Seminars and Colloquium
OMeGA
- Past conferences:
-
We are excited to announce the 17th International Conference on Artificial Evolution (EA 2026), which will take place in Nice, France, in October 2026.
EA is a non-profit conference that brings together researchers working on:
- evolutionary computation
- optimization & metaheuristics
- machine learning
- complex systems & artificial intelligence
This edition will particularly highlight the exciting intersection between metaheuristics and machine learning, a rapidly growing research area.
We strongly encourage in-person participation to foster scientific interaction, discussion, and collaboration.
Accepted papers will be published in the conference proceedings, with a selection invited to the prestigious Springer LNCS series.
More information: https://ea2026.inria.fr/ -
We are pleased to announce the 2026 Summer School on Hybrid Metaheuristics with Learning Approaches, taking place June 29 – July 2, 2026 at the Université de Haute-Alsace (France).
This 4-day intensive program will explore modern optimization methods at the intersection of Artificial Intelligence, Operations Research, and Data Science.
Many real-world optimization problems—arising in logistics, energy systems, transportation, and healthcare—are large-scale, nonlinear, and highly constrained. To address these challenges, researchers increasingly rely on hybrid approaches combining mathematical optimization, metaheuristics, and machine learning.
What participants will learn ?
• Mathematical modeling and exact optimization methods (MILP, Gurobi)
• Metaheuristics and approximate algorithms
• Machine learning for data-driven optimization
• Surrogate models for computationally expensive problems
• Hyper-heuristics for algorithm selection and generation
Participants will work on a practical case study on Electric Vehicle Charging Scheduling (EVCS), illustrating how hybrid AI approaches can address emerging challenges in sustainable mobility and energy systems.
Final Challenge:
On the last day, participants will take part in a hands-on optimization challenge based on the EVCS problem.
Three prizes will be awarded to the best performing solutions.
Room 201, Building K, FST, 18 Rue des Frères Lumière, Mulhouse
-
Le transport optimal barycentrique consiste à transporter une mesure μ vers une mesure ν en ne payant, pour chaque point, que la distance à son barycentre d’arrivée. Dans cet exposé, je m’intéresserai à ce problème sur les espaces à courbure majorée. Je commencerai par quelques rappels sur ces espaces (triangles minces) et sur le transport barycentrique, en particulier le théorème de structure de Gozlan et Juillet. Je présenterai ensuite des résultats récents, obtenus avec Shin-ichi Ohta et Nathael Gozlan, qui étendent (partiellement) ce théorème à ces espaces courbes.
-
Hypocoercive methods allow to prove the longtime convergence of the law of degenerate stochastic processes such as Langevin dynamics or random time HMC. From a technical viewpoint, these approaches usually involve a change of scalar product (as in the H^1 approach à la Villani, or the L^2 approach of Hérau and Dolbeault/Mouhot/Schmeiser). I will discuss two approaches which do not require such a change of scalar product, and henceforth provide the current sharpest quantitative estimates on the resolvent of the generator, which makes it possible for instance to bound the variance of estimators based on time averages along a realization of the process. The first approach, originally due to Armstrong/Mourrat, was adapted to dynamics on the whole space by Cao/Lu/Wang, and is based on space-time Poincare inequalities. I will review some progress made with Giovanni Brigati on better understanding the algebraic structures behind this method, and possibly mention extensions to weak/weighted Poincaré inequalities (in collaboration with Lihan Wang and Andi Wang). The second approach, developed with Etienne Bernard, Max Fathi and Antoine Levitt, is based on Schur complements and provides direct bounds on the resolvent using the specific saddle-point like structure of the generator under an appropriate orthogonal decomposition of L^2.
-
TBA
-
TBA
-
TBA
- Past conferences:
-
C*-algebra theory is often touted as “non-commutative topology”, although making this precise has proved challenging. The starting point is the classic Gelfand duality, which says that every commutative C*-algebra is isomorphic to a C*-algebra of continuous functions, specifically on some locally compact Hausdorff space. What then would be an analogous “non-commutative space” for non-commutative C*-algebras? Renault’s answer is to consider étale groupoids, which do indeed give rise to non-commutative C*-algebras of continuous functions under convolution. Building on earlier work of Kumjian, he was even able to extend the classic Gelfand duality under an extra “effective” assumption on the groupoids. The past decade or so has seen various extensions of this result, although some residual assumptions on the groupoid have remained. In recent work with Ying-Fen Lin, Kathryn McCormick and Lisa Orloff Clark, we were able to completely remove the effective assumption and even extend Renault’s duality to more general completions of convolution algebras. In this talk we will outline how to achieve this, including all the relevant background on étale groupoids and their C*-algebras.
