Bernard Ries

bernard.ries@unifr.ch
+41 26 300 8333

International Relations

Digitalisation

Interdisciplinarity

Combinatorial optimization

Structural and algorithmic graph theory

Mathematical Modeling

Computational complexity

Vice-Rector
Rectorate

PER 21 bu. C324
Bd de P茅rolles 90
1700 Fribourg

PER 21, C324

+41 26 300 8333

Professor
Department of Informatics

PER 21 bu. C324
Bd de P茅rolles 90
1700 Fribourg

PER 21, C324

+41 26 300 8333

Biography

Biography: In 2007, I received my PhD in mathematics from Ecole Polytechnique Fédérale de Lausanne(CH). From 2008 to 2009, I was a Postdoctoral Research Fellow at Columbia University (US) in the Department of Industrial Engineering and Operations Research. In 2009-2010, I was appointed as Assistant Professor at the University of Warwick (UK) in the Center for Discrete Mathematics and its Applications (DIMAP) and the Warwick Business School (WBS). From September 2010 to July 2015, I was an Associate Professor at the Université Paris Dauphine (F) in the Computer Science and Mathematics Department. Currently I am a Professor at the 糖心Volg (CH), where I am heading the Decision Support & Operations Research Group together with Marino Widmer in the Department of Informatics. In 2022, I joined the project with some members of my team.

My main research interests are:

Structural and algorithmic graph theory
Combinatorial optimization
Computational complexity
Mathematical Modeling

Phd Students:

Nathanael Barrot: 2012 - 2015 (currently postdoc at RIKEN Research Center in Japan)
(co-supervisor: Jérôme Lang (Université Paris Dauphine))
: 2015 - 2020 (currently Assistant professor at Chalmers University of Technology, Sweden)
Vera Fischer: 2018 - 2023 (co-supervision with Meritxell Pacheco, currently at La Poste)
Felix Mann: 2019 -
Felicia Lucke: 2020 - 2024
Narmina Baghirova: 2020 - (co-supervision with David Schindl)
Elise Bangerter: 2023 - (co-supervision with Meritxell Pacheco)

Visiting PhD students:

Zakir Deniz (2017, Duzce University (Turkey))
Pierre Hauweele (2018, Université de Mons (Belgium))
Paloma Thomé de Lima (2018, University of Bergen (Norway))
Carolina Goncalvez (20021, 2022, University of Buenos Aires (Argentina))

Member of PhD committees:

Grégoire Cotté, Conservatoire National des Arts et Métiers, Paris, France (2016)
Vasileios Papapanagiotu, Università della Svizzera Italiana, Lugano, Switzerland (2018)
Gauvain Devillez, Université de Mons, Belgium (2022)
Nikolaos Melissinos, Université Paris Dauphine PSL, France (2022)
Valentin Bouquet, Conservatoire National des Arts et Métiers, Paris, France (2022)

Postdocs:

Diana Sasaki: 2014 - 2015 (now Professor at Universidade do Estado do Rio de Janeiro (Brazil))
Maria Pia Mazzoleni: August 2017 (now Docencia at Universidad Nacional La Plata (Argentina))
Andrea Munaro: February - June 2018 (now Assistant Professor at University of Parma (Italy))
Zakir Deniz: September - December 2019
Meritxell Pacheco: January 2021 - August 2021 (now Senior Researcher and Lecturer at 糖心Volg (CH))
Jérôme De Boeck: March 2022 - August 2023 (now Assistant Professor at HEC Liège, Belgium)
Nour Elhouda Tellache: 2024 -

Research and publications

Publications

137 publications

Bernard Ries, Carl Feghali, Felicia Lucke, Dani毛l Paulusma, Algorithmica (2025) | Journal article

David Schindl, Narmina Baghirova, Cl茅ment Dallard, Bernard Ries, Discrete Applied Mathematics (2024) | Journal article

Felicia Lucke, Dani毛l Paulusma, Bernard Ries, Theoretical Computer Science (2024) | Journal article

Felicia Lucke, Bernard Ries, Discrete Applied Mathematics (2024) | Journal article

Bernard Ries, Felicia Lucke, Dani毛l Paulusma, Algorithmica (2023) | Journal article

Galby, E. and Lima, P.T. and Mann, F. and Ries, B., Theoretical Computer Science (2023) | Journal article

Lucke, F. and Paulusma, D. and Ries, B. , arXiv (2023) | Other

Baghirova, N. and Dallard, C. and Ries, B. and Schindl, D. , Research Square (2023) | Other

