Rich context representation for situation aware system

Bringing sensor- and context-awareness to the Web promises to open new, tremendous business opportunities. However, context-awareness involves difficult problems such as modeling social / human affairs (e.g. law, personal preferences, etc.), handling incomplete information, and managing uncertainty of sensor data. We argue that fully-fledged, Semantic-Web-style reasoning in presence of uncertainty is neither always feasible, nor always necessary for a context-based Web. As an alternative, this paper proposes a highly expressive, simple, and efficient context representation for sensor-enabled Web services. Our representation is based on a syntax inspired by standard Semantics of Business Vocabulary and Business Rules (SBVR), enriched by annotations expressing prioritized modality and trust values. The feasibility of our approach is demonstrated via a case study for developing context/ambient-aware applications that adapt to changes in the environment.