54: Coveille a structuring project for UTC-LMAC

It was in the context of the ongoing health crisis due to Covid-19 that the National Institute of Mathematical Sciences and their Interactions (INSMI), one of the ten CNRS institutes, decided to set up a platform to coordinate actions involving modelling Covid-19 phenomena.

54: Coveille a structuring project for UTC-LMAC

UTC-LMAC beyond Coveille

A full university professor, Florian De Vuyst has been Director of the Compiègne Laboratory of Applied Mathematics (UTC-LMAC) since 2018. With more than 30 personnel – lecturer-cum- research scientists, associate professors, temporary teaching and research attachés (ATER), doctoral and post-doctoral students – UTC-LMAC has two teams. The first, EPIA, is devoted to "inverse problems and numerical analysis"; the second, S2, to "stochastic systems". Currently, 6 lecturer-cumresearch scientists, are mobilised on Coveille, a modelling project linked to the Covid-19 epidemic.

After 15 years as a university professor - 8 years at the engineering school, Ecole Centrale Paris in the laboratory of mathematics applied to systems, followed by an additional 7 years at the École normale supérieure de Cachan in the Centre of mathematics and their Applications - Florian De Vuyst came to UTC in 2017, a year before taking over the direction of UTC-LMAC in January 2018. "Currently, LMAC has 13 lecturer-cum- research scientists, 2 associate professors, 2 ATERs and some 15 PhD students. Within the lab, we work of course on purely theoretical aspects but also on algorithms and more practical applications", explains Florian De Vuyst. As a host team, LMAC is also a member of the Fédération de mathématiques des Hauts-de-France (FMHF), a CNRS research federation.

What are the specialities of the two research teams? "EPIA works on the problems of "inverse problems", "partial differential equations" or "numerical model reduction". Pure deterministic modelling with practical applications in many fields. We can mention the detection of anomalies, medical imaging, fluid mechanics or road traffic, for example. The S2 team is particularly interested in stochastic modelling, characterised by the introduction of randomness, mathematical statistics, data analysis or even machine learning. Theoretical fields which lead to models allowing, among other things, the extraction of knowledge, forecasting under uncertainty, detection of changes in trend, robust estimation, etc. Models applicable, in particular, in the fields of health, physical systems such as mechanics - the study of cracks in a material, for example - the reliability of complex systems, or simply human activity", he stresses.

What can we see as a LMAC's strong point? "It is the existence of two teams, one with a socalled "deterministic" approach, i.e., working on so-called "continuous", homogenised models, and the other with a stochastic approach which is interested in finer samples or scales of time and space. This makes it possible to describe a reality in two different but often complementary ways and to give elements of response in different ways and with different criteria", details Florian De Vuyst. Far from the image of disembodied mathematics, the UTC-LMAC teams collaborate on concrete applications, particularly with health institutions and industry.

"The EPIA team has notably worked with the Amiens University Hospital. The objective was to detect anomalies in the brain or other parts of the body based on the response of living tissue to different types of waves emitted by medical devices. In short, the aim is to reverse the perspective of unintelligible observations or measurements in order to make them intelligible. The team is also collaborating, within the framework of Cifre PhD theses, with the manufacturer Renault on a project to optimise vehicles. A first task related to the problem of making the vehicle lighter while maintaining the same performances or "services". A second, to come, will concern the reduction of drag, i.e., the so-called CX coefficient, due to air friction. This translates into lower energy consumption," he explains.

Finally, LMAC has been involved in collaboration with other UTC laboratories. "A joint collaborative platform has been set up with Adnan Ibrahimbegovic of the UTC-Roberval laboratory and a senior member of the Institut universitaire de France. The aim? To work together on joint projects dedicated to digital mechanics. We are also working with the BMBI, particularly with Anne-Virginie Salsac, on problems related to microcapsules and their transport in blood vessels. The main objective is to enable innovation in medicine. In particular, we have a PhD student under co-supervision who is pursuing a thesis on model reduction techniques", concludes Professor De Vuyst.