A bi-objective mathematical model for two-dimensional loading time-dependent vehicle routing problem
研究城市配送中矩形货物装载与时间依赖路径的双目标优化问题，提出精英非支配排序局部搜索算法，在小规模问题中与精确解对比，中规模问题中与NSGA-II和SPEA2对比，验证了算法性能。
This paper introduces two-dimensional loading time-dependent vehicle routing problem and proposes a bi-objective mathematical model. This problem assesses the process of distributing the rectangular-shaped demanded items over an urban environment; it does not, however, allow items to be loaded on top of each other. In addition to the above assumptions, the presented model also satisfies the first-in-first-out property in the time-dependent vehicle routing problem. Given the NP-hard nature of the problem, a method called elitist non-dominated sorting local search is developed to obtain its solutions. To evaluate the performance of the proposed algorithm, the solutions of this algorithm for small-scale problem instances are compared with the results of an exact method. For the medium-scale problem instances, results of NSGA-II and SPEA2 are used as the basis of comparison. The computational results demonstrate the good performance of the proposed method.