Nikolaos E. Panagiotou

Office A23, Department of Informatics and Telecommunications, National and Kapodistrian University of Athens, University Campus, Ilissia, 15703, Athens, Greece · n.panagiotou <AT>

My name is Nikolaos Panagiotou and I received the Ph.D degree from the Department of Informatics and Telecommunications of the University of Athens under the supervision of Prof. D. Gunopulos. Previously, I received my MSc. degree in Artificial Intelligence from the University of Edinburgh and my BSc degree from the Department of Informatics and Telecommunications of the University of Athens. During my Ph.D research I mostly focus on real-time analysis on high volume data streams with particular emphasis on text and sensor streams including news and social media content. I am also a member of the KDDLAB research group at the University of Athens where I participate on EU research projects. I also held a software engineer position at KORIMVOS S.A. until 2016 where I was involved in various projects and technologies. During my BSc. studies I was a voluntary member of at Network Operations Center at the University of Athens. Full CV available here.

My Current research interests include:
  • Text Mining: event detection, first story detection, open information extraction
  • IoT/ Smart-Cities : sensor analysis, heterogeneous sensor aggregation, real-time visualization
  • Spatio-temporal Analysis: Congested road-segments , travel time estimation, OSM


Research Engineer

Depratment of Informatics and Telecommunications, University of Athens

Involved in the INSIGHT and VaVeL EU funded projects. For the INSIGHT project, actively participated in the implementation of the real-time analysis modules and of the visualization engine for the smart city of Dublin. For the VaVeL project, I participated in the design of the integration scheme. In addition, I developed real-time analysis modules using the available spatio-temporal data and I was one of the main developers of the visualization dashboard. Video demonstrations of the INSIGHT and of the VaVeL dashboards are available online.

March 2014 - Present

Part-Time Software Engineer


Participated in the ARETEUS project and developed a smart card application for the National Center of Diabetes. Utilized the technology of Java-card and familiarized with developing software suitable for devices with very low computing resources. In addition, involved in a plagiarism detection system for identifying plagiarized text from external sources (e.g., Wikipedia) for project proposals written in the Greek language.

February 2014 - February 2016

Soldier, Sapper, Minesweeper

Hellenic Army

Compulsory military service under the Hellenic Army. Specialization of Minesweeper and Sapper. Received training specialized on land minefield clearing and explosive disposal as well as the general military training.Member of the Information Services Helpdesk providing solutions to officer en-quires and repairing defective computing equipment.

Oct 2011 - July 2012

Junior Software Engineer


Responsibilities included the content development for various Hellenic high school and primary school courses, for the e-learning platform Digital School. Participated in various project proposals related to e-learning, responsible for open source solutions that could be integrated with asynchronous collaborative e-learning platforms.

February 2011 - September 2011


Depratment of Informatics and Telecommunications, Network Operations Center, University of Athens

Supporting the university members regarding network connectivity issues. Creating the email accounts for the post-graduate students.

September 2009 - December 2009


Ph.D Candidate in Real-time Data Analysis in Massive Streams and Social Media

Department of Informatics and Telecommunications, University of Athens
March 2014 - Present

MSc. with Distinction in Artificial Intelligence, Learning from Data

School of Informatics, University of Edinburgh
September 2012 - August 2013

BSc. in Informatics and Telecommunications

Department of Informatics and Telecommunications, University of Athens
September 2007 - September 2011



  • Panagiotou, N. E., Akkaya, C., Tsioutsiouliklis, K., Kalogeraki, V., & Gunopulos, D. (2020). A General Framework for First Story Detection Utilizing Entities and their Relations. IEEE Transactions on Knowledge and Data Engineering.


