An improved mathematical model and a hybrid metaheuristic for truck scheduling in cross-dock problems

• A mathematical model, more effective than the available one, is presented.
• A novel algorithm, outperforming two state-of-the-art metaheuristics, is proposed.
• Using numerical experiments, the effectiveness of the model and algorithm is evaluated.

Recently, several papers study the problem of scheduling inbound and outbound trucks in cross-dock systems. There is only one attempt to mathematically model the problem. Unfortunately this model is ineffective due to its size complexity. Moreover, although different metaheuristics are proposed in the literature, they are not tailored-made for this problem. In this paper, a new mixed integer programming model is formulated for the problem. Using commercial optimization solvers, the performance of the proposed model is compared with the available model to solve small instances. To solve larger instances, a particle swarm optimization hybridized with a simulated annealing is proposed. Using Taguchi method, the proposed algorithm is tuned. Then, it is evaluated against two other available metaheuristics (genetic algorithm and electromagnetism-like metaheuristic) in the literature.