Optimization of Accurate Top-k Query in Sensor Networks with Cached Data

It is crucial to design algorithms for energy-efficient query processing for a sensor network since sensor nodes are battery-powered, and thus their lifetimes are limited. We propose a history-based approach to optimizing query processing. We apply the approach to the top-k query problem and design new algorithms. Energy consumption can be reduced by pruning unnecessary sub-queries or guiding the query to right directions. Simulation results show that energy cost can be significantly reduced. This approach can be generalized for other query problems.