地理空间元数据引擎池的设计与实现

Design and Implementation of Geometadata Engine Pool

主要探讨了"地理空间元数据引擎池"的概念及其实现,其核心问题包括2个方面,一是利用可扩展标记语言(XML)实现一体化地理空间元数据的表达;二是利用文档对象模型(DOM)实现一体化地理空间元数据的查询。前者实际上是后者的数据基础,后者则主要解决了条件查询时对地理空间元数据信息的解析和抽取。

This paper is aimed to design and implement cross-platform geometadata engine pool in National Geospatial Data Clearinghouse （NGDC）. The geometadata engine pool consists of an integrative geometadata table and a series of APIs/applications/services, with which data users can check the integrative metadata table. With Extensible Markup Language （XML）, a text-based markup language which stores data in a structured format by using meaningful tags, developers can further describe geometadata by defining meaningful tags for geometadata applications. Document Object Model （DOM）, which is used to access and manipulate the integrative geometadata table based on XML, defines the logical structure of documents and the way a document is accessed and manipulated, and provides an Application Programming Interface （API） for XML documents.