Mobile, Spatiotemporal and Social Database

Mobile and Ubiquitous Data Management

Portable and ubiquitous devices are changing our way of working, living and entertaining at an ever-increasing rate. So are they revealing the paradigm for future computing: autonomous devices interacting with servers, agents and peers. This new paradigm, however, poses tremendous challenges to our research community due to the large population, continuous movement, vulnerable network connectivity and bandwidth, scarce battery power, and limited screen size of these devices. While a huge body of research effort has been devoted to addressing the communication/networking aspect, especially at media access control and routing layer, less effort has been expended at the application layer to effectively manage resources and data. My research mostly falls in the category of context-aware data management, particularly in location-based services, which is one of the most distinguishing features in this new paradigm.

Selected Publications:

  • K. Huang, H. Hu, Q. Ye, K. Tian, B. Zheng, and X. Zhou. “TED: Towards Discovering Top-𝑘 Edge-Diversified Patterns in a Graph Database.” 2023 ACM SIGMOD International Conference on Management of Data, Seattle, Washington, USA, June 2023.
  • G. Zhang, J. Zhang, K. Liu, J. Guo, J. Lee, H. Hu, and V. Aggarwal. “DUASVS: A Mobile Data Saving Strategy in Short-form Video Streaming.” IEEE Transactions on Services Computing (TSC), Volume: 16, Issue: 2, 01 March 2023, pp. 1066 – 1078.
  • G. Zhang, K. Liu, H. Hu, V. Aggarwal, and Y. B. Lee. “Post-Streaming Wastage Analysis – A Data Wastage Aware Framework in Mobile Video Streaming.” IEEE Transactions on Mobile Computing (TMC), 22(1) January 2023, 389 – 401.
  • X. Pan, S. Nie, H. Hu, P. Yu, J. Guo, and L. Wu. “Reverse Nearest Neighbor Search in Semantic Trajectories for Location based Services.” IEEE Transactions on Services Computing (TSC), 15(2), pp 986-999, 2022.
  • L. Yao, Z. Chen, H. Hu, G. Wu, and B. Wu. “Privacy Preservation for Trajectory Publication Based on Differential Privacy.” ACM Transactions on Intelligent Systems and Technology (TIST), Vol. 13, No. 3, Article 42, April 2022.
  • G. Zhang, J. Zhang, Y. Liu, H. Hu, J. Lee, and V. Aggarwal. “Adaptive Video Streaming with Automatic Quality-of-Experience Optimization.” IEEE Transactions on Mobile Computing (TMC), accepted to appear, 2022.
  • L. Yao, Z. Chen, H. Hu, G. Wu, and B. Wu. “Sensitive attribute privacy preservation of trajectory data publishing based on l-diversity.” Distributed and Parallel Databases, November  2020.
  • L. Chen, J. Xu, X. Lin, C. S. Jensen, and H. Hu. “Answering Why-Not Spatial Keyword Top-k Queries via Keyword Adaption.” Proc. of the 32nd IEEE International Conference on Data Engineering (ICDE ’16), Helsinki, Finland, May 2016, pp 697-708.
  • X. Lin, J. Xu, and H. Hu. “Reverse Keyword Search for Spatio-Textual Top-k Queries in Location-Based Services.” IEEE Transactions on Knowledge and Data Engineering (TKDE), 27(11): 3056-3069, Nov. 2015.
  • L. Chen, X. Lin, H. Hu, C. S. Jensen, and J. Xu. “Answering Why-not Questions on Spatial Keyword Top-k Queries.” Proc. the 31th IEEE International Conference on Data Engineering (ICDE ’15), Seoul, Korea, April 2015.
  • Z. Chen, H. Hu, and J. Yu. “Privacy-Preserving Large-Scale Location Monitoring Using Bluetooth Low Energy.” Proc. of 11th IEEE International Conference on Mobile Ad-hoc and Sensor Networks (MSN 2015), Shenzhen, China, December 2015, pp 69-78.
  • Lu Wang, X. Meng, H. Hu, and J. Xu. “Bichromatic Reverse Nearest Neighbor Query without Information Leakage.” Proc. the 20th International Conference on Database Systems and Applications (DASFAA’15), Hanoi, Vietnam, April 2015.
  • X. Lin, J. Xu, and H. Hu. “Range-based Skyline Queries in Mobile Environments.” IEEE Transactions on Knowledge and Data Engineering (TKDE), 25(4): 835-849, April 2013.
  • H. Li, H. Hu, J. Xu. “Nearby Friend Alert: Location Anonymity in Mobile Geo-Social Networks”. IEEE Pervasive Computing, 12(4): 62-70, 2013.
  • H. Hu, Q. Chen, and J. Xu. “VERDICT: Privacy-Preserving Authentication of Range Queries in Location-based Services” Proc. of the 29th IEEE International Conference on Data Engineering (ICDE ’13), demo paper, 1312 – 1315.
  • Z. Huo, X. Meng, H. Hu, and Y. Huang. “You Can Walk Alone: Trajectory Privacy-preserving through Significant Stays Protection.” Proc. of the 17th International Conference on Database Systems for Advanced Applications (DASFAA ’12), pp. 351 – 366.
  • 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.
  • Chen, C. Lai, X. Meng, J. Xu, and H. Hu. “Clustering Moving Objects in Spatial Networks.” Proc. the 12th Int. Conf. on Database Systems for Advanced Applications (DASFAA ’07), Bangkok, Thailand, April 2007.
  • H. Hu and D. L. Lee. “Distance Indexing on Road Networks” Proc. of the 32th International Conference on Very Large Data Bases, Seoul, Korea, 2006, pp. 894-905.
  • H. Hu, D. L. Lee and J. Xu. “Fast Nearest Neighbor Search on Road Networks” Proc. of the 10th International Conference on Extending Database Technology, Munich, Germany, 2006, pp. 186-203.
  • H. Hu and D. L. Lee. “Range Nearest Neighbor Query.” IEEE Transactions on Data and Knowledge Engineering (TKDE), 18(1): 78-91, 2006.
  • H. Hu, J. Xu and D. L. Lee. “A Generic Framework for Monitoring Continuous Spatial Queries over Moving Objects” Proc. of the 24th ACM SIGMOD International Conference on Management of Data, Baltimore, Maryland, 2005, pp. 479-490.
  • H. Hu, J. Xu, W. S. Wong, B. Zheng and D. L. Lee. “Proactive Caching for Spatial Queries in Mobile Environments.” Proc. of the 21th IEEE International Conference on Data Engineering (ICDE ’05), Tokyo, Japan, pp. 403-414.

