A solution approach for parallel machine scheduling problem in Tai-Turkish Aerospace Industries Inc.

In this project, a parallel machine scheduling problem with sequence dependent setup times in the CNC profile and part manufacturing center of Turkish Aerospace Industries, Inc. has been considered. Firstly, a mixed integer linear programming model is developed for the problem. Since the problem is an NP-hard problem and the job groups to be scheduled consist of 50 or more jobs, it is not possible to obtain optimal solution with well known solvers such as CPLEX for the problem. Therefore, in order to obtain optimal or near optimal schedules in an acceptable time period, a heuristic algorithm based on simulated annealing (SA) algorithm is developed. The performance of the developed algorithm is comparatively investigated using multi start local search algorithm in terms of solution quality. While both algorithms have same performance for small-size problems, SA algorithm exhibits better performance than multi start local search algorithm for large-size problems. Moreover, an interface integrated with the developed heuristic algorithm is designed. By means of the interface, schedules for the jobs drawn from the database of firm for each station are obtained.