EAAI Journal 2026 Journal Article
An enhanced memetic algorithm for a novel two-stage flow shop scheduling problem with group processing features
- Shuaipeng Yuan
- Bailin Wang
- Yihan Pei
- Tieke Li
This study addresses a novel two-stage flow shop scheduling problem motivated by hot rolling production management in modern steel manufacturing. The first stage is modeled as a simultaneous processing machine subject to a first-in-first-out rule and capacity constraints, while the second stage features a group processing mechanism. This problem fundamentally differs from conventional batch scheduling and group scheduling, and it requires simultaneously determining the job sequence and the processing manner of adjacent jobs on the second machine. To tackle this NP-hard problem, a mixed-integer linear programming model is formulated to minimize the makespan, and three fundamental properties are analytically derived. Leveraging these insights, an enhanced memetic algorithm is proposed, incorporating a greedy rule-based decoding strategy, a heuristic-driven initialization, a global search framework with five specialized neighborhood operators, and a local search strategy comprising four tailored operators. A reset mechanism is incorporated to avoid premature convergence. Extensive experiments demonstrate that the proposed memetic algorithm outperforms three other meta-heuristics and an industry-based heuristic, confirming its effectiveness for intelligent scheduling in practical settings.