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Related papers: Correlation-based Beam Calibration of 21cm Intensi…

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Joint photocount distributions of a weak twin beam acquired by an iCCD camera are analyzed with respect to the beam spatial correlations. A method for extracting these correlations from the experimental joint photocount distributions is…

Quantum Physics · Physics 2018-12-11 Jan Perina , Vaclav Michalek , Ondrej Haderka

We implement a simple, main beam correction in the maximum-likelihood, parametric component separation approach, which allows on accounting for different beamwidths of input maps at different frequencies without any preprocessing. We…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-19 Arianna Rizzieri , Josquin Errard , Radek Stompor

The paper presents an alternative way to classical stereocorrelation. First, 2D image processing of random patterns is described. Sub-pixel displacements are determined using phase analysis. Then distortion evaluation is presented. The…

Classical Physics · Physics 2013-11-18 Jérôme Molimard , Gaetan Boyer , Hassan Zahouani

The study and application of signal detection techniques based on cross-correlation method for acoustic transient signals in noisy and reverberant environments are presented. These techniques are shown to provide high signal to noise ratio,…

Instrumentation and Detectors · Physics 2015-02-19 S. Adrián-Martínez , M. Ardid , M. Bou-Cabo , I. Felis , C. Llorens , J. A. Martínez-Mora , M. Saldaña

We consider modeling for strong-strong beam-beam interactions beyond preceding linearized/perturbative methods such as soft gaussian approximation or FMM (HFMM) etc. In our approach discrete coherent modes, discovered before, and possible…

Accelerator Physics · Physics 2007-05-23 Antonina N. Fedorova , Michael G. Zeitlin

Resolving sources beyond the diffraction limit is important in imaging, communications, and metrology. Current image-based methods of super-resolution require phase information (either of the source points or an added filter) and perfect…

Optics · Physics 2025-12-16 S. A. Wadood , Shaurya Aarav , Kevin Liang , Jason W Fleischer

A novel full-field surface profilometer using diffractive-based chromatic confocal microscopy and area-scan spectral sensing is developed. A normalized cross correlation algorithm was developed to establish a spectrum-depth response curve.…

Optics · Physics 2019-04-24 Duc Trung Nguyen , Liang-Chia Chen

Magnetic resonance imaging (MRI) plays a vital role in clinical diagnostics, yet it remains hindered by long acquisition times and motion artifacts. Multi-contrast MRI reconstruction has emerged as a promising direction by leveraging…

Computer Vision and Pattern Recognition · Computer Science 2026-01-15 Xinming Fang , Chaoyan Huang , Juncheng Li , Jun Wang , Jun Shi , Guixu Zhang

Calibration is a key step in the signal processing pipeline of any radio astronomical instrument. The required sky, ionospheric and instrumental models for this step can suffer from various kinds of incompleteness. In this paper we analyze…

Instrumentation and Methods for Astrophysics · Physics 2019-02-08 A. Mouri Sardarabadi , L. V. E. Koopmans

The inherent non-linearity of intensity correlation functions can be used to spatially distinguish identical emitters beyond the diffraction limit, as achieved, for example, in Super-Resolution Optical Fluctuation Imaging (SOFI). Here, we…

Optics · Physics 2024-12-18 Yifan Chen , Chieh Tsao , Hendrik Utzat

We propose a novel DNN based framework called the Enhanced Correlation Matching based Video Frame Interpolation Network to support high resolution like 4K, which has a large scale of motion and occlusion. Considering the extensibility of…

Computer Vision and Pattern Recognition · Computer Science 2021-11-18 Sungho Lee , Narae Choi , Woong Il Choi

Neutral hydrogen (HI) intensity mapping with single-dish experiments is a powerful approach for probing cosmology in the post-reionization epoch. However, the presence of bright foregrounds over four orders of magnitude stronger than the HI…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-03 Athanasia Gkogkou , Victor Bonjean , Jean-Luc Starck , Marta Spinelli , Panagiotis Tsakalides

In the fast developing countries it is hard to trace new buildings construction or old structures destruction and, as a result, to keep the up-to-date cadastre maps. Moreover, due to the complexity of urban regions or inconsistency of data…

Computer Vision and Pattern Recognition · Computer Science 2020-07-27 Stefano Zorzi , Ksenia Bittner , Friedrich Fraundorfer

The 21-cm global signal is obscured by very bright galactic and extra galactic foreground emissions. Typical single-spectrum fit (SSF) based methods for foreground/signal separation can result in biased estimates of the cosmological signal…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-27 Yordan D. Ignatov , Jonathan R. Pritchard

In the field of seismic interpretation, univariate databased maps are commonly used by interpreters, especially for fault detection. In these maps, contrast between target regions and the background is one of the main factors that affect…

Image and Video Processing · Electrical Eng. & Systems 2018-11-26 Zhen Wang , Dogancan Temel , Ghassan AlRegib

Radio interferometers consisting of identical antennas arranged on a regular lattice permit fast Fourier transform beamforming, which reduces the correlation cost from $\mathcal{O}(n^2)$ in the number of antennas to $\mathcal{O}(n\log n)$.…

Instrumentation and Methods for Astrophysics · Physics 2019-05-20 Kiyoshi W. Masui , J. Richard Shaw , Cherry Ng , Kendrick M. Smith , Keith Vanderlinde , Adiv Paradise

In a sky-averaged 21-cm signal experiment, the uncertainty on the extracted signal depends mainly on the covariance between the foreground and 21-cm signal models. In this paper, we construct these models using the modes of variation…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-19 Anchal Saxena , P. Daniel Meerburg , Eloy de Lera Acedo , Will Handley , Léon V. E. Koopmans

Radiation detectors deployed as part of a large urban network or for homeland security monitoring must maintain reliable energy calibration even when subjected to substantial variations in temperature and ambient background radiation.…

Instrumentation and Detectors · Physics 2026-04-23 Marco Salathe , Nicolas Abgrall , Mark S. Bandstra , Tenzing H. Y. Joshi , Brian J. Quiter , Reynold J. Cooper

Calibration precision is currently a limiting systematic in 21 cm cosmology experiments. While there are innumerable calibration approaches, most can be categorized as either `sky-based,' relying on an extremely accurate model of…

Instrumentation and Methods for Astrophysics · Physics 2021-03-17 Ruby Byrne , Miguel F. Morales , Bryna Hazelton , Michael Wilensky

Image enhancement aims at processing an input image so that the visual content of the output image is more pleasing or more useful for certain applications. Although histogram equalization is widely used in image enhancement due to its…

Computer Vision and Pattern Recognition · Computer Science 2021-01-18 Xiangyuan Zhu , Xiaoming Xiao , Tardi Tjahjadi , Zhihu Wu , Jin Tang
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