Event

Context and Situations in Location-based Services

Agnes Voisard

ICSI

Wednesday, October 15, 2008
2:00 pm

Location-based services, which answer queries such as “Where is the nearest subway station” or “What are the exhibitions in this city today?”, are currently receiving a great deal of interest from many communities. Given the dynamics inherent to mobile applications, handling the user demand – being explicit or implicit – goes beyond profile understanding. It requires in particular the consideration of the user’s current context, such as his or her location, but also current activity, connectivity, and planning. Context thus needs to be captured in a highly dynamic manner along many dimensions. The context gathered in a particular time interval determines a situation. For instance, when the situation of a user is “driving”, he or she would like to be kept updated on the (current) traffic or weather conditions in some area and notified if there is congestion on his or her route or the risk of a storm. Situations are derived from basic sensors but also from more elaborate concepts such as histories or planned activities. This simple yet powerful concept helps designers to abstract from raw contextual information.

This talk will present a situation model that handles efficiently the multi-dimensional context of mobile entities. We will also show how the model has been applied in several projects of the “Location-based Services” department of Fraunhofer ISST in Berlin.