Journal Articles

  1. J. Li, W. Zhao, N. Ntarmos, Y. Cao, and P. Buneman, “Mitra: A framework for multi-instance graph traversal,” Proceedings of the VLDB Endowment (PVLDB), vol. 16, no. 10, pp. 2551–2564, 2023.
  2. I. Paun, Y. Moshfeghi, and N. Ntarmos, “White box: On the prediction of collaborative filtering recommendation systems’ performance,” ACM Transactions on Internet Technology, vol. 23, no. 1, pp. 1–29, 2023.
  3. J. Wang, Z. Liu, S. Ma, N. Ntarmos, and P. Triantafillou, “GC: A Graph Caching System for Subgraph/Supergraph Queries,” Proceedings of the VLDB Endowment (PVLDB), vol. 11, no. 12, pp. 2022–2025, 2018.
  4. F. Katsarou, N. Ntarmos, and P. Triantafillou, “Performance and Scalability of Indexed Subgraph Query Processing Methods,” Proceedings of the VLDB Endowment (PVLDB), vol. 8, no. 12, pp. 1566–1577, 2015.
  5. N. Ntarmos, I. Patlakas, and P. Triantafillou, “Rank join queries in NoSQL databases,” Proceedings of the VLDB Endowment (PVLDB), vol. 7, no. 7, pp. 493–504, 2014.
  6. S. Karavarsamis, N. Ntarmos, K. Blekas, and I. Pitas, “Detecting pornographic images by localizing skin ROIs,” International Journal of Digital Crime and Forensics (IJDCF), vol. 5, no. 1, pp. 39–53, 2013.
  7. T. Pitoura, N. Ntarmos, and P. Triantafillou, “Saturn: Range Queries, Load Balancing and Fault Tolerance in DHT Data Systems,” IEEE Transactions on Knowledge and Data Engineering (TKDE), vol. 24, no. 7, pp. 1313–1327, Jul. 2012.
  8. N. Ntarmos, P. Triantafillou, and G. Weikum, “Statistical Structures for Internet-Scale Data Management,” VLDB Journal (VLDBJ), vol. 18, no. 6, Dec. 2009.
  9. N. Ntarmos, P. Triantafillou, and G. Weikum, “Distributed hash sketches: Scalable, efficient, and accurate cardinality estimation for distributed multisets,” ACM Transactions on Computer Systems (TOCS), vol. 27, no. 1, pp. 2:1–2:53, 2009.
  10. P. Triantafillou, N. Ntarmos, and J. Yannakopoulos, “D.I.C.E.: A cache engine for e-content integration,” IEEE Internet Computing, vol. 8, no. 2, pp. 45–53, 2004.

