English
Related papers

Related papers: Imprecise k-space sampling and central brightening

200 papers

Intensity mapping has attracted significant interest as an approach to measure the properties of the interstellar medium in typical galaxies at high redshift. Intensity mapping measures the statistics of surface brightness as a function of…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-20 E. R. Switzer , C. J. Anderson , A. R. Pullen , S. Yang

Acquisition-to-acquisition signal intensity variations (non-standardness) are inherent in MR images. Standardization is a post processing method for correcting inter-subject intensity variations through transforming all images from the…

Computer Vision and Pattern Recognition · Computer Science 2015-05-18 Ulas Bagci , Jayaram K. Udupa , Li Bai

The principles of quantum optics have yielded a plethora of ideas to surpass the classical limitations of sensitivity and resolution in optical microscopy. While some ideas have been applied in proof-of-principle experiments, imaging a…

Low-frequency radio observations of neutral hydrogen during and before the epoch of cosmic reionization will provide ~ 1000 quasi-independent source planes, each of precisely known redshift, if a resolution of ~1 arcminutes or better can be…

Astrophysics · Physics 2017-03-15 R. Benton Metcalf , S. D. M. White

This paper is devoted to the problem of sampling Gaussian fields in high dimension. Solutions exist for two specific structures of inverse covariance : sparse and circulant. The proposed approach is valid in a more general case and…

Computation · Statistics 2011-05-31 F. Orieux , O. Féron , J. -F. Giovannelli

Image-based precision medicine aims to personalize treatment decisions based on an individual's unique imaging features so as to improve their clinical outcome. Machine learning frameworks that integrate uncertainty estimation as part of…

Machine Learning · Computer Science 2023-08-11 Joshua Durso-Finley , Jean-Pierre Falet , Raghav Mehta , Douglas L. Arnold , Nick Pawlowski , Tal Arbel

Gaussian boson sampling (GBS) is a model of nonuniversal quantum computation that claims to demonstrate quantum supremacy with current technologies. This model entails sampling photocounting events from a multimode Gaussian state at the…

Quantum Physics · Physics 2024-10-22 I. S. Yeremenko , M. A. Dmytruk , A. A. Semenov

We consider the scenario in which multiple sensors send spatially correlated data to a fusion center (FC) via independent Rayleigh-fading channels with additive noise. Assuming that the sensor data is sparse in some basis, we show that the…

Information Theory · Computer Science 2015-06-12 Gang Yang , Vincent Y. F. Tan , Chin Keong Ho , See Ho Ting , Yong Liang Guan

Knowledge of the primordial matter density field from which the large-scale structure of the Universe emerged over cosmic time is of fundamental importance for cosmology. However, reconstructing these cosmological initial conditions from…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-06 Oleg Savchenko , Guillermo Franco Abellán , Florian List , Noemi Anau Montel , Christoph Weniger

Measuring the volume weighted velocity power spectrum suffers from a severe systematic error, due to imperfect sampling of the velocity field from inhomogeneous distribution of dark matter particles/halos in simulations or galaxies with…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-10 Yi Zheng , Pengjie Zhang , Yipeng Jing

We examine the errors on counts in cells extracted from galaxy surveys. The measurement error, related to the finite number of sampling cells, is disentangled from the ``cosmic error'', due to the finiteness of the survey. Using the…

Astrophysics · Physics 2009-10-28 István Szapudi , Stéphane Colombi

Magnetic Resonance Imaging (MRI) has become an important technique in the clinic for the visualization, detection, and diagnosis of various diseases. However, one bottleneck limitation of MRI is the relatively slow data acquisition process.…

Image and Video Processing · Electrical Eng. & Systems 2022-11-28 Xue Liu , Juan Zou , Xiawu Zheng , Cheng Li , Hairong Zheng , Shanshan Wang

A new framework of compressive sensing (CS), namely statistical compressive sensing (SCS), that aims at efficiently sampling a collection of signals that follow a statistical distribution and achieving accurate reconstruction on average, is…

Computer Vision and Pattern Recognition · Computer Science 2010-10-22 Guoshen Yu , Guillermo Sapiro

Redshift-space clustering anisotropies caused by cosmic peculiar velocities provide a powerful probe to test the gravity theory on large scales. However, to extract unbiased physical constraints, the clustering pattern has to be modelled…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-28 Federico Marulli , Alfonso Veropalumbo , Lauro Moscardini , Andrea Cimatti , Klaus Dolag

Images taken by space telescopes typically have a superb spatial resolution, but a relatively poor sampling rate due to the finite CCD pixel size. Beyond the Nyquist limit, it becomes uncertain how much the pixelation effect may affect the…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-06 Zhi Shen , Jun Zhang , Hekun Li , Haoran Wang , Chengliang Wei , Guoliang Li , Xiaobo Li , Zhang Ban , Dan Yue

Fast coverage of k-space is a major concern to speed up data acquisition in Magnetic Resonance Imaging (MRI) and limit image distortions due to long echo train durations. The hardware gradient constraints (magnitude, slew rate) must be…

Optimization and Control · Mathematics 2014-12-31 Nicolas Chauffert , Pierre Weiss , Jonas Kahn , Philippe CIUCIU

We study the quantum Ising model in the transverse inhomogeneous magnetic field. Such a system can be approached numerically through exact diagonalization and analytically through the renormalization group techniques. Basic insights into…

Statistical Mechanics · Physics 2017-11-22 Mateusz Łącki , Bogdan Damski

In fMRI, capturing brain activation during a task is dependent on how quickly k-space arrays are obtained. Acquiring full k-space arrays, which are reconstructed into images using the inverse Fourier transform (IFT), that make up volume…

Applications · Statistics 2024-05-27 Chase J Sakitis , Daniel B Rowe

In array processing, a common problem is to estimate the angles of arrival of $K$ deterministic sources impinging on an array of $M$ antennas, from $N$ observations of the source signal, corrupted by gaussian noise. The problem reduces to…

Probability · Mathematics 2011-06-28 Walid Hachem , Philippe Loubaton , Xavier Mestre , Jamal Najim , Pascal Vallet

We present an X-ray absorption model for the interstellar medium, to be referred to as ISMabs, that takes into account both neutral and ionized species of cosmically abundant elements, and includes the most accurate atomic data available.…

High Energy Astrophysical Phenomena · Physics 2015-06-23 E. Gatuzz , J. García , T. R. Kallman , C. Mendoza , T. W. Gorczyca