This paper describes a motion adaptive indexing scheme for efficient evaluation of moving continual queries (MCQs) over moving objects. It uses the concept of motion-sensitive bounding boxes to model moving objects and moving queries. These bounding boxes automatically adapt their sizes to the dynamic motion behaviors of individual objects. Instead of indexing frequently changing object positions, we index less frequently changing motion sensitive bounding boxes, where updates to the bounding boxes are needed only when objects move across the boundaries. This helps decrease the number of updates to the indexes. More importantly, we use predictive query results to optimistically precalculate query results, decreasing the number of searches on the indexes. Motion-sensitive bounding boxes are used to incrementally update the predictive query results. Our experiments show that the proposed motion adaptive indexing scheme is efficient for the evaluation of moving continual range queries.
By: Bugra Gedik, Kun-Lung Wu, Philip S. Yu, Ling Liu
Published in: RC23302 in 2004
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