Mutating Evolution Algorithm for Locomotive Diagram with Double Shoulders-Circuit Locomotive Routing by Unfixed Traction Mode

A mathematical model for double shoulders-circuit locomotive routing by unfixed traction mode has been presented whose objective is to minimize the total time for locomotives staying in districts and an optimized schedule has been obtained with a mutating evolution algorithm. The algorithm carries on the varying-degree mutation according to the fitness of the individual and uses the heuristic mutation. The stochastic mutation can make the eminent schemas heredity to the filial generation which, from the chromosome of the excellent individuals, maintains the multiplicity of the filial generation. Thereby the algorithm can enhance the optimized capability and the convergence rate. The proposed method has been tested over an actual problem of train diagram. The results show that the total time of locomotives staying in districts and the required number of locomotives are reduced by about 23.8% and 9.8 %, respectively, compared with the genetic algorithm.