个人出行轨迹中轨道交通段GPS信号缺失修补算法

基于GPS的个人出行轨迹在城市路网环境中信号丢失较为严重。针对城市轨道交通段的GPS信号缺失问题提出了相应解决办法。研究分析了出行者在换乘节点的一般时空行为以及GPS轨迹的形态特征,给出在特定情况下模型中最优路径的界定,以此制定出交通路段选取规则;在逻辑设计上结合地理信息数据库的语义信息和轨道交通网的拓扑结构,开发了基于广度优先原则的轨道交通段GPS信号的修补算法。此外,研究结合使用Baidu Map API开发了修补效果的在线可视化平台,以上海市内20组GPS个人出行数据进行了实例分析。结果表明,算法的修补效果良好,设计思路合理,且计算和修补时耗线性单增,具有一定的实用价值。

An Algorithm for Repairing Missing Trajectories of GPS Data in Personal Light-rail Travel

Modern transport information services rely heavily on GPS-based personal travel data,which is unfortunately haunted by missing data problems.This paper focuses on developing solutions to the GPS signal loss problem due to light rail travel within the city.The traveler＇s spatiotemporal behavior at the transfer nodes between walking and light-rail and the morphology of trajectories were analyzed,and a ＂breadth-first＂ repairing algorithm was proposed and developed by integrating the topological structure of the light rail network and semantic information into the model.An online mapping system,Baidu Map API,was used for visualizing the original GPS data and repairing results.A case study in Shanghai indicates that the algorithm produces good repairing effects in a reasonably efficient manner.