Research on parallel rescheduling for hybrid blocking flow shops based on an improved iterative greedy algorithm

Abstract

This paper addresses the production scheduling problem in a ship panel block workshop subject to processing time disturbances, with the aim of optimizing the workshop’s production duration under the influence of such disturbances. First, the production process of the panel block workshop is introduced. Fuzzy triangular numbers are employed to describe the uncertainty in processing times during the production process, and a fuzzy workshop scheduling model is constructed. Next, an improved iterative greedy algorithm is designed, combining a dynamic break-and-rebuild strategy with variable neighborhood search to enhance the algorithm’s global search capabilities and local optimization capabilities. Corresponding rescheduling strategies are proposed for two types of disturbance events: workpiece insertion and machine failure. The effectiveness and practicality of the proposed method in a dynamic environment are verified using actual production cases from a shipyard.