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Production and Operations Management Systems. Chapter 7: Project Management Sushil K. Gupta Martin K. Starr 2014. After reading this chapter, you should be able to (continued):. Draw project network diagrams. Find critical paths and project durations.
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Production and Operations Management Systems Chapter 7: Project Management Sushil K. Gupta Martin K. Starr 2014
After reading this chapter, you should be able to (continued): • Draw project network diagrams. • Find critical paths and project durations. • Calculate early start, early finish, late start and late finish times of activities. • Explain how to use forward-pass calculations to determine the shortest feasible time for project completion. • Explain how to use backward-pass calculations to determine which project activities are on the critical path.
After reading this chapter, you should be able to (continued): • Describe what slack means; explain how to derive it. • Crash activities (including multiple paths) to reduce project duration; perform time-cost tradeoff analysis. • Analyze probabilistic projects; explain when deterministic and probabilistic estimates for activity times apply. • Show how to use optimistic and pessimistic activity time estimates to obtain a variance measure for activity times. • Identify implications of limited resources.
Introduction Projectsconsist ofasetofgoal-orientedactivitiesthatendwhen thegoalisachieved. Suchundertakingsare time-basedendeavors and haveafiniteplanninghorizon. Projects arespecialworkconfigurations designedtoaccomplishsingularornearlysingulargoals. Examples include: puttingon one play,writingnew software, constructingabuilding, launching anewproduct,redesigning an established traditional hotel, and developinganewservice etc. In this presentation we discuss management of projects.
Classification of Projects Projectscanbeclassified according to the following criteria: • Degreeofsimplicity to change things. • Degreeofcomplexity reflecting the number of people, teams, components and activities. • Frequency ofrepetition. • Number of newactivitiesinvolved. . .
Managing Projects Competent projectmanagementmethodskeeptrackofwhat is required at start up, what hasbeendone as it progressesandwhatstill needstobedone. Goodprojectmethods pointtoactivitiesthatarecriticalforcompletion. Project managers expediteimportant activitiesthatseemtobeslipping. These points arepartof thefiveprojectlifecyclestages (below): • Begin by describinggoals which requiresdevelopingandspecifying thedesiredproject outcomes.
Managing Projects (continued) • On prior page • Planning the project requires specifying (in detail) the activities that are essential to accomplish the goals. It involves planning the management of the project includingthetimingoftheactivities. • Carrying out the project requires doing the activities as scheduled. • Completing theprojectcanmeandisbandingworkgroupsandclosingdownthe project-management team. • The use of continuous projectteamsisanincreasinglyattractiveoption.
Project Management Origins Starting about 1957, two similar approaches to large-scale project network planning and tracking were begun at separate locations and for different reasons. These were: • PERT—program evaluation review technique • CPM—critical path method PERT was developed by the U.S. Navy Special Projects Office in conjunction with Booz Allen Hamilton for the Polaris submarine launched missile project. There were about 100,000 activities divided amongst thousands of suppliers.
Project Management Origins (continued) CPM was a similar method developed by DuPont and Remington Rand, which later became Unisys. It was used to design and coordinate chemical plant operations. The essential difference between PERT and CPM is in specifying the times for performing various activities. PERT was used for projects where the activity times were not certain because project managers were unfamiliar with the activities. On the other hand the projects and activities were familiar to the project managers in the case of CPM. These days the distinction between PERT and CPM seems to be disappearing and together these are called PERT/CPM or simply network techniques. These two methods share the notion of a critical path as discussed later in the chapter.
Project Network The following steps are required to utilize these network models. Make a list of all activities that are required to complete the project. Establish the precedence relationships among activities and document the rationale for these relationships. Estimate the time to perform each task or activity using one of the following two options. • Option 1: deterministic estimates for activity times. • Option 2: probabilistic estimates for activity times. Draw the precedence diagram (of project activities). Develop a project schedule.
Project Management Example Activity on Node (AON) Diagram
Resource Management Resource management switchesextraresourcesfrom placeswhere theyarenot essentialto placeswheretheycouldbeusedimmediately, that is, balanceresourceassignmentsacrossactivitiesovertime. Resource management has two functions – resource leveling and resource scheduling. In resource leveling the goal is to minimize the fluctuations in resources required from one period to another over the life of the project. In resource scheduling it is assumed that there is an upper limit on the resources available and all activities are to be scheduled within the resource constraints.
