The École centrale de Marseille is a leading graduate school of engineering located in Marseille, the second largest city in France. The École centrale de Marseille was created in 2006 by the merging of different previous institutions and has its origins from the École d'ingénieurs de Marseille founded in 1890. It is one of the Centrale Graduate Schools and a member of the TIME network. Wikipedia.
Refregier P.,Ecole Centrale Marseille
Optics Letters | Year: 2012
The irreversible behavior of polarization properties that appears when random unitary transformations are applied to three-dimensional (3D) random optical fields is investigated. The ability of 3D degrees of polarization not to increase and to evolve independently of each other with such transformations is analyzed. © 2012 Optical Society of America.
Brasselet S.,Ecole Centrale Marseille
Advances in Optics and Photonics | Year: 2011
In this tutorial I analyze the polarization-dependent properties of different optical contrasts widely used today in imaging, applied to biology and biomedical diagnostics. I derive the essential properties of the polarization dependence of optical processes such as two-photon fluorescence, nonlinear coherent effects in the nonresonant as well as vibrational-resonant regimes, and analyze how they can be exploited to provide information on the molecular orientational organization in a biological sample. Two examples will be detailed: the first one the measurement of lipid order in artificial and cell membranes by using fluorescent labeling, and the second one structural imaging of collagen in tissues by using second-harmonic generation. © 2009 Optical Society of America.
Scolan Y.-M.,Ecole Centrale Marseille
Journal of Fluids and Structures | Year: 2010
Flip-through is known as a rapidly focusing phenomenon at a wall leading to high loads without impact of liquid. In order to simulate numerically these highly nonlinear waves, the boundary value problem is formulated in potential theory without surface tension. A desingularized technique is used to compute the velocity potential. Conformal mappings of the fluid domain simplify the formulation of the solution.As shown by many contributors to the method of fundamental equations (another name to denote desingularized methods), the suitable desingularizing distance must be chosen with care. Here the criteria for choosing it follow from energy and mass conservation laws. This study shows what is the influence of an arbitrary additive constant to the velocity potential regarding conservation laws. Validation tests are performed on a focused wave. Recommendations are given regarding the choice of the desingularizing distance and the additive constant as well.In order to better control the initiation of flip-through, the simulations start from an initial free surface deformation in a rectangular tank, with or without varying bathymetry. The subsequent jet running along the wall, is described and the corresponding loads are discussed. In particular in the present configuration, it is shown that, along the wall, the maximum acceleration precedes the maximum of pressure contrary to the findings of previous studies. The sensitivity of the results with regard to the shape of the initial deformation and the local bathymetry is discussed. © 2010 Elsevier Ltd.
Martins Afonso M.,Ecole Centrale Marseille
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2014
We investigate the bounds between normal or anomalous effective diffusion for inertial particles transported by parallel flows. The infrared behavior of the fluid kinetic-energy spectrum, i.e., the possible presence of long-range spatiotemporal correlations, is modeled as a power law by means of two parameters, and the problem is studied as a function of these latter. Our results, obtained in the limit of weak relative inertia, extend well-known results for tracers and apply to particles of any mass density, subject to gravity and Brownian diffusion. We consider both steady and time-dependent flows, and cases of both vanishing and finite particle sedimentation. © 2014 American Physical Society.
Molin B.,Ecole Centrale Marseille
Applied Ocean Research | Year: 2011
A hydrodynamic model of perforated or slotted structures is proposed. It is asymptotic in the sense that the openings are supposed to be infinitely small and numerous, and the wall thickness to be nil. At variance with other work, a quadratic, not linear, law, relating the pressure differential to the traversing velocity, is assumed. As a result the hydrodynamic coefficients (added mass and damping) become amplitude dependent. The model is applied to bodies of various shapes including cylinders, plates and disks, in forced motion or submitted to incoming waves. Good agreement with experimental data is generally observed. © 2010 Elsevier Ltd.