Lucke, F. and Paulusma, D. and Ries, B., Leibniz International Proceedings in Informatics, LIPIcs: (2023) | Conference

Paulusma, D. and Ries, B. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2023) | Book

Lucke, F. and Paulusma, D. and Ries, B. , arXiv (2023) | Other

Feghali, Carl and Lucke, Felicia and Paulusma, Dani毛l and Ries, Bernard, Schloss Dagstuhl 鈥� Leibniz-Zentrum f眉r Informatik (2023) | Conference

Bonomo-Braberman, F. and Mazzoleni, M.P. and Rean, M.L. and Ries, B., Discrete Applied Mathematics (2022) | Journal article

Lucke, F. and Paulusma, D. and Ries, B. , arXiv (2022) | Other

Baghirova, N. and Dallard, C. and Ries, B. and Schindl, D. , arXiv (2022) | Other

Baghirova, N. and Gonzalez, C.L. and Ries, B. and Schindl, D. , arXiv (2022) | Other

Lucke, F. and Paulusma, D. and Ries, B. , arXiv (2022) | Other

Feghali, C. and Lucke, F. and Paulusma, D. and Ries, B. , arXiv (2022) | Other

Lucke, F. and Paulusma, D. and Ries, B., Leibniz International Proceedings in Informatics, LIPIcs: (2022) | Conference

Lucke, F. and Paulusma, D. and Ries, B. , arXiv (2022) | Other

Lucke, F. and Paulusma, D. and Ries, B., Theoretical Computer Science (2022) | Journal article

Baghirova, N. and Gonzalez, C.L. and Ries, B. and Schindl, D., Leibniz International Proceedings in Informatics, LIPIcs: (2022) | Conference

Feghali, C. and Lucke, F. and Paulusma, D. and Ries, B. , arXiv (2022) | Other

Nicolas Champseix and Esther Galby and Andrea Munaro and Bernard Ries, Discrete Applied Mathematics (2021) | Journal article

Galby, E. and Lima, P.T. and Mann, F. and Ries, B. , arXiv (2021) | Other

Galby, E. and Mann, F. and Ries, B., Discrete Applied Mathematics (2021) | Journal article

Galby, E. and Lima, P.T. and Ries, B., Discrete Mathematics (2021) | Journal article

Galby, E. and Mann, F. and Ries, B., Theoretical Computer Science (2021) | Journal article

Chen, B. and Martello, S. and Ries, B., Discrete Applied Mathematics (2021) | Journal article

Galby, E. and Lima, P.T. and Mann, F. and Ries, B. , arXiv (2021) | Other

Galby, E. and Munaro, A. and Ries, B., Theoretical Computer Science (2020) | Journal article

Galby, E. and Mann, F. and Ries, B. , arXiv (2020) | Other

Deniz, Z. and Nivelle, S. and Ries, B. and Schindl, D. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2020) | Book

Galby, E. and Mann, F. and Ries, B. , arXiv (2020) | Other

Paulusma, D. and Picouleau, C. and Ries, B., Discrete Applied Mathematics (2019) | Journal article

Hujdurovi?, A. and Milani?, M. and Ries, B., Discrete Mathematics (2019) | Journal article

Galby, E. and Lima, P.T. and Paulusma, D. and Ries, B., Information Processing Letters (2019) | Journal article

Crama, Y. and Gendron, B. and Ries, B., Discrete Applied Mathematics (2019) | Journal article

Galby, E. and Mazzoleni, M.P. and Ries, B., Discrete Applied Mathematics (2019) | Journal article

Galby, E. and Lima, P.T. and Ries, B., Leibniz International Proceedings in Informatics, LIPIcs: (2019) | Conference

Galby, E. and Lima, P.T. and Ries, B., Leibniz International Proceedings in Informatics, LIPIcs: (2019) | Conference

Hauweele, P. and Hertz, A. and M茅lot, H. and Ries, B. and Devillez, G., Discrete Applied Mathematics (2019) | Journal article

