有软时窗多车场开放式车辆路径及其禁忌搜索

有软时窗约束多车场开放式车辆路径问题是在基本的车辆路径问题上增加了时间窗约束和多车场作业的一种变化形式,是一个典型的NP-难问题。建立了问题模型,运用改进的禁忌搜索算法测试了算例。快速获得的高质量解验证了模型的正确性和算法性能的优良性。

一类多出发点多旅行商问题规划算法

提出了一种基于K-means聚类算法的多出发点多旅行商问题求解的新方法.算法定义了节点的吸引度,通过节点吸引度矩阵进行子环游节点集的归类,并对各子环游应用单旅行商启发式算法进行求解.实例表明,此规划算法能很好地求解多出发点多旅行商问题.

Enhanced solution representations for vehicle routing problems with split deliveries

In this study,we investigate a forest-based solution representation for split delivery vehicle routing problems(SDVRPs),which have several practical applications and are among the most difficult vehicle routing problems.The new solution representation fully reflects the nature of split delivery,and can help reduce the search space when used in heuristic algorithms.Based on the forest structure,we devise three neighborhood search operators.To highlight the effectiveness of this solution representation,we integrate these operators into a standard tabu search framework.We conduct extensive experiments on three main SDVRPs addressed in the literature:The basic SDVRP,the multidepot SDVRP,and the SDVRP with time windows.The experimental results show that the new forest-based solution representation is particularly effective in designing and implementing neighborhood operators,and that our new approach outperforms state-of-the-art algorithms on standard datasets.

一种多出发点多旅行商问题到旅行商问题的转换

本文通过复制出发点和引入虚点,将一种多出发点多旅行商问题转换成标准旅行商问题,从而可用标准旅行商问题的算法求解多出发点多旅行商问题。