-
Afin d’étudier la fonction zéta,L.Euler introduit en 1775 les valeurs zétas multiples (MZVs) comme une généralisation à plusieurs variables définie sur l’ensemble des mots sur l’alphabet N^∗. Depuis, ces fonctions apparaissent dans des domaines variés des mathématiques : en arithmétique géométrique, en théorie des nombres ou encore en théorie quantique des champs. Par conséquent, leurs études peut se faire en utilisant des approches assez différentes comme l’analyse complexe, l’intégration motivique ou encore d’autres techniques algébriques. Parmi les motivations principales, la détermination des relations rationnelles entre les MZVs de même poids a des répercussions en physique théorique. Selon une conjecture de Hoffman dans les années 90, ces relations sont déterminées par des relations dites de double mélange régularisée.
Dans cet exposé, nous nous concentrerons sur une autre généralisation des MZVs initialement introduite par J. Ecalle en 1981 puis mise en évidence par D. Manchon en 2016 : les valeurs zétas arborifiées (AZVs).
Tout d’abord, après une introduction historique aux MZVs, nous détaillerons l’importance des représentations intégrales et en séries de quantités (elles donnent lieu respectivement à des morphismes de mélange et quasi-mélange pour les mots) et leur connexion via l’application s dite de Kontsevich. Cela nous permettra de formuler la première conjecture de Hoffman.
Puis, nous introduirons les AZVs comme des applications associant à des arbres décorés de manière appropriée un nombre réel pouvant être exprimé via une représentation intégrale ou en série. En utilisant des techniques algébriques utilisant les algèbres dendriformes, nous décrirons une notion de mélange et quasi-mélange d’arbres ainsi qu’un analogue de l’application
de Kontsevich. Tout cela, nous permet de donenr une conjecture de double mélange régularisée
sur les AZVs impliquant celle de Hoffman pour les MZVs classiques.
(Travail en collaboration avec P. Clavier et K-Y. Fan) -
In the talk I will give a gentle historical introduction to several topics that served as a motivation for the study of analysis and stochastic analysis on the space of probability measures over a closed Riemannian manifold.
The talk will touch on motivations from conservative parabolic pdes, metric measure geometry, the representation theory of large Lie groups, and the physics of systems at the mesoscopic scale. If time allows, I will review the state of the art about constructions of the Brownian motion on spaces of probability measures. -
(October 8, 2026 - 15:00) — Antoine Lejay (Univ. Nancy) — Autour du théorème de Butcher pour les méthodes de Runge-Kutta
-
The study of ship stability under random sea states is an important problem in naval engineering. In this talk, we focus on the roll motion of a ship subjected to beam seas and random wave excitation. We consider a nonlinear stochastic model describing the ship roll dynamics, coupled with filtered random excitation. The resulting dynamics can be described by a high-dimensional Fokker–Planck equation. We develop a second-order asymptotic approach to approximate its solution and investigate the long-time behavior of the corresponding stochastic system. Particular attention will be paid to the mathematical structure of the model and the asymptotic analysis of the probability density. Some numerical aspects related to the solution of the Fokker–Planck equation will also be briefly discussed. The objective is to provide a mathematical and computational framework for studying ship responses under random sea conditions and their implications for ship stability.
-
Il est habituel de présenter les résultats d’un championnat sportif sous la forme d’un tableau où figure sur une des colonnes le nombre de victoires par équipe. Lorsque n équipes se sont toutes affrontées, ce vecteur peut devenir (0,1,\ldots,n-1) pour un championat hiérarchisé à l’extrême, ou bien au contraire un vecteur dont les composantes sont d'avantage ramassées autour de (n-1)/2. Un théorème de E. Landau, généralisé par Moon, exprime une condition nécessaire et suffisante à être ce vecteur, ceci à l’aide de l’ordre partiel de la « majoration ». Alors que cette condition se traduit facilement en terme d’espérance conditionnelle, c’est seulement récemment en 2022 qu’une démonstration probabiliste du théorème de Moon a été proposée par Aldous et Kolesnik. Dans cette démonstration les auteurs s’appuient sur une image, celle d’un modèle statistique « du football ». Notre travail, avec Gaoyue Guo (Paris Saclay) et Wenpin Tang (Columbia University), a consisté à envisager cette démonstration dans le cadre d’un problème de transport martingale afin de la rendre plus tangible et de d'obtenir de nouvelles propriétés.
