrelativedistances

Calculatex&ycoordinatesfor‘centerofgravity’GiveslocationofdistributioncenterMinimizestransportationcostMinimizestransportationcostCenterofgravityExlexy(x*,y*)2000100010002000x*=66.7y*=93.3TransportationModelFindsamounttobeshippedfromseveralsourcestoseveraldestinationsUsedprimarilyforindustriallocationsTypeoflinearprogrammingmodelObjective:Minimizetotalproduction

&shippingcostsConstraintsProductioncapacityatsource(factory)DemandrequirementatdestinationExle：TransportationModel在S4的最優(yōu)結(jié)果在S5的最優(yōu)結(jié)果在S6的最優(yōu)結(jié)果最優(yōu)廠址S4——34698S5——34867S6——34818S4：最優(yōu)廠址第二節(jié)設(shè)施布置（FacilityLayout）布置的目標(biāo)(Objectives)布置的類型(Type)布置的方法(Methods)WhatisFacilityLayoutLocationorarrangementofeverythingwithin&aroundbuildingsObjectivesaretomaximizeCustomersatisfactionUtilizationofspace,equipment,&peopleEfficientflowofinformation,material,&peopleEmployeemorale&safetyConstraintsonLayoutObjectivesProductdesign&volumeProcessequipment&capacityQualityofworklifeBuildingandsite重新布置的具體原因(Reasons)（１）低效率的作業(yè)（例如，高費(fèi)用、瓶頸）。（２）安全事故或危險(xiǎn)。（３）新產(chǎn)品或服務(wù)的引進(jìn)。（４）產(chǎn)品或服務(wù)設(shè)計(jì)的變化。（５）新工藝的引進(jìn)，原有工藝的改進(jìn)。（６）產(chǎn)量或產(chǎn)品組合的變化（７）方法或設(shè)備的變化。（８）環(huán)境或其他法規(guī)要求的變化。（9）士氣問題（例如，缺乏面對(duì)面的接觸）。布置的基本類型(BasicTypeofLayouts)Process-orientedlayoutdealswithlow-volume,high-varietyproduction(“jobshop”,intermittentproduction)Product-orientedlayoutseeksthebestpersonnelandmachineuseinrepetitiveorcontinuousproductionFixed-positionlayoutlargebulkyprojectssuchasshipsandbuildings面向過程布置(Process-OrientedLayout)按加工處理的工藝性質(zhì)分別設(shè)置相應(yīng)的生產(chǎn)單位，使產(chǎn)品或顧客依次經(jīng)過相應(yīng)的各生產(chǎn)單位接受所需的特殊的加工處理或服務(wù)。一個(gè)生產(chǎn)單位是一種工藝性質(zhì)的設(shè)備、工人等的集合體，進(jìn)行一種工藝性質(zhì)的加工處理或服務(wù)。它能處理各種具有不同加工要求的但加工性質(zhì)相同的產(chǎn)品或服務(wù)。面向產(chǎn)品布置(Product-OrientedLayout)按產(chǎn)品或顧客的性質(zhì)分別設(shè)置相應(yīng)的生產(chǎn)單位，使某種產(chǎn)品或顧客在一個(gè)生產(chǎn)作業(yè)單位里的得到所需的幾乎全部的加工或服務(wù)。一個(gè)生產(chǎn)作業(yè)單位是多種工藝性質(zhì)的設(shè)備、工人等的集合體，進(jìn)行規(guī)定的各種工藝性質(zhì)的工或處理。它是借助于高度標(biāo)準(zhǔn)化的產(chǎn)品或服務(wù)及其所需用的高度標(biāo)準(zhǔn)化的作業(yè)得以實(shí)現(xiàn)的。一項(xiàng)工作被劃分成一系列的標(biāo)準(zhǔn)作業(yè)，以實(shí)現(xiàn)勞動(dòng)和設(shè)備的專業(yè)化。固定位置布置(Fixed-PositionLayout)產(chǎn)品或項(xiàng)目的位置保持不變，而人員、物料和設(shè)備在需要時(shí)移動(dòng)的布置。它與面向產(chǎn)品布置和面向工藝（過程）布置截然相反，是人員、物料和設(shè)備向“產(chǎn)品”移動(dòng)，而不是相反。產(chǎn)品的特點(diǎn)決定了這種布置，大的重量、尺寸、體積、以及其他因素致使產(chǎn)品或?qū)ο蟛贿m宜或極其難以移動(dòng)，而必須采用這種布置方式。JobShopLayoutEmergencyRoomLayoutSurgeryRadiologyE.R.bedsPharmacyBilling/exitE.R.TriageroomE.R.AdmissionsPatientB-erraticpacemakerPatientA-brokenlegHallwayRepetitiveLayout13245WorkOfficeBeltConveyorWorkStationNote:5tasksoroperations;3workstationsWorkStationStationStepsinDevelopinga

