Framework and rule-based language for facilitating context-aware computing using information appliances

Recently, context-aware computing with information appliances is the topic of many research efforts. In order to realize context-aware systems, it is necessary to describe rules, each of which consists of (1) transition condition for identifying a specific context, and (2) actions to be executed when the condition holds. However, in an ordinary home without IT specialists, it would be too complicated for each user to specify feasible rules by choosing an appropriate combination of sensors and actions, since possible combinations are so many and he/she may have even no idea on functionalities of sensors or devices. Also, multiple users may want to control the same device at the same time in different ways. In this paper, we propose a framework and a rule-based language for simply and intuitively specifying feasible rules for context-aware control of information appliances. Our framework includes mechanisms for retrieving sensors/devices to specify a condition of a rule and for detecting a conflict over multiple rules. Our prototype implementation on a PC achieves practically sufficient performance for these operations.