Optimization Solution to Lot Sizing and Scheduling Problem in Hybrid Flow-Shop

Considering the size of lot can directly affect the performance, when we try to solve scheduling problem in a hybrid flow-shop environment, in this paper we propose a blend search strategy and a new way to calculate the completion of produce. This search strategy combine genetic algorithm with simulated annealing algorithm, and the more important we employ the merger operation to reduce resolution space, the re-heat technology to prevent the best solution missing and optimal-reserve operation to staticize it. in this way, the size of lot and schedule can be optimal in the same time. and the new way to calculate the completion time not only gives a more accurate execution time of manufacture system as the performance of optimization solution, but also gives the detail in each workshop and each machine, which show production planning of each machine in each workshop and each machine. It can be used by production people to follow and compare with the real situation in order to find the problem in the process and adjust some parameters of the workshop which can be used for the next times.