PRODUCTION SCHEDULING IN PREEMPTIVE AND SIMULTANEOUS PROCESSING

The paper explores production scheduling problems in which jobs with deadlines are processed preemptively and/or simultaneously on identical machines. Based on the concepts of reservations and surpluses, it is checked whether a given set of n jobs is feasible. The nonsimultaneous processing problem of minimizing the sum of completion times on identical machines is discussed. For the simultaneous processing problem of minimizing the total splittings, an on-line approximation is presented and an integer programming is formulated. The problem of minimizing the costs of both splittings and tardiness is also formulated as an integer programming problem. The results of testing the approximation algorithms are satisfactory.