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      About <self>
      Research <publications.rst>
      Teaching <teaching.rst>
      Contact <contact.rst>

Sébastien Colla
===============

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|
| **Ph.D. student**
| |FRIA_link| Research fellow
|
| |INMA_link| - Mathematical Engineering Department
| |ICTEAM_link| - Institute of Information and Communication Technologies, Electronics and Applied Mathematics
| |UCLouvain_link| - Université Catholique of Louvain


| My advisor is |Julien_link|

| **Quick links** | |scholar_logo| |scholar_link| | |github| |github_link| | |linkedin_logo| |linkedin_link|


News
-----

+ (February 2024) I have submitted a paper to MTNS conference
      S. Colla and J. M. Hendrickx, "**On the Optimal Communication Weights in Distributed Optimization Algorithms**", submitted to MTNS 2024.
      [`PDF <_static/MTNS2024.pdf>`_, `arXiv <https://arxiv.org/abs/2402.05705>`_ ]
|vspace|

+ (September 2023) Check out our tutorial paper for CDC 2023
      A. Rubbens, N. Bousselmi, S. Colla and J. M. Hendrickx, "**Interpolation Constraints for Computing Worst-Case Bounds in Performance Estimation Problems**", tutorial paper for 62th IEEE Conference on Decision and Control (CDC), 2023.
      [`PDF <_static/CDC_2023_Tutorial_PEP.pdf>`_, `arXiv <https://arxiv.org/abs/2309.12173>`_ ]
|vspace|

+ (March 2023) My first journal paper has been accepted in IEEE Transactions on Automatic Control
      S. Colla, J. M. Hendrickx, "**Automatic Performance Estimation for Decentralized Optimization**", IEEE Transactions on Automatic Control, accepted, 2023.
      [`PDF <_static/Colla_Automatic_Performance_Estimation_for_Decentralized_Optimization.pdf>`_, `arXiv <https://arxiv.org/abs/2203.05963>`_, `DOI <https://doi.org/10.1109/TAC.2023.3251902>`_]
|vspace|

+ (February 2023) We have organized the first `PEP-talks <https://performanceestimation.github.io/PEP-talks/february_2023/index.html>`_ workshop in Louvain-la-Neuve. This workshop is focused on the theory and applications of Performance Estimation Problems (PEP) in continuous optimization.

Research Interests
------------------
- **Decentralized Optimization**
- Computer-aided worst-case analyses
- Multi-Agent system.

The goal of my thesis is to boost the research in decentralized optimization by creating tools allowing one to automatically compute the worst-case performance of any decentralized optimization algorithm,
and to identify the bottleneck instances, providing insight on what limits the performance.
This will contribute to a better understanding of decentralized optimization algorithms and enable rapid exploration of new algorithms ideas and their iterative improvement.

This project relies on the Performance Estimation Problem (|PEP|) approach developed by |Adrien_link| for classical centralized optimization during his thesis.
It relies on formulating the evaluation of an algorithm worst-case performance as an optimization problem itself,
whose variables are the objective functions and initial conditions. Such problems are very complex, but have been shown to be solvable exactly. The |PESTO| toolbox allows to write and solve them easily with Matlab. The equivalent Python toolbox, called `PEPit <https://github.com/PerformanceEstimation/PEPit>`_, has been released in 2022.

Here is a `Vulgarized Summary of my research project <_static/research_vulagrized_summary.pdf>`_ written in March 2021.

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.. |cdc_link| raw:: html

     <a href="https://arxiv.org/pdf/2103.14396.pdf" target="_blank" rel='noopener noreferrer'>PDF</a>

.. |Julien_link| raw:: html

   <a href="https://perso.uclouvain.be/julien.hendrickx/" target="_blank">Julien Hendrickx</a>

.. |ICTEAM_link| raw:: html

  <a href="https://uclouvain.be/en/research-institutes/icteam" target="_blank">ICTEAM</a>

.. |UCLouvain_link| raw:: html

  <a href="https://uclouvain.be" target="_blank">UCLouvain</a>

.. |FRIA_link| raw:: html

  <a href="https://www.frs-fnrs.be/en/financements/chercheur-doctorant#fria" target="_blank">FRIA</a>

.. |scholar_link| raw:: html

  <a href="https://scholar.google.fr/citations?user=g9mO2QcAAAAJ&hl" target="_blank">Google Scholar</a>

.. |github_link| raw:: html

  <a href="https://github.com/sebcolla" target="_blank">GitHub</a>

.. |INMA_link| raw:: html

  <a href="  https://uclouvain.be/en/research-institutes/icteam/inma" target="_blank">INMA</a>

.. |linkedin_link| raw:: html

  <a href="https://www.linkedin.com/in/sebcolla/" target="_blank">Linkedin</a>

.. |Adrien_link| raw:: html

  <a href="https://www.di.ens.fr/~ataylor/" target="_blank">Adrien Taylor</a>

.. |PEP| raw:: html

  <a href="https://francisbach.com/computer-aided-analyses/" target="_blank">PEP</a>

.. |PESTO| raw:: html

    <a href="https://github.com/AdrienTaylor/Performance-Estimation-Toolbox" target="_blank">PESTO</a>

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.. |scholar_logo| image:: data/images/Google_Scholar_logo.png
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