Study on the fuzzy scheduling problem of job shop based on genetic algorithm

Two kinds of models are formulated based on the studies on the job shop fuzzy scheduling problem of job shop. According to the model only with fuzzy processing time, the minimum fuzzy completion time is taken as the optimized object. As to the model with both fuzzy processing time and fuzzy due date, the maximum average agreement index is taken as the optimized object. The fuzzy processing time is denoted by the triangular fuzzy number and trapezoid fuzzy number. The fuzzy due date is denoted by the trapezoid fuzzy number and 6-point fuzzy number. Two fuzzy number comparison methods are given. The genetic algorithm is adopted to find the optimal scheduling sequence. Researches are made in aspects such as coding, decoding, crossover and mutation.