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Augmented NETT regularization of inverse problems
Abstract: We propose aNETT (augmented NETwork Tikhonov) regularization as a novel data-driven reconstruction framework for solving inverse problems. An encoder-decoder type network defines a regularizer consisting of a penalty...
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Vector-valued spline method for the spherical multiple-shell electro-magnetoencephalography problem
S Leweke, O Hauk, V Michel
Jul 18, 2022
Abstract Human brain activity is based on electrochemical processes, which can only be measured invasively. Thus, quantities such as magnetic flux density (MEG) or electric...
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Covid-19
In a recent article, we introduced two novel mathematical expressions and a deep learning algorithm for characterizing the dynamics of the number of reported infected cases with SARS-CoV-2. Here, we show that such formulae can...
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Jet noise
An exact analysis of the field radiated by tonal and random non-axisymmetric sources distributed over a disc or cylinder is presented. The analysis is exact, without recourse to near- or far-field approximations, and leads to a...
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Data driven regularization by projection
Abstract: We study linear inverse problems under the premise that the forward operator is not at hand but given indirectly through some input-output training pairs. We demonstrate that regularization by projection and...
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Task adapted reconstruction for inverse problems
The paper considers the problem of performing a task defined on a model parameter that is only observed indirectly through noisy data in an ill-posed inverse problem. A key aspect is to formalize the steps of reconstruction...
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Covid-19
In a recent article, we introduced two novel mathematical expressions and a deep learning algorithm for characterizing the dynamics of the number of reported infected cases with SARS-CoV-2. Here, we show that such formulae can...
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Symmetrization techniques in image deblurring
This paper presents some preconditioning techniques that enhance the performance of iterative regularization methods applied to image deblurring problems determined by a wide variety of point spread functions (PSFs) and boundary...
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Consistency of Bayesian inference with Gaussian process priors in an elliptic inverse problem
M Giordano, R Nickl
Aug 20, 2020
For $\mathcal{O}$ a bounded domain in $\mathbb{R}^d$ and a given smooth function $g:\mathcal{O}\to\mathbb{R}$, we consider the statistical nonlinear inverse problem of recovering the conductivity $f>0$ in the divergence...
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Data driven regularization by projection
A Aspri, Y Korolev, O Scherzer
Jan 28, 2022
We study linear inverse problems under the premise that the forward operator is not at hand but given indirectly through some input-output training pairs. We demonstrate that regularization by projection and variational...
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DEEP IMPORTANCE SAMPLING USING TENSOR TRAINS WITH APPLICATION TO A PRIORI AND A POSTERIORI RARE EVENTS

We propose a deep importance sampling method that is suitable for estimating rare event probabilities in high-dimensional problems. We approximate the optimal importance distribution in a general importance sampling problem...

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Representation and reconstruction of covariance operators in linear inverse problems
Abstract We introduce a framework for the reconstruction and representation of functions in a setting where these objects cannot be directly observed, but only indirect and noisy...
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DEEP IMPORTANCE SAMPLING USING TENSOR TRAINS WITH APPLICATION TO A PRIORI AND A POSTERIORI RARE EVENTS

We propose a deep importance sampling method that is suitable for estimating rare event probabilities in high-dimensional problems. We approximate the optimal importance distribution in a general importance sampling problem...

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Augmented NETT regularization of inverse problems
Abstract: We propose aNETT (augmented NETwork Tikhonov) regularization as a novel data-driven reconstruction framework for solving inverse problems. An encoder-decoder type network defines a regularizer consisting of a penalty...
Published by:
Iteratively Reweighted FGMRES and FLSQR for Sparse Reconstruction

This paper presents two new algorithms to compute sparse solutions of large-scale linear discrete ill-posed problems. The proposed approach consists in constructing a sequence of quadratic problems approximating an `...

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The difficulty of computing stable and accurate neural networks
Deep learning (DL) has had unprecedented success and is now entering scientific computing with full force. However, current DL methods typically suffer from instability, even when universal approximation properties guarantee the...
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A Review of Mathematical and Computational Methods in Cancer Dynamics.
Cancers are complex adaptive diseases regulated by the nonlinear feedback systems between genetic instabilities, environmental signals, cellular protein flows, and gene regulatory networks. Understanding the cybernetics of...
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Jet noise
An exact analysis of the field radiated by tonal and random non-axisymmetric sources distributed over a disc or cylinder is presented. The analysis is exact, without recourse to near- or far-field approximations, and leads to a...
Published by:

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