Project Management in Practice Third Edition

PROJECT SCHEDULINGLecture 05 THE WAY TO OPTIMIZE YOUR RESOURCES AND SAVE YOUR MONEY AND TIME1UEME4253 Project ManagementPERT and CPM Program Evaluation and Review Technique (PERT)U.S. Navy, Booz-Allen Hamilton, and Lockheed Aircraftprobabilistic activity durationsCritical Path Method (CPM)Dupont De Nemours Inc.deterministic activity durations2UEME4253 Project ManagementThe Language of PERT/CPMActivitya task or set of tasksuses resources and timeEventan identifiable state resulting from completion of one or more activitiesconsumes no resources or timepredecessor activities must be completed3UEME4253 Project ManagementThe Language of PERT/CPM continuedMilestonesidentifiable and noteworthy events that mark significant progressNetworka diagram of nodes (activities or events) and arrows (directional arcs) that illustrate the technological relationships of activitiesPatha series of connected activities between two events4UEME4253 Project ManagementThe Language of PERT/CPM concludedCritical Paththe set of activities on a path (from the projects start event to its finish event) that, if delayed, will delay the completion date of the projectCritical Timethe time required to complete all activities on the critical path5UEME4253 Project ManagementBuilding the NetworkThere are two ways of displaying a project networkActivities on Arrows (AOA) network in which the activities are shown as arrows and events as nodesActivities on Nodes (AON) network in which each task is shown as a node and the technological relationship is shown by the arrows6UEME4253 Project ManagementAON Network Stage 1

7UEME4253 Project ManagementAON Network - Stage 2

8UEME4253 Project Management AON Network - Complete

9UEME4253 Project ManagementAOA Network Stage 1

10UEME4253 Project ManagementAOA network Stage 2

11UEME4253 Project ManagementAOA Network - Complete

12UEME4253 Project ManagementAOA Network Showing The Use of a Dummy Task

13UEME4253 Project ManagementUEME4253 Project ManagementLecture 6-Project Activity Scheduling14Construct the Network (AOA Version)Dummy Activity

UEME4253 Project ManagementLecture 6-Project Activity Scheduling15Task e depends on task a and b and task d depends on task a, b and c.

UEME4253 Project ManagementLecture 6-Project Activity Scheduling16Task d depends on task a, task e depends on task a and b and task f depends on task b and c.

Information Contents in an AON NodeESEF

ES - Earliest start timeEF - Earliest finish time LS - Latest start timeLF - Latest finish time

LSLF ActivityActivity nameduration

17UEME4253 Project Management17Calculating Activity SlackLatest Start Time (LS) Earliest Start Time (ES) = SlackLatest Finish time (LF) Earliest Finish time (EF) = Slack18UEME4253 Project ManagementCalculating Probabilistic Activity TimesThe expected time (TE) is based on three time estimatespessimistic (B) Estimated Duration for the task that the actual finish time will be b or greater less than 1% of the time (almost never level)most likely (m)optimistic (A)

19UEME4253 Project ManagementThe Statistical Distribution of all Possible Times for an Activity

20UEME4253 Project ManagementActivity Expected Time and Variance

21UEME4253 Project Management6 is not weighted average but rather an assumption that the range of the distribution covers six standard deviation95 Percent LevelTask will be a or lower 5 percent of the timeTask will be b or greater 5 percent of the time

22UEME4253 Project Management90 Percent LevelTask will be a or lower 10 percent of the timeTask will be b or greater 10 percent of the time

23UEME4253 Project ManagementThe Probability of Completing the Project on Time

=NORMDIST(D,,,TRUE)Note: NORMDIST is a function within Excel when using the spreadsheet method24UEME4253 Project ManagementD = The desired project completion time

= the sum of the TE activities on the path being investigated

2 = the variance of the path being considered (the sum of the variance of the activities on the path)Selecting Risk and Finding D

NORMINV(probability,,,TRUE)Note: NORMMINV is a function within Excel when using the spreadsheet method25UEME4253 Project ManagementTraditional Statistics Versus SimulationsSimilarityboth procedures assume that task durations are statistically independent and the paths are independent Differencea simulation can circumvent the assumption of statistical independence by including the activity or path dependencies as part of the model26UEME4253 Project Management Gantt Chart of a Sample Project

27UEME4253 Project ManagementGantt Chart of Sample Project Showing Critical Path, Path Connections, Slack, ES, LS, EF, and LF

28UEME4253 Project ManagementExtensions to PERT/CPM Finish to Start (F to S)finish of Activity A to start of Activity B Start to Start (S to S)start of Activity A to start of Activity B Finish to Finish (F to F)finish of Activity A to finish of Activity BStart to Finish (S to F)start of Activity A to finish of Activity B29UEME4253 Project ManagementPrecedence Diagramming Conventions

30UEME4253 Project ManagementExampleUEME4253 Project Management31Microsoft Project Gantt ChartUEME4253 Project ManagementLecture 6-Project Activity Scheduling32

Microsoft Project AON NetworkUEME4253 Project ManagementLecture 6-Project Activity Scheduling33

ExampleUEME4253 Project ManagementLecture 6-Project Activity Scheduling34

ExampleUEME4253 Project ManagementLecture 6-Project Activity Scheduling35

Solving the Network (PERT)UEME4253 Project ManagementLecture 6-Project Activity Scheduling36

The AON NetworkUEME4253 Project ManagementLecture 6-Project Activity Scheduling37

Calculating Activity TimesUEME4253 Project ManagementLecture 6-Project Activity Scheduling38

The ResultsUEME4253 Project ManagementLecture 6-Project Activity Scheduling39

Critical Path and TimeUEME4253 Project ManagementLecture 6-Project Activity Scheduling40

Critical Path and Time ContinuedUEME4253 Project ManagementLecture 6-Project Activity Scheduling41

SlackUEME4253 Project ManagementLecture 6-Project Activity Scheduling42

Slack ValuesUEME4253 Project ManagementLecture 6-Project Activity Scheduling43

ExampleUEME4253 Project ManagementLecture 6-Project Activity Scheduling44

Example - PERTUEME4253 Project ManagementLecture 6-Project Activity Scheduling45

Find:The networkAll expected activity times, variances, and slacks.The critical path and expected completion time.The probability the project will be done in 23 days.The completion time corresponding to 95% probability.