Events for 08/31/2016 from all calendars

Numerical Analysis Seminar

Time: 3:00PM - 4:00PM

Location: BLOC 628

Speaker: Carlos Jerez Hanckes, Pontificia Universidad Cat'olica de Chile

Title: Wave Diffraction by Random Shape Scatterers: Uncertainty Quantification by Sparse Tensor Approximation

Abstract: For time-harmonic scattering of electromagnetic waves from scatterers with uncertain geometry, we perform a domain perturbation analysis. Assuming known statistics of the (small amplitude) random perturbations of the scatterers’ (assumed known) nominal geometry, we derive a tensorized integral equation which describes, to leading order, the second order statistics (ie., the two-point correlation) of the random scattered electric field. Both, perfectly conducting as well as homogeneous dielectric scatterers with random boundary (resp. random interface) are considered. Deterministic tensor equations for second-order statistics of both, Cauchy data on the nominal domain of the scatterer as well as of the far-field pattern are derived, generalizing to electromagnetics and to interface problems. The tensorized integral equations are boundary integral equations (BIEs) which are formulated on the nominal scatterer (whose geometry is assumed to be known). Sparse tensor Galerkin discretizations of these BIEs are proposed and analyzed; we show that they allow consistent Galerkin approximations of the complete second order statistics of the random scattered electric field, with computational work equivalent to that for the Galerkin solution of the nominal problem up to logarithmic terms.

First Year Graduate Student Seminar

Time: 5:30PM - 6:30PM

Location: BLOC 628

Speaker: Peter Howard

Title: Goals of the FYGSS; Program information; Applying for fellowships.