论文标题
PPQ-Trajectory：大型轨迹存储库中查询的时空量化
PPQ-Trajectory: Spatio-temporal Quantization for Querying in Large Trajectory Repositories
论文作者
论文摘要
我们提出了PPQ-Trajectory，这是一种基于时空量化的解决方案，用于查询大型动态轨迹数据。 PPQ-trajectory包括一个通过分区预测量化器（PPQ），该量化器（PPQ）生成具有自相关和基于空间接近分区的错误结合的代码手册。该代码本已索引以在压缩轨迹上运行大致和精确的时空查询。 PPQ-trajectory包括一个坐标Quadtree编码代码簿，并支持精确查询。利用基于时间分区的增量索引来避免查询期间对轨迹的完全重建。提出了有关实际轨迹数据集的时空查询的广泛实验结果。 PPQ-Trajectory在几种性能指标方面表现出对替代方案的显着改善，包括当直接使用摘要来提供近似查询结果时，结果的准确性，当摘要用作汇总时，可以回答汇总时的空间偏差，以及用于构建摘要的时间时。还展示了有关摘要质量和压缩比的卓越结果。
We present PPQ-trajectory, a spatio-temporal quantization based solution for querying large dynamic trajectory data. PPQ-trajectory includes a partition-wise predictive quantizer (PPQ) that generates an error-bounded codebook with autocorrelation and spatial proximity-based partitions. The codebook is indexed to run approximate and exact spatio-temporal queries over compressed trajectories. PPQ-trajectory includes a coordinate quadtree coding for the codebook with support for exact queries. An incremental temporal partition-based index is utilised to avoid full reconstruction of trajectories during queries. An extensive set of experimental results for spatio-temporal queries on real trajectory datasets is presented. PPQ-trajectory shows significant improvements over the alternatives with respect to several performance measures, including the accuracy of results when the summary is used directly to provide approximate query results, the spatial deviation with which spatio-temporal path queries can be answered when the summary is used as an index, and the time taken to construct the summary. Superior results on the quality of the summary and the compression ratio are also demonstrated.
