BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Memento EPFL//
BEGIN:VEVENT
SUMMARY:NONREFLECTING BOUNDARY CONDITIONS FOR TIME-DEPENDENT WAVE PROPAGAT
 ION
DTSTART:20101013T161500
DTSTAMP:20260509T211718Z
UID:c0e0cc9fb0745223874360caf7e2ca93574c4f9fb22df43cbea7c5b1
CATEGORIES:Conferences - Seminars
DESCRIPTION:Dr. Imbo Sim\nThe constant demand for increasingly accurate\, 
 efficient\, and robust numerical methods\, which can handle acoustic\, ela
 stodynamic and electromagnetic wave propagations in unbouded domains\, spu
 rs the search for improvements in artificial boundary conditions. In the l
 ast decade\, the perfectly matched layer (PML) approach has proved a flexi
 ble and accurate method for the simulation of waves in unbounded media. St
 andard PML formulations\, however\, usually require wave equations stated 
 in their standard second-order form to be reformulated as firstorder syste
 ms\, thereby introducing many additional unknowns. To circumvent this cumb
 ersome and somewhat expensive step we propose instead a simple PML formula
 tion directly in its second-order form in 3D. Our formulation requires few
 er auxiliary unknowns than previous formulations. Starting from a high-ord
 er local nonreflecting boundary condition (NRBC) for single scattering\, w
 e derive a local NRBC for time-dependent multiple scattering problems\, wh
 ich is completely local both in space and time. To do so\, we first develo
 p a high order exterior evaluation formula for a purely outgoing wave fiel
 d\, given its values and those of certain auxiliary functions needed for t
 he local NRBC on the artificial boundary. By combining that evaluation for
 mula with the decomposition of the total scattered field into purely outgo
 ing contributions\, we obtain the first exact\, completely local\, NRBC fo
 r time-dependent multiple scattering. The accuracy\, stability and efficie
 ncy of this new local NRBC is evaluated by coupling it to standard finite 
 element or finite difference methods.
LOCATION:MAA110
STATUS:CONFIRMED
END:VEVENT
END:VCALENDAR