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Related papers: Imprecise k-space sampling and central brightening

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Current and future generations of intensity mapping surveys promise dramatic improvements in our understanding of galaxy evolution and large-scale structure. An intensity map provides a census of the cumulative emission from all galaxies in…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-05 Trevor M. Oxholm , Eric R. Switzer

One of the key approximations to range simulation is downscaling the image, dictated by the natural trigonometric relationships that arise due to long-distance viewing. It is well-known that standard downsampling applied to an image without…

Signal Processing · Electrical Eng. & Systems 2025-05-12 Suayb S. Arslan , Lukas Vogelsang , Michal Fux , Pawan Sinha

Superresolution theory and techniques seek to recover signals from samples in the presence of blur and noise. Discrete image registration can be an approach to fuse information from different sets of samples of the same signal. Quantization…

Computer Vision and Pattern Recognition · Computer Science 2024-12-16 Serap A. Savari

Surveys with a narrow field-of-view can play an important role in probing cosmology, but inferences from these surveys suffer from large sample variance, arising from random fluctuations around the cosmic mean. The standard method for…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-29 Peter Espenshade , Jaiyul Yoo

We study cosmic variance in deep high redshift surveys and its influence on the determination of the luminosity function for high redshift galaxies. For several survey geometries relevant for HST and JWST instruments, we characterize the…

Astrophysics · Physics 2020-07-28 M. Trenti , M. Stiavelli

(abridged) Imaging observations are generally affected by a fluctuating background of speckles, a particular problem when detecting faint stellar companions at small angular separations. Knowing the distribution of the speckle intensities…

Astrophysics · Physics 2009-11-13 Michael P. Fitzgerald , James R. Graham

An innovative inverse scattering (IS) method is proposed for the quantitative imaging of pixel-sparse scatterers buried within a lossy half-space. On the one hand, such an approach leverages on the wide-band nature of ground penetrating…

Information Theory · Computer Science 2021-08-04 Marco Salucci , Nicola Anselmi

Purpose: Interpretability is essential for the clinical adoption of state-of-the-art machine learning (ML) methods in magnetic resonance imaging (MRI). Conventional evaluation of ML reconstructions relies heavily on aggregate image metrics…

In Fourier-based medical imaging, sampling below the Nyquist rate results in an underdetermined system, in which linear reconstructions will exhibit artifacts. Another consequence of under-sampling is lower signal to noise ratio (SNR) due…

Computer Vision and Pattern Recognition · Computer Science 2016-10-04 Patrick Virtue , Michael Lustig

Common ISAR radar images and signals can be reconstructed from much fewer samples than the sampling theorem requires since they are usually sparse. Unavailable randomly positioned samples can result from heavily corrupted parts of the…

Information Theory · Computer Science 2016-11-17 Ljubisa Stankovic

The phenomenon of cosmic shear, or distortion of images of distant sources unaccompanied by magnification, is an effective way of probing the content and state of the foreground Universe, because light rays do not have to pass through mass…

Astrophysics · Physics 2009-11-13 Richard Lieu

We have observed four massive galaxy clusters with the SPIRE instrument on the Herschel Space Observatory and measure a deficit of surface brightness within their central region after subtracting sources. We simulate the effects of…

Task-adapted compressed sensing magnetic resonance imaging (CS-MRI) is emerging to address the specific demands of downstream clinical tasks with significantly fewer k-space measurements than required by Nyquist sampling. However, existing…

Machine Learning · Computer Science 2026-04-15 Xinyu Peng , Ziyang Zheng , Wenrui Dai , Duoduo Xue , Shaohui Li , Chenglin Li , Junni Zou , Hongkai Xiong

Motion artifacts are a common occurrence in the Magnetic Resonance Imaging (MRI) exam. Motion during acquisition has a profound impact on workflow efficiency, often requiring a repeat of sequences. Furthermore, motion artifacts may escape…

Image and Video Processing · Electrical Eng. & Systems 2021-03-16 Mohammad Reza Mohebbian , Ekta Walia , Khan A. Wahid

Purpose: A fast data-driven optimization approach, named bias-accelerated subset selection (BASS), is proposed for learning efficacious sampling patterns (SPs) with the purpose of reducing scan time in large-dimensional parallel MRI.…

Signal Processing · Electrical Eng. & Systems 2020-11-05 Marcelo V. W. Zibetti , Gabor T. Herman , Ravinder R. Regatte

Bayesian Image-on-Scalar Regression (ISR) provides flexible, uncertainty-aware neuroimaging analysis. However, applying ISR to large-scale datasets such as the UK Biobank is challenging due to intensive computational demands and the need to…

Applications · Statistics 2026-02-09 Yuliang Xu , Timothy D. Johnson , Thomas E. Nichols , Jian Kang

Weak lensing mass-mapping is a useful tool to access the full distribution of dark matter on the sky, but because of intrinsic galaxy ellipticies and finite fields/missing data, the recovery of dark matter maps constitutes a challenging…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-05 Benjamin Remy , Francois Lanusse , Niall Jeffrey , Jia Liu , Jean-Luc Starck , Ken Osato , Tim Schrabback

We consider the problem of subspace estimation in situations where the number of available snapshots and the observation dimension are comparable in magnitude. In this context, traditional subspace methods tend to fail because the…

Information Theory · Computer Science 2016-11-15 Pascal Vallet , Philippe Loubaton , Xavier Mestre

Imaging mass spectrometry (IMS) is a powerful tool for untargeted, highly multiplexed molecular mapping of tissue in biomedical research. IMS offers a means of mapping the spatial distributions of molecular species in biological tissue with…

Computer Vision and Pattern Recognition · Computer Science 2025-08-05 Yijie Zhang , Luzhe Huang , Nir Pillar , Yuzhu Li , Lukasz G. Migas , Raf Van de Plas , Jeffrey M. Spraggins , Aydogan Ozcan

Gaussian Boson sampling (GBS) provides a highly efficient approach to make use of squeezed states from parametric down-conversion to solve a classically hard-to-solve sampling problem. The GBS protocol not only significantly enhances the…

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