In this chapter the scheduling aspect of project implementation was addressed. Following a description of the benefits of using a network for planning and controlling a project, the PERT/CPM approach was described. Next. Gantt charts were described and their relation to the PERT/CPM diagram was illustrated. Finally, precedence diagramming, GERT, and a few other extensions were discussed.
Specific points covered in the chapter were these:
• Scheduling is particularly important to projects because of complex coordination problems.
• The network approach to scheduling offers a number of specific advantages of special value for projects.
• Critical project tasks typically constitute fewer than 10 percent of all the project tasks.
• Although research indicates technological performance is not significantly affected by the use of PERT/CPM, there did seem to be a significantly lower probability of cost and schedule overruns.
Network techniques can adopt either an activ-ity-on-node or activity-on-arc framework without significantly altering the analysis. Networks are usually constructed from left to right, indicating activity precedence and event times as the network is constructed. Through use of the network, critical activities and events are identified, early and late activity start times are found, available slacks for each activity are determined, and probabilities of project completion by various times are calculated.
Gantt charts, a monitoring technique, are closely related to network diagrams, but are more easily understood and provide a clearer picture of the current state of the project. However, while offering some advantages, they also have some drawbacks, such as not k clearly indicating task precedence and dependencies.
GERT is one of the more common extensions of PERT/CPM and allows: Probabilistic branching from nodes, Various probability distributions for the activity times, Looping in the network.
Representation of project elements other than time, such as cost or reliability.
In the next chapter we investigate the scheduling problem further when multiple projects require a set of common resources to be shared. Again, a number of techniques are useful for resource allocation and activity expediting under such circumstances.
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What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.