Galby, E. and Lima, P.T. and Ries, B. , arXiv (2019) | Other

Galby, E. and Paloma, T.L. and Ries, B. , arXiv (2019) | Other

Champseix, N. and Galby, E. and Munaro, A. and Ries, B. , arXiv (2019) | Other

Galby, E. and Lima, P.T. and Paulusma, D. and Ries, B. , arXiv (2019) | Other

Galby, E. and Lima, P.T. and Ries, B. , arXiv (2019) | Other

Champseix, N. and Galby, E. and Munaro, A. and Ries, B. , arXiv (2019) | Other

Galby, E. and Paloma, T.L. and Ries, B. , arXiv (2019) | Other

Galby, E. and Lima, P.T. and Paulusma, D. and Ries, B. , arXiv (2019) | Other

Alc贸n, L. and Bonomo, F. and Dur谩n, G. and Gutierrez, M. and Mazzoleni, M.P. and Ries, B. and Valencia-Pabon, M., Discrete Applied Mathematics (2018) | Journal article

AbouEisha, H. and Hussain, S. and Lozin, V. and Monnot, J. and Ries, B. and Zamaraev, V., Algorithmica (2018) | Journal article

Deniz, Z. and Galby, E. and Munaro, A. and Ries, B. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2018) | Book

Deniz, Z. and Nivelle, S. and Ries, B. and Schindl, D. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2018) | Book

Hertz, A. and Lozin, V. and Ries, B. and Zamaraev, V. and de Werra, D., Journal of Graph Theory (2018) | Journal article

Diner, 脰.Y. and Paulusma, D. and Picouleau, C. and Ries, B., Theoretical Computer Science (2018) | Journal article

Bonomo, F. and Mazzoleni, M.P. and Rean, M.L. and Ries, B. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2018) | Book

Hujdurovi?, A. and Milani?, M. and Ries, B., Discrete Mathematics (2018) | Journal article

Hujdurovic, A. and Kacar, U. and Milanic, M. and Ries, B. and Tomescu, A.I., IEEE/ACM Transactions on Computational Biology and Bioinformatics (2018) | Journal article

Champseix, N. and Galby, E. and Ries, B. , arXiv (2018) | Other

Galby, E. and Munaro, A. and Ries, B. , arXiv (2018) | Other

Galby, E. and Lima, P.T. and Paulusma, D. and Ries, B. , arXiv (2018) | Other

Galby, E. and Mazzoleni, M.P. and Ries, B. , arXiv (2018) | Other

Hujdurovi?, A. and Milani?, M. and Ries, B. , arXiv (2018) | Other

Bonomo, F. and Mazzoleni, M.P. and Rean, M.L. and Ries, B. , arXiv (2018) | Other

Deniz, Z. and Galby, E. and Munaro, A. and Ries, B. , arXiv (2018) | Other

Bonomo-Braberman, F. and Mazzoleni, M.P. and Rean, M.L. and Ries, B. , arXiv (2018) | Other

Galby, E. and Mazzoleni, M.P. and Ries, B. , arXiv (2018) | Other

Champseix, N. and Galby, E. and Ries, B. , arXiv (2018) | Other

Galby, E. and Lima, P.T. and Paulusma, D. and Ries, B. , arXiv (2018) | Other

Hujdurovi?, A. and Milani?, M. and Ries, B. , arXiv (2018) | Other

Galby, E. and Munaro, A. and Ries, B. , arXiv (2018) | Other

Deniz, Z. and Galby, E. and Munaro, A. and Ries, B. , arXiv (2018) | Other

Dantas, S. and Groshaus, M. and Guedes, A. and Machado, R.C.S. and Ries, B. and Sasaki, D., International Transactions in Operational Research (2017) | Journal article

Paulusma, D. and Picouleau, C. and Ries, B. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2017) | Book

Picouleau, C. and Paulusma, D. and Ries, B., Electronic Notes in Discrete Mathematics (2017) | Journal article

Diner, O.Y. and Paulusma, D. and Picouleau, C. and Ries, B. , arXiv (2017) | Other

Paulusma, D. and Picouleau, C. and Ries, B. , arXiv (2017) | Other

Diner, O.Y. and Paulusma, D. and Picouleau, C. and Ries, B. , arXiv (2017) | Other

Paulusma, D. and Picouleau, C. and Ries, B. , arXiv (2017) | Other

Demange, M. and Ekim, T. and Ries, B., Discrete Applied Mathematics (2016) | Journal article

Da Fonseca, G.D. and Ries, B. and Sasaki, D., Discrete Applied Mathematics (2016) | Journal article

Aboueisha, H. and Hussain, S. and Lozin, V. and Monnot, J. and Ries, B. and Zamaraev, V. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2016) | Book

Paulusma, D. and Picouleau, C. and Ries, B. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2016) | Book

