Job shop scheduling with dynamic fuzzy selection of dispatching rules

Although the academic contribution to job shop scheduling is abundant, its impact on practice has been minimal and so the preferred approach to job sh op scheduling in industry is the use of dispatching rules. A major criticis m of dispatching rules is that there is no single universal rule, and the e ffectiveness of a dispatching rule depends on the scheduling criterion and the prevailing conditions in the job shop. In this paper, the authors propo se a fuzzy scheduler that uses the prevailing conditions in the job shop to select dynamically the most appropriate dispatching rule from several cand idate rules. This method is applied to a formal testbed job shop problem an d a much larger problem that is representative of a real industrial problem . The results indicate that the fuzzy scheduler is effective.