Online Time Interval Top-k Queries in Wireless Sensor Networks

13 years 9 months ago

Download cs.anu.edu.au

Motivated by many applications, top-k query is a fundamental operation in modern database systems. Technological advances have enabled the deployment of large-scale sensor networks for environmental monitoring and surveillance purposes, efﬁcient processing of top-k query in such networks poses great challenges due to the unique characteristics of sensors and a vast amount of data generated by sensor networks. In this paper, we ﬁrst introduce the concept of time interval top-k query that is to return k highest sensed values from the sensory data generated within a speciﬁed time interval. We then propose a ﬁlter-based algorithm for time interval top-k query evaluation, which is capable to ﬁlter out nearly a half unlikely top-k data from transmission in comparison with a well known existing solution. We also develop a novel online algorithm for answering time interval top-k queries with various ks and time intervals one by one through maintaining a materialized view that consist...

Baichen Chen, Weifa Liang, Jeffrey Xu Yu

Real-time Traffic