A rule-based approach for fuzzy overhaul scheduling

Decisions on an overhaul schedule are often required by a dredging company in Shanghai because the fleet of dredges require regularly maintenance due to their heavy duty work. The decision on an overhaul schedule attempts to determine how the overhaul project completion time can be minimized. However, there are a number of constraints where jobs in the overhaul project have precedence relations, and human resources are limited. In addition, job duration times are fuzzy, and jobs may have several performance modes. Because of the complexity of computation, any exact approaches may be not viable. This paper proposes a fuzzy rule-based heuristic approach using the information available in the system. The approach developed here provides a fast scheduling result in such a complex decision, aiding readjustment of production in time. In addition, the approach also helps the company to save significant costs annually in decisions on overhaul projects.