Multitasking scheduling problems with a common due-window

We study multitasking scheduling and due-window assignment problems in a single machine, which can be found various application domains. In environment, unfinished job always interrupts in-processing job. common due window assignment, the aim is to find optimal minimise value of earliness tardiness penalty. this paper, we two problems, where objective first problem earliness, tardiness, starting time, size costs, second minmax due-date with completion time penalty, then obtain some analytical properties provide polynomial solutions. Finally, experimental results show that proposed methods are effective.