-
Il existe plusieurs notions de borne de courbure de Ricci pour les graphes et les groupes. Y. Ollivier a proposé une approche via le transport optimal à la Lott-Villani-Sturm. D. Bakry et M. Emery ont proposé une autre approche via la théorie des diffusions et la formule de Bochner en géométrie riemmanienne. Le but de l’exposé sera de montrer, via cette deuxième approche, comment donner des versions discrètes de résultats classiques en analyse sur les variétés (Bisoop-Gromov, Li-Yau, Harnack, Poincaré, …).
-
Optimal stopping theory, developed through seminal works of Dynkin, Shiryaev, and others, is a fundamental topic in probability, stochastic control, and mathematical finance. Classical approaches typically rely on dynamic programming principles and the Snell envelope, which characterize the value function through backward recursive procedures. While these methods provide a powerful theoretical framework, alternative computational approaches have also been investigated.
In this talk, I will first review some classical optimal stopping problems and discuss Irle’s forward algorithm for finite-state Markov processes. In contrast to traditional backward methods, Irle’s approach constructs the value function through a forward iterative procedure, leading to an efficient computational framework and new insights into the structure of optimal stopping problems.
Motivated by these ideas, I will then consider a two-player zero-sum stopping game driven by a homogeneous Markov process on a finite state space. Such games extend optimal stopping problems to a setting with competing players and strategic interactions. I will present a new algorithm for computing the value function of the game, which can be viewed as a game-theoretic extension of Irle’s forward algorithm. The convergence of the method, the number of iterations required, and several numerical examples illustrating its performance will also be discussed. -
The problem of estimating the maximal number H(m) of limit cycles that planar polynomial vector fields of degree m can exhibit has long been a central question in the qualitative theory of planar dynamical systems. A natural extension to the threedimensional space is to study the maximum number N(m) of limit tori that can occur in spatial polynomial vector fields of degree m. In this work, we focus on normally hyperbolic limit tori and show that the corresponding maximum number N_h(m), if finite, increases strictly with m. More precisely, we prove that N_h(m+1) ⩾ N_h(m)+ 1. Our proof relies on two central results established in this paper. The first is that the normal
hyperbolicity of compact invariant manifolds is preserved under time reparametrizations.Despite the fundamental nature of this statement, a complete proof has, surprisingly, not previously appeared in the literature, except under rather restrictive assumptions on the flow restricted to the invariant manifold. The second result concerns the torus bifurcation phenomenon near Hopf–Zero equilibria in spatial vector fields. While the conditions for such bifurcations are typically expressed in terms of higher-order normal form coefficients, we derive explicit and verifiable criteria for the occurrence of torus bifurcation, assuming only that the linear part of the unperturbed vector field is in Jordan normal form.
This approach not only circumvents intricate computations involving higher-order normal forms but also ensures the normal hyperbolicity of the bifurcated torus.
-
The area of stochastic partial differential equations has seen rapid progress over the past decade, spurred by the introduction of the theory of regularity structures and of para-controlled calculus. Despite the close connections of singular SPDEs to physical phenomena, the theory of singular SPDEs has largely been developed homogeneous settings, involving constant-coefficient operators.First I shall motivate the study of SPDEs in heterogeneous environments using the examples of Φ^4 as a model of ferromagnetism and the parabolic Anderson model as it relates to branching processes.After recalling the renormalisation of the classical homogeneous versions of these equations, I will describe what changes in the variable-coefficient setting. In particular, I will present a natural choice of renormalisation functions that is local and, for sufficiently covariant regularisations of the noise, explicit.The talk will be non-technical and focused on the main ideas.
-
In this talk, we consider a compact hyperbolic surface with finite order singularities and its unit tangent bundle.
We consider also the twisted Selberg zeta function associated with an arbitrary, finite-dimensional representation of the fundamental group of the unit tangent bundle.
We will present recent results concerning a relation between the twisted Selberg zeta function and the regularized determinant of the twisted Laplacian. The main tool we use is the Selberg trace formula. If the surface has no finite order singularities, we obtain as a corollary a corresponding relation. These results can be viewed as an extension to the non-unitary twists case of the results by Sarnak and Naud. This is joint work with Jay Jorgenson and Lejla Smajlovic. -
Given a germ of analytic vector field ∂, let ∂= ∂_ss + ∂_nilp be its unique formal Jordan decomposition, where ∂_ss is its semi-simple component and ∂_nilp is its nilpotent component. When ∂ is logarithmic, we define the Bruno ideal B(∂) as the formal locus where the semi-simple and the nilpotent components are collinear, that is, the vanishing locus of ∂_ss ∧ ∂_nilp.
