A note on "Single-machine scheduling problems with both deteriorating jobs and learning effects"

The main results in a recent paper [1] (J.-B. Wang, D. Wang, G.-D. Zhang, Single-machine scheduling problems with both deteriorating jobs and learning effects, Appl. Math. Model. 34 (2010) 2831-2839) are incorrect because job processing times are variable due to both deteriorating jobs and learning effects, which is not taken into account by the authors. In this note, we show by counter-examples that some published results are incorrect.Department of Industrial and Systems Engineerin