Our new short film series 'Show Me the Maths' doesn't beat about the mathematical bush. It gets right down to it. Down, that is, to the maths, in all its crucial, complex, sometimes incomprehensible (even to other mathematicians, so you say) guises.
The series will feature research in Number Theory, Mathematical Biology and the History of Mathematics, amongst others. If you want to join in let me (Dyrol) know.
Consistent learned reconstruction from limited angle data in Photoacoustic Tomography
Please note this seminar taking place at RAL - Rutherford Appleton Laboratory, near Didcot
Abstract
Joint work with Bolin Pan
In photoacoustic tomography (PAT) with flat sensor, we routinely encounter two types of limited data. The first is due to using a finite sensor and is especially perceptible if the region of interest is large relatively to the sensor or located farther away from the sensor. In this talk we focus on the second type caused by a varying sensitivity of the sensor to the incoming wavefront direction which can be modelled as binary i.e. by a cone of sensitivity. Such visibility conditions result, in Fourier domain, in a restriction of the data to a bowtie, akin to the one corresponding to the range of the forward operator but further narrowed according to the angle of sensitivity.
We show how we can separate the visible and invisible wavefront directions in PAT image and data using a directional frame like Curvelets, and how such decomposition allows for decoupling of the reconstruction involving application of expensive forward/adjoint solvers from the training problem. We present fast and stable approximate Fourier domain forward and adjoint operators for reconstruction of the visible coefficients for such limited angle problem and a tailored UNet matching both the multi-scale Curvelet decomposition and the partition into the visible/invisible directions for learning the invisible coefficients from a training set of similar data.
The University's Chief Diversity Officer, Professor Tim Soutphommasane, is hosting an Open Forum for staff to which everyone is welcome.
The forum will take place on Thursday 8 February from 11am to 12.15pm, at the H.B. Allen Centre on Banbury Road. This Open Forum will be recorded and the link will be made available shortly after the event.
The event will also be streamed online.
In addition to resolution support being developed centrally by the HR Business Partners team, the MPLS Resolution Service, led by trained facilitators from within the Division, is now up and running and offering early intervention and impartial mediation support for colleagues experiencing conflict in the workplace.