数据、模型与决策（第12版）课件 第8章项目管理

ProjectManagementChapter8Copyright©2016PearsonEducation,Inc.TheElementsofProjectManagementProbabilisticActivityTimesMicrosoftProjectProjectCrashingandTime-CostTrade-OffFormulatingtheCPM/PERTNetworkasaLinearProgrammingModelChapterTopicsCopyright©2016PearsonEducation,Inc.Networkrepresentationisusefulforprojectanalysis.Networksshowhowprojectactivitiesareorganizedandareusedtodeterminetimedurationofprojects.Networktechniquesusedare:CPM(CriticalPathMethod)PERT(ProjectEvaluationandReviewTechnique)Developedindependentlyduringlate1950s.OverviewCopyright©2016PearsonEducation,Inc.ElementsofProjectManagementManagementisgenerallyperceivedasconcernedwithplanning,organizing,andcontrolofanongoingprocessoractivity.Projectmanagementisconcernedwithcontrolofanimportantactivityforarelativelyshortperiodoftimeafterwhichmanagementeffortends.Primaryelementsofprojectmanagementtobediscussed:ProjectPlanningProjectReturnProjectTeamProjectControlCopyright©2016PearsonEducation,Inc.ElementsofProjectManagementProjectPlanningObjectivesProjectscopeContractrequirementsSchedulesResourcesPersonnelControlRiskandproblemanalysisCopyright©2016PearsonEducation,Inc.Figure8.1TheprojectmanagementprocessTheProjectManagementProcessCopyright©2016PearsonEducation,Inc.ElementsofProjectManagementProjectReturnReturnoninvestment(ROI)isameasureusedtoevaluateprojectscalculatedbydividingthedollargainminusthedollarcostbythedollarcost.ROIcanbeusedtorankprojectsNotallprojectbenefitscanbemeasuredindollarsCopyright©2016PearsonEducation,Inc.Projectteamtypicallyconsistsofagroupofindividualsfromvariousareasinanorganizationandoftenincludesoutsideconsultants.Membersofengineeringstaffoftenassignedtoprojectwork.Projectteammayincludeworkers.Mostimportantmemberofprojectteamistheprojectmanager.Projectmanagerisoftenundergreatpressurebecauseofuncertaintyinherentinprojectactivitiesandpossibilityoffailure.Potentialrewards,however,canbesubstantial.Projectmanagermustbeabletocoordinatevariousskillsofteammembersintoasinglefocusedeffort.ElementsofProjectManagementTheProjectTeamCopyright©2016PearsonEducation,Inc.ElementsofProjectManagementScopeStatementDocumentprovidingcommonunderstandingofproject.Justificationdescribingthefactorsgivingrisetoneedforproject.Expectedresultsandwhatconstitutessuccess.Listofnecessarydocumentsandplanningreports.Statementofwork(SOW)-aplanningdocumentforindividuals,teammembers,groups,departments,subcontractorsandsuppliers,describingwhatarerequiredforsuccessfulcompletionontime.Copyright©2016PearsonEducation,Inc.ElementsofProjectManagement

WorkBreakdownStructure(WBS)(1of2)WBSbreaksdownprojectintomajorcomponents(modules).Modulesarefurtherbrokendownintoactivitiesand,finally,intoindividualtasks.Identifiesactivities,tasks,resourcerequirementsandrelationshipsbetweenmodulesandactivities.Helpsavoidduplicationofeffort.Basisforprojectdevelopment,management,schedule,resourcesandmodifications.ApproachesforWBSdevelopment: 1.Topdownprocess2.BrainstormentireprojectCopyright©2016PearsonEducation,Inc.Figure8.2WBSforcomputerorder-processingsystemprojectElementsofProjectManagement

WorkBreakdownStructure(2of2)Copyright©2016PearsonEducation,Inc.ElementsofProjectManagementResponsibilityAssignmentMatrix(1of2)

RAMshowswhoisresponsiblefordoingthenecessaryworkintheprojectProjectmanagerassignsworkelementstoorganizationalunits,departments,groups,individualsorsubcontractors.Usesanorganizationalbreakdownstructure(OBS).OBSisatableorachartshowingwhichorganizationalunitsareresponsibleforworkitems.OBSleadstotheresponsibilityassignmentmatrix(RAM)

Copyright©2016PearsonEducation,Inc.ElementsofProjectManagementResponsibilityAssignmentMatrix(2of2)