We prove the following result originally stated by A. D. Bruno: If the eigenvalues of ∂_ss satisfy an arithmetic condition, then B(∂) is analytic and the restriction of ∂ to its zero set V is analytically normalizable.
This is a joint work with Daniel Panazzolo. -
Une triangulation d’un ensemble de points dans le plan euclidien est dite de Delaunay si chaque cercle circonscrit à un triangle ne contient aucun autre sommet de la triangulation. Son extension à des surfaces, ainsi que certains algorithmes permettant de la calculer, se heurte à des difficultés topologiques (genre de la surface) et géométriques (systole de la surface).
Cet exposé introduira la notion de triangulation de Delaunay, et présentera des méthodes de calcul permettant de la calculer comme l’algorithme de flip ou de Bowyer-Watson. Nous nous focaliserons ensuite sur ce-dernier, en l’étendant d’abord au tore, puis aux surfaces hyperboliques, en passant par la surface de Bolza. Aucun prérequis en géométrie hyperbolique, topologie ou algorithmique n’est nécessaire pour suivre l’exposé. -
In this talk I will report on a recent joint work with Chiara Esposito and Michael Heins on convergence properties of Drinfel’d twists. A formal Drinfel’d twist is a formal power series in \(hbar\) with entries in the tensor power of the universal enveloping algebra of a Lie algebra with itself such that certain algebraic conditions are satisfied. These algebraic properties can either be interpreted as defining an associative formal product on the corresponding Lie group by left translations. Alternatively, they can be used to define formal associative deformations of any algebra on which the Lie algebra acts by derivations by a universal deformation formula (UDF). We study now the situation of locally convex algebras and consider the space of $R$-analytic and \(R\)-entire vectors with respect to the representation. These spaces are generalizations of the usual analytic and entire vector depending now on a parameter $R$ which controls the growth of their Taylor coefficients. Once the twist satisfies a certain continuity condition we show that one obtains convergence of the UDF thus leading to a non-formal deformation. Several examples illustrate that this is a promising and rich scenario to obtain convergence deformations.
-
Après un bref rappel historique sur les B-séries, nous introduirons le cadre catégorique naturel à leur étude.Nous verrons ensuite que certaines techniques classiques d’algèbre supérieure fournissent des résultats d’analyse numérique via ce contexte catégorique.
-
Invariant compact manifolds, such as equilibria, periodic orbits, and invariant tori, provide important information about the dynamics of differential systems. This knowledge is significantly increased when we can describe the behavior of nearby trajectories. In this talk, we present conditions that ensure the existence of invariant tori in perturbed differential systems, along with results on their regularity, stability, and dynamics. These conditions are based on higher-order averaged equations and extend classical theorems by Krylov, Bogoliubov, Mitropolsky, and Hale. As an application, we also explore a three-dimensional version of Hilbert’s 16th Problem, focusing on the number of isolated invariant tori in 3D polynomial vector fields.
Analysis
- Past conferences:
-
Le département de maths accueille le chercheur Lorenzo Dello Schiavo de l'Università degli Studi di Roma “Tor Vergata” sur poste rouge du CNRS du 1er octobre au 30 novembre. A cette occasion Lorenzo fera une série de mini-cours intitulés Analytical methods for Markov processes : Dirichlet forms, dans le cadre du groupe de travail
"Théorie Géométrique des équations paraboliques
semi-linéaires et applications"
(pour plus d'informations : https://irimas.math.cnrs.fr/groupe-parabolique/ )
IMTIS
-
(From November 15, 2026 to November 20, 2026) — Stéphane Bazeille — Applications de la robotique industrielle aux processus de laboratoire Journées thématiques SMART MICROSCOPY du Réseau Technique -microscopie fonctionnelle multimodale, Centre CNRS Paul Langevin Aussois
-
(From November 15, 2026 to November 20, 2026) — O. Haeberlé — Introduction à la programmation évènementielle et au pilotage parallélisé Journées thématiques SMART MICROSCOPY du Réseau Technique -microscopie fonctionnelle multimodale, Centre CNRS Paul Langevin Aussois
- Past conferences:
-
(From November 1, 2026 to November 6, 2026) — O. Haeberlé — Invited speaker to Computational Optical Microscopy Bad Honnef, Germany
-
Researchers from IRIMAS IMTIS (UHA) participated in a scientific workshop hosted by the European Institute for Energy Research (EIFER) in Karlsruhe, Germany, alongside partners from EDF and the Karlsruhe Institute of Technology (KIT).
