People

Researchers

Lauri Hella

Professor Emerita/Emeritus
Faculty of Information Technology and Communication Sciences
Tampere University
lauri.hella@tuni.fi

https://orcid.org/0000-0002-9117-8124

More information

About me

I am an emeritus professor of mathematics. My research areas are mathematical logic and logic in computer science.

Before retiring I was leading the Tampere Logic Group.

Research topics

Definability theory of generalized quantifiers

Ehrenfeucht-Fraisse games and formula size games, and their applications

Descriptive complexity theory: logical characterizations of complexity classes

Modal and first-order dependence logics and team semantics

Research fields

Mathematics, theoretical computer science

Selected publications

L. Hella: Definability hierarchies of generalized quantiers. Annals of Pure and Applied Logic 43 (1989): 235-271.

L. Hella: Logical hierarchies in PTIME. Information and Computation 129 (1996): 1-19.

L. Hella, L. Libkin, J. Nurmonen, and L. Wong: Logics with aggregate operators. Journal of the ACM 48 (2001): 880-907.

P. Galliani and L. Hella: Inclusion logic and fixed point logic. Proc. 22th Annual Conference the EACSL (CSL), 2013, pages 281-295.

L. Hella, M. Järvisalo, A. Kuusisto, J. Laurinharju, T. Lempiäinen, K. Luosto, J. Suomela, and J. Virtema: Weak models of distributed computing, with connections to modal logic. Distributed Computing 28(1) (2015): 31-53.

L. Hella and A. Kuusisto: Existential second-order logic and modal logic with quantified accessibility relations. Information and Computation 247 (2016): 217-234.

Own links

Tampere Logic Group

Latest publications

Descriptive complexity for distributed computing with circuits

Ahvonen, V., Heiman, D., Hella, L. & Kuusisto, A., tammik. 2025, (E-pub ahead of print) julkaisussa: JOURNAL OF LOGIC AND COMPUTATION. exae087.

Tutkimustuotos: Artikkeli › Tieteellinen › vertaisarvioitu

Defining long words succinctly in FO and MSO

Hella, L. & Vilander, M., 28 marrask. 2024, julkaisussa: Computability. 13, 3-4, s. 377-398 22 Sivumäärä

Tutkimustuotos: Artikkeli › Tieteellinen › vertaisarvioitu

Dimension in team semantics

Hella, L., Luosto, K. & Väänänen, J., 2024, (E-pub ahead of print) julkaisussa: MATHEMATICAL STRUCTURES IN COMPUTER SCIENCE.

Tutkimustuotos: Artikkeli › Tieteellinen › vertaisarvioitu

Game characterizations for the number of quantifiers

Hella, L. & Luosto, K., 2024, (E-pub ahead of print) julkaisussa: MATHEMATICAL STRUCTURES IN COMPUTER SCIENCE.

Tutkimustuotos: Artikkeli › Tieteellinen › vertaisarvioitu

Quantifiers Closed Under Partial Polymorphisms

Dawar, A. & Hella, L., helmik. 2024, 32nd EACSL Annual Conference on Computer Science Logic, CSL 2024. Murano, A. & Silva, A. (toim.). Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 23. (Leibniz International Proceedings in Informatics, LIPIcs; Vuosikerta 288).

Tutkimustuotos: Konferenssiartikkeli › Tieteellinen › vertaisarvioitu

A Completeness Proof for a Regular Predicate Logic with Undefined Truth Value

Valmari, A. & Hella, L., 2023, julkaisussa: NOTRE DAME JOURNAL OF FORMAL LOGIC. 64, 1, s. 61-93 33 Sivumäärä

Tutkimustuotos: Artikkeli › Tieteellinen › vertaisarvioitu

Descriptive Complexity for Distributed Computing with Circuits

Ahvonen, V., Heiman, D., Hella, L. & Kuusisto, A., elok. 2023, 48th International Symposium on Mathematical Foundations of Computer Science, MFCS 2023. Leroux, J., Lombardy, S. & Peleg, D. (toim.). Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 9. (Leibniz International Proceedings in Informatics, LIPIcs; Vuosikerta 272).

Tutkimustuotos: Konferenssiartikkeli › Tieteellinen › vertaisarvioitu

The Expressive Power of CSP-Quantifiers

Hella, L., 1 helmik. 2023, 31st EACSL Annual Conference on Computer Science Logic, CSL 2023. Klin, B. & Pimentel, E. (toim.). Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 25. (Leibniz International Proceedings in Informatics; Vuosikerta 252).

