Land-using Data Sharing Research Based On Geography Markup Language

With the end of the Second National Land Survey, the land-use databases have been established based on GIS technology. However, because of using different GIS systems made by different manufacturers, various types of GIS systems are like the "black box" organization, which can not access each other's data transparently. The sharing of real-time data can not come true in the current network environment, although using the uniform data format (VCT). Geography Markup Language (GML) brings the hope for data sharing, which is promulgated by Open Geospatial Consortium. GML is a new model of spatial data based on XML and a special specification for spatial data sharing and exchanging on Web. It can describe different complex data and separate the data content from the data format, so it is possible to depict different data source by the uniform spatial data model. OGC has also developed the technical framework for OGC Web Service, which provide basis for the realization of multiple heterogeneous spatial data sharing and cross-platform operation.In this paper, the author puts emphasis on the study of the related theory and the key technology of GML and Web Service, and achieves land use data sharing with technology of C#. The thesis covers following parts:Firstly, this paper analyzes land use data sharing insufficient of the traditional methods, then introduces GML to solve the issues; Secondly, the author completed the construction of land-use database, through investigated,collected and processed land-use data; Thirdly, the author established land-use spatial data model according to the national standard-gml3.2 specification and the modeling tool-XML Spy 2008; Fourthly, the author designed the process to generate GML documents according to the shape file data format and land-use spatial data model; Fifthly, the author has studied methods to analyze GML documents, and designed a system to query and display GML graph data, the system have many functions, such as:displaying graphic data, querying, layer controlling and displaying coordinate information; Sixthly, the author has studied OGC Web Service framework and WFS specification, at last, achieved the aim of land use data sharing.This study shows that GML can express spatial data information and is very effective to share the spatial information. Because of limited ability and time, the sharing of spatial data need further study.