Research on Multi-Objective Distribution Vehicle Routing Problem for Spare Parts with Pick-Up and Delivery

In modern logistics and supply chain management, efficient spare parts distribution is crucial for maintaining equipment readiness and minimizing downtime. This paper presents an enhanced two-layer algorithm for solving the multi-objective vehicle routing problem (VRP) with unpaired pick-up and delivery demands, focusing on spare parts distribution. Building upon our previous work, this study introduces a detailed two-layer algorithm design, which includes an improved initial solution construction and offspring generation method within the NSGA-II framework. The algorithm aims to optimize transportation costs and customer satisfaction while addressing the complexities of unpaired demands. Extensive experiments demonstrate the effectiveness of the proposed method in achieving highquality solutions and computational efficiency. The paper also provides a detailed analysis of the algorithm's iterative process and convergence behavior, offering insights into the optimization dynamics.