PLANNING FOR IDLE TIME - A RATIONALE FOR UNDERUTILIZATION OF CAPACITY

This paper presents a mixed integer linear programming formulation which optimizes the sequence of jobs through a single facility and which places the correct amount of idle time between jobs to minimize the sum of earliness and tardiness penalties. Although this formulation reaches an optimal solution is every instance, the computation time required was found to grow in an exponential manner as the number of jobs considered increased. Given the cost of computing at present, there appears to be a need for more computationally efficient heuristics to solve this problem.