News and Events

Perceptual Sketch Interpretation

Published: Jun 1, 2008 Author(s): Egenhofer, Max J., Wuersch, Markus Abstract: An automated extraction of regions from sketches can be of great value for multi-modal user interfaces and for interpreting spatial data. This paper develops the Perceptual Sketch Interpretationalgorithm, which employs the theory of topological relations from spatial reasoning as well as continuity and good gestalt from gestalt theory […]

Read more

Conceptual Neighborhoods of Topological Relations between Lines

Published: Jun 1, 2008 Author(s): Egenhofer, Max J., Matos, Joao, Reis, Rui Abstract: Conceptual neighborhood graphs capture the similarity among qualitative relations. This paper derives the graphs for the thirty-three topological relations between two crisp, undirected lines and for the seventy-seven topological relations between two lines with uncertain boundaries. The analysis of the graphs shows that the normalized node […]

Read more

SIE students participate in Graduate Research Exposition

The 10th Annual Graduate Research Exposition was held April 15-16, 2008, in the Buchanan Alumni House at the University of Maine. The Expo, which is organized by UMaine’s Graduate Student Government, is an opportunity for graduate students to showcase academic excellence and creative achievement. Graduate students from the Department of Spatial Information Science and Engineering […]

Read more

Geo-Mobile Query-by-Sketch

Published: Jan 1, 2007 Author(s): Caduff, David, Egenhofer, Max J. Abstract: The advent of wireless technology, such as cellphones, PDAs, tablet PCs, and sub-notebooks, allows tranferring portions of traditional desktop-based GIS technology to mobile environments. This paper introduces Geo-Mobile Query-by-Sketch, a sketch-based spatial querying system for mobile GIS environment that combines techniques for spatial querying with mobile technologies. […]

Read more

The Head-Body-Tail Intersection for Spatial Relations Between Directed Line Segments

Published: Jan 1, 2006 Author(s): Egenhofer, Max J., Kurata, Yohei Abstract: Directed line segments are fundamental geometric elements used to model through their spatial relations such concepts as divergence, confluence, and interference. A new model is developed that captures spatial relations between pairs of directed line segments through the intersections of the segments’ heads, bodies, and tails. This […]

Read more

Changes in Topological Relations when Splitting and Merging Regions

Published: Jan 1, 2006 Author(s): Egenhofer, Max J., Wilmsen, Dominik Abstract: This paper addresses changes in topological relations as they occur when splitting a region into two. It derives systematically what qualitative inferences can be made about binary topological relations when one region is cut into two pieces. The new insights about the possible topological relations obtained after […]

Read more

GeoSpatial Semantics–First International Conference, GeoS 2005

A. Rodríguez, I. Cruz, M. Egenhofer, and S. Levashkin (editors), GeoSpatial Semantics–First International Conference, GeoS 2005, Lecture Notes in Computer Science, Vol. 3799, Spinger, New York, 2005. This book contains the fully refereed papers of the First International Symposium on Geospatial Semantics, GeoS 2005, to be held in Mexico City, Mexico in November 2005.

Read more

Ontology-Driven Map Generalization

Published: Jan 1, 2005 Author(s): Duckham, Matt, Egenhofer, Max J., Kulik, Lars Abstract: Different users of geospatial information have different requirements of that information. Matching information to users’ requirements demands an understanding of the ontological aspects of geospatial data. In this paper, we present an ontology-driven map generalization algorithm, called DMin, that can be tailored to particular users and […]

Read more

Spherical Topological Relations

Published: Jan 1, 2005 Author(s): Egenhofer, Max J. Abstract: Analysis of global geographic phenomena requires non-planar models. In the past, models for topological relations have focused either on a two-dimensional or a three-dimensional space. When applied to the surface of a sphere, however, neither of the two models suffices. For the two-dimensional planar case, the eight binary […]

Read more