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Wavelet based algorithms in numerical analysis are similar to other transform methods in that vectors and operators are expanded into a basis and the computations take place in this new system of coordinates. However, due to the recursive…

comp-gas · Physics 2008-02-03 G. Beylkin

This paper presents a new method for the reconstruction of weak lensing mass maps. It uses the multiscale entropy concept, which is based on wavelets, and the False Discovery Rate which allows us to derive robust detection levels in wavelet…

Astrophysics · Physics 2009-11-10 Jean-Luc Starck , Sandrine Pires , Alexandre Refregier

Faraday tomography is a novel method to probe 3-dimensional structure of magnetic fields of polarized radio sources. In this paper, we investigate Faraday dispersion function (FDF) of disk galaxies extending a simple analytic model of…

Astrophysics of Galaxies · Physics 2020-09-16 Haruya Eguchi , Masaki Suzuki , Yoshimitsu Miyashita , Shinsuke Ideguchi , Keitaro Takahashi

Highly-directional image artifacts such as ion mill curtaining, mechanical scratches, or image striping from beam instability degrade the interpretability of micrographs. These unwanted, aperiodic features extend the image along a primary…

Computer Vision and Pattern Recognition · Computer Science 2019-06-26 Jonathan Schwartz , Yi Jiang , Yongjie Wang , Anthony Aiello , Pallab Bhattacharya , Hui Yuan , Zetian Mi , Nabil Bassim , Robert Hovden

We present a broadband spectropolarimetric survey of 563 discrete, mostly unresolved radio sources between 1.3 \& 2.0 GHz using data taken with the Australia Telescope Compact Array (ATCA). We have used rotation measure synthesis to…

Astrophysics of Galaxies · Physics 2015-12-16 C. S. Anderson , B. M. Gaensler , I. J. Feain , T. M. O. Franzen

Controlling the False Discovery Rate (FDR) in a variable selection procedure is critical for reproducible discoveries, and it has been extensively studied in sparse linear models. However, it remains largely open in scenarios where the…

Methodology · Statistics 2023-11-16 Yang Cao , Xinwei Sun , Yuan Yao

The detection of fast radio bursts (FRBs) in radio astronomy is a complex task due to the challenges posed by radio frequency interference (RFI) and signal dispersion in the interstellar medium. Traditional search algorithms are often…

Instrumentation and Methods for Astrophysics · Physics 2024-10-07 Yong-Kun Zhang , Di Li , Yi Feng , Chao-Wei Tsai , Pei Wang , Chen-Hui Niu , Hua-Xi Chen , Yu-Hao Zhu

Spatial resolution of most imaging devices is fundamentally restricted by diffraction. This limitation is manifested in the loss of high spatial frequency information contained in evanescent waves. As a result, conventional far-field optics…

Optics · Physics 2010-03-16 Leonid Alekseyev , Evgenii Narimanov , Jacob Khurgin

We investigate the capability of ongoing radio telescopes for probing Faraday rotation measure (RM) due to the intergalactic magnetic field (IGMF) in the large-scale structure of the universe which is expected to be of order $O(1) {\rm…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Shinsuke Ideguchi , Keitaro Takahashi , Takuya Akahori , Kohei Kumazaki , Dongsu Ryu

Full-Waveform Inversion (FWI) has now become a widely accepted tool to obtain high-resolution velocity models from seismic data. Typically, the velocity model in its discrete form is represented on a rectangular grid, and we solve for the…

Geophysics · Physics 2022-01-25 Reetam Biswas , Mrinal K. Sen

Pre-trained vision foundation models (VFMs) provide strong semantic representations, yet their patch-level features are inherently coarse, limiting their effectiveness on tasks requiring fine-grained localization, dense prediction, and…

Computer Vision and Pattern Recognition · Computer Science 2026-05-21 Wentong Li , Zhiyuan Qi , Zichen Zhao , Kai Zhang , Lei Zhang

Image restoration aims to recover high-quality images from degraded observations. When the degradation process is known, the recovery problem can be formulated as an inverse problem, and in a Bayesian context, the goal is to sample a clean…

Image and Video Processing · Electrical Eng. & Systems 2025-10-13 Darshan Thaker , Abhishek Goyal , René Vidal

Optical flow estimation aims to find the 2D motion field by identifying corresponding pixels between two images. Despite the tremendous progress of deep learning-based optical flow methods, it remains a challenge to accurately estimate…

Computer Vision and Pattern Recognition · Computer Science 2022-04-01 Xiuchao Sui , Shaohua Li , Xue Geng , Yan Wu , Xinxing Xu , Yong Liu , Rick Goh , Hongyuan Zhu

Frequency-domain full-waveform inversion (FWI) is suitable for long-offset stationary-recording acquisition, since reliable subsurface models can be reconstructed with a few frequencies and attenuation is easily implemented without…

Computational Physics · Physics 2020-04-15 Victorita Dolean , Pierre Jolivet , Stéphane Operto , Pierre-Henri Tournier

Faraday tomography is a powerful method to diagnose polarizations and Faraday rotations along the line of sight. The quality of Faraday tomography is, however, limited by several conditions. Recently, it is reported that Faraday tomography…

Instrumentation and Methods for Astrophysics · Physics 2014-05-26 Kohei Kumazaki , Takuya Akahori , Shinsuke Ideguchi , Tomoharu Kurayama , Keitaro Takahashi

Ellipsometry techniques allow to measure polarization information of materials, requiring precise rotations of optical components with different configurations of lights and sensors. This results in cumbersome capture devices, carefully…

Graphics · Computer Science 2023-02-09 Inseung Hwang , Daniel S. Jeon , Adolfo Muñoz , Diego Gutierrez , Xin Tong , Min H. Kim

Diffuse scattering is a rich source of information about disorder in crystalline materials, which can be modelled using atomistic techniques such as Monte Carlo and molecular dynamics simulations. Modern X-ray and neutron scattering…

Materials Science · Physics 2018-12-21 Joseph A. M. Paddison

The Fast Fourier Transform(FFT) is a classic signal processing algorithm that is utilized in a wide range of applications. For image processing, FFT computes on every pixel's value of an image, regardless of their properties in frequency…

Signal Processing · Electrical Eng. & Systems 2020-02-25 Sheng Shi , Runkai Yang , Haihang You

Variations in the Faraday rotation measure (RM) of repeating fast radio bursts (FRBs) provide critical diagnostics of the dynamically evolving magneto-ionic environments surrounding their progenitors. Sudden, transient ``RM flares'' can…

High Energy Astrophysical Phenomena · Physics 2026-05-28 Yuan-Pei Yang , Boyang Liu

Diffraction tomography aims to recover an object's scattering potential from measured wave fields. In the classical setting, the object is illuminated by plane waves from many directions, and the Fourier diffraction theorem provides a…

Numerical Analysis · Mathematics 2026-03-11 Peter Elbau , Noemi Naujoks
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