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1. X. Lin, J. Xu, and H. Hu. "Range-based Skyline Queries in Mobile Environments." IEEE Transactions on Knowledge and Data Engineering (TKDE), accepted to appear, 2011. [DOI Bookmark]
2. S. T. On, J. Xu, B. Choi, H. Hu, and B. He. "Flag Commit: Supporting Efficient Transaction Recovery in Flash-based DBMSs." IEEE Transactions on Knowledge and Data Engineering (TKDE), accepted to appear, 2011. [DOI Bookmark]
3. X. Pan, J. Xu, and X. Meng. "Protecting Location Privacy against Location-Dependent Attacks in Mobile Services." IEEE Transactions on Knowledge and Data Engineering (TKDE), accepted to appear, 2011. [DOI Bookmark]
4. Y. Tang, J. Xu, S. Zhou, W.-C. Lee, D. Deng, and Y. Wang. "A Lightweight Multi-dimensional Index for Complex Queries over DHTs." IEEE Transactions on Parallel and Distributed Systems (TPDS), 22(12): 2046-2054, Dec. 2011. [DOI Bookmark]
5. D. Wang, J. Xu, F. Wang, and J. Liu. "Mobile Filter: Exploring Migration of Filters for Error-Bounded Continuous Data Collection in Sensor Networks." IEEE Transactions on Vehicular Technology (TVT), Oct. 2010. [pdf]
6. H. Hu, J. Xu, S. T. On, J. Du, and J. K. Ng. "Privacy-Aware Location Data Publishing." ACM Transactions on Database Systems (TODS), 35(3), July 2010. [pdf]
7. H. Hu and J. Xu. "2PASS: Bandwidth-Optimized Location Cloaking for Anonymous Location-Based Services." IEEE Transactions on Parallel and Distributed Systems (TPDS), 21(10): 1458-1472, October 2010. [pdf]
8. J. Xu, X. Tang, H. Hu, and J. Du. "Privacy-Conscious Location-Based Queries in Mobile Environments." IEEE Transactions on Parallel and Distributed Systems (TPDS), 21(3): 313-326, March 2010. [pdf]
9. H. Hu, J. Xu, and D. L. Lee. "PAM: An Efficient and Privacy-Aware Monitoring Framework for Continuously Moving Objects." IEEE Transactions on Knowledge and Data Engineering (TKDE), 22(3): 404-419, March 2010. [pdf]
10. Y. Tang, S. Zhou, and J. Xu. "LIGHT: A Query-Efficient yet Low-Maintenance Indexing Scheme over DHTs." IEEE Transactions on Knowledge and Data Engineering (TKDE), 22(1): 59-75, Jan. 2010. [pdf]
11. X. Tang, J. Xu, and W.-C. Lee. "Analysis of TTL-Based Consistency in Unstructured Peer-to-Peer Networks." IEEE Transactions on Parallel and Distributed Systems (TPDS), 19(12): 1683-1694, Dec. 2008. [pdf]
12. X. Tang and J. Xu. "Optimizing Lifetime for Continuous Data Aggregation with Precision Guarantees in Wireless Sensor Networks." ACM/IEEE Transactions on Networking (ToN), 16(4): 904-917, August 2008. [pdf]
13. X. Tang and J. Xu. "Adaptive Data Collection Strategies for Lifetime-Constrained Wireless Sensor Networks." IEEE Transactions on Parallel and Distributed Systems (TPDS), 19(6): 721-734, June 2008. [pdf]
14. J. Xu, X. Tang, and W.-C. Lee. "A New Storage Scheme for Approximate Location Queries in Object Tracking Sensor Networks." IEEE Transactions on Parallel and Distributed Systems (TPDS), 19(2): 262-275, Feb. 2008. [pdf]
15. M. Wu, J. Xu, X. Tang, and W.-C. Lee. "Top-k Monitoring in Wireless Sensor Networks." IEEE Transactions on Knowledge and Data Engineering (TKDE), 19(7): 962-976, July 2007. [pdf]
16. J. Liu, J. Xu, and X.-W. Chu. "Fine-Grained Scalable Video Caching for Heterogeneous Clients." IEEE Transactions on Multimedia(TMM), 8(5): 1011-1020, Oct. 2006. [pdf]
