改进基于事件的时空数据模型

本文回顾了基于状态的时空数据模型和基于事件的时空数据模型。为了完整记录下时空的变化过程,有利于时空过程的查询,论文针对栅格数据提出了一种改进基于事件的时空数据模型。该模型完整地记录下地理现象的变化过程,并将地图数据的当前状态作为基图。由于大多应用中对现状图调用的最多,所以将现状图作为基图改进了系统的运行效率。最后,为了体现模型查询变化信息的优势,文章分析了一些时空查询实例。

The Improved Event-based Spatio-temporal Data Model

This paper reviewed the state-based spatio-temporal data model and the event-based spatio-temporal data model. The state-based spatio-temporal data model doesn't explicitly describe the change procedures of the map, and so does the event-based data model proposed before. To fully record the procedures of the spatio-temporal change and make it easy to query the spatio-temporal change information, an improved event-based spatio-temporal data model based on raster data was proposed here. In this improved model, the changes of the phenomena were fully recorded, and the present state of the map was set as the base map. In many applications, users fetch the present state of the map more frequently, so the improved model would make the system more efficient. In order to show its advantages that it is easy to get the changed information, this paper gave some spatio-temporal query cases. These cases illuminated clearly how to query what happened to the map at any time, such as: what event happened at a location; where did an event happen, etc. Also, this paper discussed the storage efficiency of the data model. And as a conclusion, it was suggested that the model is more suited for some conditions.