Vol.62 (Sensor 2014), pp.74-77

In a ubiquitous computing environment of sensor networks, monitoring the frequent contexts of a user occurred by those sensors is very important to provide a proactive service to the user. Such frequent contexts of the sensors can be recognized by associations between the set of sensor values and a set of actuator operations. This paper proposes a method of generating a new type of an association rule, called a context association rule, over an online sensor/actuator transactional data stream in order to invoke proper operations of actuators relevant to values of the sensors. To enumerate context association rules, a new prefix tree structure is introduced. It maintains all frequent context itemsets over the current data steam of sensor networks, so that a set of frequently co-occurred sensors and actuators items can be captured efficiently.