An evaluation method and system for an intermediate scheduling scheme of a job shop

Abstract

The invention discloses an evaluation method and system for an intermediate scheduling scheme of a job shop, and belongs to the technical field related to shop scheduling. According to the invention, only the values of 'head length + tail length + process processing time ' of two specific processes in the neighborhood solution are calculated, so that the evaluation efficiency is improved; The method comprises the following steps: taking a larger value in parameter summation results of specific procedures as a preliminary evaluation result, and dividing the preliminary evaluation result into two classes: comparing the preliminary evaluation result with completion time in an original solution, taking the preliminary evaluation result greater than or equal to the completion time of the original solution as a first class, and taking the preliminary evaluation result as a final evaluation result of the neighborhood solution; and taking the initial evaluation result smaller than the original solution completion time as a second class, and reducing the influence of other procedures without changing the processing sequence on the critical path on the evaluation result by introducing an error correction parameter, so that the initial evaluation result is further corrected. Through the operation, the effects of improving the evaluation accuracy and reducing the evaluation error are finally achieved.

Description

technical field [0001] The invention belongs to the technical field related to workshop scheduling, and more specifically relates to a method and system for evaluating an intermediate scheduling scheme of a job workshop. Background technique [0002] The workshop scheduling problem refers to improving the production efficiency of the workshop and reducing the production cost by determining the processing sequence of the workpiece on the machine. The job shop scheduling problem (job-shop scheduling problem, JSP) is a classic shop scheduling problem, which can be simply described as having n workpieces, each of which has m processes, and these processes need to be performed on m different machines. For processing, different workpieces flow through the machines in different sequences. What needs to be decided is the processing sequence of the workpieces on each machine, and finally makes some indicators optimal. [0003] JSP is an NP (non-deterministic polynomial, non-determi...

AI Technical Summary

Problems solved by technology

The advantage of this method is that it can evaluate the neighborhood solution very quickly, but it has the disadvantage that the value obtained after evaluation may not be accurate

In order to balance the solution quality and solution efficiency, the approximate evaluation method is usually used to evaluate the neighborhood solution in the existing research, among which Balas et al. (Balas E, Vazacopoulos A. Guided local search with shifting bottleneck for job shop scheduling[J].Management science,1998,44(2):262-275.) The evaluation method proposed is the best and most commonly used evaluation method in the existing research, and its comprehensive performance is the best, but there are still a lot of unnecessary Calculation process, and the results after evaluation are not accurate enough, etc.

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