A MATHEMATICAL MODEL OF SUPPLY SUPPORT FOR SPACE OPERATIONS

The Memorandum develops a methodology to evaluate various aspects of logistics supply support of space bases. It is assumed that there exists at the space base a schedule of operations which reflects the day-to-day living, build-up, and scientific experimental activities that are to be carried on. These activities, in turn, set a series of demands or requirements for products over a time spectrum. The supply system must deliver products so as to meet the amounts and times of the product requirements. Each product or module has an earliest and latest time by which it must be delivered. The model plans a series of trips, the dates at which each is to be sent, and the composition of the cargoes on each trip which satisfy the series of requirements over a time spectrum imposed by the activities at the space base. The series of trips are an expression of an efficient plan which simultaneously considers demands for different products at different future times and observes the various constraints of the system (e.g., cargo capacity of spaceships). The scheduling model can be used in two different modes: as part of a control system for an actual space base, or as a planning tool to aid in the design of a space base and the formulation of operations schedules. Rept. on Proj. RAND.