This paper is the written version of the SECED evening talk given at the ICE by the first author on 29 November 2017. It presents numerical analyses related to the seismic response of earth dams. A well-documented case study is... more
Dans ce papier on s'intéresse à une approximation par éléments finis d'un model de Koiter pour des coques linéairement élastiques de surface moyenne peu régulière. Afin de considérer une approximation conforme nous proposons une... more
The number and type of boundary conditions to be used in the numerical modeling of fluid mechanics problems is normally chosen according to a simplified analysis of the characteristics, and also from the experience of the modeler. The... more
A plane wave incident perpendicular to one open end of a conductive tube, as part of a honeycomb-structure, is attenuated on its way through it. In order to calculate its total attenuation for various frequencies the FE-method will be... more
We discuss boundary value problems for the characteristic stationary von Neumann equation (stationary sigma equation) and the stationary Wigner equation in a single spatial dimension. The two equations are related by a Fourier transform... more
A thorough numerical assessment of Finite Difference Time Domain and Complex-Envelope Alternating-Direction-Implicit Finite-Difference-Time-Domain Methods has been carried out based on a basic single mode Plane Optical Waveguide... more
In a paper on "the Brownian motion analog of the well-known Milne problem in radiative transfer theory" [J Stat Phys 25 (1981) 569-82], Burschka and Titulaer reported: "The value we find for this 'Milne extrapolation length' is, in the... more
A discretization scheme for nonnegative diffusion processes is proposed and the convergence of the corresponding sequence of approximate processes is proved using the martingale problem framework. Motivations for this scheme come... more
On the one hand the heterogeneity of the circulatory system requires the use of different models in its different compartments, featuring different assumptions on the spatial degrees of freedom. On the other hand, the mutual interactions... more
Complex media have gained interest in microwave and millimeter-wave devices. They display some interesting characteristics such as, for instance, tunability and controlled filtering capacity. However, such media are generally very complex... more
In a previous study [5] we investigate the bound states of the Hamiltonian describing a quantum particle living on three dimensional straight strip of width d. We impose the Neumann boundary condition on a disc window of radius a and... more
A numerical method is derived for obtaining the solution to the 2.5D scalar Helmholtz equation involving an arbitrary 2D lossless inhomogeneous dielectric scatterer excited by a point source in a closed waveguide. The spectral Lanczos... more
This paper provides an overview of the recent developments of finite-volume techniques for time-domain electromagnetic simulations. The distinctive characteristic of Finite-Volume Time-Domain (FVTD) algorithms is their applicability in... more
A novel anisotropic-medium perfectly matched layer (PML) implementation is presented for boundary truncation in the three-dimensional vector finite-element time-domain (FETD) method. This approach utilizes a complex set of vector test and... more
An interior penalty discontinuous Galerkin method is described with a conformal perfectly matched layer (PML) for solving the two first-order Maxwell's equations in the time domain. Both central and upwind fluxes are studied in this work.... more
This paper presents a new method for solving two-dimensional wave problems in infinite domains. The method yields a solution that satisfies Sommerfeld's radiation condition, as required for the correct solution of infinite domains excited... more
Starting from classical absorbing boundary conditions, we propose a method for the separation of time-dependent scattered wave fields due to multiple sources or obstacles. In contrast to previous techniques, our method is local in space... more
The paper presents an efficient method for the design of printed microstrip circuit with packaging in mind, referred to as numerical prepackaging with a Perfectly Magnetic Conductive (PMC) lid. The method comprises making the design... more
A plane wave incident perpendicular to one open end of a conductive tube, as part of a honeycomb-structure, is attenuated on its way through it. In order to calculate its total attenuation for various frequencies the FE-method will be... more
In this paper, the use of an absorbing boundary condition (ABC) is investigated for the numerical simulation of free surface water waves. An enhanced type of an ABC based on the rstand second-order Higdon boundary conditions [1] is... more
─ Reflections from boundaries of the FDTD computational domain lead to inaccurate, even unstable codes when dealing with problems involving double negative (DNG) materials. Here, an efficient and simple algorithm is presented for... more
