The project coordinator's problem

A project coordinator has a set of activities with known durations and values which are available for scheduling within a given horizon. There may be both precedence and corequisite restrictions (two activities are corequisites if scheduling one implies the other must be scheduled). The project coordinator's problem is to select the activities to be scheduled, and their start times, so as to maximize the net value of the project when there is no penalty for failing to schedule an activity. An efficient solution procedure is developed and illustrated and several generalizations are discussed.