Heuristic Approach to Nonstandard Form Assignment Problems

Many problems of the practicing operations analyst do not fit the standard forms of analytic OR procedures and do not lend themselves to precise optimization methods. The voracious appetite of the computer demands numerical algorithms in order to give answers. Very often an optimum is not absolutely essential to management, as long as the answer is efficient or superior to guesswork. So heuristic approaches are adapted to the problem. This paper presents a heuristic approach to a nonstandard, practical assignment problem. It concerns a problem that the analyst had to solve “in the field” at Cape Canaveral (now Cape Kennedy) wherein 74 telemetry channels for 19 missiles had to be assigned to 28 available frequency bands. A conflict for a channel occurs if (a) time for use of the range by the missile channels is demanded and (b) another channel on another missile has the same frequency assignment and also wishes the same time. A conflict means one or more missiles must be denied time on the range, which causes costly delay. It is desirable to assign channels to frequencies (which is done at the time the missile is designed) so as to minimize the total expected amount of conflict (or cost of conflict). This paper shows a general, heuristic (not-necessarily optimum) procedure for handling typical, nonstandard assignment problems and gives details of the Cape Kennedy application. This is an example of what can happen “in the field” when standard mathematical forms are not available.