Evaluator for national funding agencies: Austria, Canada, Cyprus, Czech Republic, EU, Estonia, Georgia, Greece, Hong-Kong, Israel, Italy, Russia, Switzerland.
Evaluator for departmental promotions and hirings: University of Alberta (Canada), CYENS Centre of Excellence, Cyprus University of Technology, Frederick University (Cyprus), Charles University (Czech Republic), University of Aalborg (Denmark), Al al-Bayt University (Jordan), Lebanese American University (Lebanon), City University of New York (USA), Bilkent University (Turkey).
Evaluator for: the Department of Computer Science of the University of Aalborg, all the Departments of Computer Science of Lithuania.
Member of PhD examination committees at: University of Aalborg, University of Aarhus, University of Almeria, University of L'Aquila, University of Bozen-Bolzano, University of Coruna, École Polytechnique @ Paris, École Nationale Supérieure de Mécanique et d'Aérotechnique @ Poitiers, University of Milano, University of Pau and Pays Adour, Poznan University of Technology, University of Sao Paolo.
Key co-organizer of the following major conferences (ranked in A and B categories of CORE Portal): WISE'2021, SOFSEM'2020, WI'2019, IDEAS'2019, ICANN'2018, DASFAA'2018, TPDL'2017, ICCCI'2016, CAiSE'2014, ADBIS'2014, WISE'2014, WISE'2013, ICANN'2010, ADBIS'2009, ADBIS'2006, SSDBM'2004, SSTD'2003, ADBIS'2002.
Member of Editorial Boards: Digital (MDPI, Editor-in-Chief), Information Systems (Elsevier), The VLDB Journal (2011-2017, Springer), World Wide Web Journal (Springer), Data Science and Analytics (Springer), The Computer Journal (Oxford University Press), International Journal on Artificial Intelligence Tools (World Scientific), International Journal of Data Warehousing & Mining (IGI Global), International Journal of Knowledge-based Organizations (IGI Global), International Journal on Advances in Intelligent Systems (IARIA), Information & Data Management (Brazil), Cybernetics & Information Technologies (Bulgaria), Karbala International Journal of Modern Science (Iraq), International Journal of Web Research (Iran), Computer Science & Information Systems (Serbia), Information Sciences & Technologies (Slovakia).