关键词: 柔性车间调度, 工序顺序柔性, 表达式树, 遗传算法

Abstract: A description model based on the expression tree was proposed to solve the Job Shop Scheduling Problem (JSP) with process sequence flexibility,and a method for the generation of random process sequences was presented.A mathematical model of the problem and its solution procedure of the Genetic Algorithm (GA) were established with makespan as the optimization objective.Based on the presented method,the encoding and decoding schema was designed,and genetic operators were selected according to the code.A brevity chromosome code consists of 0 and 1 and representsed any feasible solution.Computational experiments were conducted on benchmarks of different scales and flexibility indexes.The performance of the expression tree model was proved by comparison with the model without process sequence,random sequence model,and flexible segments model.

Key words: flexible job shop scheduling, process sequence flexibility, expression tree, genetic algorithms