Résultats de recherche

Abstract Detecting semantic code clones in logic programs is a longstanding challenge, due to the lack of a unified definition of semantic similarity and the diversity of syntactic expressions that can represent similar behaviours. This thesis introduces a formal and flexible framework for semantic clone detection based on Constrained Horn Clauses (CHC). The approach considers two predicates as semantic clones if they can be independently transformed, via semantics-preserving program transformations, into a common third predicate. At the core of the method lies anti-unification, a process that computes the most specific generalisation of two predicates by identifying their shared structural patterns. The framework is parametric in regard with the allowed program transformations, the notion of generality, and the so-called quality estimators that steer the anti-unification process. Jury Prof. Wim Vanhoof - University of Namur, BelgiumProf. Katrien Beuls - University of Namur, BelgiumProf. Jean-Marie Jacquet - University of Namur, BelgiumProf. Temur Kutsia - Johannes Kepler University, AustriaProf. Frédéric Mesnard - University of the Reunion, Reunion IslandProf. Paul Van Eecke - Free University of Brussels, Belgium

BNAIC/BeNeLearn 2025 will be held at the University of Namur under the auspices of the Belgian-Dutch Association for Artificial Intelligence (BNVKI) and the Dutch Research School for Information and Knowledge Systems (SIKS). The conference aims at presenting an overview of state-of-the-art research in artificial intelligence and machine learning in Belgium, The Netherlands, and Luxembourg. More information and registration

Abstract In recent decades, the volume of data generated worldwide has grown exponentially, significantly accelerating advancements in machine learning. This explosion of data has led to an increased need for effective data exploration techniques, giving rise to a specialized field known as dimensionality reduction. Dimensionality reduction methods are used to transform high-dimensional data into a low-dimensional space (typically 2D or 3D), so that it can be easily visualized and understood by humans. Algorithms such as Principal Component Analysis (PCA), Multidimensional Scaling (MDS), and t-distributed Stochastic Neighbor Embedding (t-SNE) have become essential tools for visualizing complex datasets. These techniques play a critical role in exploratory data analysis and in interpreting complex models like Convolutional Neural Networks (CNNs). Despite their widespread adoption, dimensionality reduction techniques, particularly non-linear ones, often lack interpretability. This opacity makes it difficult for users to understand the meaning of the visualizations or the rationale behind specific low-dimensional representations. In contrast, the field of supervised machine learning has seen significant progress in explainable AI (XAI), which aims to clarify model decisions, especially in high-stakes scenarios. While many post-hoc explanation tools have been developed to interpret the outputs of supervised models, there is still a notable gap in methods for explaining the results of dimensionality reduction techniques. This research investigates how post-hoc explanation techniques can be integrated into dimensionality reduction algorithms to improve user understanding of the resulting visualizations. Specifically, it explores how interpretability methods originally developed for supervised learning can be adapted to explain the behavior of non-linear dimensionality reduction algorithms. Additionally, this work examines whether the integration of post-hoc explanations can enhance the overall effectiveness of data exploration. As these tools are intended for end-users, we also design and evaluate an interactive system that incorporates explanatory mechanisms. We argue that combining interpretability with interactivity significantly improves users' understanding of embeddings produced by non-linear dimensionality reduction techniques. In this research, we propose enhancements to an existing post-hoc explanation method that adapts LIME for t-SNE. We introduce a globally-local framework for fast and scalable explanations of t-SNE embeddings. Furthermore, we present a completely new approach that adapts saliency map-based explanations to locally interpret non-linear dimensionality reduction results. Lastly, we introduce our interactive tool, Insight-SNE, which integrates our gradient-based explanation method and enables users to explore low-dimensional embeddings through direct interaction with the explanations. Jury Prof. Wim Vanhoof - University of Namur, BelgiumProf. Benoit Frénay - University of Namur, BelgiumProf. Bruno Dumas - University of Namur, BelgiumProf. John Lee - University of Louvain, BelgiumProf. Luis Galarraga - University of Rennes, France

Professeur en sécurité informatique à l’Université de Namur, Florentin Rochet a fait de la cryptographie appliquée et des communications sécurisées son domaine d’expertise. Entre progression galopante de l’intelligence artificielle et solutions open source, il partage son analyse de la situation actuelle et livre ses perspectives pour l’avenir. 

