Lecture Outline

Copyright 2006 John Wiley & Sons, Inc.Project SchedulingStepsDefine activitiesSequence activitiesEstimate timeDevelop scheduleTechniquesGantt chartCPMPERTDSMCopyright 2006 John Wiley & Sons, Inc.Gantt ChartGraph or bar chart with a bar for each project activity that shows passage of timeProvides visual display of project scheduleSlackamount of time an activity can be delayed without delaying the project

Copyright 2006 John Wiley & Sons, Inc.|||||Activity

Design house and obtain financing

Lay foundation

Order and receive materials

Build house

Select paint

Select carpet

Finish work0246810MonthMonth13579Example of Gantt ChartCopyright 2006 John Wiley & Sons, Inc.CPM/PERTCritical Path Method (CPM)DuPont & Remington-Rand (1956)Deterministic task timesActivity-on-node network constructionProject Evaluation and Review Technique (PERT)US Navy, Booz, Allen & HamiltonMultiple task time estimatesActivity-on-arrow network constructionCopyright 2006 John Wiley & Sons, Inc.Project NetworkActivity-on-node (AON)nodes represent activities, and arrows show precedence relationshipsActivity-on-arrow (AOA)arrows represent activities and nodes are events for points in timeEvent completion or beginning of an activity in a projectACBBranchNodeCopyright 2006 John Wiley & Sons, Inc.AOA Project Network for a House32013111ABDFGCELay foundationDesign house and obtain financingOrder and receive materialsDummyFinish workSelect carpetSelect paintBuild houseCopyright 2006 John Wiley & Sons, Inc.Concurrent ActivitiesBCLay foundationOrder material(a)Incorrect precedence relationship(b)Correct precedence relationshipCDBDummyLay foundationOrder material120Copyright 2006 John Wiley & Sons, Inc.AON Network for House Building ProjectA3B2D3C1E1F1G1StartDesign house and obtain financingOrder and receive materialsSelect paintSelect carpetLay foundationsBuild houseFinish workCopyright 2006 John Wiley & Sons, Inc.A3B2D3C1E1F1G1StartCritical PathCritical pathLongest path through a networkMinimum project completion time1:A-B-D-G3 + 2 + 3 + 1 = 9 months 2:A-B-E-F-G3 + 2 + 1 + 1 + 1 = 8 months3:A-C-D-G3 + 1 + 3 + 1 = 8 months4:A-C-E-F-G3 + 1 + 1 + 1 + 1 = 7 monthsCopyright 2006 John Wiley & Sons, Inc.Activity Start TimesA3B2D3C1E1F1G1StartStart at 3 monthsStart at 6 monthsStart at 5 monthsFinish at 9 monthsFinishCopyright 2006 John Wiley & Sons, Inc.Mode ConfigurationActivity numberActivity durationEarliest startLatest startEarliest finishLatest finishESIDEFSLSLLSDURLFSlack Slack Copyright 2006 John Wiley & Sons, Inc.Forward PassStart at the beginning of CPM/PERT network to determine the earliest activity timesEarliest Start Time (ES)earliest time an activity can start ES = maximum EF of immediate predecessorsEarliest finish time (EF)earliest time an activity can finishearliest start time plus activity timeEF= ES + tCopyright 2006 John Wiley & Sons, Inc.StartFinish B2A3D3G1F1E1C1Earliest Activity Start and Finish TimesEarliest Activity Start and Finish TimesStartFinish3 B520A335D838G916F715E613C41Copyright 2006 John Wiley & Sons, Inc.Copyright 2006 John Wiley & Sons, Inc.Backward PassDetermines latest activity times by starting at the end of CPM/PERT network and working forwardLatest Start Time (LS)Latest time an activity can start without delaying critical path time LS= LF - tLatest finish time (LF)latest time an activity can be completed without delaying critical path timeLS = minimum LS of immediate predecessorsLatest Activity Start and Finish TimesStartFinish3 B53250A30335D85388G98196F77185E66173C4415Copyright 2006 John Wiley & Sons, Inc.Copyright 2006 John Wiley & Sons, Inc.StartFinish3 B5003250A3000335D8005388G9008196F7117185E6116173C411415Slack or floatExample 1Finish to Start Dependency

Start to Start Dependency

Start to Start Dependency0A40440B8088Start to Start Dependency0A40442B102810Lag 2Finish to Finish Dependency

Finish to Finish Dependency0A40442B4224Finish to Finish Dependency0A40444B6426Lag 2Start to Finish Dependency

Start to Finish Dependency5A95493B5325Start to Finish Dependency5A95495B7527Lag 2