Some observations and extensions of the optimal TWK-power due-date determination and sequencing problem

This paper considers the same problem as studied previously by Cheng which is concerned with the optimal determination of TWK-power due-dates and sequencing of n jobs on a single machine. A detailed analysis of the cost function used in Cheng's model is presented from which we note that under suitable assumptions a very simple way to find the optimal solution is available. An extension of the original due-date sequencing optimization problem is discussed and the necessary and sufficient optimality conditions for the extended problem are derived.