short biography
Pavlos Fafalios

Welcome to my personal Web page!

I am currently a postdoctoral research fellow at the Centre for Cultural Informatics of the Information Systems Laboratory (ISL) of FORTH-ICS (Greece), working as principal investigator of the ReKnow project (Marie Skłodowska-Curie Individual Fellowship, ID: 890861). In parallel, I am a visiting lecturer at the Department of Management Science and Technology of the Hellenic Mediterranean University, teaching Algorithms and Data Structures, E-commerce, and Software Technology.

I obtained my Engineer's Diploma in 2009 from the Department of Information and Communication Systems Engineering of University of the Aegean, and my MSc and PhD in 2012 and 2016, respectively, from the Computer Science Department of University of Crete (Greece).

My research interests fall in the areas of Information Retrieval, Semantic Web, Knowledge Representation, and Knowledge Engineering, with special focus on Cultural Informatics, Exploratory and Semantic Search, Semantic Data Management, and Linked Data. The results of my research have been published in more than 50 refereed research articles. I regularly participate to the programme committee of international conferences and workshops (including CIKM, ISWC and ESWC), and review papers for international journals (including the ACM Transactions on the Web and the Journal of the Association for Information Science and Technology).

You can find detailed information in my Curriculum Vitae (last update: April 2021) (ελληνική έκδοση - Ιούλιος 2020).

Latest news

• April 2021: Our paper "FAST CAT: Collaborative Data Entry and Curation for Semantic Interoperability in Digital Humanities" has been accepted for publication at the ACM Journal on Computing and Cultural Heritage.

• March 2021: Our paper "Exploiting stance hierarchies for cost-sensitive stance detection of Web documents" has been accepted for publication at the Journal of Intelligent Information Systems (Springer).

• March 2021: Our demo paper "ClaimLinker: Linking Text to a Knowledge Graph of Fact-checked Claims" has been accepted for publication at The Web Conference 2021.

• Jan 2021: Our interdisciplinary article "Digitizing, Curating and Visualizing Archival Sources of Maritime History: the case of ship logbooks of the 19th and 20th centuries" was published at the Drassana open access journal.

• Aug 2020: Our paper "Keyword Search over RDF: Is a Single Perspective Enough?" has been accepted at the Big Data and Cognitive Computing open access journal.

• Aug 2020: Our paper "TweetsCOV19 - A Knowledge Base of Semantically Annotated Tweets about the COVID-19 Pandemic" was accepted at the 29th ACM International Conference on Information and Knowledge Management (CIKM 2020).

• June 2020: I'm super excited to start working on the ReKnow project as a Marie Skłodowska-Curie fellow (MSCA IF).

older
publications
2021
P. Fafalios, K. Petrakis, G. Samaritakis, K. Doerr, A. Kritsotaki, Y. Tzitzikas, and M. Doerr
FAST CAT: Collaborative Data Entry and Curation for Semantic Interoperability in Digital Humanities
ACM Journal on Computing and Cultural Heritage (Accepted for publication in Apr'21), 2021.
A. Roy, P. Fafalios, A. Ekbal, X. Zhu, and S. Dietze
Exploiting stance hierarchies for cost-sensitive stance detection of Web documents
Journal of Intelligent Information Systems (Springer) (Accepted for publication in Mar'21), 2021.
E. Maliaroudakis, K. Boland, S. Dietze, K. Todorov, Y. Tzitzikas, and P. Fafalios
ClaimLinker: Linking Text to a Knowledge Graph of Fact-checked Claims (demo paper)
In Companion Proceedings of the Web Conference 2021 (ACM), Virtual Conference, April 19-23, 2021.
M. Doerr, P. Fafalios and A. Delis
Digital Seafaring: Digitising, Curating and Exploring Archival Sources of Maritime History,
ERCIM News 124, Research and Innovation, January 2021
2020
K. Petrakis, G. Samaritakis, T. Kalesios, E. G. Domingo, A. Delis, Y. Tzitzikas, M. Doerr, and P. Fafalios
Digitizing, Curating and Visualizing Archival Sources of Maritime History: the case of ship logbooks of the 19th and 20th centuries
Drassana: revista del Museu Marítim, (28), pp. 60-87, 2020.
D. Dimitrov, E. Baran, P. Fafalios, R. Yu, X. Zhu, M. Zloch, and S. Dietze
TweetsCOV19 - A Knowledge Base of Semantically Annotated Tweets about the COVID-19 Pandemic
29th ACM International Conference on Information and Knowledge Management (CIKM 2020), Virtual Conference, 2020.
C. Nikas, G. Kadilierakis, P. Fafalios, and Y. Tzitzikas
Keyword Search over RDF: Is a Single Perspective Enough?
Big Data and Cognitive Computing 4(3), 2020.
C. Nikas, P. Fafalios, and Y. Tzitzikas
Two-stage Semantic Answer Type Prediction for Question Answering using BERT and Class-Specificity Rewarding
SeMantic AnsweR Type prediction task (SMART) at ISWC 2020 Semantic Web Challenge, Virtual Conference, November 5, 2020.
G. Kadilierakis, P. Fafalios, P. Papadakos, and Y. Tzitzikas
Keyword search over RDF using document-centric information retrieval systems
17th Extended Semantic Web Conference (ESWC'20), Virtual Conference, June 2-4, 2020.
G. Kadilierakis, C. Nikas, P. Fafalios, P. Papadakos, and Y. Tzitzikas
Elas4RDF: Multi-perspective Triple-centered Keyword Search over RDF using Elasticsearch (demo paper)
17th Extended Semantic Web Conference (ESWC'20), Virtual Conference, June 2-4, 2020.
E. Ntoutsi, P. Fafalios, U. Gadiraju, V. Iosifidis, W. Nejdl, and others
Bias in data-driven artificial intelligence systems — An introductory survey
Wiley Interdisciplinary Reviews: Data Mining and Knowledge Discovery, 10(3), 2020.
R. S. João, P. Fafalios, and S. Dietze
Better together: an ensemble learner for combining the results of ready-made entity linking systems
35th ACM/SIGAPP Symposium on Applied Computing (SAC 2020), Virtual Conference, March 30 - April 3, 2020.
2019 show
2018 show
2017 show
2016 show
2015 show
2014 show
2013 show
2012 show
2011 show
projects involved top
ReKnow (2020 - now)

