Optimization for Due-Date Assignment Single-Machine Scheduling under Group Technology

In this paper, the single-machine scheduling problem is studied by simultaneously considering due-date assignment and group technology (GT). The objective is to determine the optimal sequence of groups and jobs within groups and optimal due-date assignment to minimize the weighted sum of the absolute value in lateness and due-date assignment cost, where the weights are position dependent. For the common (CON) due-date assignment, slack (SLK) due-date assignment, and different (DIF) due-date assignment, an O n log n time algorithm is proposed, respectively, to solve the problem, where n is the number of jobs.

Scheduling with position-dependent weights, due-date assignment and past-sequence-dependent setup times

In this study, we consider single-machine scheduling problems with past-sequence-dependent (denoted by psd) setup times in which the setup times of jobs are proportional to the length of already processed jobs. Under common (CON) and slack (SLK) due-date assignment methods, we prove that the weighted sum of earliness, tardiness and due-date minimization remains polynomially solvable. We also give some extensions for the scheduling problems with psd setup times.