The purpose of this paper is the study of a stable method for coupling two types of schemes using or not numerical fluxes for the resolution of Maxwell's equations in time domain. The methods considered in the hybridization process... more
We exhibit a scaling law for the criticalSISstochastic epidemic. If at time 0 the population consists ofinfected andsusceptible individuals, then when the time and the number currently infected are both scaled by, the resulting process... more
In this article, we present a finite element method for studying the dynamic behavior of deformable vesicles, which mimic red blood cells, in a non-Newtonian Casson fluid. The fluid membrane, represented by an implicit level-set function,... more
This letter describes the implementation of second-order one-way wave-equation absorbing boundary conditions (ABCs) in two unconditionally stable finite-difference time-domain (FDTD) methods-namely the locally one-dimensional (LOD)-and... more
Wave propagation through rapidly but continuously varying media is surprisingly subtle, and in a pair of recent papers [
A set of two-dimensional (2D) electromagnetic (EM) MATLAB codes, using both fi rst-order coupled differential (Maxwell) equations and second-order decoupled (wave) equations, are developed for both transverse-magnetic (TM) and... more
In this review paper, the solution of lossy inhomogeneous scattering problems is considered. The solution is given in terms of the transverse field components rather than the axial components. In order to terminate the edge element mesh,... more
An Absorbing Boundary Condition (ABC) for FDTD simulations based on the concept of surface impedance boundary, which is referred to as Surface Impedance Absorbing Boundary Condition (SIABC), is proposed in this paper. It is extremely easy... more
In this work we study uniform error bounds for approximations of the ruin probability in a mixed poisson model with lattice claim amounts. The approximations considered are constructed by rounding the record lows up, down or to the... more
The solution of the Maxwell's equations by means of the finite time domain difference method (FDTD) is used to describe the propagation of the electromagnetic field [1]. The method consists of transferring the differential equations of... more
The finite-difference time-domain (FDTD) method is used to investigate the effects of highly lossy grounds and the frequency-band selection on ground-penetrating-radar (GPR) signals. The ground is modeled as a heterogeneous half space... more
We study the approximation of stochastic integrals in the Itô sense. We establish the exact convergence rate of the minimal errors that can be achieved by arbitrary algorithms based on a finite number of observations of the Brownian... more
and circular structures with a rectangular type of corrugation, with and without the presence of a second Ž. smooth or corrugated conductor. 2. The exact analytic static-field solutions and Green's functions of all of these structures... more
Measured equation of invariance in the time domain (TD-MEI) has been used as an FDTD-ABC. The TD-MEI coefficients, are derived using a new technique named "self metron". Unlike the traditional MEI, in this technique there is no need to... more
A recursive matrix scheme was developed to calculate reflection and transmission coefficients for electromagnetic plane waves incident on a stratified medium composed of bianisotropic media. The recursive character of the scheme avoids... more
We derive periodic multilayer absorbers with effective uniaxial properties similar to perfectly matched layers (PML). This approximate representation of PML is based on the effective medium theory and we call it an effective medium PML.... more
A boundary method for computing unsteady wave propagation in three-dimensional space is proposed. The described approach is based on the method of difference potentials and the Huygens principle, which makes it possible to update the... more
Local artificial boundary conditions (ABCs) for the numerical simulation of waves have been successfully used for decades (most notably, the boundary conditions due to Engquist & Majda, Bayliss, Gunzburger & Turkel, and Higdon). The basic... more
We describe a high-order accurate methodology for the numerical simulation of time-harmonic waves governed by the Helmholtz equation. Our approach combines compact finite difference schemes that provide an inexpensive venue toward... more
A gradual long-time growth of the solution in perfectly matched layers (PMLs) has been previously reported in the literature. This undesirable phenomenon may hamper the performance of the layer, which is designed to truncate the... more
The number and type of boundary conditions to be used in the numerical modeling of fluid mechanics problems is normally chosen according to a simplified analysis of the characteristics, and also from the experience of the modeler. The... more
In electromagnetic compatibility, scattering problems are defined in an infinite spatial domain, while numerical techniques such as finite element methods require a computational domain that is bounded. The perfectly matched layer (PML)... more