EngineeringPlanningandProjectManagementLecture6ProjectTimeManagementEngineeringPlanningandProjeExamplefromIndustry–Motorola(TelecommunicationsEngineering)ReviewtheshorttextprovidedfromP.103-104ofPMBestPracticesBreakintoyourgroupsforafewminutesanddiscussthefollowingquestionspreparingaresponsewhichyoumaybeaskedtopresent.Question1:OneofthebulletitemsreferencedinMotorola’sdevelopmentofformalpracticesistheplanningandtrackingofresources.Besidespersonnel,givearealisticexampleofwhatelseMotorolamighttrack.Question2:Whatdoyouthink“complete”projectschedulingwouldimply?GiveexamplesofhowyouwouldintegrateittoyourprojectmanagementstrategyifyouwereaMotorolaPM.ExamplefromIndustry–MotorProjectSchedulingFirstyouneedtogeneratetheWorkBreakdownStructure(WBS)fortheprojectasdemonstrated.FromtheWBS,youneedtogeneratetheNetworkActivityDiagramfortheproject–commonlyreferredtoastheNetworkDiagram.ProjectSchedulingFirstyouneTheRulesforcreatingNetworkActivityDiagramsSomedeterminationofactivityprecedenceorderingmustbedonepriortocreatingthenetwork.Networkdiagramsusuallyflowfromlefttoright.Anactivitycannotbeginuntilallprecedingconnectedactivitieshavebeencompleted.Arrowsonnetworksindicateprecedenceandlogicalflow.Arrowscancrossovereachother,althoughitishelpfulforclarity’ssaketolimitthiseffectwhenpossible.Eachactivityshouldhaveauniqueidentifierassociatedwithit(number,letter,code,etc.).Looping,orrecyclingthroughactivities,isnotpermitted.Althoughnotrequired,itiscommontostartaprojectfromasinglebeginningnode.Asinglenodepointalsoistypicallyusedasaprojectendindicator.TheRulesforcreatingNetworkKeySchedulingTerminology-simplifiedScope–Theworkcontentandproductsofaproject.WorkBreakdownStructure(WBS)–Ataskorientedfamilytreeofactivitiesthatorganizes,defines,andgraphicallydisplaysthetotalworktobeaccomplishedinordertoachievethefinalobjectivesoftheproject.WorkPackage–Adeliverableatthelowestleveloftheworkbreakdownstructure.ProjectNetworkDiagram–Anyschematicdisplayofthelogicalrelationshipsofprojectactivities.Path–Asequenceofactivitiesdefinedbytheprojectnetworklogic.EarlyStartDate(ES)–Theearliestpossibledateonwhichtheuncompletedportionsofanactivitycanbecompleted.LateStartDate(LS)–Thelatestpossibledatethatanactivitymaybeginwithoutdelayingaspecifiedmilestone.KeySchedulingTerminology-sKeySchedulingTerminology–simplified(cont.)ForwardPass–Networkcalculationsthatdeterminetheearlieststart/finishtimeforeachactivity.BackwardPass–Calculationoflatefinishtimesforalluncompletednetworkactivities.Event–Apointintimewhenanactivityiseitherstartedorcompleted.Node–Oneormoredefiningpointsofanetwork.Predecessors–Thoseactivitiesthatmustbecompletedpriortoalateractivityinthenetwork.Successors–Activitiesthatcannotbestarteduntilpreviousactionshavebeencompleted.MergeActivity–Anactivitywith2ormoreimmediatesuccessoractivitiesflowingintoit.KeySchedulingTerminology–sKeySchedulingTerminology–simplified(cont.)BurstActivity–Anactivitywith2ormoreimmediatesuccessoractivitiesflowingoutfromit.Float