Tutkimustuotos: Konferenssiartikkeli › Tieteellinen › vertaisarvioitu

Bounded game-theoretic semantics for modal mu-calculus

Hella, L., Kuusisto, A. & Rönnholm, R., 2022, julkaisussa: Information and Computation. 289, B, 19 Sivumäärä, 104882.

Tutkimustuotos: Artikkeli › Tieteellinen › vertaisarvioitu

Complexity thresholds in inclusion logic

Hannula, M. & Hella, L., 2022, julkaisussa: Information and Computation. 287, 104759.

Tutkimustuotos: Artikkeli › Tieteellinen › vertaisarvioitu

Tomi Janhunen

Professor
Computer Science
Faculty of Information Technology and Communication Sciences
Tampere University
+358503182250
tomi.janhunen@tuni.fi

https://orcid.org/0000-0002-2029-7708

More information

Field of expertise

Artificial Intelligence, Knowledge Representation and Reasoning, Logic Programming, Answer Set Programming and Optimization, Theoretical Computer Science

Funding

Main positions of trust

Selected publications

Latest publications

Automating Cybersecurity Compliance in DevSecOps with Open Information Model for Security as Code

Haverinen, H., Janhunen, T., Päivärinta, T., Lempinen, S., Kaartinen, S. & Merilä, S., 22 lokak. 2024, Proceedings of 4th Eclipse Security, AI, Architecture and Modelling Conference on Data Spaces, eSAAM 2024. ACM, s. 93-102 10 Sivumäärä

Tutkimustuotos: Konferenssiartikkeli › Tieteellinen › vertaisarvioitu

Capturing (Optimal) Relaxed Plans with Stable and Supported Models of Logic Programs (Extended Abstract)

Rankooh, M. F. & Janhunen, T., 2024, Proceedings of the 33rd International Joint Conference on Artificial Intelligence, IJCAI 2024. Larson, K. (toim.). International Joint Conferences on Artificial Intelligence, s. 8399-8404 6 Sivumäärä (IJCAI International Joint Conference on Artificial Intelligence).

Tutkimustuotos: Konferenssiartikkeli › Tieteellinen › vertaisarvioitu

Improved Encodings of Acyclicity for Translating Answer Set Programming into Integer Programming

Rankooh, M. F. & Janhunen, T., 2024, Proceedings of the 33rd International Joint Conference on Artificial Intelligence, IJCAI 2024. Larson, K. (toim.). International Joint Conferences on Artificial Intelligence, s. 3369-3376 8 Sivumäärä (IJCAI International Joint Conference on Artificial Intelligence).

Tutkimustuotos: Konferenssiartikkeli › Tieteellinen › vertaisarvioitu

Integrating Competencies into Preventive Maintenance Scheduling with Answer Set Optimization

Yli-Jyrä, A., Ikävalko, H. & Janhunen, T., 2024, Foundations of Information and Knowledge Systems: 13th International Symposium, FoIKS 2024, Sheffield, UK, April 8–11, 2024, Proceedings. Meier, A. & Ortiz, M. (toim.). Cham, Switzerland: Springer, s. 381-400 20 Sivumäärä (Lecture Notes in Computer Science; Vuosikerta 14589 LNCS).

Tutkimustuotos: Konferenssiartikkeli › Tieteellinen › vertaisarvioitu

Interpretable classifiers for tabular data via feature selection and discretization

Jaakkola, R., Janhunen, T., Kuusisto, A., Feyzbakhsh Rankooh, M. & Vilander, M., 2024, DAO-XAI 2024: Data meets Ontologies in Explainable AI 2024: Proceedings of the 4th International Workshop on Data meets Ontologies in Explainable AI co-located with the 27th European Conference on Artificial Intelligence (ECAI 2024) . CEUR-WS, 22 Sivumäärä (CEUR Workshop Proceedings; Vuosikerta 3833).

Tutkimustuotos: Konferenssiartikkeli › Tieteellinen › vertaisarvioitu

Plingo: A System for Probabilistic Reasoning in Answer Set Programming

Hahn, S., Janhunen, T., Kaminski, R., Romero, J., Rühling, N. & Schaub, T., 29 marrask. 2024, (E-pub ahead of print) julkaisussa: THEORY AND PRACTICE OF LOGIC PROGRAMMING.

