基于GML和中介方法的空间信息查询和集成

随着WebGIS技术的日趋成熟，对于分布式的空间数据源的查询和集成也成为了GIS研究的热点。由于不同的空间数据源都有其自己的数据表示方法和结构，这种异构性给空间数据的查询和集成带来了很大的困难。提出了一种基于GML的中介方法来进行Internet多种空间数据源的查询和集成，其中使用GML技术实现对分布、异构的空间数据的包装和集成，采用SVG标准显示地理空间信息。

Approach of querying and integrating distributed spatial information based

With the development of WebGIS technology, querying and integrating distributed spatial information has become the hot spot of research. Because the different spatial information resources have different data representations and structures, this heterogeneous makes it difficult to query and integrate the spatial data. An approach of GML-based mediation is proposed to solve this heterogeneous problem. It includes two parts: wrapper and mediation. The functions of mediation are as follows: decomposing the query to some sub-queries; sending them to appropriated wrapper; and integrating the results, which can be returned by wrapper; transformming GML into SVG format. The functions of wrapper are as follows: Translating the sub-query into local query and send them to the appropriate source; transformming the spatial data into GML format.