A revision of some single-machine and m-machine flowshop scheduling problems with learning considerations (vol 179, pg 3885, 2009)

Lee and Wu [3] introduce a scheduling model in which the job processing times are affected by both position-based and sum-of-processing-time-based learning effects simultaneously. We demonstrate by a counter-example that their main results are incorrect. We provide a revised model of the general learning effect and show that some single-machine scheduling problems are polynomially solvable under the revised model. We also show that some special cases of flowshop scheduling can be solved in polynomial time under the revised model. (C) 2011 Elsevier Inc. All rights reserved.