2008-To Appear

• Ke Yi, Feifei Li, George Kollios, and Divesh Srivastava. Efficient Processing of Top-k Queries in Uncertain Databases with x-Relations. To Appear in IEEE TKDE .
• Vassilis Athitsos, Panagiotis Papapetrou, Michalis Potamias, George Kollios, and Dimitrios Gunopulos. Approximate Embedding-Based Subsequence Matching of Time Series. To Appear in the Proc. of the 28th ACM SIGMOD International Conference on Management of Data, Vancouver, Canada, June 2008. [PDF]
• Ke Yi, Feifei Li, Marios Hadjieleftheriou, Divesh Srivastava, and George Kollios. Randomized Synopses for Query Assurance on Data Streams. Proc. of the 24th IEEE ICDE International Conference on Data Engineering, Cancun, Mexico, April 2008. [PDF]
• Ying Yang, Stavros Papadopoulos, Dimitris Papadias, and George Kollios. Spatial Outsourcing for Location-based Services. Proc. of the 24th IEEE ICDE International Conference on Data Engineering, Cancun, Mexico, April 2008. [PDF]
• Vassilis Athitsos, Michalis Potamias, Panagiotis Papapetrou, and George Kollios. Nearest Neighbor Retrieval Using Distance-Based Hashing. Proc. of the 24th IEEE ICDE International Conference on Data Engineering, Cancun, Mexico, April 2008. [PDF]
• Ke Yi, Feifei Li, Divesh Srivastava, and George Kollios. Efficient Processing of Top-k Queries in Uncertain Databases. Proc. of the 24th IEEE ICDE International Conference on Data Engineering, Cancun, Mexico, April 2008. [PDF]
• Vassilis Athitsos, Jonathan Alon, Stan Sclaroff, and George Kollios. BoostMap: An Embedding Method for Efficient Nearest Neighbor Retrieval. IEEE PAMI Vol. 30, No. 1, January 2008. [PDF]

• Feifei Li, Marios Hadjieleftheriou, George Kollios, and Leonid Reyzin. Authenticated Index Structures for Outsourced Databases. Book Chapter in Handbook of Database Security: Applications and Trends , Michael Gertz and Sushil Jajodia (Editors), Springer, November 2007. [PDF]
• Spiros Papadimitriou, Feifei Li, George Kollios, and Philip S. Yu. Time Series Compressibility and Privacy. Proc. of the 33rd VLDB International Conference on Very Large Databases, Vienna, Austria, September 2007. [PDF]
• Feifei Li, Ke Yi, Marios Hadjieleftheriou, and George Kollios. Proof-Infused Streams: Enabling Authentication of Sliding Window Queries On Streams. Proc. of the 33rd VLDB International Conference on Very Large Databases, Vienna, Austria, September 2007. [ PDF]
• Vassilis Athitsos, Marios Hadjieleftheriou, George Kollios, and Stan Sclaroff. Query-Sensitive Embeddings. ACM TODS, Vol. 32, No. 2, June 2007. [PDF]
• Vassil Kriakov, Alex Delis, and George Kollios. Approximate Data Stream Joins in Distributed Systems . To Appear in the Proc. of the 27th IEEE ICDCS International Conference on Distributed Computing Systems ,Toronto, Canada, June 2007.
• Nikolaos Laoutaris, Georgios Zervas, Azer Bestavros, and George Kollios. The Cache Inference Problem and its Application to Content and Request Routing. Proc. of the 26th IEEE INFOCOM Annual Conference on Computer Communications,Anchorage, Alaska, May 2007. [PDF]
• Stilian Stoev, Marios Hadjieleftheriou, George Kollios, and Murad Taqqu. Norm, Point, and Distance Estimation Over Multiple Signals Using Max-Stable Distributions. Proc. of the 23rd IEEE ICDE International Conference on Data Engineering , Istanbul, Turkey, April 2007. [PDF]

• Jimeng Sun, Yufei Tao, Dimitris Papadias, and George Kollios. Spatio-Temporal Join Selectivity. Information Systems, Vol. 31, No. 8, pp. 793-813, December 2006. [PDF]
• Marios Hadjieleftheriou, George Kollios, Vassilis Tsotras, and Dimitris Gunopulos.  Indexing Spatio-Temporal Archives. VLDB Journal, Vol. 15, No. 2, pp. 143-164, June 2006. [PDF]
• Feifei Li, Marios Hadjieleftheriou, George Kollios, and Leonid Reyzin. Dynamic Authenticated Index Structures for Outsourced Databases. Proc. of the 25th ACM SIGMOD International Conference on Management of Data, Chicago, Illinois, June 2006. [PDF]
• Feifei Li, Ching Chang, George Kollios, and Azer Bestavros. Characterizing and Exploiting Reference Locality in Data Stream Applications.
  Proc. of the 22nd IEEE International Conference on Data Engineering (ICDE), Atlanta, Georgia, USA, April 2006. [PDF]

