Active solution space and search on job‐shop scheduling problem

In this paper we propose a new searching method of Genetic Algorithm for the job-shop scheduling problem (JSP). The coding method represents job number in order to decide a priority to arrange a job in the Gantt chart (called the ordinal representation with a priority) in JSP, and an active schedule is created by using left shift. We define an active solution at first. It is a solution that allows the creation of an active schedule without using left shift, and the setting of a defined active solution space. Next, we propose an algorithm, Genetic Algorithm with active solution space search (GA-asol), which can create an active solution while solution is evaluated, in order to search the active solution space effectively. We applied it to some benchmark problems for comparison with other methods. The experimental results show good performance. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 154(4): 61–67, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20185