Integrated search method for large-scale flexible job shop scheduling

Abstract

The invention relates to an integrated search method for large-scale flexible job shop scheduling. The integrated search method comprises the following steps that: 1) a solution vector of FJSS (flexible job shop scheduling) to be solved is defined; 2) a solution vector in hybrid harmony search is converted into the codes of a feasible solution of the FJSS; 3) a hybrid harmony search algorithm is adopted to perform harmony search; 4) the solution vector of the harmony search is converted into the scheduling solution of an FJSP problems, and corresponding neighborhoods are designed based on the scheduling solution, and local search is performed through using the designed neighborhoods, and an improved scheduling solution which is obtained through the local search is converted into a solution vector, and the solution vector is utilized to replace the solution vector before the local search, and the search process of the harmony search is continued, so that an optimal solution can be obtained; and 5) the optimal solution which is found based on the hybrid harmony search algorithm is adopted as the initial solution of a large-scale search algorithm, and the large-scale search algorithm is adopted to continue search until a termination condition is satisfied, and scheduling of which the solution is completion time can be obtained.

Description

technical field [0001] The invention relates to the technical field of computer application and production scheduling, in particular to an integrated search method for large-scale flexible job shop scheduling. Background technique [0002] In music performance, musicians rely on their own memory to repeatedly adjust the pitch of each instrument in the band to finally reach a beautiful harmony state. Inspired by this phenomenon, Korean scholar GeemZW and others proposed a harmony search algorithm. The musical instrument i (i=1,2,...,n) is compared to the i-th variable in the optimization problem, the pitch of each musical instrument is analogous to the value of each variable, and the harmony R of the pitch of each musical instrument j (j=1,2,...,m) is analogous to the jth set of solution vectors of the optimization problem, and the evaluation effect of music is analogous to the objective function. The basic harmony search algorithm generates m sets of initial solutions (harm...

AI Technical Summary

Problems solved by technology

[0020] HHS (Hybrid Harmony Search, HHS Hybrid Harmony Search) is a method based on evolutionary computing. Its advantage is that it can quickly generate high-quality solutions. However, when solving large-scale problems, the ability to explore and develop is insufficient. If the number of iterations is further increased, the obtained results will not be further improved; LNS is a method based on constraint programming. Its advantage is that it has a strong search and development (climbing) ability, but its disadvantage is that the search performance depends on the initial solution, and the search and development ability Decreases sharply with increasing problem size

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