Figure8.3AresponsibilityassignmentmatrixCopyright©2016PearsonEducation,Inc.ElementsofProjectManagementProjectSchedulingProjectscheduleevolvesfromplanningdocuments,withfocusontimelycompletion.Criticalelementinprojectmanagement–sourceofmostconflictsandproblems.Scheduledevelopmentsteps: 1.Defineactivities, 2.Sequenceactivities, 3.Estimateactivitytimes, 4.Developschedule.GanttchartandCPM/PERTtechniquescanbeuseful.Computersoftwarepackagesavailable,e.g.MicrosoftProject.Copyright©2016PearsonEducation,Inc.ElementsofProjectManagementGanttChart(1of2)Popular,traditionaltechnique,alsoknownasabarchart-developedbyHenryGantt(1914).DirectprecursorofCPM/PERTformonitoringworkprogress.Avisualdisplayofprojectscheduleshowingactivitystartandfinishtimesandwhereextratimeisavailable.Suitableforprojectswithfewactivitiesandprecedencerelationships.Drawback:precedencerelationshipsarenotalwaysdiscerniblewhichlimitschart’suseforsmallerprojectsCopyright©2016PearsonEducation,Inc.ElementsofProjectManagementGanttChart(2of2)Figure8.4AGanttchartCopyright©2016PearsonEducation,Inc.ElementsofProjectManagementProjectControlProcessof

ensuringprogresstowardsuccessfulcompletion.Monitoringprojecttominimizedeviationsfromprojectplanandschedule.Correctiveactionsnecessaryifdeviationsoccur.KeyelementsofprojectcontrolTimemanagementCostmanagementPerformancemanagementEarnedvalueanalysis(EVA)Abranchreflectsanactivityofaproject.Anoderepresentsthebeginningandendofactivities,referredtoasevents.Branchesinthenetworkindicateprecedencerelationships.Whenanactivityiscompletedatanode,ithasbeenrealized.TheProjectNetworkCPM/PERTFigure8.5NodesandbranchesActivity-on-Arc(AOA)NetworkCopyright©2016PearsonEducation,Inc.TheProjectNetwork

HouseBuildingProjectDataNumberActivityPredecessorDuration1Designhouseandobtainfinancing--3months2Layfoundation12months3Orderandreceivematerials11month4Buildhouse2,33months5Selectpaint2,31month6Selectcarper51month7Finishwork4,61monthActivitiescanoccuratthesametime(concurrently).Networkaidsinplanningandscheduling.Timedurationofactivitiesshownonbranches.TheProjectNetworkConcurrentActivitiesFigure8.6Concurrentactivitiesforhouse-buildingprojectAdummyactivityshowsaprecedencerelationshipbutreflectsnopassageoftime.Twoormoreactivitiescannotsharethesamestartandendnodes.TheProjectNetworkDummyActivitiesFigure8.7AdummyactivityCopyright©2016PearsonEducation,Inc.TheProjectNetworkAONNetworkforHouseBuildingProjectActivity-on-Node(AON)Network

Anoderepresentsanactivity,withitslabelandtimeshownonthenodeThebranchesshowtheprecedencerelationshipsConventionusedinMicrosoftProjectsoftwareFigure8.8AONnetworkCopyright©2016PearsonEducation,Inc.

TheProjectNetworkPathsThroughaNetworkTable8.1Pathsthroughthehouse-buildingnetworkPathEventsA1247B12567C1347D13567Copyright©2016PearsonEducation,Inc.Thecriticalpath

isthelongestpaththroughthenetwork;theminimumtimethenetworkcanbecompleted.FromFigure8.8:PathA:1

2

4

7 3+2+3+1=9monthsPathB:1

2

5

6

7 3+2+1+1+1=8monthsPathC:1

3

4

7 3+1+3+1=8monthsPathD:1

3

5

6

7 3+1+1+1+1=7monthsTheProjectNetworkTheCriticalPathTheProjectNetworkActivityStartTimesFigure8.9ActivitystarttimeCopyright©2016PearsonEducation,Inc.TheProjectNetwork

ActivitySchedulinginActivity-on-NodeConfigurationFigure8.10Activity-on-nodeconfigurationESistheearliesttimeanactivitycanstart:EFistheearlieststarttimeplustheactivitytime:TheProjectNetworkActivityScheduling:EarliestTimesFigure8.11EarliestactivitystartandfinishtimesLSisthelatesttimeanactivitycanstartwithoutdelayingcriticalpathtime:TheProjectNetworkActivityScheduling:LatestTimesFigure8.12LatestactivitystartandfinishtimesLFisthelatestfinishtime:Slack

