In Lei, Lin Sixiang, Xie Binglei, Liu Lin
School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, China.
School of Architecture, Harbin Institute of Technology, Shenzhen 518055, China.
Math Biosci Eng. 2020 Nov 25;18(1):166-182. doi: 10.3934/mbe.2021009.
Vehicle drivers usually perceive a higher risk when driving on snow covered roads. The city cleaning efficiency would directly influence the risk and mitigation of wintertime events, especially for snow covered roads. Under the risk-informed approach background, more attention is paid to the capacitated arc routing problem (CARP) of urban snow plowing operations. Current algorithms mainly relies on the topology of road network without considering snow covered pavement's negative effect on road capacity and traffic flow. This paper proposes a vulnerability-based parallel heuristic algorithms applied for the CARP by implementing risk-informed approach. First, a method is proposed to set service priorities based on the vulnerability evaluation by considering the added cost of travel demands. Second, a sub-process path-scanning approach is developed to avoid redundant path scans. Then verification and comparison between this newly proposed constructive heuristic and existing algorithms of whole-process path-scanning and sequential processing are conducted. Results show that the sub-process path-scanning approach obviously costs less service completion time than the existing algorithms for solving the CARP. However, this improved algorithm would also cause an increase of deadhead time upon dispatch. The balance between service completion time and deadhead time for more routing problems would be discussed in the near future.
车辆驾驶员在积雪道路上行驶时通常会察觉到更高的风险。城市清洁效率将直接影响冬季事件的风险及缓解情况，尤其是对于积雪道路而言。在风险告知方法的背景下，城市除雪作业的容量弧路由问题（CARP）受到了更多关注。当前的算法主要依赖于道路网络的拓扑结构，而没有考虑积雪路面会对道路通行能力和交通流量产生负面影响。本文通过实施风险告知方法，提出了一种基于脆弱性的并行启发式算法，用于解决容量弧路由问题。首先，提出了一种通过考虑出行需求的附加成本，基于脆弱性评估来设置服务优先级的方法。其次，开发了一种子流程路径扫描方法，以避免冗余的路径扫描。然后，对这种新提出的构造性启发式算法与现有的全过程路径扫描和顺序处理算法进行了验证和比较。结果表明，对于解决容量弧路由问题，子流程路径扫描方法的服务完成时间明显比现有算法少。然而，这种改进算法在调度时也会导致空驶时间增加。未来将讨论在更多路由问题中服务完成时间和空驶时间之间的平衡。