(Slack)–theamountoftimeanactivitymaybedelayedfromitsearlystartwithoutdelayingthefinishoftheproject.CriticalPath–Thepaththroughtheprojectnetworkwiththelongestduration.CriticalPathMethod–Anetworkanalysistechniqueusedtodeterminewhichsequenceofactivities(whichpath)hastheleastamountofschedulingflexibilityandthereforewillmostlikelydeterminewhentheprojectcanbecompleted.ResourceLimitedSchedule–Aprojectschedulewhosestartandfinishdatesreflectexpectedresourceavailability.ProgramEvaluationandReviewTool(PERT)–Aneventandprobabilitybasednetworkanalysissystemgenerallyusedinprojectswhereactivitiesandtheirdurationsaredifficulttodefine.KeySchedulingTerminology–sLabelsforActivityNodesLabelsforActivityNodesSeries/ParallelActivitiesSeries/ParallelActivitiesActivitiesMerge/BurstActivitiesMerge/BurstCreatingaProjectNetworkActivityDiagram-ExampleCreatingaProjectNetworkActActivityNetworkActivityNetworkActivityDurationEstimate–BetaEstimateActivityDurationEstimate–BConstructingtheCriticalPathConstructingtheCriticalPathProjectActivityNetworkShowingProjectDurationsProjectActivityNetworkShowiRuleswhenusingtheForwardPassRuleswhenusingtheForwardPActivityNetworkwithForwardPassActivityNetworkwithForwardRuleswhenusingtheBackwardPassRuleswhenusingtheBackwardActivityNetworkwithBackwardPassActivityNetworkwithBackwardCompletedNetworkActivityDiagram

withCriticalPathandSlackTimesCalculatedCriticalPathinboldCompletedNetworkActivityDiaNetworkActivityDiagramexamplethatIllustratesLadderingtechniqueLadderingistypicallyusedinsituationswhereonemightexpectaprogressiveloopintheprojectactivitiessuchascommonlyfoundinsoftwaredevelopment.NetworkActivityDiagramexampNetworkActivityDiagramexamplethatIllustratesHammockingtechniqueHammockingactivitiescanbeaddedassummariesfordiagramsegmentsofseriesactivities.Theycanformanagerialexplanationforexample,replacetheseriesofactivitiesbywhichtheyarebounded.Thisallowsforasmallerdiagram.NetworkActivityDiagramexampStepstoReducetheCriticalPathStepstoReducetheCriticalPResourceLevelingSometimesitisnecessarytomakethecriticalpathoftheprojectactuallylonger!Thistechniqueiscalledresourceleveling.Whileresourcelevelingdoesnotbydefinitionmandatelengtheningthecriticalpathitalmostalwaysdoes.Resourcelevelingiscarriedoutwhenaprojectresourcemustbeusedtoaddressscheduleactivitiesthatneedtobeperformedtomeetspecifieddeliverydates,ortoaddressasituationwheresharedorcriticalresourcesareonlyavailableatcertaintimesorinlimitedquantities.Resourcelevelingisalsousedtokeepselectedresourcesatconstantlevelsduringspecifictimesoftheprojectwork.ResourceLevelingSometimesitTheImpactofResourceLeveling–NetworkdiagramshownpriortoresourcelevelingbeingcarriedoutTheImpactofResourceLevelinTheImpactofResourceLeveling–showingtheleveladjustmentfor"design"thecriticalpathisstretched2daysTheImpactofResourceLevelinActivityDurationEstimatingThereareseveralmethods:Expertjudgmentestimating–Guidedbyhistoricalinformationthiscanbeusedwheneverpossible.Analogousestimating–Amethodofestimatingthatemploysusingasimilarscheduleactivityfromapreviousprojectasthebasisforestablishingthelikelydurationofafuturescheduleactivity.Parametricestimating–thequantityofworkmultipliedbytheproductivityrate.Forexamplelaborhourstodrawtimesnumberofhours,orcableinstallationinmetersofcabletimeslaborhourspermeter.Threepointmethod–PERTReserveanalysisestimating–Anoutputofriskanalysis,itcanbeemployedtoaddemptybuffersinprojecttimingtodealwithriskaspartofacontingencyplan.ActivityDurationEstimatingThLagsinPrecedenceRelationshipsThereare4commonlogicrelationshipsbetweentasks:

1)FinishtoStart

2)FinishtoFinish

3)StarttoStart

4)StarttoFinishLagsinPrecedenceRelationshiFinishtoStartFinishtoFinish31 S 33Plumbing233 T 36HVAC336 U 42InteriorConstructing630 R 36Wiring60 A 6Specdesign66 B 11DesignCheck515 C 22Blueprinting7Lag4FinishtoStartFinishtoFinisStarttoStartStarttoFinish31 S 33Plumbing233 T 36HVAC336 U 42InteriorConstructing633 R 39Wiring6Lag331 S 33Plumbing233 T 36HVAC336 U 42InteriorConstructing630 R 36Wiring6Lag3StarttoStartStarttoFinish3GanttchartsDevelopedbyHarveyGanttin1917,theyareanotherextremelyusefultoolforcreatingshowingaprojectnetwork.Ganttchartsestablishatime-phasednetwork,whichlinksprojectactivitiestoaprojectscheduleGanttchartsDevelopedbyHarveGanttChartsWhentheyarelinkedtoaprojectschedule,theycanbeusedtotracktheprogressoftheprojectagainstit'splan.SomeofthebenefitsofGanttChartsare:theyareeasytoreadandcomprehendtheyidentifytheprojectnetworkcoupledwiththescheduletheyallowforupdatingandprojectcontroltheyareusefulforassigningresourcestotaskstheyarealsoeasytocreate.GanttChartsWhentheyarelinkGanttChartTableversionGanttChartMSProjectversionGanttChartTableversionGanttAddingResourcestoGanttChartsCriticalPathcalculationAddingResourcestoGanttCharCRASHINGPROJECTS–UNDERWHATCONDITIONS?Theinitialschedulemaybetoooptimistic.Marketneedschangeandtheprojectisindemandearlierthananticipated.Theprojecthasslippedconsiderablybehindschedule.Thecontractualsituationprovidesevenmoreincentivetoavoidscheduleslippage.

CRASHINGPROJECTS–UNDERWHATOptionsforAcceleratingActivitiesImprovingtheproductivityofexistingprojectresources(teammeetingtofocuseffortsonthemostimportantaspectofatask.Reviewbestpracticehowtodothetask.)Changingtheworkingmethodemployedfortheactivity,usuallybyalteringthetechnologyandtypesofresourcesemployed(ChangefromdrawingreviewtoCADmodelreview)Increasingthequantityofprojectresources,includingpersonnel,plant,andequipment(OT,extrashifts,expeditefreight,...)OptionsforAcceleratingActivCautionwithrequesting(excessive)overtime!Thereisresearchthatsuggeststhatthegreatertheamountofovertimeworkersareexpectedtoperform,thelowerthemarginalperformanceacompanyislikelytoreceivefromthem.Forexample,itwasfoundthatinengineeringfunctions,optimalperformancewasrealizedafteronlyfourhoursofovertimeperweek.Bythetimeengineerswereworking10hrsofovertime,themarginalrealextraoutputrealizedbythecompanyhaddroppedtozero!Cautionwithrequesting(excesTime-CostTradeoffsforCrashingActivitiesTime-CostTradeoffsforCrashCRASHINGACTIVITIES–ANEXAMPLEFormula

Example–CalculatingtheCostofCrashingSUPPOSE:NORMALACTIVITYDURATION=8WEEKSNORMALCOST=$14,000CRASHEDACTIVITYDURATION=5WEEKSCRASHEDCOST=$23,000THEACTIVITYCOSTSLOPE=