Tutkimustuotos: Artikkeli › Tieteellinen › vertaisarvioitu

Toward Designing Ethically Acceptable AI Security Systems Through Agent Modeling

Hallamaa, J., Janhunen, T., Nummenmaa, J., Nummenmaa, T., Saariluoma, P. & Zimina, E., 2024, Smart Urban Safety and Security: Interdisciplinary Perspectives. Autero, A., de Moraes Batista Simão, M. & Karppi, I. (toim.). Palgrave Macmillan, s. 171-196

Tutkimustuotos: Luku › Tieteellinen › vertaisarvioitu

Capturing (Optimal) Relaxed Plans with Stable and Supported Models of Logic Programs

Feyzbakhsh Rankooh, M. & Janhunen, T., 2023, julkaisussa: THEORY AND PRACTICE OF LOGIC PROGRAMMING. 23, 4, s. 782-796

Tutkimustuotos: Artikkeli › Tieteellinen › vertaisarvioitu

Generalizing Level Ranking Constraints for Monotone and Convex Aggregates

Janhunen, T., syysk. 2023, Proceedings 39th International Conference on Logic Programming: EPTCS 385. Costantini, S., Pontelli, E., Russo, A., Toni, F., Calegari, R., D'Avila Garcez, A., Dodaro, C., Fabiano, F., Gaggl, S. & Mileo, A. (toim.). Open Publishing Association, s. 101-115 15 Sivumäärä 12. (Electronic Proceedings in Theoretical Computer Science; Vuosikerta 385).

Tutkimustuotos: Konferenssiartikkeli › Tieteellinen › vertaisarvioitu

Pruning Redundancy in Answer Set Optimization Applied to Preventive Maintenance Scheduling

Yli-Jyrä, A., Feyzbakhsh Rankooh, M. & Janhunen, T., 2023, Practical Aspects of Declarative Languages - 25th International Symposium, PADL 2023, Proceedings. Hanus, M. & Inclezan, D. (toim.). Springer, s. 279-294 16 Sivumäärä (Lecture Notes in Computer Science; Vuosikerta 13880).

Tutkimustuotos: Konferenssiartikkeli › Tieteellinen › vertaisarvioitu

Miikka Vilander

Postdoctoral Research Fellow
Faculty of Information Technology and Communication Sciences
Tampere University
miikka.vilander@tuni.fi

https://orcid.org/0000-0002-7301-939X

Kerkko Luosto

University Lecturer
alana matematiikka
Faculty of Information Technology and Communication Sciences
Tampere University
+358503185908
kerkko.luosto@tuni.fi

https://orcid.org/0009-0007-3911-766X

Veeti Ahvonen

Student, Doctoral Research
Faculty of Information Technology and Communication Sciences
Tampere University
veeti.ahvonen@tuni.fi

Available by email.
https://orcid.org/0009-0007-4819-0199

More information

About me

I am a PhD student and supervised by Antti Kuusisto and Lauri Hella. I graduated with a Master's degree in mathematics from Tampere University 2022. I sometimes work as a teaching assistant for mathematics courses.

Field of expertise

Mathematical logic
Descriptive complexity

Research topics

Mathematical logic

Descriptive complexity

Finite model theory

Funding

Mission statement

Selected publications

Latest publications

Descriptive complexity for distributed computing with circuits

Ahvonen, V., Heiman, D., Hella, L. & Kuusisto, A., tammik. 2025, (E-pub ahead of print) julkaisussa: JOURNAL OF LOGIC AND COMPUTATION. exae087.

Tutkimustuotos: Artikkeli › Tieteellinen › vertaisarvioitu

Descriptive Complexity for Neural Networks via Boolean Networks

Ahvonen, V., Heiman, D. & Kuusisto, A., 27 helmik. 2024, 32nd EACSL Annual Conference on Computer Science Logic (CSL 2024). Murano, A. & Silva, A. (toim.). Dagstuhl, Germany: Schloss Dagstuhl - Leibniz-Zentrum für Informatik, Vuosikerta 288. s. 9:1-9:22 22 Sivumäärä (Leibniz International Proceedings in Informatics (LIPIcs); Vuosikerta 288).

Tutkimustuotos: Konferenssiartikkeli › Tieteellinen › vertaisarvioitu

Damian Heiman

Grant Holder, Doctoral Research
Faculty of Information Technology and Communication Sciences
Tampere University
damian.heiman@tuni.fi

Reijo Jaakkola

Doctoral Researcher
Faculty of Information Technology and Communication Sciences
Tampere University
reijo.jaakkola@tuni.fi

https://orcid.org/0000-0003-4714-4637

Jonne Iso-Tuisku

Doctoral student
Department of Mathematics and Statistics
University of Helsinki

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