Conference Papers

  1. W. Zhao, Y. Cao, P. Buneman, J. Li, and N. Ntarmos, “Vectorizing Distributed Graph Computations Made Automated,” in Proceedings of the ACM International Conference on Management of Data (SIGMOD).
  2. A. Katsarakis, V. Gavrielatos, and N. Ntarmos, “DLHT: A non-blocking resizable hashtable with fast deletes and memory awareness,” in Proceedings of the 33rd International Symposium on High-Performance Parallel and Distributed Computing (HPDC), 2024.
  3. M. Al-Anqoudi, M. Bikanga-Ada, S. McQuistin, N. Ntarmos, J. Parkinson, and Y. Moshfeghi, “Traditional vs non-traditional assessment activities as learning indicators of student learning: Teachers’ perceptions,” in Proceedings of the 2023 IEEE Conference on Learning with MOOCS (LWMOOCS), 2023.
  4. I. Paun, Y. Moshfeghi, and N. Ntarmos, “Are we there yet? Estimating Training Time for Recommendation Systems,” in Proceedings of the 1st Workshop on Machine Learning and Systems (EuroMLSys), 2021.
  5. C. Morgan, I. Paun, and N. Ntarmos, “Exploring Contextual Paradigms in Context-Aware Recommendations,” in Proceedings of the 4th IEEE Workshop on Human-in-the-Loop Methods and Future of Work in Big Data (HMData), 2020.
  6. I. Kyosev, I. Paun, Y. Moshfeghi, and N. Ntarmos, “Measuring Distances Among Graphs En Route To Graph Clustering,” in Proceedings of the 5th IEEE Workshop on Advances in High-Dimensional Big Data (AdHDBigData), 2020.
  7. A. Cahsai, C. S. Anagnostopoulos, N. Ntarmos, and P. Triantafillou, “Revisiting Exact kNN Query Processing with Probabilistic Data Space Transformations,” in Proceedings of the IEEE International Conference on Big Data (BigData) (Best Student Paper Award), 2018.
  8. I. Popescu, K. Portelli, C. Anagnostopoulos, and N. Ntarmos, “The Case For Graph-Based Reommendations,” in Proceedings of the IEEE International Conference on Big Data (BigData), 2017.
  9. A. Cahsai, N. Ntarmos, C. Anagnostopoulos, and P. Triantafillou, “Scaling k-Nearest Neighbors Queries (The right way),” in Proceedings of the 37th IEEE International Conference on Distributed Computing Systems (ICDCS), 2017.
  10. J. Wang, N. Ntarmos, and P. Triantafillou, “Ensuring Consistency in Graph Cache for Graph-Pattern Queries,” in Proceedings of the 6th International Workshop on Querying Graph Structured Data (GraphQ), 2017.
  11. J. Wang, N. Ntarmos, and P. Triantafillou, “GraphCache: A Caching System for Graph Queries,” in Proceedings of the 20th International Conference on Extending Database Technology (EDBT), 2017.
  12. F. Katsarou, N. Ntarmos, and P. Triantafillou, “Hybrid Algorithms for Subgraph Pattern Queries in Graph Databases,” in Proceedings of the IEEE International Conference on Big Data (BigData), 2017.
  13. F. Katsarou, N. Ntarmos, and P. Triantafillou, “Subgraph Querying with Parallel Use of Query Rewritings and Alternative Algorithms,” in Proceedings of the 20th International Conference on Extending Database Technology (EDBT), 2017.
  14. J. Wang, N. Ntarmos, and P. Triantafillou, “Indexing Query Graphs to Speed Up Graph Query Processing,” in Proceedings of the 19th International Conference on Extending Database Technology (EDBT), 2016, pp. 41–52.
  15. J. Wang, N. Ntarmos, and P. Triantafillou, “Towards a Subgraph/Supergraph Cached Query-Graph Index,” in Proceedings of the IEEE International Conference on Big Data (BigData), 2015, pp. 2919–2921.
  16. G. Sfakianakis, I. Patlakas, N. Ntarmos, and P. Triantafillou, “Interval indexing and querying on key-value cloud stores,” in Proceedings of the 29th IEEE International Conference on Data Engineering (ICDE), 2013, pp. 805–816.
  17. S. Karavarsamis, I. Pitas, and N. Ntarmos, “Recognizing pornographic images,” in Proceedings of Multimedia and Security Workshop (MM&Sec), 2012, pp. 105–108.
  18. A. Loupasakis, N. Ntarmos, and P. Triantafillou, “eXO: Decentralized autonomous scalable social networking,” in Proceedings of the 5th Biennial Conference on Innovative Data Systems Research, Conference Proceedings (CIDR), 2011, pp. 85–95.
  19. S. Karavarsamis, N. Ntarmos, and K. Blekas, “InFeRno: An Intelligent Framework for Recognizing Pornographic Web Pages,” in Proceedings of the European Conference on Machine Learning and Knowledge Discovery in Databases (ECML-PKDD), 2011, pp. 638–641.
  20. G. Weikum, N. Ntarmos, M. Spaniol, P. Triantafillou, A. Benczúr, S. Kirkpatrick, P. Rigaux, and M. Williamson, “Longitudinal analytics on Web archive data: It’s about time!,” in Proceedings of the 5th Biennial Conference on Innovative Data Systems Research (CIDR), 2011, pp. 199–202.
  21. C. Kaidos, A. Pasiopoulos, P. Triantafillou, and N. Ntarmos, “SNFS: The design and implementation of a social network file system,” in Proceedings of the 4th Workshop on Social Network Systems (SNS), 2011, pp. 5:1–5:6.
  22. G. Koloniari, N. Ntarmos, E. Pitoura, and D. Souravlias, “One is enough: Distributed filtering for duplicate elimination,” in Proceedings of the ACM International Conference on Information and Knowledge Management (CIKM), 2011, pp. 433–442.
  23. S. Michel, M. Bender, N. Ntarmos, P. Triantafillou, G. Weikum, and C. Zimmer, “Discovering and exploiting keyword and attribute-value co-occurrences to improve P2P routing indices,” in Proceedings of the ACM International Conference on Information and Knowledge Management (CIKM) (Best Interdisciplinary Paper Award), 2006.
  24. N. Ntarmos, P. Triantafillou, and G. Weikum, “Counting at Large: Efficient Cardinality Estimation in Internet-Scale Data Networks,” in Proceedings of the 22nd International Conference on Data Engineering (ICDE), 2006, p. 40.
  25. T. Pitoura, N. Ntarmos, and P. Triantafillou, “Replication, Load Balancing and Efficient Range Query Processing in DHTs,” in Proceedings of the 10th International Conference on Advances in Database Technology (EDBT), 2006, pp. 131–148.
  26. N. Ntarmos, T. Pitoura, and P. Triantafillou, “Range Query Optimization Leveraging Peer Heterogeneity in DHT Data Networks,” in Proceedings of the 3rd International Workshop on Databases, Information Systems, and Peer-to-Peer Computing (DBISP2P), 2005, pp. 111–122.
  27. N. Ntarmos and P. Triantafillou, “AESOP: Altruism-Endowed Self-organizing Peers,” in Proceedings of the 2nd International Workshop on Databases, Information Systems, and Peer-to-Peer Computing (DBISP2P), 2004.
  28. N. Ntarmos and P. Triantafillou, “SeAl: Managing accesses and data in peer-to-peer sharing networks,” in Proceedings of the 4th International Conference on Peer-to-Peer Computing (P2P), 2004, pp. 116–123.
  29. P. Triantafillou, N. Ntarmos, S. Nikoletseas, and P. Spirakis, “NanoPeer networks and P2P worlds,” in Proceedings of the Third International Conference on Peer-to-Peer Computing (P2P), 2003, pp. 40–46.
  30. P. Triantafillou, N. Ntarmos, and J. Yannakopoulos, “The HyperHotel application built over D.I.C.E. and Co.In.S,” in Proceedings of the Fourth International Conference on Web Information Systems Engineering (WISE), 2003, pp. 359–362.
  31. P. Triantafillou, N. Ntarmos, and J. Yannakopoulos, “D.I.C.E. and Co.In.S.: A data integration cache engine for a content integration system,” in Proceedings of the Fourth International Conference on Web Information Systems Engineering (WISE), 2003, pp. 339–342.
  32. P. Triantafillou, C. Xiruhaki, M. Koubarakis, and N. Ntarmos, “Towards High Performance Peer-to-Peer Content and Resource Sharing Systems,” in Proceedings of the ACM SIGMOD/VLDB Biennial Conference on Innovative Data Systems Research (CIDR), 2003.