23,000–14,000or,$9,000=$3,000perweek 8–5 3CRASHINGACTIVITIES–ANEXAMPProjectcostchangeswhentasksalongthecriticalpatharebeingcrashed.Thecostgoesupforeverytaskbeingcrashed.Onecancreateatablelistingalltasks,thenormaldurationandcost,andthecrasheddurationandcost.Withthistableitispossibletocalculatethecrashingcostperdayforeachtaskandselectthetaskthatmakesthemostfinancialsensetocrash.項目管理-Project-Time-Manage課件Crashingshowingcrashcost/dayCrashingshowingcrashcost/daWiththecostinformationpercrasheditem,andanetworkdiagramwecandeterminethetasksthatactuallyhaveaneffectontheoverallprojectdurationifcrashed.Thosetasksareonthecriticalpath.Notethatifataskgetscrashed.Theremainingnetworkdiagramhastobecheckedifthereisnowanewcriticalpath!Onecancalculatethereducedprojecttimeandincreasedcostforeachadditionalcost.Theresultwillbeaniterativeprocesswhereonetaskaftertheotherisbeingcrashed.Thisinformationcanbeplottedveryeasily.AllnormalCrashA+FCrashACrashA+F+JAllCrashedWiththecostinformationperInordertomakethebestfinancialsenseitisimportanttolookatthewholepicture.Usuallythedirectcostforaprojectgoup,whenitisbeingcrashed.Howeverthee.g.theoverheadcostorotherfixedcostisgoingdown.Alsotheprojectteamhastokeeppotentialpenaltiesinmind,iftheprojectexceedsacertainduration.Thisinformationisbestshowninagraphlikethefollowing.

InordertomakethebestfinaActivity-On-ArrowNetworksTaskIdnumberEarliesteventtimeLatesteventtimeActivity-On-ArrowNetworksTaskPARTIALAOANETWORKILLUSTRATINGDUMMYACTIVITIES

