Agenda

Département
Langue
Date
Thématique
2026

March

  • 12:45
    13:45

    The performance of mobility systems no longer relies solely on technology. AI, automation, hypervision, new uses: everywhere, the human factor is emerging as a key determinant of the safety, acceptability, and efficiency of transport services.

    During this scientific event, CATIE (Aquitaine Center for Information Technology and Electronics) https://www.catie.fr/language/fr/accueil/ will offer concrete feedback on how to integrate the human factor into the design of mobility systems and services. Using real-life cases from the aviation, rail, and road sectors, we will explore how analyzing behavior, physiological states, and human-system interactions can help us overcome the limitations of purely technological approaches.

    This session is aimed at researchers, doctoral students, and innovation stakeholders who want to better understand how the human factor can be integrated operationally into the design of tomorrow's mobility solutions.

    Speaker: Florian Larrue, Head of the Human-Centered Systems Department – CATIE

    Registration link.     

     

    Visio
  • 14:00
    15:00

    Given a graph $G$ and an integer $k \geq 2$, let $\chi'_k(G)$ denote the minimum number of colours required to colour the edges of $G$ such that, in each colour class, the subgraph induced by the edges of that colour has all non-zero degrees congruent to $1$ modulo $k$. In 1992, Pyber proved that $\chi'_2(G) \leq 4$ for every graph $G$, and posed the question of whether $\chi'_k(G)$ can be bounded solely in terms of $k$ for every $k \geq 3$. This question was answered in 1997 by Scott, who showed that $\chi'_k(G) \leq 5k^2 \log k$, and further asked whether $\chi'_k(G) = O(k)$. Recently, Botler, Colucci, and Kohayakawa (2023) answered Scott’s question affirmatively, proving that $\chi'_k(G) \leq 198k - 101$, and conjectured that the multiplicative constant could be reduced to $1$. A step towards this latter conjecture was made in 2024 by Nweit and Yang, who improved the bound to $\chi'_k(G) \leq 177k - 93$.

    In this talk, we will discuss the details of how we reduced this multiplicative constant to $9$ and present further open questions concerning modular colouring of graphs.

    (Pedro Mariano Viana Neto) [Instituto de Matemática e Estatística, São Paulo]

    Vérifiez que vous êtes bien inscrits sur le site du [gdr-ifm-gt-graphes] : [ https://gtgraphes.labri.fr/pmwiki/pmwiki.php/Equipes/Equipes#membres | https://gtgraphes.labri.fr/pmwiki/pmwiki.php/Equipes/Equipes#membres ]

    Remarks / Remarques

    Find all the information of the working group on this [ https://graphesetoptimisation.labri.fr/pmwiki.php/Groupe/GT?userlang=en | web page ] .
    Retrouvez toutes les informations du GT sur cette [ https://graphesetoptimisation.labri.fr/pmwiki.php/Groupe/GT | page web ] .

    English
    LaBRI/178
  • 13:00
    14:00

    Between 2018 and 2024, the American company Digital Realty built four data centers at the Port of Marseille-Fos, an industrial hub located on the northern coast of Marseille. The port seized the opportunity offered by the city's growing role in global data exchanges. Over the past decade, Marseille has risen from 44th to 5th place among the world's most connected cities. Since 2021, the city of Marseille and activist groups have been contesting the establishment of data centers. In this context, this presentation will examine how the convergence (or divergence) of interests between regional state agencies and private infrastructure players influences the establishment of data centers in Marseille.

    Biography: Loup Cellard holds a PhD in Interdisciplinary Studies from the Centre for Interdisciplinary Methodologies (University of Warwick, UK). He is currently a postdoctoral researcher at LISN and a member of the observatory on the environmental impact of AI at the ENS's AI and Society Institute. Previously, Loup Cellard was a researcher at the Datactivist cooperative.

     

    Salle 178
  • 12:30
    13:00
    Café science ouverte

    Anna Loeff, Research Data Project Manager, Cross-functional Research Support Service (DIRDOC), will host a webinar.
    Presentation of the multidisciplinary national data warehouse Recherche Data Gouv, the institutional space of the University of Bordeaux, and details of the procedure for submitting and promoting your data.

    Registration.

    This short format (30 min) aims to raise awareness of the challenges and practices of open science among the entire Bordeaux university community, particularly researchers and doctoral students.
     

  • 14:00
    15:00

    In automated learning problems, the task is to find a model that maps given inputs to their corresponding outputs as accurately as possible. Over the past 30 years, machine learning and deep learning have achieved tremendous success in solving this type of problem. However, while the resulting models can be used to make predictions, they offer limited interpretability, i.e. they provide little insight into *how* they solve the problem. For instance, if we train a recurrent neural network to predict whether a sequence of events will lead to a crash, the model cannot describe the sequences of events that lead to crashes and provide solutions to remediate the issue. Program synthesis is a framework for solving learning problems with models that are programs in a domain-specific language, which allows creating interpretable models in the domain of the problem.

    In this talk, I will present an enumerative approach for learning Linear Temporal Logic (LTL) formulas from data. I will begin with an introduction to program synthesis, using examples from program de-obfuscation and anomaly explanation. In the second part, I will present the main techniques used in our algorithm: observational equivalence and domination, two pruning techniques used to reduce the search space, and a connection between LTL Learning and the Boolean Set Cover problem. Finally, I will discuss the engineering choices we made when implementing this algorithm in Bolt, an open-source tool available at https://github.com/SynthesisLab/Bolt.

    This talk is based on joint work with Nathanaël Fijalkow, Théo Matricon, Baptiste Mouillon and Pierre Vandenhove.

    English
    LaBRI

April