Christopher E. Frank

A THESIS
Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science (in Spatial Information Science and Engineering)

The Graduate School
The University of Maine
December, 2003 

People navigate for very different reasons, whether they are utility workers, soldiers, or tourists. Many of the basic problems they encounter are similar, because much of the information people want or need cannot be directly interpreted from their surroundings. It is this problem of not being able to gather the right information from their surroundings that can lead people to getting lost. At any given intersection turning right might look just as adequate as turning left (Raubal and Worboys 1999); therefore, people who have never been to a place before and do not have a mental model of the environment use maps, which give them a panoptic view of the area. Maps are also useful as they provide information about a place that is not apparent to a person’s senses. For example, looking at a building one might be able to tell that it is a church but not when it was built, or what the overall shape of the church is (Stea et al. 1996). It is these problems people have interacting with foreign environments that has led to this research of egocentric mobile geographic information systems (GIS's).

To help people deal with the problems that arise from traveling, different types of navigational aids exist. These navigational aids have many different forms and some have existed for centuries. The goal of these aids is to improve people’s wayfinding abilities and increase their cultural connection with a foreign space. The objective of this paper is to develop a query model for spatially-aware egocentric GISs. This egocentric query model allows a location-based information system to accurately process users questions pertaining to their perception of here, and there.