移动轨迹的尺度特征

移动轨迹是移动对象在地理空间环境中移动而留下的痕迹。移动轨迹数据是一类特殊的地理时空数据，它具有时间尺度、空间尺度和语义尺度特征。本文首先分析了轨迹数据的空间尺度特征与时间尺度特征，建立了轨迹空间尺度与时间尺度转换关系式；然后论述了轨迹的语义内涵和语义尺度特征，将轨迹语义分为移动对象语义、地理空间环境语义、采集设备语义、移动方式语义，并从地理空间环境语义的角度分析了轨迹的语义多尺度；最后探讨了轨迹语义尺度与时空尺度之间的一致性关系。

Scale feature of moving trajectory

Moving trajectory is a trace of a moving object that moves in geospatial environment for a certain purpose. Featured by spatial scale, time scale and semantic scale, moving trajectory data is a special kind of geographic spatiotemporal data. Firstly, the spatial scale feature and time scale feature of moving trajectory data are analyzed in this paper, and the transformation relationship between spatial scale and time scale is established. Secondly, the semantic connotation and semantic scale feature of the trajectory are studied. Four trajectory semantic categories such as moving object, geospatial environment, moving mode and collecting equipment are proposed, and semantic multi-scale characteristics of the trajectory are analyzed from the perspective of geographical environment. Finally, the consistency relationship between the semantic scale and the space-time scale is discussed.