Connectivity-oriented Vehicle Trajectory Data Query
面向路网连通关系的车辆轨迹数据查询技术研究

The advances in positioning and communication technologies make it possible to collect and transfer trajectories of moving vehicles. In addition to some basic applications such as navigation, traffic data can be extracted from vehicle trajectories, such as average moving velocity and travel time on a road segment in a given time period. The network and spatio-temporal characteristics of trajectories, however, make it difficult to evaluate queries applied to them. As a result, many studies have focused on developing index structures and methods for trajectory data. However, few of them have presented the corresponding data query language. In this paper, we discussed some issues related to trajectory data query language, including the definition of the connectivity-oriented data query language (CQL), the classification of CQL, and its implementation based on an index structure proposed by previous study. We further discussed a prototype for vehicle trajectory data query based on CQL in terms of its structure and implementation.