• Panfeng Zhou, Betty Salzberg, Donghui Zhang, Gene Cooperman, and George Kollios. Close Pair Queries in Moving Object Databases. Proc. of the 13th ACM International Symposium on Geographic Information Systems (GIS), Bremen, Germany, 2005. [PDF]
  
• Panagiotis Papapetrou, George Kollios, Stan Sclaroff, and Dimitrios Gunopulos. Discovering Frequent Arrangements of Temporal Intervals. Proc. of the 5th IEEE International Conference on Data Mining (ICDM), New Orleans, Luisiana, USA, November 2005. [PDF]
• Marios Hadjieletheriou, George Kollios, Petko Bakalov, and Vassilis Tsotras. Complex Spatio-Temporal Pattern Queries. Proc. of the 31st International Conference on Very Large Data Bases (VLDB), Trondheim, Norway, August 2005. [PDF]
• Feifei Li, Dihan Chen, Marios Hadjieleftheriou, George Kollios, and Shang-Hua Teng. On Trip Planning Queries in Spatial Databases. Proc. of the 9th International Symposium on Spatial and Temporal Databases (SSTD), Angra dos Reis, Brazil, August 2005. [PS]
  
• Vassilis Athitsos, Marios Hadjieletheriou, George Kollios, and  Stan  Sclaroff. Query-Sensitive Embeddings. Proc. of the 24th ACM SIGMOD International Conference on Management of Data, Baltimore, Maryland, June 2005. [PDF]
  
• George Kollios, Dimitris Papadopoulos, Dimitrios Gunopulos, and Vassilis Tsotras. Indexing Mobile Objects Using Dual Transformations. VLDB Journal, Vol. 14, No. 2, pp. 238-256, April 2005. [PDF]
  
• Dimitrios Gunopulos, George Kollios, Vassilis Tsotras, and  Carlotta Domeniconi. Selectivity Estimators for Multi-Dimensional Range Queries Over Real Attributes. VLDB Journal, Vol. 14, No. 2, pp. 137-154, April 2005.  [PDF]
• Michail Vlachos, George Kollios, and Dimitrios Gunopulos. Elastic Translation Invariant Matching of Trajectories. Machine Learning Journal, Vol. 58, No. 2, pp. 301-334, February 2005. [PDF]

• Nikos Mamoulis, Huping Cao, George Kollios, Marios Hadjieleftheriou, Yufei Tao, and David Cheung. Mining, Indexing, and Querying Historical Spatio-Temporal Data. Proceedings of the  10th ACM International Conference on Knowledge Discovery and Data Mining (SIGKDD), Seattle, WA, August 2004. [PDF]
• Marios Hadjieleftheriou, Vassil Kriakov, Yangui Tao, George Kollios, Alex Delis, and Vassilis Tsotras. Spatio-Temporal Data Services in a Shared-Nothing Environment. Proceedings of the 16th International Conference on Scientific and Statistical Database Management (SSDBM), Santorini, Greece, June 2004. (Short Paper)  [PDF]
  
• Vassilis Athitsos, Jonathan Alon, Stan  Sclaroff, and George  Kollios. BoostMap: A Method for Efficient Approximate Similarity Rankings. Proceedings of the IEEE CVPR 2004.  Washington, DC, June 2004. [PDF]
  
• Vassil Kriakov, Alex Delis, and George Kollios. Management of Highly Dynamic Multidimensional Data in a Cluster of Workstations. Proceedings of the 9th Conference on Extending Database Technology (EDBT), Greece, 2004. [PDF]
• Jeffrey Considine, Feifei  Li, George Kollios, and John Byers. Approximate Aggregation Techniques for Sensor Databases.  Proceedings of 20th IEEE International Conference on Data Engineering (ICDE), Boston, MA, March 30 - April 2, 2004.  [PDF]
  
• Yufei Tao, George Kollios, Jeffrey Considine, Feifei  Li, and Dimitris Papadias. Spatio-Temporal Aggregation Using Sketches. Proceedings of 20th IEEE International Conference on Data Engineering (ICDE), Boston, MA, March 30 - April 2, 2004. [PDF]

• Marios Hadjieleftheriou, George Kollios, Vassilis Tsotras, and Dimitris Gunopulos.  On-Line Discovery of Dense Areas in Spatio-temporal Databases. Proceedings of the 8th International Symposium on Spatial and Temporal Databases (SSTD),  Santorini, Greece, July 2003. [PDF]
  
• Marios Hadjieleftheriou, George Kollios, and Vassilis Tsotras. Performance Evaluation of Spatio-temporal Selectivity Estimation Techniques. Proceedings of the 15th International Conference on Scientific and Statistical Database Management (SSDBM), Cambridge, Massachusetts, July 2003. [PDF]
  
• Jonathan Alon, Stan  Sclaroff, George  Kollios, and Vladimir Pavlovic. Discovering Clusters in Motion Time-Series Data. Proceedings of the IEEE CVPR 2003. Madison, Wisconsin, June 2003. [PDF]
  
