SINGLE MACHINE SCHEDULING WITH GENERAL LEARNING FUNCTIONS: OPTIMAL SOLUTIONS

In traditional scheduling problems, most literature assumes that the processing time of a job is fixed. however, there are many situations where the processing time of a job depends on the starting time or the position of the job in a sequence. in such situations, the actual processing time of a job may be less than its normal processing time if it is scheduled later. this phenomenon is known as the ‘‘learning effect’’. in this study, we introduce general learning functions into a single-machine scheduling problems. we consider the following objective functions: (i) sum of weighted completion times, (ii) maximum lateness (iii) number of tardy jobs (iv) number of weighted tardy jobs. non-linear programming models are developed for solving these problems..