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Related papers: Describing the Uncertainties in VLBI Images

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Very Long Baseline Interferometric (VLBI) observations of quasar jets enable one to measure many theoretically expected effects. Estimating the significance of observational findings is complicated by the correlated noise in the image…

Instrumentation and Methods for Astrophysics · Physics 2018-10-22 I. N. Pashchenko

Context: Phase referencing is a standard calibration technique in radio interferometry, particularly suited for the detection of weak sources close to the sensitivity limits of the interferometers. However, effects from a changing…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 I. Marti-Vidal , E. Ros , M. A. Perez Torres , J. C. Guirado , S. Jimenez-Monferrer , J. M. Marcaide

Inverse problems play a key role in modern image/signal processing methods. However, since they are generally ill-conditioned or ill-posed due to lack of observations, their solutions may have significant intrinsic uncertainty. Analysing…

Signal Processing · Electrical Eng. & Systems 2019-09-09 Xiaohao Cai , Marcelo Pereyra , Jason D. McEwen

Very long baseline interferometry (VLBI) is a technique for imaging celestial radio emissions by simultaneously observing a source from telescopes distributed across Earth. The challenges in reconstructing images from fine angular…

Instrumentation and Methods for Astrophysics · Physics 2016-11-08 Katherine L. Bouman , Michael D. Johnson , Daniel Zoran , Vincent L. Fish , Sheperd S. Doeleman , William T. Freeman

In complex physical process characterization, such as the measurement of the regression rate for solid hybrid rocket fuels, where both the observation data and the model used have uncertainties originating from multiple sources, combining…

Machine Learning · Computer Science 2023-03-21 Georgios Georgalis , Kolos Retfalvi , Paul E. DesJardin , Abani Patra

Image reconstruction in very-long baseline interferometry operates under severely sparse aperture coverage with calibration challenges from both the participating instruments and propagation medium, which introduce the risk of biases and…

Instrumentation and Methods for Astrophysics · Physics 2026-01-14 Samuel Lai , Nithyanandan Thyagarajan , O. Ivy Wong , Foivos Diakogiannis

Computational molecular modeling and visualization has seen significant progress in recent years with sev- eral molecular modeling and visualization software systems in use today. Nevertheless the molecular biology community lacks…

Computational Engineering, Finance, and Science · Computer Science 2016-05-20 Muhibur Rasheed , Nathan Clement , Abhishek Bhowmick , Chandrajit Bajaj

Computational image reconstruction algorithms generally produce a single image without any measure of uncertainty or confidence. Regularized Maximum Likelihood (RML) and feed-forward deep learning approaches for inverse problems typically…

Machine Learning · Computer Science 2020-12-18 He Sun , Katherine L. Bouman

We develop two algorithms, based on maximum likelihood (ML) inference, for estimating the parameters of polarized radio sources which emit at a single rotation measure (RM), e.g., pulsars. These algorithms incorporate the flux density…

Instrumentation and Methods for Astrophysics · Physics 2017-10-25 D. H. F. M. Schnitzeler , K. J. Lee

Introducing accelerated reconstruction algorithms into clinical settings requires measures of uncertainty quantification that accurately assess the relevant uncertainty introduced by the reconstruction algorithm. Many currently deployed…

Image and Video Processing · Electrical Eng. & Systems 2025-08-12 Luca L. C. Trautmann , Peter A. Wijeratne , Itamar Ronen , Ivor J. A. Simpson

Interplanetary scintillation (IPS) provides an approach for identifying the presence of sub-arcsec structures in radio sources, and very long baseline interferometry (VLBI) technique can help verify whether the IPS sources have fine…

Astrophysics of Galaxies · Physics 2021-10-27 Sumit Jaiswal , Tao An , Ailing Wang , Steven Tingay

Self-calibration methods with the CLEAN algorithm have been widely employed in Very Long Baseline Interferometry (VLBI) data processing in order to correct antenna-based amplitude and phase corruptions present in the data. However, human…

Instrumentation and Methods for Astrophysics · Physics 2024-10-02 Jong-Seo Kim , Aleksei S. Nikonov , Jakob Roth , Torsten A. Ensslin , Michael Janssen , Philipp Arras , Hendrik Mueller , Andrei P. Lobanov

Measuring uncertainties in the output of a deep learning method is useful in several ways, such as in assisting with interpretation of the outputs, helping build confidence with end users, and for improving the training and performance of…

Machine Learning · Computer Science 2022-09-20 Luke Whitbread , Mark Jenkinson

This paper explores optimal methods for obtaining one-dimensional (1D) powder pattern intensities from two-dimensional (2D) planar detectors with good estimates of their standard deviations. We describe methods to estimate uncertainties…

Materials Science · Physics 2014-09-12 Xiaohao Yang , Pavol Juhas , Simon J. L. Billinge

Many of the compact extragalactic radio sources that are used as fiducial points to define the celestial reference frame are known to have proper motions detectable with long-term geodetic/astrometric Very Long Baseline Interferometry…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-16 A. Moór , S. Frey , S. B. Lambert , O. Titov , J. Bakos

Uncertainty estimation, which provides a means of building explainable neural networks for medical imaging applications, have mostly been studied for single deep learning models that focus on a specific task. In this paper, we propose a…

Computer Vision and Pattern Recognition · Computer Science 2023-10-02 Leonhard F. Feiner , Martin J. Menten , Kerstin Hammernik , Paul Hager , Wenqi Huang , Daniel Rueckert , Rickmer F. Braren , Georgios Kaissis

Context: To investigate the differences between positions, as determined by optical (direct imaging) and Very Long Baseline Interferometry (VLBI) techniques, of extragalactic sources listed in the second realization of the International…

Astrophysics of Galaxies · Physics 2015-05-28 J. I. B. Camargo , A. H. Andrei , M. Assafin , R. Vieira-Martins , D. N. da Silva Neto

We propose a probabilistic framework for performing simultaneous estimation of source structure and fringe-fitting parameters in Very Long Baseline Interferometry (VLBI) observations. As a first step, we demonstrate this technique through…

Instrumentation and Methods for Astrophysics · Physics 2020-06-10 Iniyan Natarajan , Roger Deane , Ilse van Bemmel , Huib Jan van Langevelde , Des Small , Mark Kettenis , Zsolt Paragi , Oleg Smirnov , Arpad Szomoru

Reconstructing an image from sparsely sampled Fourier data is an ill-posed inverse problem that occurs in a variety of subjects within science, including the data analysis for Very Long Baseline Interferometry (VLBI) and the…

Instrumentation and Methods for Astrophysics · Physics 2024-01-22 Hendrik Müller , Paolo Massa , Alejandro Mus , Jong-Seo Kim , Emma Perracchione

Large language models (LLMs) often generate fluent but factually incorrect outputs, known as hallucinations, which undermine their reliability in real-world applications. While uncertainty estimation has emerged as a promising strategy for…

Machine Learning · Computer Science 2025-05-13 Pei-Fu Guo , Yun-Da Tsai , Shou-De Lin
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