The workshop provided an opportunity to review the research progress of PhD candidate Thomas Debarre, discuss the next stages of his doctoral work, and exchange perspectives on current challenges in energy systems.
The scientific programme included presentations and discussions covering several research topics:
Renewable energy integration: Recent regulatory developments in Germany, presented by EIFER.
Power grid planning: The RAPSODI and PLANET projects, with a focus on long-term electricity network planning, presented by EDF.
Energy supply resilience: Security of electricity and gas supply under extreme weather conditions, presented by KIT.
From our side, we highlighted ongoing experimental research on PV integration, energy self-consumption and smart EV charging, illustrating the application of intelligent energy management strategies.
This workshop strengthened scientific exchanges between IRIMAS , EIFER, EDF and KIT, while identifying opportunities for further collaboration on the planning, resilience and intelligent management of future energy systems. -
How can photovoltaics be integrated into vineyards while addressing the climate challenges facing viticulture? This is one of the key issues at the heart of the Interreg Upper Rhine Agri-PV project, whose French, German and Swiss partners gathered for an initial meeting at the Ebenrain-Zentrum für Landwirtschaft, Natur und Ernährung in Sissach, Switzerland.
The partners visited one of the project’s pilot sites, where they were able to observe agrivoltaic installations in the field and discuss their implementation under real-world conditions.
The IRIMAS/IMTIS team was represented by Djaffar Ould Abdeslam, Titouan Sérandour, Bruno Colicchio, Mathieu Galinier and Bushra Canaan.
This first meeting marks an important milestone in launching the project’s scientific and technical activities and strengthening cross-border cooperation in renewable energy and sustainable agriculture. -
(August 2026) — O. Haeberlé — TOP 2% de Stanford (Authors Career) https://elsevier.digitalcommonsdata.com/datasets/btchxktzyw/9
-
09:30 – 10:00
Soumen Indu
Title: Intelligent Management of Energy Consumption Monitoring at IUTLab Using Machine Learning Techniques
Supervisor: Patrice Wira
10:00 – 10:30
Mbarek Oulghazi
Title: Quilted Nonstationary Gabor Frames: Towards Adaptive and Invertible Time–Frequency Representations
Supervisor: Ali Moukadem
10:30 – 11:00
Muhammad Sami Ur Rasul
Title: Fibers as Optical Resolution Test Patterns for Unlabeled Nanoscopy Assessment
Supervisor: Olivier Haeberlé -
10:00 – 10:30
Baptiste Hubner
Title: Parsimonious Particle Localization in Microscopy
Supervisor: Jean-Baptiste Courbot
10:30 – 11:00
Abdeljalil El Boughdadi
Title: Analysis and Modeling of a Real Smart Home for the Creation of a Database Dedicated to Anomaly Detection and Flexible Load Monitoring
Supervisor: Djaffar Ould Abdeslam
11:00 – 11:30
Raza Hassan
Title: Camera Calibration for Multi-View Depth Estimation
Supervisor: Stéphane Bazeille -
(June 11, 2026 - 18:30 to 20:00) — Stéphane Bazeille — Comment les robots perçoivent-ils le monde ? UP du Rhin, salle de conférences de la Cour des chaînes, 13 rue des Franciscains 68100 – Mulhouse
-
(June 4, 2026 - 15:00) — Salem Ait Messaoud — Simulation et édition de défauts par 3d Gaussian Splatting Mulhouse University of Technology, Room A004
-
(May 21, 2026 - 14:00) — Titouan Sérandour — Un modèle d’apprentissage profond pour la détection des nébuleuses planétaires sur des images astronomiques Mulhouse University of Technology, Room A004
-
-
(April 2, 2026 - 14:00) — Julie Munsch — Modèles graphiques et probabilistes pour la maintenance prédictive application à la classification et à la prévention d’évènements IUT Mulhouse, Salle A004
-
(March 19, 2026 - 14:00) — Carlos Alberto Chacon — Microscopie tomographique diffractive à double vue IUT Mulhouse, Salle A004
-
(March 5, 2026 - 14:00) — Simon Schabat — Segmentation des chromosomes dans des images de microscopie à fluorescence IUT Mulhouse, Salle A004