istheamountoftimeanactivitycanbedelayedwithoutdelayingtheproject:S=LS–ES=LF-EFSlackTimeexistsforthoseactivitiesnotonthecriticalpathforwhichtheearliestandlateststarttimesarenotequal.SharedSlackisslackavailableforasequenceofactivities.TheProjectNetworkActivitySlackTime(1of2)Table8.2ActivitySlack*CriticalpathActivityLSESLFEFSlack,S*100330*233550343541*455880565761676871*788990TheProjectNetworkActivitySlackTime(2of2)Figure8.13ActivityslackCopyright©2016PearsonEducation,Inc.Activitytimeestimatesusuallycannotbemadewithcertainty.PERTusedforprobabilisticactivitytimes.InPERT,threetimeestimatesareused:mostlikely

time(m),theoptimistictime(a),andthepessimistictime(b).Theseprovideanestimateofthemeanandvarianceofabetadistribution: variance:

mean(expectedtime):ProbabilisticActivityTimesProbabilisticActivityTimesExample(1of3)Figure8.14Networkfororderprocessingsysteminstallation

ProbabilisticActivityTimesExample(2of3)Table8.3ActivitytimeestimatesforFigure8.14ProbabilisticActivityTimesExample(3of3)Figure8.15EarliestandlatestactivitytimesExpectedprojecttimeisthesumoftheexpectedtimesofthecriticalpathactivities.Projectvarianceisthesumofthecriticalpathactivities’variancesTheexpectedprojecttimeisassumedtobenormallydistributed(basedoncentrallimittheorem).Inexample,expectedprojecttime(tp)andvariance(vp)interpretedasthemean()andvariance(2)ofanormaldistribution:=25weeks

2=62/9=6.9weeks2ProbabilisticActivityTimesExpectedProjectTimeandVarianceCopyright©2016PearsonEducation,Inc.Usingthenormaldistribution,probabilitiesaredeterminedbycomputingthenumberofstandarddeviations(Z)avalueisfromthemean.TheZvalueisusedtofindthecorrespondingprobabilityinTableA.1,AppendixA.ProbabilityAnalysisofaProjectNetwork(1of2)Copyright©2016PearsonEducation,Inc.ProbabilityAnalysisofaProjectNetwork(2of2)Figure8.16NormaldistributionofnetworkdurationCopyright©2016PearsonEducation,Inc.ProbabilityAnalysisofaProjectNetworkExample1(1of2)Figure8.17Probabilitythatthenetworkwillbecompletedin30weeksorlessCopyright©2016PearsonEducation,Inc. Whatistheprobabilitythattheneworderprocessingsystemwillbereadyby30weeks?ProbabilityAnalysisofaProjectNetworkExample1(2of2)Zvalueof1.90correspondstoprobabilityof.4713inTableA.1,AppendixA.Theprobabilityofcompletingprojectin30weeksorless:(.5000+.4713)=.9713.Copyright©2016PearsonEducation,Inc.ProbabilityAnalysisofaProjectNetworkExample2(1of2)Figure8.18Probabilitythenetworkwillbecompletedin22weeksorlessCopyright©2016PearsonEducation,Inc.Acustomerwilltradeelsewhereiftheneworderingsystemisnotworkingwithin22weeks.Whatistheprobabilitythatshewillberetained?Z=(22-25)/2.63=-1.14Zvalueof1.14(ignorenegative)correspondstoprobabilityof.3729inTableA.1,AppendixA.Probabilitythatcustomerwillberetainedis.1271(.5000-.3729)

ProbabilityAnalysisofaProjectNetworkExample2(2of2)Copyright©2016PearsonEducation,Inc.CPM/PERTAnalysiswith

QMforWindows&ExcelQM(1of2)Exhibit8.1:QMforWindowssolutionoutputforsysteminstallationCPM/PERTAnalysiswithQMforWindows&ExcelQM(2of2)Exhibit8.2:ExcelQMsolutionInputtimeestimatesInputactivitypredecessorsMicrosoftProjecthandlesonlyAONnetworks.AnalysiswithMicrosoftProject(1of6)Exhibit8.3GanttcharttoolsCreateprecedencerelationshipsbytypinginpredecessoractivities,separatedbycommas,orbyclickingon“link”iconStartdateActivityduration,i.e.,“3mo”ActivitynameAnalysiswithMicrosoftProject(2of6)Exhibit8.4ChangetimescaleClickon“EntireProject”tofitGanttchartonscreenPredecessoractivities;separatedbycommasifmorethanoneRight-clickontimelinetochangescaleAnalysiswithMicrosoftProject(3of6)Exhibit8.5Select“CriticalTasks”tohighlightcriticalpathCriticalactivitieshighlightedinredAnalysiswithMicrosoftProject(4of6)Exhibit8.6Click“Zoom”tomakenetworklargerorsmalleronscreenClicktogetnetworkAnalysiswithMicrosoftProject(5of6)Exhibit8.7AnalysiswithMicrosoftProject(6of6)Exhibit8.8Clickon“NetworkDiagram”togetnetworkCriticalpathinredCopyright©2016PearsonEducation,Inc.Projectdurationcanbereducedbyassigningmoreresourcestoprojectactivities.However,doingthisincreasesprojectcost.Decisionisbasedonanalysisoftrade-offbetweentimeandcost.Projectcrashing