Process-OrientedLayoutConstructa“from-tomatrix”DeterminespacerequirementsforeachdepartmentDevelopaninitialschematicdiagramDeterminethecostofthislayoutBytrial-and-error(ormoresophisticatedmeans),trytoimprovetheinitiallayoutPrepareadetailedplanthatevaluatesfactorsinadditiontotransportationcostCostofProcess-OrientedLayout面向工藝布置，按已設(shè)計(jì)的工藝流程，根據(jù)工藝性質(zhì)的不同，劃分出若干個(gè)生產(chǎn)單位，然后確定各生產(chǎn)單位的相對(duì)空間位置。主要問題：確定各生產(chǎn)單位的相對(duì)位置，使其相互之間的總運(yùn)輸量或費(fèi)用最小，即InterdepartmentalFlowofParts:from-tomatrix12345612345650100002030501002001005000PossibleLayout1Room1 Room2 Room2Room4 Room5 Room6InterdepartmentalFlowGraphShowingNumberofWeeklyLoads11005030102050201005023456C=(50+200+40)+(30+50+10)+(40+100)+(50)=$570PossibleLayout2Room1 Room2 Room2Room4 Room5 Room6InterdepartmentalFlowGraphShowingNumberofWeeklyLoads21005030102050201005013456C=(50+100+20)+(60+50+10)+(40+100)+(50)=$480ComputerProgramstoAssistinLayoutCRAFTSPACECRAFTCRAFT3-DMULTIPLECORELAPALDEPCOFADFADES-expertsystemRelationshipChart1PresidentO2CostingUAA3EngineeringIO4President’sSecretary1234A=AbsolutelynecessaryE=EspeciallyimportantI=ImportantO=OrdinaryU=UnimportantX=NotDesirableProduct-OrientedRequirementsStandardizedproductHighproductionvolumeStableproductionquantitiesUniformqualityofrawmaterials&componentsProduct-OrientedLayoutTypesAssemblesfabricatedpartsUsesworkstationRepetitiveprocessPacedbytasksBalancedbymovingtasksBuildscomponentsUsesseriesofmachinesRepetitiveprocessMachinepacedBalancedbyphysicalredesignFabricationLineAssemblyLineAssemblyLineBalancingAnalysisofproductionlinesNearlyequallydividesworkbetweenworkstationswhilemeetingrequiredoutputObjectivesMaximizeefficiencyMinimizenumberof

workstationsAssemblyLineBalancingSteps1. Determinetasks(operations)2. Determinesequence3. Drawprecedencediagram4. Estimatetasktimes5. Calculatecycletime6. Assigntasks7. Calculatenumberofworkstations8. CalculateefficiencyAssemblyLineBalancingEquationsCycletime,CT=Productiontimeavailable

DemandperdayMinimumnumberofworkstationsTasktimesCycletimeNmin=Efficiency,BE=Tasktimes*(Cycletime)(Actualnumberofworkstations)BalanceDelay,BD=1—Tasktimes*(Cycletime)(Actualnumberofworkstations)可行的作業(yè)分配分配給每個(gè)工作地的作業(yè)，必須：（1）滿足作業(yè)之間的優(yōu)先(precedence)關(guān)系；（2）分配給每個(gè)工作地的作業(yè)的時(shí)間之和必須不大于周期時(shí)間。LayoutHeuristicsforAssigningTasksinAssemblyLineBalancingLongesttasktime-choosetaskwithlongestoperationtimeMostfollowingtasks-choosetaskwithlargestnumberoffollowingtasksRankedpositionalweight-choosetaskwherethesumofthetimesforeachfollowingtaskislongestShortesttasktime-choosetaskwithshortestoperationtimeLeastnumberoffollowingtasks-choosetaskwithfewestsubsequenttasksRandom–choosetaskrandomlyExleTaskABCDEFGHITime(min.)1011541237113Taskmustfollow--ABBAC,DFEG,HABEHCDFGI10Min.51112373411480productivemin.,complete40units,eachday.ExleExleC=12min.LongesttasktimeABEHCDFGI10Min.51112373411Exle:SixStationSolutionABCEDFGIH