Book Chapters

  1. I. Aekaterinidis, N. Ntarmos, T. Pitoura, and P. Triantafillou, “Towards Efficient Complex Data Management Services in Peer-to-Peer Networks,” in Global Data Management, R. Baldoni, G. Cortese, F. Davide, and A. Melpignano, Eds. IOS Press, 2006, pp. 324–341.

Technical Reports

  1. P. Donaldson, N. Ntarmos, and K. Portelli, “A Systematic Review of the Potential of Machine Learning and Data Science in Primary and Secondary Education,” The Royal Society, Discussion Paper, 2017.
  2. G. Sfakianakis, I. Patlakas, N. Ntarmos, and P. Triantafillou, “Interval Indexing and Querying on Key-Value Cloud Stores,” LAWA research project, Saarbrücken, Germany, WP3-7-21.09.2012, 2012.
  3. N. Ntarmos, I. Patlakas, G. Sfakianakis, and P. Triantafillou, “Rank Join Queries in Cloud Stores,” LAWA research project, Saarbrücken, Germany, WP3-6-21.09.2012, 2012.
  4. G. Sfakianakis, I. Patlakas, N. Ntarmos, and P. Triantafillou, “Interval Queries on the Cloud,” LAWA research project, Saarbrücken, Germany, WP3-2-22.09.2011, 2011.
  5. N. Ntarmos, I. Patlakas, and P. Triantafillou, “Decentralized Rank Join Queries,” LAWA research project, Saarbrücken, Germany, WP3-1-22.09.2011, 2011.
  6. A. Altanis, I. Patlakas, N. Ntarmos, and P. Triantafillou, “Joins and Selects on Clouds,” LAWA research project, Saarbrücken, Germany, WP3-3-22.09.2011, 2011.
  7. N. Ntarmos and P. Triantafillou, “Statistical Structures for Internet-Scale Query Optimization,” R.A. Computer Technology Institute, TR 2006/06/01, 2006.
  8. N. Ntarmos, T. Pitoura, and P. Triantafillou, “The RangeGuard: Range query optimization in peer-to-peer data networks,” R.A. Computer Technology Institute, TR 2004/12/04, 2004.
  9. T. Pitoura, N. Ntarmos, and P. Triantafillou, “HotRoD: Range query processing and load balancing in peer-to-peer data networks,” R.A. Computer Technology Institute, TR 2004/12/05, 2004.
  10. N. Ntarmos and P. Triantafillou, “sizeof() in P2P Networks: Hash Sketches over DHTs,” R.A. Computer Technology Institute, TR 2004/12/06, 2004.

Theses/Dissertations

  1. N. Ntarmos, “Development and Utilization of Novel Systems for Auditing, Accounting, and Computing of Global Characteristics and Properties of the Entities in Peer-to-Peer Networks,” PhD thesis, Dept. of Computer Engineering & Informatics, University of Patras, Greece, 2008.
  2. N. Ntarmos, “A Behavior Monitoring and Auditing System for Peer-to-Peer Networks,” Masters Thesis, Dept. of Computer Engineering & Informatics, University of Patras, Greece, 2004.
  3. N. Ntarmos, “An Internet Content Integration System: The Mediator and Wrappers,” Diploma Thesis, Dept. of Electronic & Computer Engineering, Technical University of Crete, Greece, 2002.