Hybrid harmony search-based flexible job shop scheduling method

Abstract

The invention relates to a hybrid harmony search-based flexible job shop scheduling method. The hybrid harmony search-based flexible job shop scheduling method comprises the following steps that: 1) solution vectors of FJSS (flexible job shop scheduling) to be solved are defined; 2) solution vectors in harmony search are converted into codes of feasible solutions of the FJSS; 3) a harmony search algorithm framework is adopted to perform harmony search, at firstly, a plurality of solution vectors are initialized randomly, and the maximum number of iterations is set, and at each iteration, a new solution vector is generated through harmony search; 4) the new solution vectors are converted into corresponding scheduling solutions, and the scheduling solutions are expressed by disjunctive graphs; 5) after the new scheduling solutions are generated, public key operation-based local search which is put forwards is executed with a certain probability based on the disjunctive graphs, and the disjunctive graphs are adjusted through the local search, so that improved scheduling solutions can be obtained, and then, the improved scheduling solutions are converted into solution vectors, and the obtained solution vectors are refined, and the refined solution vectors are adopted to replace the solution vectors before the local search, and the next iteration of harmony search is executed further; and 6) after the execution of the search is completed, an optimal solution vector is decoded, so that a final scheduling solution of the FJSS can be obtained.

Description

technical field [0001] The invention belongs to the technical field of computer application and production scheduling, and relates to the key scheduling problem involved in industrial production such as semiconductor production, automobile assembly, and textiles, that is, the flexible job shop scheduling problem (FlexibleJobShopScheduling, FJSS). Acoustic search for 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 v...

AI Technical Summary

Problems solved by technology

[0019] However, none of the harmony search algorithms described above can be directly applied to solve the FJSS problem, because the operator operations of the harmony search are all based on real number coding. The original purpose of the algorithm is to solve continuous optimization problems, and FJSS is a For the problem of discrete optimization, harmony search often has the problem that it is easy to fall into local optimum in the search process

Images