isamethodforshorteningprojectdurationbyreducingoneormorecriticalactivitiestoatimelessthannormalactivitytime.ProjectCrashingandTime-CostTrade-OffOverviewProjectCrashingandTime-CostTrade-OffExampleProblem(1of5)Figure8.19TheprojectnetworkforbuildingahouseCopyright©2016PearsonEducation,Inc.ProjectCrashingandTime-CostTrade-OffExampleProblem(2of5)Figure8.20Time-costrelationshipforcrashingactivity1Crashcost&crashtimehavealinearrelationship:Table8.4NormalactivityandcrashdatafortheFig8.19networkProjectCrashingandTime-CostTrade-OffExampleProblem(3of5)Figure8.21NetworkwithnormalactivitytimesandweeklycrashingcostsProjectCrashingandTime-CostTrade-OffExampleProblem(4of5)Figure8.22Revisednetworkwithactivity1crashedProjectCrashingandTime-CostTrade-OffExampleProblem(5of5) Asactivitiesarecrashed,thecriticalpathmaychangeandseveralpathsmaybecomecritical.Exhibit8.9ProjectCrashingandTime-CostTrade-OffQMforWindowsCopyright©2016PearsonEducation,Inc.ProjectCrashingandTime-CostTrade-OffGeneralRelationshipofTimeandCost(1of2)Projectcrashingcostsandindirectcostshaveaninverserelationship.Crashingcostsarehighestwhentheprojectisshortened.Indirectcostsincreaseastheprojectdurationincreases.Theoptimalprojecttimeisattheminimumpointonthetotalcostcurve.Copyright©2016PearsonEducation,Inc.ProjectCrashingandTime-CostTrade-OffGeneralRelationshipofTimeandCost(2of2)Figure8.23Thetime-costtrade-offCopyright©2016PearsonEducation,Inc.GenerallinearprogrammingmodelwithAOAconventionTheobjectiveistominimizetheprojectduration(criticalpathtime).TheCPM/PERTNetworkFormulatingasaLinearProgrammingModelCopyright©2016PearsonEducation,Inc.TheCPM/PERTNetworkExampleProblemFormulationandData(1of2)Figure8.24CPM/PERTnetworkwithearliesteventtimesCopyright©2016PearsonEducation,Inc.MinimizeZ=x1+x2+x3+x4+x5+x6+x7subjectto: x2-x1

12 x3-x2

8 x4-x2

4 x4-x3

0 x5-x4

4 x6-x4

12 x6-x5

4 x7-x6

4 xi,xj

0TheCPM/PERTNetworkExampleProblemFormulationandData(2of2)Copyright©2016PearsonEducation,Inc.Exhibit8.10TheCPM/PERTNetworkExampleProblemSolutionwithExcel(1of4)B6:B12=B7-B6Decisionvariables,B6:B12Copyright©2016PearsonEducation,Inc.Exhibit8.11TheCPM/PERTNetworkExampleProblemSolutionwithExcel(2of4)Copyright©2016PearsonEducation,Inc.Exhibit8.12TheCPM/PERTNetworkExampleProblemSolutionwithExcel(3of4)Copyright©2016PearsonEducation,Inc.Exhibit8.13Sensitivityreportforhouse-buildingprojectTheCPM/PERTNetworkExampleProblemSolutionwithExcel(4of4)Ashadowpriceof1indicatescriticalpathCopyright©2016PearsonEducation,Inc.MinimizeZ=$400y12+500y23+3000y24+200y45+7000y46 +200y56+7000y67subjectto: y12

5 y12+x2-x1

12 x7

30 y23

3 y23+x3-x2

8 xi,yij≥0 y24

1 y24+x4-x2

4 y34

0 y34+x4-x3

0 y45

3 y45+x5-x4

4 y46

3 y46+x6-x4

12 y56

3 y56+x6-x5

4

y67

1

x67+x7-x6

4xi=earliesteventtimeofnodeIxj=earliesteventtimeofnodejyij=amountoftimebywhichactivityi

jiscrashedProjectCrashingwithLinearProgrammingExampleProblem–ModelFormulationTheobjectiveistominimizethecostofcrashingCopyright©2016PearsonEducation,Inc.ProjectCrashingwithLinearProgrammingExcelSolution(1of3)Exh