Thematic map symbol is a basic component of thematic map language and it plays an important role in expressing the thematic content. However, the extensity of users leads to the diversity and complexity of the thematic symbols and expression methods, and most of the thematic maps do not have a fixed format and norms like topographic map. At the same time, we can not require all the users to be ...

We study here how to provide the designer of geographic databases with a database query language extensible and customizable. The model presented here is a rst step toward a high level spatial query language adapted to the manipulation of thematic maps. For this, we take as an example a toy application on thematic maps, and show by using a complex objects algebra that application dependent geom...

An intelligent geoportal orchestrates (automatically coordinate) web services to prepare, discover and present information to the user. Implementations of web service standards by the Open Geospatial Consortium (OGC) and ISO/TC 211, Geographic information/Geomatics, such as, the Web Map Service (WMS), Web Feature Service (WFS) and Styled Layer Descriptor (SLD) enable the display of spatial data...

Most applications of land cover maps that have been derived from satellite data over the Arctic require higher thematic detail than available in current global maps. A range of application studies has been reviewed, including up-scaling of carbon fluxes and pools, permafrost feature mapping and transition monitoring. Early land cover mapping studies were driven by the demand to characterize wil...

Remote Sensing Images are one of the main sources of information about the earth surface. They are widely used to generate thematic maps that show the land cover. This process is traditionally done by using supervised classifiers which learn patterns extracted from few image pixels annotated by the user and then assign a label to the remaining pixels. However, due to the increasing spatial reso...

The paper has the goal to evaluate if the Universal Soil Loss Equation (USLE)applied using thematic paper maps and a DEM is sufficient to generate a model to map and predict the influences on the environment caused by soil erosion on Loess Plateau. Factors of USLE R, K, S, L, P as well as C were adapted to the test area, the Nihe Gou catchment in Chunhua County in Shaanxi. Afterwards the parame...