Application of GIS spatio-temporal data model in urban underground pipeline database;

We must check the quality of GIS spatial data.

This paper presents a technical method for hiding digital watermark in GIS spatial data, which can identify the data producer and legal user s identity, user s using authority and some other related information, then compresses and encrypts the GIS data in order to track and resist the illegal circulation and copy to protect the data producer s legal right effectively.

Beginning from the character of GIS spatial data and shortcoming of GIS spatial data s applying in map pre-publishing technology,the thesis discusses the key problems on the organization of layer,the management of symbol library,the choice of font library, the applying of map label.

In order to satisfy the function demand of freeway safety management system,a data model for freeway traffic networks based on traffic flow characteristics is presented,which facilitates the GIS expression,operation and analysis of freeway traffic networks data,and offsets the deficiency of the existing GIS data model for traffic networks on modeling and analysis of complex networks.

By using GIS method, a wetlands GIS spatial database of Heilongjiang province was built based on collecting a vast amount of wetlands data.