7 papers · 1 filter
On Fourier Phase Retrieval from Differential Intensity Measurements with Applications to Wavefront Sensing
Simon Hubmer, Lukas Weissinger, Ronny Ramlau +1
In this paper, we consider Fourier phase retrieval from differential intensity measurements, i.e., the problem of determining the phase of a complex-valued function from a series o…
On the Intensity-based Inversion Method for Quantitative Quasi-Static Elastography
Ekaterina Sherina, Simon Hubmer
In this paper, we consider the intensity-based inversion method (IIM) for quantitative material parameter estimation in quasi-static elastography. In particular, we consider the pr…
A Geometrical Acoustics based Focusing Algorithm for Layered Media in Medical Ultrasound
Simon Hackl, Simon Hubmer, Ronny Ramlau
Ultrasound imaging is a widely used, non-invasive diagnostic tool in modern medicine. A crucial assumption is a constant sound speed in the observed medium. For large scale sound s…
On Phase Unwrapping via Digital Wavefront Sensors
Simon Hubmer, Victoria Laidlaw, Ronny Ramlau +2
In this paper, we derive a new class of methods for the classic 2D phase unwrapping problem of recovering a phase function from its wrapped form. For this, we consider the wrapped…
On SCD Semismooth Newton methods for the efficient minimization of Tikhonov functionals with non-smooth and non-convex penalties
Helmut Gfrerer, Simon Hubmer, Ronny Ramlau
We consider the efficient numerical minimization of Tikhonov functionals with nonlinear operators and non-smooth and non-convex penalty terms, which appear for example in variation…
An Inverse Problems Approach to Pulse Wave Analysis in the Human Brain
Lukas Weissinger, Simon Hubmer, Ronny Ramlau +1
Cardiac pulsations in the human brain have received recent interest due to their possible role in the pathogenesis of neurodegenerative diseases. Further interest stems from their…