PROJECT SCHEDULING WITH CONTINUOUSLY-DIVISIBLE, DOUBLY CONSTRAINED RESOURCES

This study deals with a class of project scheduling problems concerning the allocation of continuously divisible resources under conditions in which both total usage at every moment and total consumption over the period of project duration are constrained. Typical examples of such resources, called doubly constrained, are money or energy, when the constraint on power or the rate of expenditure cannot be ignored as neither, of course, can the constraint resource consumption. Also manpower must ofen be considered as a doubly constrained resource. Mathematical models of project activities in which performing speeds are continuous functions of resource amounts are considered. The objective is a schedule which minimizes project duration. The problems considered are generalizations of both the classical project scheduling problem and the time-cost trade-off problem.