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Title: Towards Efficient Maintenance of Continuous MaxRS Query for Trajectories
We address the problem of efficient maintenance of the answer to a new type of query: Continuous Maximizing Range- Sum (Co-MaxRS) for moving objects trajectories. The traditional static/spatial MaxRS problem finds a location for placing the centroid of a given (axes-parallel) rectangle R so that the sum of the weights of the point-objects from a given set O inside the interior of R is maximized. However, moving objects continuously change their locations over time, so the MaxRS solution for a particular time instant need not be a solution at another time instant. In this paper, we devise the conditions under which a particular MaxRS solution may cease to be valid and a new optimal location for the query-rectangle R is needed. More specifically, we solve the problem of maintaining the trajectory of the centroid of R. In addition, we propose efficient pruning strategies (and corresponding data structures) to speed-up the process of maintaining the accuracy of the Co-MaxRS solution. We prove the correctness of our approach and present experimental evaluations over both real and synthetic datasets, demonstrating the benefits of the proposed methods.  more » « less
Award ID(s):
1646107
PAR ID:
10040589
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Proceedings of the 20th International Conference on Extending Database Technology, {EDBT} 2017, Venice, Italy, March 21-24, 2017
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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