Efficient query and visualization techniques in mobile GIS environments

Continuing advances in communication technologies enable mobile users to access complex functionality like geographic information systems. Extensions to traditional interaction metaphors are needed for visual queries, decision support, and visualization to facilitate better and faster understanding in users accessing geo-spatial information. We focus on two modules of a general mobile GIS software architecture: SketchQuery and decision-centered visualization (DCV). SketchQuery enables users to freely specify graphic- und sketch-based queries in a GIS context, while the DCV approach supports decision making by integrating domain knowledge and knowledge about human situation awareness for effective informaion visualization. Efficient and user-centered interaction with GIS information is vital to the user's performance in mobile environments.