Thedummyactivitiesareusedfor"Finish-Start"Relationshipswhenthestartofonetaskdependsonthecompletionoftwoothertasks,whereonedependencydoesnotlieinthenetworkpathoftheactivity.Theydonothaveanyworkortimevaluesassignedtothem.PARTIALAOANETWORKILLUSTRATIControversiesintheuseofNetworksPERT/CPMiswellunderstoodandmuchemployed,neverthelessnetworksareanabstractrepresentationofeventswheretimeisreducedtoanumber.Theymayormaynotbedrawntoascalethathasarelationshiptoongoingpatternsortime.Thereareseveralcaveatweneedtokeepinmindwhenwedevelopprojectactivitynetworks:NetworkscanbecometoolargeandcomplextobemeaningfulFaultyreasoninginnetworkconstructioncansometimesleadtooversimplificationorincorrectrepresentations.NetworksaresometimesusedfortaskswhichtheyarenotwellsuitedNetworksusedtocontrolthebehaviorofsubcontractorshavespecialdangers.ThereisastrongpotentialforpositivebiasinPERTestimationsusedinnetworkconstruction.ControversiesintheuseofNeMonteCarloMethod/url?q=/~kwak/Monte_Carlo_Kwak_Ingall.pdf&sa=U&ei=TzW2TZ-TLs65tgf4qsCLAQ&ved=0CBEQFjAA&usg=AFQjCNEagFyBi29MVaNcMrmls76tUQcfoATheabovelinkgivesagoodreviewofMonteCarlomethod.MonteCarloMethodisusedinProjectmanagementforrisk,cost,andtimeestimations.Generallyitismostpopularforriskcalculations,butyouwillseeitisveryusefulfortimeestimatesaswell.MonteCarloMethodhttp://www.gMilestonesMilestonesEngineeringPlanningandProjectManagementLecture6ProjectTimeManagementEngineeringPlanningandProjeExamplefromIndustry–Motorola(TelecommunicationsEngineering)ReviewtheshorttextprovidedfromP.103-104ofPMBestPracticesBreakintoyourgroupsforafewminutesanddiscussthefollowingquestionspreparingaresponsewhichyoumaybeaskedtopresent.Question1:OneofthebulletitemsreferencedinMotorola’sdevelopmentofformalpracticesistheplanningandtrackingofresources.Besidespersonnel,givearealisticexampleofwhatelseMotorolamighttrack.Question2:Whatdoyouthink“complete”projectschedulingwouldimply?GiveexamplesofhowyouwouldintegrateittoyourprojectmanagementstrategyifyouwereaMotorolaPM.ExamplefromIndustry–MotorProjectSchedulingFirstyouneedtogeneratetheWorkBreakdownStructure(WBS)fortheprojectasdemonstrated.FromtheWBS,youneedtogeneratetheNetworkActivityDiagramfortheproject–commonlyreferredtoastheNetworkDiagram.ProjectSchedulingFirstyouneTheRulesforcreatingNetworkActivityDiagramsSomedeterminationofactivityprecedenceorderingmustbedonepriortocreatingthenetwork.Networkdiagramsusuallyflowfromlefttoright.Anactivitycannotbeginuntilallprecedingconnectedactivitieshavebeencompleted.Arrowsonnetworksindicateprecedenceandlogicalflow.Arrowscancrossovereachother,althoughitishelpfulforclarity’ssaketolimitthiseffectwhenpossible.Eachactivityshouldhaveauniqueidentifierassociatedwithit(number,letter,code,etc.).Looping,orrecyclingthroughactivities,isnotpermitted.Althoughnotrequired,itiscommontostartaprojectfromasinglebeginningnode.Asinglenodepointalsoistypicallyusedasaprojectendindicator.TheRulesforcreatingNetworkKeySchedulingTerminology-simplifiedScope–Theworkcontentandproductsofaproject.WorkBreakdownStructure(WBS)–Ataskorientedfamilytreeofactivitiesthatorganizes,defines,andgraphicallydisplaysthetotalworktobeaccomplishedinordertoachievethefinalobjectivesoftheproject.WorkPackage–Adeliverableatthelowestleveloftheworkbreakdownstructure.ProjectNetworkDiagram–Anyschematicdisplayofthelogicalrelationshipsofprojectactivities.Path–Asequenceofactivitiesdefinedbytheprojectnetworklogic.EarlyStartDate(ES)–Theearliestpossibledateonwhichtheuncompletedportionsofanactivitycanbecompleted.LateStartDate(LS)–Thelatestpossibledatethatanactivitymaybeginwithoutdelayingaspecifiedmilestone.KeySchedulingTerminology-sKeySchedulingTerminology–simplified(cont.)ForwardPass–Networkcalculationsthatdeterminetheearlieststart/finishtimeforeachactivity.BackwardPass–Calculationoflatefinishtimesforalluncompletednetworkactivities.Event–Apointintimewhenanactivityiseitherstartedorcompleted.Node–Oneormoredefiningpointsofanetwork.Predecessors–Thoseactivitiesthatmustbecompletedpriortoalateractivityinthenetwork.Successors–Activitiesthatcannotbestarteduntilpreviousactionshavebeencompleted.MergeActivity–Anactivitywith2ormoreimmediatesuccessoractivitiesflowingintoit.KeySchedulingTerminology–sKeySchedulingTerminology–simplified(cont.)BurstActivity–Anactivitywith2ormoreimmediatesuccessoractivitiesflowingoutfromit.Float