Dans le cadre des Inforums et des séminaires CyberExcellence, nous aurons le plaisir d’accueillir le Dr. Ryan Wails (Georgetown University), qui nous parlera de cyber-sécurité. Vous trouverez l’abstract de sa présentation ainsi que sa bio ci-dessous.Pas d'inscription nécessaire.Nous espérons vous retrouver nombreux·ses à cet événement !On the Interplay of Modern Traffic Analysis and Internet Censorship & Circumvention TechniquesIn this talk, I will review the current state of real-world Internet censorship and some tools that network users employ to circumvent censorship. Then, I'll take a prospective view about how censors might incorporate modern ML-based traffic analysis techniques to block users, motivating the need for stronger circumvention tools. Finally, I'll discuss our new internet censorship evasion technique called Unidentified Protocol Generation (published at USENIX Security 2025, which is able to evade detection by state-of-the-art traffic analysis.Author bio: Ryan Wails is a Postdoc a Georgetown University researching network privacy and security. He has been doing his PhD while working at the US Naval Research Laboratory. This lab is known for originating the Tor network, and creating the PETs research community which is now among the top international research communities in computer security. Ryan is a core contributor of the Tor project and has published in top conferences on Networking simulators, privacy attacks, privacy-preserving measurements, path selection algorithms, censorship circumvention, and website fingerprinting. He received several international disctinctions, including Best papers in top conferences and award recognitions at community events for his contributions.

Le 13 mai dernier se tenaient les présentations des projets de génie logiciel (projet MDL de son petit nom) devant le jury composé des coachs et des clients externes venus pour l’occasion. À travers les 7 projets présentés cette année, les étudiants ont pu montrer leurs réalisations, mais aussi expliquer comment ils ont interagi avec leurs clients pour mener à bien leurs développements.

Une initiative pédagogique originale a été menée à l’Université de Namur durant l’année académique 2024‑2025 dans le cadre du cours Test et Qualité logicielle du master en informatique, orientation software engineering. Cette démarche a conduit à la publication du SNAIL Report 2025, un véritable baromètre des pratiques de développement logiciel en Fédération Wallonie‑Bruxelles.

Enseignée par les Pères jésuites dans les programmes de la Faculté des sciences dès le milieu du 19e siècle, c’est en 1972 que la chimie connait son essor à l’UNamur avec l’ouverture des programmes de licence. Quatorze étudiants audacieux font confiance aux nouvelles équipes. Parmi eux, Daniel Vercauteren, Professeur Emérite, est toujours présent à l’UNamur. A l'occasion du 50ème anniversaire des premières licences du Département de chimie, il partage quelques moments clés de la présence de la chimie à l’UNamur.

Dernièrement, et grâce à LUMI, l’un des plus gros supercalculateurs européens, les limites de nos connaissances en matière de membranes lipidiques de cellules ont été repoussées. Une équipe de chercheurs namurois, composée du Professeur Benoît Champagne et des Docteurs Pierre Beaujean et Charlotte Bouquiaux, vient de publier dans la revue Journal of Chemical Information and Modeling. Les résultats de cette étude ouvrent la voie pour de nouvelles approches dans le domaine de la thérapie lipidique membranaire.

Un an après l’obtention d’un financement du Conseil Européen de la Recherche (ERC) pour son projet B-Yond, le Prof Guillaume Berionni vient d’être nommé membre de la prestigieuse société européenne de chimie Chemistry Europe. Cette distinction fait de lui le nouveau représentant pour la Belgique pour une période de 2 ans.

(Mise à jour 04/04 : Cet article est "un poisson d'avril") Un événement remarquable a eu lieu lors du Printemps des sciences qui se déroulait du 18 au 24 mars 2024. Alors qu’une visite de l’Observatoire astronomique de l’UNamur était offerte au grand public le soir du 23 mars, un phénomène unique s’est produit.

Comment la chimie participe-t-elle à développer des solutions innovantes et durables pour les défis actuels et futurs de la société ? Quelles méthodes pédagogiques singulières, l’UNamur met-elle en place pour former des leaders éclairés dans le domaine de la chimie ? A l’occasion de ses 50 ans, le Département de chimie lève le voile sur quelques-uns de ses projets de recherche d’envergure et sur ses pratiques pédagogiques innovantes.