The ReKnow project (Grant agreement ID: 890861) aims to provide models and tools for helping researchers in empirical and descriptive sciences (like History) in better documenting, analysing and investigating research processes and data. Emphasis is given in maintaining the provenance of data and on the usability of the developed tools. More information at: https://reknow.ics.forth.gr/.

Role: Principal investigator, fellowship holder

RICONTRANS (2020 - now)

Project "SeaLiT – Seafaring Lives in Transition. Mediterranean Maritime Labour and Shipping during Globalization, 1850s-1920s", ERC Starting Grant (Νο. 714437). More information at: http://www.sealitproject.eu/

Role: Supervision and implementation of activities related to data management.

SeaLiT (2020 - now)

Project "RICONTRANS – Visual Culture, Piety and Propaganda: Transfer and Reception of Russian Religious Art in the Balkans and the Eastern Mediterranean (16th to early 20th Century)", ERC Consolidator Grant (No. 818791). More information at: https://ricontrans-project.eu/

Role: Supervision and implementation of activities related to data management.

CMBR (2019 - 2020)

The Centre for the study and sustainable exploitation of Marine Biological Resources (CMBR) is an integrative large-scale Greek Research Infrastructure (RI) of the National Roadmap for RI’s, dedicated to the advancement of Blue Growth through the study and sustainable exploitation of marine biological resources in the Eastern Mediterranean. For more information visit: http://cmbr.hcmr.gr/.

Role: Research and implementation of methods and tools for data integration and exploration.

Alexandria (2016 - 2019)

The ALEXANDRIA project (ERC Nr. 339233) aims to develop models, tools and techniques necessary to explore and analyze Web archives in a meaningful way. ALEXANDRIA will significantly advance semantic and time-based indexing for Web archives using human-compiled knowledge available on the Web, to efficiently index, retrieve and explore information about entities and events from the past. For more information visit: https://cordis.europa.eu/project/id/339233.

Role: Postdoctoral researcher; Research on methods for the semantic and entity-based exploration of Web Archives.

BlueBRIDGE (2015 - 2016)

European initiative funded under the H2020 framework to further develop and exploit the iMarine e-Infrastructure data services for an ecosystem approach to fisheries. For more information visit: https://cordis.europa.eu/project/id/675680.

Role: I extended the system X-Search for enabling the stochastic re-ranking of search results based on extracted entities. Moreover, I participated in the study of methods for quantifying the connectivity and evolution of a semantic warehouse.

iMarine (2012 - 2014)

iMarine (Data e-Infrastructure Initiative for Fisheries Management and Conservation of Marine Living Resources) is a European Commission funded project that kicked-off on 1st Nov 2011. It is an open and collaborative initiative that will establish a data infrastructure to support the Ecosystem Approach to fisheries management and conservation of marine living resources. For more information visit: https://cordis.europa.eu/project/id/283644.

Role: I designed and developed the system X-Search for the semantic exploration of search results, as well as the system X-Link for the extraction of entities and their further enrichment by exploiting Linked Data. Moreover, I participated in the development of the top-level ontology "MarineTLO" which allows describing and integrating marine data.

MUMIA (2012 - 2014)

Multilingual and Multifaceted Interactive Information Access (MUMIA), COST Action IC1002. The main objective of the Action is to coordinate and support the interaction and harmonization of high quality research at a European level in the field of multilingual and multifaceted interactive information access with a view to contribute to the development of next-generation search systems. For more information visit: https://www.cost.eu/actions/IC1002/.

