Seminar 8th December 2014 1 p.m. 177/2011
Non-linear models for x-ray computed tomography reconstruction
Dr Thomas Blumensath
University of Southampton
- Categories
- NGCM
- Submitter
- Susanne Ufermann Fangohr
Modelling non-linear effects on x-ray transmission through an engine block.
Summary
Non-linear system theory is an important tool in many areas of engineering. Whether we want to accurately model and understand noise produced by jet engines or produce accurate three-dimensional images of internal organs using x-ray tomography, taking account of non-linear effects is often crucial.
In this project you will study different mathematical models that can be used to describe non-linear systems. You will focus particularly on the problem of model inversion, that is, for a known model, if you observe the output of the model, can you develop computational methods that allow you to compute the original model input? To help with this inversion, additional information on the input of the system will be assumed. This information will be formulated using sparse models, which have recently revolutionised several areas of science and engineering.
As a potential application, you will study the problem of x-ray tomography. Here the system you will model and invert describes the transmission of x-ray photons through an object (such as the human body). This mathematical model will describe non-linear effects found in most x-ray systems. By developing new computer algorithms to invert the non-linear model, you will design new methods that are able to produce better and more accurate images of the internal structure of an object. An important part of your work will be in the design of algorithms that can model and exploit additional image structure.
Bio
Thomas Blumensath received a B.Sc. (Hons) in Music Technology and Audio System Design from the University in Derby in 2002 and, in 2006, a PhD in Electronic Engineering (Bayesian Signal Processing) from the University of London. Since 2005, he held various appointments as Postdoctoral Researcher and Research Fellow working at the Centre for Digital Music at Queen Mary University of London, the Institute for Digital Communications at the University of Edinburgh, the Applied Mathematics Research Group at the University of Southampton and the University of Oxford's Centre for functional MRI of the brain.
In 2012 he joined the Institute of Sound and Vibration Research at the University of Southampton, where he currently holds a tenure track career development fellowship. As an engineer and mathematician, he is working on fundamental signal and image processing techniques and their application to a range of scientific problems. Based on a sound mathematical basis, his research aims at the development of advanced methods in signal and image processing and their application to challenging problems in the physical and life sciences. He is particularly interested in x-ray image reconstruction, biomedical applications and human brain mapping.