Context modeling and reasoning based on certainty factor

Context-aware computing is an emerging computing paradigm that provides intelligent context-aware application. Its core idea is to have computers understand the real world so that human-computer interactions can happen at a much higher abstraction level, hence to make the interactions much more pleasant or transparent to human users. Context-awareness is the key to achieve this goal. It entails a complex process that involves a diversity of development aspects, such as acquisition, reasoning, representation and utilization of context information. In this paper we tackle context-awareness in the context modeling and reasoning aspects. We analyze the hierarchical structure of context information, propose a hierarchy context reasoning model accordingly and describe the procedure and principles of model construction in detail. Then a reasoning rule based on certainty factor is presented and at last a case is put forward to show the whole process of context modeling and reasoning.