Popis: |
A new concept of multi-shop (M ) is put forward which contains all basic shops including open shop (O), job shop (J ), flow shop (F ) and hybrid flow shop (H ) so that these basic shop can be scheduled together. Several algorithms including ant colony optimization (ACO), most work remaining (MWR), least work remaining (LWR), longest processing time (LPT) and shortest processing time (SPT) are used for scheduling the M. Numerical experiments of the M adopting data of some car and reC series benchmark instances are tested. The results show that the ACO algorithm has better performance for scheduling the M than the other algorithms, if minimizing the makespan ( C m*ax) is taken as the objective function. As a comparison, the separate shops contained in the M are also scheduled by the ACO algorithm for the same objective function, when the completing time of the jobs in the previous shop is taken as the ready time of these jobs in the following shop. The results show that the M has the advantage of shortening the makespan upon separate shops. |