17. J. Xu, W.-C. Lee, X. Tang, Q. Gao, and S. Li. "An Error-Resilient and Tunable Distributed Indexing Scheme for Wireless Data Broadcast." IEEE Transactions on Knowledge and Data Engineering (TKDE), 18(3): 392-404, March 2006. [pdf, supplemental material]
18. J. Xu, X. Tang, and W.-C. Lee. "Scheduling Time-Critical On-Demand Broadcast: Algorithms, Analysis, and Performance Evaluation." IEEE Transactions on Parallel and Distributed Systems (TPDS), 17(1): 3-14, Jan. 2006. [pdf, supplemental material]
19. B. Zheng, J. Xu, W.-C. Lee, and D. L. Lee. "Grid-Partition Index: A Hybrid Method for Nearest-Neighbor Queries in Wireless Location-Based Services." VLDB Journal (VLDBJ), 15(1):21-39, Jan. 2006. [pdf]
20. X. Tang and J. Xu. "QoS-Aware Replica Placement for Content Distribution." IEEE Transactions on Parallel and Distributed Systems (TPDS), 16(10): 921-932, Oct. 2005. [pdf]
21. J. Xu, B. Zheng, W.-C. Lee, and D. L. Lee. "The D-tree: An Index Structure for Planar Point Queries in Location-Based Wireless Services." IEEE Transactions on Knowledge and Data Engineering (TKDE), 16(12): 1526-1542, Dec. 2004. [pdf]
22. J. Liu and J. Xu. "Proxy Caching for Media Streaming over the Internet." IEEE Communications Magazine, 42(8): 88-94, August 2004. [pdf]
23. J. Xu, J. Liu, B. Li, and X. Jia. "Caching and Prefetching for Web Content Distribution." IEEE Computing in Science and Engineering (CiSE), Special Issue on Web Engineering, 6(4): 54-59, July/August 2004. [pdf, an extended version]
24. J. Xu, Q. Hu, W.-C. Lee, and D. L. Lee. "Performance Evaluation of an Optimal Cache Replacement Policy for Wireless Data Dissemination." IEEE Transactions on Knowledge and Data Engineering (TKDE), 16(1): 125-139, Jan. 2004. [pdf]
25. D. L. Lee, K. K. Hoi, J. Xu, and W. S. D. Wong. "Web Browsing on Small Displays." IEEE Distributed Systems Online, Vol. 4, No. 10, Oct 2003. [html]
26. J. Xu, X. Tang, and D. L. Lee. "Performance Analysis of Location-Dependent Cache Invalidation Schemes for Mobile Environments." IEEE Transactions on Knowledge and Data Engineering (TKDE), 15(2): 474-488, March/April 2003. [pdf]
27. J. Xu, D. L. Lee, and B. Li. "On Bandwidth Allocation for Data Dissemination in Cellular Mobile Networks." ACM Journal of Wireless Networks (WINET), 9(2): 103-116, March 2003. [pdf]
28. B. Zheng, J. Xu, and D. L. Lee. "Cache Invalidation and Replacement Policies for Location-Dependent Data in Mobile Environments." IEEE Transactions on Computers (TC), 51(10): 1141-1153, Oct. 2002. [pdf]
29. J. Xu, B. Li, and D. L. Lee. "Placement Problems for Transparent Data Replication Proxy Services." IEEE Journal on Selected Areas in Communications (JSAC), Special Issue on Internet Proxy Services, 20(7): 1383-1398, Sep. 2002. [pdf]
30. D. L. Lee, W.-C. Lee, J. Xu, and B. Zheng. "Data Management in Location-Dependent Information Services." IEEE Pervasive Computing, 1(3): 65-72, July-September 2002. [pdf]

1. H. Hu, J. Xu, C. Ren and B. Choi. "Processing Private Queries over Untrusted Data Cloud through Privacy Homomorphism." Proc. the 27th IEEE International Conference on Data Engineering (ICDE '11), Hannover, Germany, 2011.
2. Y. Peng, B. Choi and J. Xu. "Selectivity Estimation of Twig Queries on Cyclic Graphs." Proc. the 27th IEEE International Conference on Data Engineering (ICDE '11), Hannover, Germany, 2011.
