Rules and ontologies in support of real-time ubiquitous application

The focus of this paper is the practical evaluation of the challenges and capabilities of combination of ontologies and rules in the context of realtime ubiquitous application. The ec(h)o project designed a platform to create a museum experience that consists of a physical installation and an interactive virtual layer of three-dimensional soundscapes that are physically mapped to the museum displays. The retrieval mechanism is built on the user model and conceptual descriptions of sound objects and museum artifacts. The rule-based user model was specifically designed to work in environments where the rich semantic descriptions are available. The retrieval criteria are represented as inference rules that combine knowledge from psychoacoustics and cognitive domains with compositional aspects of interaction. Evaluation results both from the laboratory and museum deployment testing are presented together with the end user usability evaluations. We also summarize our findings in the lessons learned that provide a transferable generic knowledge for similar type of applications. The ec(h)o proved that ontologies and rules provide an excellent platform for building a highly-responsive context-aware interactive application.