• George Kollios, Dimitrios Gunopulos, Nick Koudas, and Stephan Berchtold. Efficient Biased Sampling for Approximate Clustering and Outlier Detection in Large Datasets. IEEE Transactions on Knowledge and Data Engineering, September/October 2003. [ps.gz]

• George Kollios and Vassilis Tsotras. Hashing Methods for Temporal Data.  IEEE Transactions on Knowledge and Data Engineering, July/August 2002.  [PS]
• Dimitris Papadopoulos, George Kollios, Dimitrios Gunopulos, and Vassilis Tsotras. Indexing Mobile Objects Using Duality Transforms. IEEE Data Engineering Bulletin (25):2, 2002. (Invited paper)
• Michail Vlachos, Carlotta Domeniconi, Dimitrios Gunopulos, George Kollios, and Nick Koudas. Non-Linear Dimensionality Reduction Techniques for Classification and Visualization. Proc. of the  8th ACM SIGKDD , Edmonton, Canada, 2002. [PS]
• Michail Vlachos, Dimitrios Gunopulos, and George Kollios. Robust Similarity Measures for Mobile Object Trajectories. MDDS 02, Aix-en-Provence, France, 2002. [PS]
•  Dimitris Papadopoulos, George Kollios, Dimitrios Gunopulos, and Vassilis Tsotras. Indexing Mobile Objects on the Plane. MDDS 02, Aix-en-Provence, France, 2002. [PS]
• Michail Vlachos, George Kollios, and  Dimitrios Gunopulos. Discovering Similar Multi-dimensional Trajectories. Proc. of  the18th IEEE International Conference on Data Engineering, San Jose, 2002. [PS]
• Marios Hadjieleftheriou, George Kollios, Vassilis Tsotras, and Dimitrios Gunopulos. Efficient Indexing of Spatio-temporal Objects. Proc of the 8th Conference on Extending Database Technology (EDBT), Prague, 2002. [PDF]

• George Kollios, Dimitrios Gunopulos, Vassilis Tsotras,  Alex Delis, and Marios Hadjieleftheriou. Indexing Animated Objects Using Spatiotemporal Access Methods. IEEE Transactions on Knowledge and Data Engineering, September 2001.  [PS]
• George Kollios, Dimitrios Gunopulos, Nick Koudas, and Stefan Berchtold. An Efficient Approximation Scheme for Data Mining Tasks. In Proc. of the 17th IEEE International Conference on Data Engineering, Heidelberg, Germany, April 2-6, 2001. [PS]
• George  Kollios, Stan Sclaroff, and Margrit Betke. Motion Mining: Discovering Spatio-Temporal Patterns in Databases of Human Motion. Workshop on Research Issues in Data Mining and Knowledge Discovery, DMKD 2001, Santa Barbara, CA, May 2001.
• Stan Sclaroff, George Kollios, Margrit Betke, and Romer Rosales. Motion Mining. Proc. of 2nd MDIC, Italy, 2001. (Invited paper)

• Dimitrios Gunopulos, George Kollios, Vassilis Tsotras, and Carlotta Domeniconi. Approximating Multi-Dimensional Aggregate Range Queries Over Real Attributes. In Proc .of the  19th ACM SIGMOD Intl. Conference on Management of Data, Dallas, TX, 2000. [PS]
• Lifei Tan, Vassilis Tsotras, George Kollios, and Dimitrios Gunopulos. Multidimensional Membership Queries for Temporal Databases. In Proc. of the Twelfth International Conference on Software Engineering and Knowledge Engineering, Chicago, 2000. [PS]
• Dimitrios Gunopulos, G. Kollios, V. Tsotras, and C. Domeniconi: Using kernels to approximate multi-dimensional aggregate range queries over real attributes. Workshop on New Perspectives in Kernel-Based Learning Methods, NIPS 2000.

• George Kollios, Dimitrios Gunopulos, and Vassilis Tsotras. On Indexing Mobile Objects. In Proc. of the 18th ACM Symp. on Principles of Database Systems, PODS '99, Philadelphia, PA, 1999. [PS]
• Joseph Hellerstein , Lisa Hellerstein, and George Kollios. On the Generation of 2-Dimensional Index Workloads. In Proc. of the 7th International Conference on Database Theory,ICDT '99, Jerusalem, Israel, 1999. [PS] [PDF]
• George Kollios, Dimitrios Gunopulos, and Vassilis Tsotras. Nearest Neighbor Queries in a Mobile Environment. In Proc. Int. Workshop on Spatio-temporal Databases, STDBM'99, Edinburgh, Scotland, 1999.  (LCNS 1678) [PS]
• George Kollios, Dimitrios Gunopulos, and Vassilis Tsotras. Indexing Animated Objects. In Proc. 5th Int. Workshop on Multimedia Information Systems, MIS '99, Palm Springs Desert, CA,  1999. [PS]
• Alex Delis, Vinay Kanitkar, and  George Kollios. Database Architectures. Book  Chapter in the Encyclopedia of Electrical and Electronics Engineering, John Wiley and Sons, Inc., 1999.