3. Y. Li, J. Xu, B. Choi, and H. Hu. "StableBuffer: Optimizing Write Performance for DBMS Applications on Flash Devices." Proc. the 19th ACM International Conference on Information and Knowledge Management (CIKM '10), Toronto, Canada, October 2010. [pdf]
4. S. T. On, Y. Li, B. He, M. Wu, Q. Luo, and J. Xu. "FD-Buffer: A Buffer Manager for Databases on Flash Disks." Proc. the 19th ACM International Conference on Information and Knowledge Management (CIKM '10), Toronto, Canada, October, 2010. (Short paper)
5. X. Liu, M. Ye, J. Xu, Y. Tian, and W.-C. Lee. "k-Selection Query over Uncertain Data." Proc. the 15th International Conference on Database Systems for Advanced Applications (DASFAA '10), Tsukuba, Japan, April 2010. (Best Student Paper Award Runner-up) [pdf]
6. X. Pan, X. Meng, and J. Xu. "Distortion-based Anonymity for Continuous Queries in Location-Based Mobile Services." Proc. the 17th ACM SIGSPATIAL Int'l Conference on Advances in Geographic Information Systems (ACM GIS '09), Seattle, USA, November 2009. [pdf]
7. Y. Tang, J. Xu, S. Zhou, and W.-C. Lee. "m-LIGHT: Indexing Multi-Dimensional Data over DHTs." Proc. the 29th IEEE Int'l Conference on Distributed Computing Systems (ICDCS '09), Montreal, Quebec, Canada, May 2009. [pdf]
8. Y. Li, S. T. On, J. Xu, B. Choi, and H. Hu. "DigestJoin: Exploiting Fast Random Reads for Flash-based Joins." Proc. the 10th International Conference on Mobile Data Management (MDM '09 ), Taipei, Taiwan, May 2009. [pdf]
9. S. T. On, H. Hu, Y. Li, and J. Xu. "Lazy-Update B+-Tree for Flash Devices." Proc. the 10th International Conference on Mobile Data Management (MDM '09 ), Taipei, Taiwan, May 2009. [pdf]
10. H. Hu and J. Xu. "Non-Exposure Location Anonymity." Proc. IEEE 25th International Conference on Data Engineering (ICDE '09 ), Shanghai, China, March 2009. [pdf]
11. D. Wang, J. Xu, J.-C. Liu, and F. Wang. "Mobile Filtering for Error-Bounded Data Collection in Sensor Networks." Proc. the 28th IEEE Int. Conf. on Distributed Computing Systems (ICDCS '08), Beijing, China, June 2008. [pdf]
12. D. Wang, J. Xu, J.-C. Liu, and F. Wang. "Mobile Filter: Exploring Migration of Filters for Error-Bounded Data Collection in Sensor Networks." ICDE '08, Cancun, Mexico, April 2008. (Poster Paper) [pdf]
13. Y. Xu, J. Xu, and W.-C. Lee. "Analysis of a Loss-Resilient Proactive Data Transmission Protocol in Wireless Sensor Networks." Proc. the 26th IEEE INFOCOM '07, Anchorage, Alaska, USA, May 2007. [pdf]
14. J. Du, J. Xu, X. Tang, and H. Hu. "iPDA: Supporting Privacy-Preserving Location-Based Mobile Services." Proc. the 8th Int. Conf. on Mobile Data Management (MDM '07), Mannheim, Germany, May 2007. (Demo) [pdf]
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15. C. K. Lee, W.-C. Lee, J. Winter, B. Zheng, and J. Xu. "CS Cache Engine: Data Access Accelerator for Location-Based Services in Mobile Environments." Proc. the 25th ACM SIGMOD Int. Conf. on Management of Data (SIGMOD '06), Chicago, IL, June 2006. (Demo) [pdf]
16. M. Wu, J. Xu, and X. Tang. "Processing Precision-Constrained Queries in Wireless Sensor Networks." Proc. the 7th Int. Conf. on Mobile Data Management (MDM '06), Nara, Japan, May 2006. [pdf]
17. X. Tang and J. Xu. "Extending Network Lifetime for Precision-Constrained Data Aggregation in Wireless Sensor Networks." Proc. the 25th IEEE INFOCOM '06, Barcelona, Spain, April 2006. [pdf]
18. Y. Xu, W.-C. Lee, J. Xu, and G. Mitchel. "Processing Window Queries in Wireless Sensor Networks." Proc. the 22nd IEEE Int. Conf. on Data Engineering (ICDE '06), Atlanta, GA, April 2006. [pdf]
19. M. Wu, J. Xu, X. Tang, and W.-C. Lee. "Monitoring Top-k Query in Wireless Sensor Networks." Proc. the 22nd IEEE Int. Conf. on Data Engineering (ICDE '06), Atlanta, GA, April 2006. (Poster Paper) [pdf]
