KREVELD , Marc Van

A rectangular cartogram is a type of map where every region is a rectangle. The size of the rectangles is chosen such that their areas represent a geographic variable (for example population). Rectangular cartograms are a useful tool to visualize statistical data. However, good cartograms are generally hard to generate: The area specifications...

A polyhedral terrain is the image of a piecewise linear continuous function de ned over the triangles of a triangulation in the xy- plane. Given a terrain with n vertices, two simply-connected regions (subsets of the triangles), and any constant e > 0, we an determine in O(n2+e) time and storage whether or not the two regions are completely...

Geographic Information Retrieval is concerned with retrieving documents that are related to some location. This paper addresses the ranking of documents by both textual relevance and spatial relevance. To this end, we introduce distributed ranking, where similar documents are ranked spreaded in the list instead of sequentially. The effect of...