Harmony Search Algorithms for Bi-criteria No-idle permutation Flow Shop Scheduling Problem

Three hybrid harmony search (HS) algorithms are proposed for solving Bi-criteria No-idle permutation Flow Shop Scheduling Problem in this paper. Two objectives, i.e. the maximum completion time (makespan) and the total flow time (TFT), are considered simultaneously. The proposed algorithms firstly convert continuous harmony vectors into job permutations according to the largest position value (LPV) rule. Then the algorithms use the NEH algorithm to initialize one harmony and the others are initialized randomly. Lastly, a local search method is used in the proposed algorithms to enhance the exploitation capability. The extensive computational experiments demonstrate the high effectiveness and searching ability of the hybrid harmony algorithms especially the hybrid Globalbest harmony search (hGHS) algorithm.