This work presents the application of the Complex Orthogonal Decomposition (COD) to a given spatio-temporal signal. COD has been introduced first in the article of B. Feeny, entitled "A Complex Orthogonal Decomposition for Wave Motion Analysis", published in the Journal of Sound and Vibration. The purpose of this signal analysis method is to extract spatial and temporal modes out of a signal. This approach is especially suited to deal with oscillatory signals where phase information is important and where spatial forms are unknown. We provide two theoretical chapters presenting the main mathematical concepts behind COD and a series of example (with associated Python scripts) to demonstrate the efficiency of the method and some characteristical features. Codes are to be found on https://github.com/sperrard/pycod .

Link : https://arxiv.org/abs/2604.13084 

We present an image processing method to track and characterize the motion of air–liquid interfaces occurring in aerated liquid baths. In a rectangular tank filled with water, an immersed sparger injects air vertically at a constant flow rate and creates well-defined sloshing oscillations of the free surface. The phenomenon is referred to as self-induced sloshing. We retrieve the positions of both the surface and the jet position using a tailored image processing method based on shadowgraphy. Using Complex Orthogonal Decomposition (COD), we reveal the main spatial and temporal dynamics of the oscillations. 

Link : 10.1016/j.ijmultiphaseflow.2025.105543

The Alkali-Silica Reaction (ASR) is a deleterious concrete chemical reaction that has been studied a lot since its discovery in 1940. An attempt for a statistical model to predict the expansion of concrete based on several parameters is presented. 

This work was done during a 3 months internship in 2021, with NTNU, Norway.

Link : 10.2478/ncr-2022-0003

Poster : 10.13140/RG.2.2.10435.32800

One of the solutions to reduce the environmental impact of the construction sector is the use of alternative materials, more sustainable and with tailored or new properties. This paper proposes the valorization of oyster shell co-products within cementitious materials. These co-products from oyster farm could be used to produce composites with interesting properties.  

Link : 10.1007/978-3-031-21735-7_9