(Slack)–theamountoftimeanactivitymaybedelayedfromitsearlystartwithoutdelayingthefinishoftheproject.CriticalPath–Thepaththroughtheprojectnetworkwiththelongestduration.CriticalPathMethod–Anetworkanalysistechniqueusedtodeterminewhichsequenceofactivities(whichpath)hastheleastamountofschedulingflexibilityandthereforewillmostlikelydeterminewhentheprojectcanbecompleted.ResourceLimitedSchedule–Aprojectschedulewhosestartandfinishdatesreflectexpectedresourceavailability.ProgramEvaluationandReviewTool(PERT)–Aneventandprobabilitybasednetworkanalysissystemgenerallyusedinprojectswhereactivitiesandtheirdurationsaredifficulttodefine.KeySchedulingTerminology–sLabelsforActivityNodesLabelsforActivityNodesSeries/ParallelActivitiesSeries/ParallelActivitiesActivitiesMerge/BurstActivitiesMerge/BurstCreatingaProjectNetworkActivityDiagram-ExampleCreatingaProjectNetworkActActivityNetworkActivityNetworkActivityDurationEstimate–BetaEstimateActivityDurationEstimate–BConstructingtheCriticalPathConstructingtheCriticalPathProjectActivityNetworkShowingProjectDurationsProjectActivityNetworkShowiRuleswhenusingtheForwardPassRuleswhenusingtheForwardPActivityNetworkwithForwardPassActivityNetworkwithForwardRuleswhenusingtheBackwardPassRuleswhenusingtheBackwardActivityNetworkwithBackwardPassActivityNetworkwithBackwardCompletedNetworkActivityDiagram

withCriticalPathandSlackTimesCalculatedCriticalPathinboldCompletedNetworkActivityDiaNetworkActivityDiagramexamplethatIllustratesLadderingtechniqueLadderingistypicallyusedinsituationswhereonemightexpectaprogressiveloopintheprojectactivitiessuchascommonlyfoundinsoftwaredevelopment.NetworkActivityDiagramexampNetworkActivityDiagramexamplethatIllustratesHammockingtechniqueHammockingactivitiescanbeaddedassummariesfordiagramsegmentsofseriesactivities.Theycanformanagerialexplanationforexample,replacetheseriesofactivitiesbywhichtheyarebounded.Thisallowsforasmallerdiagram.NetworkActivityDiagramexampStepstoReducetheCriticalPathStepstoReducetheCriticalPResourceLevelingSometimesitisnecessarytomakethecriticalpathoftheprojectactuallylonger!Thistechniqueiscalledresourceleveling.Whileresourcelevelingdoesnotbydefinitionmandatelengtheningthecriticalpathitalmostalwaysdoes.Resourcelevelingiscarriedoutwhenaprojectresourcemustbeusedtoaddressscheduleactivitiesthatneedtobeperformedtomeetspecifieddeliverydates,ortoaddressasituationwheresharedorcriticalresourcesareonlyavailableatcertaintimesorinlimitedquantities.Resourcelevelingisalsousedtokeepselectedresourcesatconstantlevelsduringspecifictimesoftheprojectwork.ResourceLevelingSometimesitTheImpactofResourceLeveling–NetworkdiagramshownpriortoresourcelevelingbeingcarriedoutTheImpactofResourceLevelinTheImpactofResourceLeveling–showingtheleveladjustmentfor"design"thecriticalpathisstretched2daysTheImpactofResourceLevelinActivityDurationEstimatingThereareseveralmethods:Expertjudgmentestimating–Guidedbyhistoricalinformationthiscanbeusedwheneverpossible.Analogousestimating–Amethodofestimatingthatemploysusingasimilarscheduleactivityfromapreviousprojectasthebasisforestablishingthelikelydurationofafuturescheduleactivity.Parametricestimating–thequantityofworkmultipliedbytheproductivityrate.Forexamplelaborhourstodrawtimesnumberofhours,orcableinstallationinmetersofcabletimeslaborhourspermeter.Threepointmethod–PERTReserveanalysisestimating–Anoutputofriskanalysis,itcanbeemployedtoaddemptybuffersinprojecttimingtodealwithriskaspartofacontingencyplan.ActivityDurationEstimatingThLagsinPrecedenceRelationshipsThereare4commonlogicrelationshipsbetweentasks:

