Zobrazeno 1 - 10
of 27
pro vyhledávání: '"Carlos F. Borges"'
Autor:
Carlos F. Borges
Publikováno v:
ACM Transactions on Mathematical Software. 47:1-12
We develop fast and accurate algorithms for evaluating √x 2 +y 2 for two floating-point numbers x and y . Library functions that perform this computation are generally named hypot(x,y). We compare five approaches that we will develop in this articl
Autor:
Carlos F. Borges, Jun Lai
In this work, we consider the problem of reconstructing the shape of a three dimensional impenetrable sound-soft axis-symmetric obstacle from measurements of the scattered field at multiple frequencies. This problem has important applications in loca
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::3d055d4a1a9c437510999bb12f0af3d4
Publikováno v:
SIAM Journal on Scientific Computing. 38:A1770-A1787
We present a fast direct solver for two-dimensional scattering problems, where an incident wave impinges on a penetrable medium with compact support. We represent the scattered field using a volume potential whose kernel is the outgoing Green's funct
Autor:
George Biros, Carlos F. Borges
In this paper, we present algorithms for reconstructing an unknown compact scatterer embedded in a random noisy background medium, given measurements of the scattered field and information about the background medium and the sound profile. We present
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c73be7484914f40858809266fc6822f1
http://arxiv.org/abs/1805.01980
http://arxiv.org/abs/1805.01980
Publikováno v:
Journal of Scientific Computing. 66:917-940
We introduce a preconditioner that can be both constructed and applied using only the ability to apply the underlying operator. Such a preconditioner can be very attractive in scenarios where one has a highly efficient parallel code for applying the
We describe a fast, stable algorithm for the solution of the inverse acoustic scattering problem in two dimensions. Given full aperture far field measurements of the scattered field for multiple angles of incidence, we use Chen's method of recursive
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::34bf156d8be1f45c64c8c9df99ed59cf
http://arxiv.org/abs/1608.06871
http://arxiv.org/abs/1608.06871
Publikováno v:
SIAM Journal on Scientific Computing. 34:B392-B420
We introduce a method for constructing an element-by-element sparse approximate inverse (SAI) preconditioner designed to be effective in a massively parallel spectral element modeling environment involving nonsymmetric systems. This new preconditioni
Autor:
Carlos F. Borges
The article of record as published may be found at: http://dx.doi.org/10.1016/j.amc.2015.01.121 We consider the problem of constructing a polynomial approximation to a function f(x) over the interval [--1; 1] that minimizes the mean squared relative
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ea7bb5ad98b5c32c0eef46354ca8ba3a
https://hdl.handle.net/10945/45492
https://hdl.handle.net/10945/45492
Autor:
Carlos F. Borges, Tim Pastva
Publikováno v:
Computer Aided Geometric Design. 19:275-289
We begin by considering the problem of fitting a single Bezier curve segment to a set of ordered data so that the error is minimized in the total least squares sense. We develop an algorithm for applying the Gauss-Newton method to this problem with a
Autor:
Leslie Greengard, Carlos F. Borges
We consider the problem of reconstructing the shape of an impenetrable sound-soft obstacle from scattering measurements. The input data is assumed to be the far-field pattern generated when a plane wave impinges on an unknown obstacle from one or mor
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::8e93459f1285b9f16ddce0d4026b46fa