6 research outputs found
Numerical Solution of the Monodomain Equation: an Inverse Problem for Infarction Models
This project deals with the finite element approximation of an inverse problem for the monodomain equation, which models the propagation of the electrical potential in the cardiac muscle. The goal consists in recovering the shape of an infarcted area inside the cardiac muscle by measuring the electrical potential at the border of the domain, which is the principle of electrocardiograms (ECG). We consider a problem in two dimensions with implementations in FreeFem++
Digital Phase Reconstruction via Iterative Solutions of Transport-of-Intensity Equation
We develop a variational algorithm for reconstructing phase objects from a series of bright field micrographs. Our mathematical model is based on the transport-of-intensity equation (TIE), which links the phase of a complex field to the axial derivative of its intensity. To reduce reconstruction artifacts, we formulate TIE in a regularized fashion by introducing a family of penalty functionals based on the eigenvalues of the structure tensor. To solve the arising optimization problem, we propose an algorithm based on the alternating direction method of multipliers (ADMM). We apply our method on simulated data and illustrate improved performance compared to the conventional methods such as Tikhonov and total variation (TV) regularizations. We further demonstrate the applicability of the proposed approach by applying it to experimentally-acquired bright field data
¿Cómo Naachtun se volvió una capital regional mediante edificios públicos y mano de obra?
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Space and time resolved measurement of surface magnetic field in high intensity short pulse laser matter interactions
Space and time resolved measurement of surface magnetic field in high intensity short pulse laser matter interactions
Magnetic fields produced by the interaction of intense laser beams on the surface of flat solid targets have been characterized. Laser probe polarimetry diagnosed the spatial and temporal evolution of magnetic field by measuring the changes in the probe beam polarization due to Cotton-Mouton and Faraday effects at different times in respect to a pump laser pulse. Results show that 1 ps after the interaction of the pump laser with the target, a magnetic field of the order of a few MG is already present over a region ≈ 150 µm in diameter centered around the interaction spot. From the spatial and temporal evolutions of the magnetic field, we infer information on the resistivity of the material, showing evidence of a strongly magnetized resistivity.Implementation of activities described in the Roadmap to Fusion during Horizon 2020 through a Joint programme of the members of the EUROfusion consortiu