1)FinishtoStart

2)FinishtoFinish

3)StarttoStart

4)StarttoFinishLagsinPrecedenceRelationshiFinishtoStartFinishtoFinish31 S 33Plumbing233 T 36HVAC336 U 42InteriorConstructing630 R 36Wiring60 A 6Specdesign66 B 11DesignCheck515 C 22Blueprinting7Lag4FinishtoStartFinishtoFinisStarttoStartStarttoFinish31 S 33Plumbing233 T 36HVAC336 U 42InteriorConstructing633 R 39Wiring6Lag331 S 33Plumbing233 T 36HVAC336 U 42InteriorConstructing630 R 36Wiring6Lag3StarttoStartStarttoFinish3GanttchartsDevelopedbyHarveyGanttin1917,theyareanotherextremelyusefultoolforcreatingshowingaprojectnetwork.Ganttchartsestablishatime-phasednetwork,whichlinksprojectactivitiestoaprojectscheduleGanttchartsDevelopedbyHarveGanttChartsWhentheyarelinkedtoaprojectschedule,theycanbeusedtotracktheprogressoftheprojectagainstit'splan.SomeofthebenefitsofGanttChartsare:theyareeasytoreadandcomprehendtheyidentifytheprojectnetworkcoupledwiththescheduletheyallowforupdatingandprojectcontroltheyareusefulforassigningresourcestotaskstheyarealsoeasytocreate.GanttChartsWhentheyarelinkGanttChartTableversionGanttChartMSProjectversionGanttChartTableversionGanttAddingResourcestoGanttChartsCriticalPathcalculationAddingResourcestoGanttCharCRASHINGPROJECTS–UNDERWHATCONDITIONS?Theinitialschedulemaybetoooptimistic.Marketneedschangeandtheprojectisindemandearlierthananticipated.Theprojecthasslippedconsiderablybehindschedule.Thecontractualsituationprovidesevenmoreincentivetoavoidscheduleslippage.

CRASHINGPROJECTS–UNDERWHATOptionsforAcceleratingActivitiesImprovingtheproductivityofexistingprojectresources(teammeetingtofocuseffortsonthemostimportantaspectofatask.Reviewbestpracticehowtodothetask.)Changingtheworkingmethodemployedfortheactivity,usuallybyalteringthetechnologyandtypesofresourcesemployed(ChangefromdrawingreviewtoCADmodelreview)Increasingthequantityofprojectresources,includingpersonnel,plant,andequipment(OT,extrashifts,expeditefreight,...)OptionsforAcceleratingActivCautionwithrequesting(excessive)overtime!Thereisresearchthatsuggeststhatthegreatertheamountofovertimeworkersareexpectedtoperform,thelowerthemarginalperformanceacompanyislikelytoreceivefromthem.Forexample,itwasfoundthatinengineeringfunctions,optimalperformancewasrealizedafteronlyfourhoursofovertimeperweek.Bythetimeengineerswereworking10hrsofovertime,themarginalrealextraoutputrealizedbythecompanyhaddroppedtozero!Cautionwithrequesting(excesTime-CostTradeoffsforCrashingActivitiesTime-CostTradeoffsforCrashCRASHINGACTIVITIES–ANEXAMPLEFormula

Example–CalculatingtheCostofCrashingSUPPOSE:NORMALACTIVITYDURATION=8WEEKSNORMALCOST=$14,000CRASHEDACTIVITYDURATION=5WEEKSCRASHEDCOST=$23,000THEACTIVITYCOSTSLOPE=

23,000–14,000or,$9,000=$3,000perweek 8–5 3CRASHINGACTIVITIES–ANEXAMPProjectcostchangeswhentasksalongthecriticalpatharebeingcrashed.Thecostgoesupforeverytaskbeingcrashed.Onecancreateatablelistingalltasks,thenormaldurationandcost,andthecrasheddurationandcost.Withthistableitispossibletocalculatethecrashingcostperdayforeachtaskandselectthetaskthatmakesthemostfinancialsensetocrash.項目管理-Project-Time-Manage課件Crashing