20. H. Hu, D. L. Lee, and J. Xu. "Fast Nearest Neighbor Search on Road Networks." Proc. the 10th International Conference on Extending Database Technology (EDBT '06), Munich, Germany, March 2006. [pdf]
21. C. K. Lee, W.-C. Lee, B. Zheng, and J. Xu. "Caching Complementary Space for Location-Based Services." Proc. the 10th International Conference on Extending Database Technology (EDBT '06), Munich, Germany, March 2006. [pdf]
22. J. Xu, X. Tang, and W-C. Lee. "EASE: An Energy-Efficient In-Network Storage Scheme for Object Tracking in Sensor Networks." Proc. the 2nd IEEE Conf. on Sensor and Ad Hoc Communications and Networks (SECON '05), Santa Clara, CA, September 2005. [pdf]
23. H. Hu, J. Xu, and D. L. Lee. "A Generic Framework for Monitoring Continuous Spatial Queries over Moving Objects." Proc. the ACM SIGMOD Conference (SIGMOD '05), Baltimore, MD, June 2005. [pdf]
24. H. Hu, J. Xu, W. S. Wong, B. Zheng, D. L. Lee, and W.-C. Lee. "Proactive Caching for Spatial Queries in Mobile Environments." Proc. the 21th IEEE Int. Conf. on Data Engineering (ICDE '05), Tokyo, Japan, April 2005. [pdf]
25. J. Xu, W.-C. Lee, and X. Tang. "Exponential Index: A Parameterized Distributed Indexing Scheme for Data on Air." Proc. the 2nd ACM/USENIX Int. Conf. on Mobile Systems, Applications, and Services (MobiSys '04), Boston, MA, June 2004, pp. 153 - 164. [pdf]
26. B. Zheng, J. Xu, W.-C. Lee, and D. L. Lee. "Energy-Conserving Air Indexes for Nearest Neighbor Search." Proc. the 9th Int. Conf. on Extending Database Technology (EDBT '04), Heraklion, Crete, Greece, March 2004, Springer-Verlag LNCS, vol. 2992, pp. 48-66. [pdf]
27. X. Tang and J. Xu. "On Replica Placement for QoS-Aware Content Distribution." Proc. the 23rd IEEE INFOCOM '04, Hong Kong, March 2004, pp. 806-815. [pdf]
28. J. Liu, X. Chu, and J. Xu. "Proxy Cache Management for Fine-Grained Scalable Video Streaming." Proc. the 23rd IEEE INFOCOM '04, Hong Kong, March 2004, pp. 1490-1500. [pdf]
29. J. Xu, B. Zheng, W.-C. Lee, and D. L. Lee. "Energy Efficient Index for Querying Location-Dependent Data in Mobile Broadcast Environments." Proc. the 19th IEEE Int. Conf. on Data Engineering (ICDE '03), Bangalore, India, March 2003, pp. 239-250. [pdf]

1. J. Xu, H. Hu, X. Tang, and B. Zheng. "Mobile Cache Management." Wireless Information Highways, D. Katsaros, A. Nanopoulos, and Y. Manolopoulos, Eds., Idea Group Publishing, 2005. (Invited book chapter)
2. J. Xu and J. Liu. "Broadcast Scheduling Algorithms for Wireless Data Dissemination." Design and Analysis of Wireless Networks, Chapter 8, Y. Pan and Y. Xiao, Eds., Nova Science Publishers, ISBN: 1-59454-186-8, 2004. (Invited book chapter)
3. J. Xu, D. L. Lee, Q. Hu, and W.-C. Lee. "Data Broadcast."  Handbook of Wireless Networks and Mobile Computing, Chapter 11, Ivan Stojmenovic, Ed., New York: John Wiley & Sons, ISBN 0-471-41902-8, Jan. 2002, pp. 243-265. (Invited book chapter) [pdf]
4. J. Xu, B. Zheng, M. Zhu, and D. L. Lee. "Research Challenges in Information Access and Dissemination in a Mobile Environment." Proc. Pan-Yellow-Sea International Workshop on Information Technologies for Network Era (PYIWIT '02), Saga, Japan, March, 2002, pp. 1-8. (Invited paper) [ps]

• X. Tang, J. Xu, and S. T. Chanson. "Web Content Delivery." Springer, ISBN: 0-387-24356-9, August 2005. (Table of Content)

• "Data Access Techniques for Location-Based Services." (with B. Zheng and W. C. Lee). The 7th Int. Conf. on Mobile Data Management (MDM '06), Nara, Japan, May 9 - 13, 2006.
• "Data Management in Location-Dependent Information Services." (with W. C. Lee and B. Zheng). The 20th IEEE Int. Conf. on Data Engineering (ICDE '04), Boston, MA, March 30 - April 2, 2004.

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