Abstract
One of the most important queries in spatio-temporal databases that aim at managing moving objects efficiently is the continuous K-nearest neighbor (CKNN) query. A CKNN query is to retrieve the K-nearest neighbors (KNNs) of a moving user at each time instant within a user-given time interval [t s , t e ]. In this paper, we investigate how to process a CKNN query efficiently. Different from the previous related works, our work relieves the past assumption, that an object moves with a fixed velocity, by allowing that the velocity of the object can vary within a known range. Due to the introduction of this uncertainty on the velocity of each object, processing a CKNN query becomes much more complicated. We will discuss the complications incurred by this uncertainty and propose a cost-effective P2 KNN algorithm to find the objects that could be the KNNs at each time instant within the given query time interval. Besides, a probability-based model is designed to quantify the possibility of each object being one of the KNNs. Comprehensive experiments demonstrate the efficiency and the effectiveness of the proposed approach.
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References
V.T. de Almedia. “Towards optimal continuous nearest neighbor queries in spatial databases,” in Proceedings of ACM GIS, November 10–11, 2006.
R. Benetis, C.S. Jensen, G. Karciauskas, and S. Saltenis. “Nearest neighbor and reverse nearest neighbor queries for moving objects,” in Proceedings of the International Database Engineering and Applications Symposium, Canada, July 17–19, 2002.
R. Benetis, C.S. Jensen, G. Karciauskas, and S. Saltenis. “Nearest neighbor and reverse nearest neighbor queries for moving objects,” VLDB Journal, Vol. 15(3):229–249, 2006.
M.R. Kolahdouzan and C. Shahabi. “Alternative solurions for continuous K nearest neighbor in spatial network databases,” GeoInformatica, Vol. 9(4):321–341, June 2004.
M.R. Kolahdouzan and C. Shahabi. “Continuous K nearest neighbor queries in spatial network databases,” in Proceedings of the Second Workshop on Spatio-Temporal Database Management, August 30, 2004.
R. Cheng, D.V. Kalashnikov, and S. Prabhakar. “Querying imprecise data in moving object environments,” IEEE Transactions on Knowledge and Data Engineering, Vol. 16(9):1112–1127, 2004.
G. Iwerks, H. Samet, and K. Smith. “Continuous K-nearest neighbor queries for continuously moving points with updates,” in Proceedings of the International Conference on Very Large Data Bases, Berlin, Germany, September 9–12, 2003.
K.C.K. Lee, H.V. Leong, J. Zhou, and A. Si. “An efficient algorithm for predictive continuous nearest neighbor query processing and result maintenance,” in Proceedings of the International Conference on Mobile Data Management, 2005.
K. Mouratidis, M. Hadjieleftheriou, and D. Papadias. “Conceptual partitioning: An efficient method for continuous nearest neighbor monitoring,” in Proceedings of the ACM SIGMOD International Conference on Management of Data, 2005.
D. Papadias, Q. Shen, Y. Tao, and K. Mouratidis. “Group nearest neighbor queries,” in Proceedings of the International Conference on Data Engineering, 2004.
K. Raptopoulou, A.N. Papadopoulos, and Y. Manolopoulos. “Fast nearest-neighbor query processing in moving-object databases,” GeoInformatica, Vol. 7(2):113–137, June 2003.
S. Saltenis, C.S. Jensen, S.T. Leutenegger, and M.A. Lopez. “Indexing the positions of continuously moving objects,” in Proceedings of the ACM SIGMOD International Conference on Management of Data, 2000.
Z. Song and N. Roussopoulos. “K-nearest neighbor search for moving query point,” in Proceedings of 7th International Symposium on Advances in Spatial and Temporal Databases, Redondo Beach, CA, USA, July 12–15, 2001.
A.P. Sistla, O. Wolfson, S. Chamberlain, and S. Dao. “Modeling and querying moving objects,” in Proceedings of the International Conference on Data Engineering, 1997.
Y. Tao, C. Faloutsos, D. Papadias, and B. Liu. “Prediction and indexing of moving objects with unknown motion patterns,” in Proceedings of the ACM SIGNOD, Maison de la Chimie, Paris, France, June 13–18, 2004.
Y. Tao and D. Papadias. “Time parameterized queries in spatio-temporal databases,” in Proceedings of the ACM SIGMOD, Madison, Wisconsin, 2002.
Y. Tao, D. Papadias, and Q. Shen. “Continuous nearest neighbor search,” in International Conference on Very Large Data Bases, Hong Kong, China, August 20–23, 2002.
O. Wolfson, A.P. Sistla, S. Chamberlain, and Y. Yesha. “Updating and querying databases that track mobile units,” Distributed and Parallel Databases, Vol. 7(3):257–387, 1999.
X. Xiong, M.F. Mokbel, and W.G. Aref. “SEA-CNN: Scalable processing of continuous k-nearest neighbor queries in spatio-temporal databases,” in Proceedings of the International Conference on Data Engineering, 2005.
X. Yu, K.Q. Pu, and N. Koudas. “Monitoring K-nearest neighbor queries over moving objects,” in Proceedings of the International Conference on Data Engineering, 2005.
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This work was supported by National Science Council of Taiwan (R.O.C.) under Grants NSC95-2221-E-006-206-MY3 and NSC95-2221-E-006-208.
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Huang, YK., Chen, CC. & Lee, C. Continuous K-Nearest Neighbor Query for Moving Objects with Uncertain Velocity. Geoinformatica 13, 1–25 (2009). https://doi.org/10.1007/s10707-007-0041-0
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DOI: https://doi.org/10.1007/s10707-007-0041-0