Abstract: The work calendar and shift in realistic jobshop production environment split the effective work time of machine into a discrete state. In order to reduce the computational complexity of allocating the start and end time of a process, a time mapping algorithm (TMA) is proposed. The quick switch from discrete time spans to integral continuous intervals and from integral continuous intervals to discrete time spans is realized by the algorithm. Taking genetic algorithm (GA) scheduling as an example, the technology of how to integrate this algorithm with scheduling algorithms is also analyzed. The analysis illustrates that, compared with the scheduling algorithm without TMA, TMA can dramatically reduce the computational complexity of scheduling on allocating the start and end time of a process. By the algorithm, calculation time is reduced by 39.7% and the efficiency of scheduling is improved.

Key words: Jobshop scheduling, time mapping algorithm, work calendar