Amanatidis, G. and Barrot, N. and Lang, J. and Markakis, E. and Ries, B., Proceedings of the International Joint Conference on Autonomous Agents and Multiagent Systems, AAMAS: (2015) | Conference

Demange, M. and Ekim, T. and Ries, B. and Tanasescu, C., European Journal of Operational Research (2015) | Journal article

Diner, 脰.Y. and Paulusma, D. and Picouleau, C. and Ries, B. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2015) | Book

Golovach, P.A. and Paulusma, D. and Ries, B., Discrete Applied Mathematics (2015) | Journal article

Alc贸n, L. and Bonomo, F. and Dur谩n, G. and Gutierrez, M. and P铆a Mazzoleni, M. and Ries, B. and Valencia-Pabon, M., Electronic Notes in Discrete Mathematics (2015) | Journal article

Hujdurovi茅, A. and Kacar, U. and Milani?, M. and Ries, B. and Tomescu, A.I. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2015) | Book

Barrot, N. and Lang, J. and Ries, B., Revue d鈥橧ntelligence Artificielle (2015) | Journal article

Lozin, V. and Monnot, J. and Ries, B., Journal of Discrete Algorithms (2015) | Journal article

Bazgan, C. and Bentz, C. and Picouleau, C. and Ries, B., Graphs and Combinatorics (2015) | Journal article

Martello, S. and Ries, B., Discrete Applied Mathematics (2015) | Journal article

Demange, M. and Monnot, J. and Pop, P. and Ries, B., Theoretical Computer Science (2014) | Journal article

Hertz, A. and Ries, B., Yugoslav Journal of Operations Research (2014) | Journal article

Aboueisha, H. and Hussain, S. and Lozin, V. and Monnot, J. and Ries, B. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2014) | Book

Cohen, E. and Golumbic, M.C. and Ries, B., Discrete Applied Mathematics (2014) | Journal article

Bonomo, F. and Cornaz, D. and Ekim, T. and Ries, B., Discrete Optimization (2013) | Journal article

Demange, M. and Lozin, V. and Picouleau, C. and Ries, B., Discrete Applied Mathematics (2013) | Journal article

Barrot, N. and Gourv猫s, L. and Lang, J. and Monnot, J. and Ries, B. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2013) | Book

Bazgan, C. and Chopin, M. and Ries, B., Discrete Applied Mathematics (2013) | Journal article

Lozin, V. and Monnot, J. and Ries, B. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2013) | Book

Dereniowski, D. and Kubiak, W. and Ries, B. and Zwols, Y., Networks (2013) | Journal article

Bentz, C. and Cornaz, D. and Ries, B., European Journal of Operational Research (2013) | Journal article

Golumbic, M.C. and Ries, B., Graphs and Combinatorics (2013) | Journal article

Golovach, P.A. and Paulusma, D. and Ries, B. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2012) | Book

Asinowski, A. and Ries, B., Discrete Mathematics (2012) | Journal article

Dabrowski, K.K. and Lozin, V. and Raman, R. and Ries, B., Discrete Mathematics (2012) | Journal article

Ries, B. and De Werra, D. and Zenklusen, R., Discrete Mathematics (2012) | Journal article

Birand, B. and Chudnovsky, M. and Ries, B. and Seymour, P. and Zussman, G. and Zwols, Y., IEEE/ACM Transactions on Networking (2012) | Journal article

Demange, M. and Monnot, J. and Pop, P. and Ries, B. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2012) | Book

Bentz, C. and Costa, M.-C. and Picouleau, C. and Ries, B. and De Werra, D., Journal of Discrete Algorithms (2012) | Journal article

Bentz, C. and Costa, M.-C. and de Werra, D. and Picouleau, C. and Ries, B., Electronic Notes in Discrete Mathematics (2011) | Journal article

Ries, B. and Zenklusen, R., European Journal of Operational Research (2011) | Journal article

Chudnovsky, M. and Ries, B. and Zwols, Y., Discrete Applied Mathematics (2011) | Journal article

Chudnovsky, M. and Ries, B. and Zwols, Y., Discrete Applied Mathematics (2011) | Journal article

Ekim, T. and Ries, B. and De Werra, D., Discrete Mathematics and Theoretical Computer Science (2010) | Journal article

Ries, B., Discrete Applied Mathematics (2010) | Journal article

Ries, B. and Bentz, C. and Picouleau, C. and de Werra, D. and Costa, M.-C. and Zenklusen, R., Discrete Mathematics (2010) | Journal article