Role: Member of the action, participation to working groups and management committee meetings, involved in WG4 (Semantic Search, Faceted Search and Visualization).

software top
SPARQL-LD
SPARQL-LD is an extension of SPARQL 1.1 that enables to directly fetch and query RDF data from heterogeneous sources via SERVICE calls. A distinctive characteristic of SPARQL-LD is that it allows querying and integrating even data in datasets returned by a portion of the query, i.e. identified at query-execution time. You can find more information (and try it) here. The source code is available on GitHub.
X-Search
X-Search is a web search service that reads the description of an underlying search source, and is able to query that source and analyze in various ways the returned results. X-Search also exploits the availability of semantic repositories. You can try X-Search (and find more information) here.
X-Link
X-Link is a fully configurable, Linked Data-based, named entity extraction tool. X-Link is capable to a) identify entities of interests (e.g. persons, locations, organizations, etc.) in any type of document, b) link the identified entities with semantic resources (i.e. with URIs), c) enrich the identified entities with semantic information (i.e. with properties and related entities), and d) infer whether and how the identified entities are associated. The main strength of X-Link is its extensive configurability: the user/administrator/developer can define and update the categories of entities that are interesting for the application at hand by exploiting one or more (on-line) Semantic Knowledge Bases. The user is also able to specify how to link the identified entities with semantic resources and how to enrich them with more information. You can find more information here.
IOS
IOS (Instant Overview Search) is a search-as-you-type functionality for web searching which provides an overview of the results as the user types his query letter-by-letter. You can try IOS (and find more information) here.
Theophrastus
Theophrastus is a system that supports the automatic annotation of web documents through entity mining and provides exploration services by exploiting Linked Open Data (LOD), in real-time and only when needed. Theophrastus was awarded the 1st prize in Blue Hackathon 2013. You can find more information (and try it) here.
Ithaca
Ithaca is a tool that reads open datasets, converts their data to RDF triples and loads the derived triples in a Virtuoso warehouse, offering thereby an API for directly exploiting the underlying data. Ithaca was awarded the 1st prize in Hack4Med 2014 (the HOMER project Hackathon). The source code is available on GitHub.
SPARQL Endpoint Browser
A web application for browsing the content of a SPARQL endpoint. You can try it here.
work/research experience top
June 2019 - now
June 2016 - May 2019
Postdoctoral Researcher
L3S Research Center, University of Hannover,
Hannover, Germany.
December 2010 - May 2016
Research assistant, software engineer, graduate fellow
Information Systems Laboratory (ISL),
Institute of Computer Science (ICS), Foundation for Research and Technology - Hellas (FORTH),
Heraklion, Greece.
my education top
October 2012 - May 2016
Ph. D.
Computer Science Department, University of Crete, Greece
Thesis Topic: "Exploiting Linked Data in Exploratory Search"
Thesis Supervisor: Ass. Prof. Yannis Tzitzikas
2010 - 2012
M. Sc. in Information Systems and E-commerce Technologies
Computer Science Department, University of Crete, Greece
Thesis Topic: "Indexes and Algorithms for Scalable and Flexible Instant Overview Search" [slides]
Thesis Supervisor: Ass. Prof. Yannis Tzitzikas
2003 - 2009
Dipl. Eng. in Information and Communication Systems Engineering
Department of Information and Communication Systems Engineering, School of Engineering, University of the Aegean, Greece
Thesis Topic: "Meta-Seeker: a Retroactive Algorithm for Personalizing Information from Multiple Web Search Services"
Thesis Supervisor: Ass. Prof. Ioannis Anagnostopoulos
awards and distinctions top
Fellowship from legacy "Maria Michael Manasaki" for the academic year 2014-2015. This fellowship is awarded once a year to the one or two best graduate students of Computer Science department of University of Crete.
1st prize for the "Best Homer Federation Open Data reuse app", 2nd prize for the "Most useful application for a public sector administration", and 1st prize for the “Best Solution for Crete”, in Hack4Med, the HOMER project Hackathon, held in the University of Crete, Department of Computer Science, 16-17 May 2014, Voutes Campus, Heraklion, Greece. Michalis Mountantonakis and I developed and presented the system "Ithaca: From Open Data to Linked Open Data".
1st prize in Blue Hackathon 2013, held in the Hellenic Centre for Marine Research (HCMR), 1-2 July 2013, Gournes, Heraklion, Greece. Panagiotis Papadakos and I developed and presented the system "Theophrastus: A Semantic Exploration Tool for Marine Taxonomists".
some personal information top

I was born in Chios, a beautiful island at the east of Greece, just five miles off the Asia Minor coast. In September 2003, I moved a few miles souther to Samos island where I lived five very beautiful years studying Information and Communication Systems Engineering. In November 2008 I joined the Greek Army Forces for one year to accomplish my military service. In February 2010 I started my graduate studies (MSc, PhD) in Crete island (Heraklion). In June 2016 I moved to Hannover (Lower Saxony, Germany) as a postdoctoral researcer, and in June 2019 I returned to Heraklion where I live until now.

In my free time, I like spending time with friends, watching and playing sports, traveling around, watching movies, reading books, and taking photos (you can find some here).

contact me top
email: fafalios[at]ics[dot]forth[dot]gr
gmail: fafalios.pavlos
skype: pavlos098
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