UTCS Colloquia: William H. Press/Los Alamos National Laboratory DISCRETE RADON TRANSFORMS EXACT INVERSES AND UNEXPECTED GENERALIZATIONS ACES 6.304 (ICES Seminar Room)

Contact Name: 
Jenna Whitney
Date: 
Oct 5, 2006 3:30pm - 5:00pm


There is a signup schedule for this event.

Type of
Talk: Faculty Candidate

Speaker Name: William H. Press

Spe

aker Affiliation: Los Alamos National Laboratory New Mexico

Date:
October 5 2006

Start Time: 3:30 p.m.

Coffee: 3:00 p.m.

Location (other): ACES 6.304 (ICES Seminar Room)

Host: J Stro

ther Moore and Robert Jansen (crhyink%40cs.utexas.edu)

Talk Title:

DISCRETE RADON TRANSFORMS EXACT INVERSES AND UNEXPECTED GENERALIZATIONS
Talk Abstract:

The familiar Radon transform calculates the pro

jections of
an image at various angles. Its inverse important in comp

uterized
tomography reconstructs the image; this is generally done by discretization of the continuous equations giving an
approximate
result. We show that a certain kind of discrete
Radon transform has a

n exact fast inverse that exactly
reproduces the pixel-by-pixel values
of the original image.
Fourier methods are not used or needed. We al

so show new
generalizations of this transform to operations other than

sums along lines including some that may have novel applications
i

n signal processing.

Speaker Bio:

Bill Press is a Sen

ior Fellow at the Los Alamos National Laboratory
(LANL) in the Statisti

cal Sciences group (Group D-1). His
research is on bioinformatics espe

cially whole genome studies
and statistical methods. Prior to June 20

04 he served
for five years as LANL''s Deputy Laboratory Director for

Science and Technology. Before coming to LANL in 1998 he
was for t

wenty years Professor of Astronomy and Physics
at Harvard University a

nd a member of the Harvard-Smithsonian
Center for Astrophysics.