Neighborhood Search Heuristic for 2-Machine Flowshop Scheduling Problem with Limited Waiting Times

The flowshop scheduling problem with limited waiting time constraints widely exists in the production process featured by high temperature and continuity. The constraints require that the waiting time of any job between two consecutive machines is not greater than a given upper bound. In this paper, the problem with two-machine settings and the objective of makespan is studied. First, a lower bound and some characters of minimum makespan are analyzed. Further, a solving idea is suggested by a transformation into an asymmetry TSP. Based on these characteristics and the solving idea, a neighborhood search algorithm embedding a modified Lin-Kernighan heuristic is presented for the problem. Numerical results demonstrated the effectiveness and efficiency of the algorithm.