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We provide a rigorous asymptotic method to build approximate conditions equivalent to a thin layer. With these conditions the electromagnetic field may be computed in domains such as a biological cell, without meshing the membrane. The influence of the membrane is replaced by an appropriate condition on the inner domain, while in the thin layer, the approximate field is explicitly known. We give error estimates, which validate our asymptotic method, and we present a few numerical results performed with the finite-element method. Index Terms--Asymptotic methods, finite-element method, thin layers.

The induced currents into the human body by a low-frequency magnetic field are computed using three-dimensional finite elements and a special [PHI]-A formulation. This magnetic field is generated by a real (possibly unknown) power system. The stray field is characterized by an equivalent multipole, fitted from some local measurements of the field, which is a good compromise between accuracy and number of degrees of freedom. The methodology is validated on a test-device using the software FLUX3D Index Terms--Equivalent source, finite-element method, human exposure, inverse problem, low-frequency magnetic stray fields.

This paper deals with some aspects of performance of the symmetric successive over-relaxation preconditioner in a distributed environment. The details of distributed formulation of the preconditioner are presented. Some performance metrics are compared and discussed for the message passing interface implementation of the algorithm. The properties of the solver are estimated for concurrent three-dimensional formulation of the finite-element time-domain method. The analyzed benchmark models are approximated by tetrahedral first order Whitney elements. Index Terms--Edge elements, finite-element (FE) method, iterative solver, parallel numerical algorithms, time-domain algorithm.

Properties of the three-dimensional formulation of the finite element time domain algorithm for the wave equation are analyzed. First-order edge elements are implemented in the formulation. Several issues associated with deformation of the structured mesh and efficiency of the time integration scheme are presented. The convergence and stability of the time domain algorithm depending on the spatial discretization are discussed. The numerical accuracy of the simulation is studied. Index Terms--Edge elements, finite element method, stability, time domain analysis.

A procedure to optimize the specific absorption rate deposed in the patient during oncology hyperthermia treatment is presented. It is based on a genetic algorithm coupled to a finite-element formulation. The optimization procedure is applied to a real human body obtained from computerized tomography scans. Index Terms--Electromagnetic fields, finite-element methods, genetic algorithms, hyperthermia.

An efficient preconditioner for systems issued from the finite element discretization of time harmonic Maxwell's equations with absorbing boundary conditions is presented. It is based on the Helmholtz decomposition of the electromagnetic field and its discrete counterpart. It is compared to a classical preconditioner on both simple and realistic problems. Its behavior is also evaluated on meshes showing different characteristics. Index Terms--Electromagnetic fields, finite-element methods, numerical analysis, scattering.

This paper deals with a distributed time-domain modeling of electromagnetic phenomena with the finite-element method. The model is approximated by edge elements. The constitutive equations and method of parallelization of the algorithm are presented. The properties Of the distributed finite-element time-domain algorithm are discussed. Some typical performance metrics are studied for the parallel versions of the software. The presented algorithm is executed on a heterogeneous and a homogeneous clusters of workstations. Two different distributed memory environments (MPI and PVM) are used to evaluate the efficiency of the algorithm. Index Terms--Distributed computing, edge elements, finite-element time-domain (FETD) algorithm, high-frequency electromagnetic field.

A three-dimensional finite-element formulation to compute induced currents into the human body due to relative low-frequency magnetic field is described. Magnetic source field and induced currents are computed separately, allowing to handle sources due to realistic devices. This method is validated using analytical solutions over a sphere. The limit of validity of the formulation is established. Computations using an accurate model of the human body are presented. Index Terms--Bioelectric phenomena, dosimetry, quasi-static magnetic fields, three-dimensional (3-D) finite-element methods.

We present in this paper a computer-aided education (CAE) package allowing to visualize the magnetostatic field in and around the magnetic circuit of a double-U shaped contactor. The modeling of this device is performed by solving in real time a nonlinear finite-element problem. The implementation of this method is optimized greatly in order to allow to animate field patterns in real time in reaction to any user interaction. An evaluation of the improvements brought by this technique to the learning capabilities of students is presented. Index Terms - Contactors, education, finite-element methods, magnetostatics.