A Two-Level Production Control Model with Target Amount Rescheduling

This paper deals with the problem of two-level production control with disturbances. A production system is considered with several machines on the lower level and a section on the upper one. Each machine produces a given target amount by a given due date (common to all machines). Each machine has several possible speeds, which are subject to disturbances. On the machine level, at the routine control point, decision-making centres on introducing the proper speed and determining the next control point. It is assumed that all the target amounts are transferable; i.e. a part of each target amount can be processed by any other machine. In a case when it is realized, for a certain machine, that the target cannot be completed on time, the section reschedules the remaining target amounts among the machines. New target amounts are determined for the machines so that the overall target can be accomplished on time. A stochastic optimization formulation is presented, followed by a heuristic solution and simulation results.