With advances in sensor techniques, much research is focused on USN (Ubiquitous Sensor Network) computing services and context analysis service is an important field among them. However, sensor stream data, which is generated from sensors used in many USN domain applications, is too fast to control each of them and the volume is too huge to store the whole data. Hence, in order to provide rapid and reliable context analysis service over such sensor stream data, a context analysis system which supports the functionality of sliding window is needed. The context model used in this system is a WHEN-DO context analysis model. This context analysis model is designed to be used as follows: If the sensor stream data satisfies condition in ‘WHEN’ clause, then it will execute actions specified in ‘DO’ clause in WHEN-DO context analysis model. Hence, this system also works as the same way. First determine if the received sensor stream data satisfies condition in ‘WHEN’ clause, if the condition is satisfied with the value of received sensor stream data, then it will execute action in ‘DO’ clause in WHEN-DO context analysis model. Using WHEN-DO context analysis model in this system can take corresponding actions according to user defined conditions. Our proposed context analysis system can be applied to many other USN environment applications such as monitoring the status of a building and then taking actions to that condition.
['Cheng Hao Jin', 'Yong-Mi Lee', 'Gyoyong Sohn', 'Hi-Seok Kim', 'Keun Ho Ryu']
Design of Context Analysis System on USN Environment