Abstract

In studies on scheduling problems, generally setup times and removal times of jobs have been neglected or by including those into processing times solution approaches have been developed. However, as setup times and removal times may be too important to be neglected in some production systems, it may also be necessary to consider processing times independent from setup times and removal times. Since, in general jobs are done according to automatic machine processes in production systems processing times do not differ according to process sequence. But, since human factor becomes influential when setup times and removal times are taken into consideration, setup times will be decreasing by repeating setup processes frequently. This fact is defined with learning effect in scheduling literature. It is shown in several examples that the optimal schedule of the problem may be different from that of the classical one. Nevertheless, the makespan and the total flow time minimization problems remain polynomial solvable.