51 citations · 259 across the 38 of their papers we have counts for
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Error Estimates for Arnoldo-Tikhonov Regularization for Ill-Posed Operator Equations
Ronny Ramlau, Lothar Reichel
Most of the literature on the solution of linear ill-posed operator equations, or their discretization, focuses only on the infinite-dimensional setting or only on the solution of…
On the singular value decomposition of n-fold integration operators
Ronny Ramlau, Christoph Koutschan, Bernd Hofmann
In theory and practice of inverse problems, linear operator equations with compact linear forward operators having a non-closed range and mapping betwee…
Real-time Adaptive Optics with pyramid wavefront sensors: A theoretical analysis of the pyramid sensor model
Victoria Hutterer, Ronny Ramlau, Iuliia Shatokhina
We consider the mathematical background of the wavefront sensor type that is widely used in Adaptive Optics systems for astronomy, microscopy, and ophthalmology. The theoretical an…
Real-time Adaptive Optics with pyramid wavefront sensors: Accurate wavefront reconstruction using iterative methods
Victoria Hutterer, Ronny Ramlau, Iuliia Shatokhina
In this paper, we address the inverse problem of fast, stable, and high-quality wavefront reconstruction from pyramid wavefront sensor data for Adaptive Optics systems on Extremely…
A Conjugate-Gradient Approach to the Parameter Estimation Problem of Magnetic Resonance Advection Imaging
Simon Hubmer, Andreas Neubauer, Ronny Ramlau +1
We consider the inverse problem of estimating the spatially varying pulse wave velocity in blood vessels in the brain from dynamic MRI data, as it appears in the recently proposed…
Non-linear wavefront reconstruction methods for pyramid sensors using Landweber and Landweber-Kaczmarz iteration
Victoria Hutterer, Ronny Ramlau
Accurate and robust wavefront reconstruction methods for pyramid wavefront sensors are in high demand as these sensors are planned to be part of many instruments currently under de…
The MICADO first light imager for the ELT: overview, operation, simulation
Richard Davies, João Alves, Yann Clénet +98
MICADO will enable the ELT to perform diffraction limited near-infrared observations at first light. The instrument's capabilities focus on imaging (including astrometric and high…
Nesterov's Accelerated Gradient Method for Nonlinear Ill-Posed Problems with a Locally Convex Residual Functional
Simon Hubmer, Ronny Ramlau
In this paper, we consider Nesterov's Accelerated Gradient method for solving Nonlinear Inverse and Ill-Posed Problems. Known to be a fast gradient-based iterative method for solvi…