Dabrowski, K. and Lozin, V. and Raman, R. and Ries, B. (Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 2010) | Book

de Werra, D. and Costa, M.-C. and Picouleau, C. and Ries, B., Annals of Operations Research (2010) | Journal article

Birand, B. and Chudnovsky, M. and Ries, B. and Seymour, P. and Zussman, G. and Zwols, Y., Proceedings - IEEE INFOCOM: (2010) | Conference

Birand, B. and Chudnovsky, M. and Ries, B. and Seymour, P. and Zussman, G. and Zwols, Y., Proceedings of the Annual International Conference on Mobile Computing and Networking, MOBICOM: (2010) | Conference

T谋naz Ekim, Bernard Ries, Dominique De Werra, Discrete Mathematics & Theoretical Computer Science (2010) | Journal article

Bentz, C. and Costa, M.-C. and Picouleau, C. and Ries, B. and de Werra, D., Journal of Graph Algorithms and Applications (2009) | Journal article

Costa, M.-C. and de Werra, D. and Picouleau, C. and Ries, B., Discrete Optimization (2009) | Journal article

Furma?czyk, H. and Kosowski, A. and Ries, B. and Zyli?ski, P., Discrete Mathematics (2009) | Journal article

Zenklusen, R. and Ries, B. and Picouleau, C. and de Werra, D. and Costa, M.-C. and Bentz, C., Discrete Mathematics (2009) | Journal article

Ries, B., Electronic Notes in Discrete Mathematics (2009) | Journal article

De Werra, D. and Costa, M.-C. and Picouleau, C. and Ries, B., 4OR (2008) | Journal article

Ries, B. and de Werra, D., European Journal of Combinatorics (2008) | Journal article

Costa, M.C. and De Werra, D. and Picouleau, C. and Ries, B., Graphs and Combinatorics (2008) | Journal article

Bentz, C. and Costa, M.C. and De Werra, D. and Picouleau, C. and Ries, B., Networks (2008) | Journal article

Costa, M.C. and Werra, D.D. and Picouleau, C. and Ries, B., Graphs and Combinatorics (2007) | Journal article

Ries, B., Discrete Applied Mathematics (2007) | Journal article

Costa, M.-C. and de Werra, D. and Picouleau, C. and Ries, B., Electronic Notes in Discrete Mathematics (2005) | Journal article

Research projects

Start	01.05.2023
End	31.07.2023
Funding	SNSF
WG conferences (Workshop on Graph-Theoretic Concepts in Computer Science) aim to connect theory and applications by demonstrating how graph-theoretic concepts can be applied in various areas of computer science. Organised in a different place each year, their goal is to present the strongest recent results and to identify and explore directions for future research. The Program Committee, composed of international experts in the field of theoretical computer science, decides on the accepted papers taking into account the reviews received for each submitted paper. A special issue of Springer's Lecture Notes in Computer Science will be published containing the accepted papers. The 49th edition of the International Workshop on Graph-Theoretic Concepts in Computer Science (WG 2023) will be held at the 糖心Volg from June 28 to 30, 2023. It will be organised by the applicant together with Prof. Daniel Paulusma from Durham University (UK). Both will also chair the Program Committee. There will be three internationally-reknowned invited speakers: Prof. Flavia Bonomo, Dr. Eunjung Kim and Dr. Nicolas Trotignon.

Start	01.09.2019
End	31.08.2022
Funding	Innovation
In Swiss municipalities, a curbside system is often used to collect the non-recoverable solid waste. In principle, the trucks stop at every household for the collection. Due to the many stops of the heavy trucks, this classic strategy causes high fuel consumption, emissions and noise. The objective of this project is to improve the municipal solid waste collection process by designing efficient and sustainable waste collection strategies targeted to the needs of the municipalities. This objective is pursued through the following three components. First, new waste collection concepts are proposed using modern physical waste collection elements, such as electric vehicles and containers with compressors. For example, small, agile vehicles may bring the garbage bags to larger containers in intermediate depots and large vehicles may then regularly discharge these containers. Second, mathematical models and optimization algorithms are developed for deciding how to design a waste collection concept for a given municipality in the best possible way. Typical decisions are about the locations of the waste collection points, the types of vehicles used to collect the waste at all collection points and the routing of each vehicle. Third, an interactive decision support tool is developed. It enables to specify the inputs, such as the street network and the waste quantities, and to display the results of the optimization algorithms for all alternatives. This tool will help the decision-makers to choose the best waste collection concept for their municipality.

Teaching and courses

Show in course program