Biography

I obtained my Master in Engineering (Computer Science) from UCLouvain in 2005. I then obtained my Ph.D. in Computer Science from UCLouvain in 2009 under the supervision of Yves Deville, with a dissertation focused on balancing and fairness global constraints in Constraint Programming, as well as on Bin Packing. During my doctoral work, I also had the opportunity to collaborate with Jean-Charles Régin and my colleague Pierre Dupont.
After completing my Ph.D., I spent five months at Brown University (US), working with Pascal Van Hentenryck on the CP solver of Comet, which Pascal developed jointly with Laurent Michel. I subsequently joined Dynadec, the startup created by Pascal Van Hentenryck to commercialize Comet, where I worked for two years.
I then spent two years at the UCLouvain spin-off N-SIDE, where I initiated the development of the OscaR solver, before returning to UCLouvain as faculty in 2012. I continued leading the development of CP solver of OscaR until its retirement, after which it was succeeded by MiniCP and MaxiCP, which I actively maintain.
In recent years, my research has increasingly focused on decision-diagram-based optimization, a topic pioneered by Willem-Jan van Hoeve and John Hooker team. In collaboration with Cetic, we are now developing DDOLib, a solver built around these techniques. I also had a very fruitful collaboration with my former colleague Siegfried Nijssen the past years on algorithms for learning exact or less-greedy decision trees, during which we extended and exploited an idea originally developed by him and Lisa Fromont (DL8 algorithm) involving dynamic programming.
Over the years, I have also worked on numerous industrial optimization and machine-learning applications (scheduling, routing, configuration, etc.) across a variety of projects.
I have supervised 15 Ph.D. theses successfully defended. Two former PhD students (Hélène Verhaeghe and Quentin Cappart) are now my colleagues professors at UCLouvain. I also maintain active research collaborations across the African continent, including Ratheil Houndji (former PhD student now prof. at UAC, Benin) and Roger Kameugne (prof. at Maroua, Cameroon).

Research

Interests

• Constraint Programming and Discrete Optimization
• Dynamic Programming, Decision Diagrams, Path-Finding and Anytime Optimization Algorithms
• Data-mining and Machine Learning
• Algorithms and data-structures in general
• Programming languages

Current Projects and collaboration

• Dynamic Proggramming and MDD Solving, in collaboration with Emma Legrand, Roger Kameugne, and Cetic
• MDD for CP, in collaboration with Amaury Guichard, Hélène Verhaeghe
• VRP in collaboration with Augustin Declecluse
• Networking Optimization and Machine Learning , collaboration with Christel Pelsser and Alice Burlat
• LLM for construction, collaboration with Buildwise and Ioannis Kostis
• AI-based Defect detection for rails, collaboration with PEPPS and Augustin Crespin
• CP MOOC and CP solvers (www.minicp.org, www.maxicp.org), in collaboration with Laurent Michel, Pascal Van Hentenryck and Guillaume Derval

Past projects

• Traffic Engineering, in Software Defined Networks, in collaboration with Olivier Bonaventure (ARC project)
• Scheduling Operations for Steel-Making, in collaboration with PSI Metal (Metal Urbain, Innoviris Bxl)
• Interlocking Systems (verification and optimization), in collaboration with Alstom and Cetic (Inograms project, région Wallonne)
• Energy aware scheduling and planning in Industry, in collaboration with N-SIDE (Industore project, région Wallonne)
• CP-Solver Engineering tools, in collaboration with Michele Lombardi
• Matrix Mining, in collaboration with Vincent Branders and Pierre Dupont
• Bitwise algorithms for Table Constraints and MDD, in collaboration with Christophe Lecoutre
• Vehicule Routing and supply chain optimization, in collaboration with N-SIDE (Presupply project, région Wallonne)
• CP-Based Data-Mining, in collaboration with Tias Guns and Siegfried Nijssen
• B-Post Chair in Data-Science, in collaboration with Siegfried Nijssen (sponsored by B-Post)
• Migration analysis (GLOBMING ARC project), in collaboration with Frédéric Docquier and Siegfried Nijssen
• Learning and Optimization Models in collaboration with PSI Metals, Siegfried Nijssen, Tias Guns, Gael Aglin (Reconcile Innoviris Project Bxl)
• Intelligent Planning with Traxeo (Deep Construct Walloon Region project)
• Scheduling the unmounting of plances , (Planum Project, région Walllonne)