Externally Funded Projects:

  • Incognito Browsing of Spatial-Temporal Data Using Computational Private Information Retrieval (PI: RGC/GRF, 12200914, 2015-2018, HK$ 692,894)
  • Hybrid Geofencing Systems for Elderly and Child Care (PI: ITF/ITSP Tier 2, ITS/231/13FX, 2014-2016, HK$ $2,378,200)

Patents:

  • J. Xu and H. Hu. “A System and Method for Providing Proximity Information.” US Patent No. 9,351,116 B2, May 2016.

Social Network and Graph Data Management

Social network is a key Internet service for everyone. The efficient storage, retrieval, processing and analytics of data arising from social network pose great research challenge due to their heterogeneous and complex nature. In particular, many social network data are large graphs, for which efficient processing algorithms are yet to be investigated.

Selected Publications:

  • K. Huang, H. Hu, Q. Ye, K. Tian, B. Zheng, and X. Zhou. “TED: Towards Discovering Top-? Edge-Diversified Patterns in a Graph Database.” 2023 ACM SIGMOD International Conference on Management of Data, accepted to appear.
  • Q. Ye, H. Hu, M. H. Au, X. Meng, X. Xiao. “LF-GDPR: A Framework for Estimating Graph Metrics with Local Differential Privacy.” IEEE Transactions on Knowledge and Data Engineering (TKDE), Vol 34, Issue 10, pages 4905 – 4920, 2022.
  • K. Huang, Q. Ye, J. Zhao, X. Zhao, H. Hu, X. Zhou. “VINCENT: towards efficient exploratory subgraph search in graph databases.” Proceedings of the VLDB Endowment 15 (12), 3634-3637, 2022.
  • K. Huang, H. Hu, S. Zhou, Q. Ye, and J. Guan. “Privacy and Efficiency Guaranteed Social Subgraph Matching.” The VLDB Journal (VLDBJ), Volume 31, pages 581–602, 2022.
  • Q. Zhu, H. Hu, C. Xu, J. Xu, and W. Lee. “Geo-Social Group Queries with Minimum Acquaintance Constraints”, The VLDB Journal, 26(5), 709-727, October 2017 .
  • X. Lin, J. Xu, H. Hu and Z. Fan, “Reducing Uncertainty of Probabilistic Top-k Ranking via Pairwise Crowdsourcing”, IEEE Transactions on Knowledge and Data Engineering (TKDE), 29(10): 2290 – 2303, Oct. 2017.
  • Y. Li, R. Chen, J. Xu, Q. Huang, H. Hu, and B. Choi. “Geo-Social K-Cover Group Queries for Collaborative Spatial Computing.” IEEE Transactions on Knowledge and Data Engineering (TKDE), 27(10):2729 – 2742, October, 2015.
  • Z. Fan, B. Choi, Q. Chen, J. Xu, H. Hu and S. S. Bhowmick. “Structure-Preserving Subgraph Query Services.” IEEE Transactions on Knowledge and Data Engineering (TKDE), 27(08): 2275-2290, August, 2015.
  • Y. Peng, B. Choi, J. Xu, H. Hu, and S. S. Bhowmick. “Side-Effect Estimation: A Filtering Approach to the View Update Problem.” IEEE Transactions on Knowledge and Data Engineering (TKDE), 26(9): 2307 – 2322, August, 2014 .
  • J. Deng, B. Choi, J. Xu, H. Hu, and S. S. Bhowmick. “Incremental Maintenance of the Minimum Bisimulation of Cyclic Graphs.” IEEE Transactions on Knowledge and Data Engineering (TKDE), 25(11): 2536 – 2550, Nov 2013.