  • Nikolaos Zygouras, Nikolaos Panagiotou, Yang Li, Dimitrios Gunopulos, Leonidas J. Guibas: HTTE: A Hybrid Technique For Travel Time Estimation In Sparse Data Environments. SIGSPATIAL/GIS 2019: 99-108


  • Avigdor Gal, Dimitrios Gunopulos, Nikolaos Panagiotou, Nicolo Rivetti, Arik Senderovich, Nikolas Zygouras: REMI: A framework of reusable elements for mining heterogeneous data with missing information - A Tale of Congestion in Two Smart Cities. J. Intell. Inf. Syst. 51(2): 367-388 (2018)
  • Dimitrios Tomaras, Vana Kalogeraki, Nikolas Zvgouras, Nikolaos Panagiotou, Dimitrios Gunopulos: Evaluating the Health State of Urban Areas Using Multi-source Heterogeneous Data. WOWMOM 2018: 14-22


  • Avigdor Gal, Nicolo Rivetti, Arik Senderovich, Dimitrios Gunopulos, Ioannis Katakis, Nikolaos Panagiotou, Vana Kalogeraki: REMI, Reusable Elements for Multi-Level Information Availability: Demo. DEBS 2017: 323-326


  • Nikolaos Panagiotou, Ioannis Katakis, Dimitrios Gunopulos, Vana Kalogeraki, Elizabeth Daly, Jia Yuan Yu, Brendan O'Brien: Mining hidden constrained streams in practice: Informed search in dynamic filter spaces. ASONAM 2016: 571-578
  • Nikolaos Panagiotou, Ioannis Katakis, Dimitrios Gunopulos: Detecting Events in Online Social Networks: Definitions, Trends and Challenges. Solving Large Scale Learning Tasks 2016: 42-84
  • Nikolaos Panagiotou, Cem Akkaya, Kostas Tsioutsiouliklis, Vana Kalogeraki, Dimitrios Gunopulos: First Story Detection using Entities and Relations. COLING 2016: 3237-3244
  • Nikos Zacheilas, Nikolas Zygouras, Nikolaos Panagiotou, Vana Kalogeraki, Dimitrios Gunopulos: Dynamic Load Balancing Techniques for Distributed Complex Event Processing Systems. DAIS 2016: 174-188
  • Nikolaos Panagiotou, Nikolas Zygouras, Ioannis Katakis, Dimitrios Gunopulos, Nikos Zacheilas, Ioannis Boutsis, Vana Kalogeraki, Stephen Lynch, Brendan O'Brien, Dermot Kinane, Jakub Marecek, Jia Yuan Yu, Rudi Verago, Elizabeth Daly, Nico Piatkowski, Thomas Liebig, Christian Bockermann, Katharina Morik, François Schnitzler, Matthias Weidlich, Avigdor Gal, Shie Mannor, Hendrik Stange, Werner Halft, Gennady L. Andrienko: INSIGHT: Dynamic Traffic Management Using Heterogeneous Urban Data. ECML/PKDD (3) 2016: 22-26
  • Nikolaos Panagiotou, Nikolas Zygouras, Ioannis Katakis, Dimitrios Gunopulos, Nikos Zacheilas, Ioannis Boutsis, Vana Kalogeraki, Stephen Lynch, Brendan O'Brien: Intelligent Urban Data Monitoring for Smart Cities. ECML/PKDD (3) 2016: 177-192


  • Nikos Zacheilas, Vana Kalogeraki, Nikolaos Zygouras, Nikolaos Panagiotou, Dimitrios Gunopulos: Elastic complex event processing exploiting prediction. Big Data 2015: 213-222
  • Nikolaos Zygouras, Nikolaos Panagiotou, Nikos Zacheilas, Ioannis Boutsis, Vana Kalogeraki, Ioannis Katakis, Dimitrios Gunopulos:Towards Detection of Faulty Traffic Sensors in Real-Time. MUD@ICML 2015: 53-62

Toos/ Code/ Datasets/ Demos

News Monitor

Analyzing news in Real-Time.

Smart Attica Dashboard

Video presentation of the prototype of the Smart Attica system. This system is instantiated for the city of Athens.

VaVeL Dashboard

Video presentation of the smart city monitoring dashboard developed within the VaVeL project.

INSIGHT Dashboard

Video presentation of the smart city monitoring dashboard developed within the INSIGHT project.

COLING 2016 Paper

Dataset preprocessing tools and dataset annotation software available here.

ASONAM 2016 Paper

Supplementary paper material is available here.

Text Miner

Text mining library including text preprocessing tools, trend detection modules and nearest neighbor identification using locality sensitive hashing. Available here.