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Anatomical realistic voxel models of human beings are commonly used in numerical dosimetry to evaluate the human exposure to low-frequency electromagnetic fields. The downside of these models is that they do not correctly reproduce the boundaries of curved surfaces. The stair-casing approximation errors introduce computational artifacts in the evaluation of the induced electric field and the use of post-processing filtering methods is essential to mitigate these errors. With a suitable exposure scenario, this paper shows that tetrahedral meshes make it possible to remove stair-casing errors. However, using tetrahedral meshes is not a sufficient condition to completely remove artifacts, because the quality of the tetrahedral mesh plays an important role. The analyses carried out show that in real exposure scenarios, other sources of artifacts cause peak values of the induced electric field even with regular meshes. In these cases, the adoption of filtering techniques cannot be avoided. [ABSTRACT FROM AUTHOR]

Computation of the internal electric field induced in the human body by low-frequency power systems is time-consuming. We compute an approximate solution in nearly real time by using a reduced basis for the internal field. The basis is computed once (off-line) by approximating the source by multipoles, the coefficients of which can be computed for any position of the human body due to analytic translation and rotation formulas. The results are validated with respect of finite element method (FEM) computation. [ABSTRACT FROM AUTHOR]

In this work we present two dual finite element formulations to compute extremely low frequency (ELF) induced fields into the human body. This allows to estimate the numerical error, as well as rigorously bound the (global) co-energy. This method is herein applied to the classical case of the exposure to a homogeneous magnetic field, and to the field generated by an infinite wire. [ABSTRACT FROM PUBLISHER]

We computed by finite element the fields induced in an heterogeneous model of the human body by both the electric and magnetic field generated by a three-phase power line. Results were partially validated and analyzed by comparison with existing data with uniform magnetic field. Induced currents due to both E and B were developed inside the body in an asymmetrical manner. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new dynamical model of tissue electroporation. The model is based on equivalent circuit approach at the tissue. Considering two current densities from cells and extracellular matrix, we identify the macroscopic homogenised contribution of the cell membranes. Our approach makes it possible to define a macroscopic homogenised electric field and a macroscopic homogenised transmembrane potential. This provides a direct link between the cell scale electroporation models and the tissue models. Finite element method adapted to the new non-linear model of tissue electroporation is used to compare experiments with simulations. Adapting the phenomenological electroporation model of Leguèbe et al. to the tissue scale, we calibrate the tissue model with experimental data. This makes two steps appear in the tissue electroporation process, as for cells. The new insight of the model lies in the well-established equivalent circuit approach to provide a homogenised version of cell scale models. Our approach is tightly linked to numerical homogenisation strategies adapted to bioelectrical tissue modeling. [ABSTRACT FROM AUTHOR]