Fuzzy distributed two-stage hybrid flow shop scheduling problem with setup time: collaborative variable search

Distributed scheduling has attracted much attention in multiple factories. However, uncertainties are often neglected in the previous works and this neglecting may result in the low value of the obtained schedule. In this study, fuzzy distributed scheduling is addressed in two-stage hybrid flow shop with sequence-dependent setup times(SDST) which is a frequently studied constraint in single factory and seldom handled in multiple factories. A collaborative variable search (CVS) is proposed to optimize total agreement index and fuzzy makespan simultaneously. Seven neighborhood structures and two global search operators are used in two cooperated variable search parts to generate high quality solutions. Experiments are conducted and the computational results reveal that CVS has promising advantages on the considered fuzzy distributed scheduling problem.