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The problem of reconstructing an object from the measurements of the light it scatters is common in numerous imaging applications. While the most popular formulations of the problem are based on linearizing the object-light relationship,…

Computer Vision and Pattern Recognition · Computer Science 2017-12-15 Yanting Ma , Hassan Mansour , Dehong Liu , Petros T. Boufounos , Ulugbek S. Kamilov

We apply the stationary phase method developed in (Assier, Shanin \& Korolkov, QJMAM, 76(1), 2022) to the problem of wave diffraction by a quarter-plane. The wave field is written as a double Fourier transform of an unknown spectral…

Analysis of PDEs · Mathematics 2023-10-30 Raphael C. Assier , Andrey V. Shanin , Andrey I. Korolkov

We present an algorithm for the numeric calculation of antiferromagnetic resonance frequencies for the non-collinear antiferromagnets of general type. This algorithm uses general exchange symmetry approach \cite{andrmar} and is applicable…

Strongly Correlated Electrons · Physics 2017-01-11 V. Glazkov , T. Soldatov , Yu. Krasnikova

Recent developments in machine learning and signal processing have resulted in many new techniques that are able to effectively capture the intrinsic yet complex properties of hyperspectral imagery. Tasks ranging from anomaly detection to…

Computer Vision and Pattern Recognition · Computer Science 2020-11-24 Ilya Kavalerov , Weilin Li , Wojciech Czaja , Rama Chellappa

There are two alternative methods used in literature to calculate the incoherent part of the spectrum of light scattered by an atomic system. In the first, one calculates the spectrum of the total light scattered by the system and obtains…

Quantum Physics · Physics 2015-05-13 Z. Ficek

Diffusion models have become a leading paradigm for image super-resolution (SR), but existing methods struggle to guarantee both the high-frequency perceptual quality and the low-frequency structural fidelity of generated images. Although…

Computer Vision and Pattern Recognition · Computer Science 2026-04-14 Hexin Zhang , Dong Li , Jie Huang , Bingzhou Wang , Xueyang Fu , Zhengjun Zha

The study of third-order statistics in large-scale structure analyses has been hampered by the increased complexity of bispectrum estimators (compared to power spectra), the large dimensionality of the data vector, and the difficulty in…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-20 Lea Harscouet , Jessica A. Cowell , Julia Ereza , David Alonso , Hugo Camacho , Andrina Nicola , Anže Slosar

The performance of multivariate kernel density estimation (KDE) depends strongly on the choice of bandwidth matrix. The high computational cost required for its estimation provides a big motivation to develop fast and accurate methods. One…

Computation · Statistics 2016-05-13 Artur Gramacki , Jarosław Gramacki

We analyze the dispersion property of low-index thin lenses by using scalar diffraction and finite difference time domain (FDTD) methods. We compare the dispersion results obtained by using these methods with reported experimental results,…

Optics · Physics 2022-04-26 Ashfaqul Anwar Siraji , Yang Zhao

The Fast Aerosol Spectrometer (FASP) is a device for spectral aerosol measurements. Its purpose is to safely monitor the atmosphere inside a reactor containment. First we describe the FASP and explain its basic physical laws. Then we…

Numerical Analysis · Mathematics 2017-01-17 Tobias Kyrion , Graham Alldredge

Imaging devices exploit the Nyquist-Shannon sampling theorem to avoid both aliasing and redundant oversampling by design. Conversely, in medical image resampling, images are considered as continuous functions, are warped by a spatial…

Image and Video Processing · Electrical Eng. & Systems 2021-01-19 M. Jorge Cardoso , Marc Modat , Tom Vercauteren , Sebastien Ourselin

This article addresses the problem of two- and higher dimensional pattern matching, i.e. the identification of instances of a template within a larger signal space, which is a form of registration. Unlike traditional correlation, we aim at…

Distributed, Parallel, and Cluster Computing · Computer Science 2007-09-19 Luciano da Fontoura Costa , Erik Bollt

In this paper, we propose Fourier pseudospectral methods to solve the variable-order space fractional wave equation and develop an accelerated matrix-free approach for its effective implementation. In constant-order cases, our methods can…

Numerical Analysis · Mathematics 2024-02-06 Yanzhi Zhang , Xiaofei Zhao , Shiping Zhou

Cross-domain few-shot learning (CD-FSL) requires models to generalize from limited labeled samples under significant distribution shifts. While recent methods enhance adaptability through lightweight task-specific modules, they operate…

Computer Vision and Pattern Recognition · Computer Science 2025-05-14 Ruixiao Shi , Fu Feng , Yucheng Xie , Jing Wang , Xin Geng

The usual fluid equations describing the large-scale evolution of mass density in the universe can be written as local in the density, velocity divergence, and velocity potential fields. As a result, the perturbative expansion in small…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-01 Marcel Schmittfull , Zvonimir Vlah , Patrick McDonald

This paper presents a method to interpolate a periodic band-limited signal from its samples lying at nonuniform positions in a regular grid, which is based on the FFT and has the same complexity order as this last algorithm. This kind of…

Information Theory · Computer Science 2016-11-17 J. Selva

The frequency-domain approach (FDA) to transient analysis of the boundary element method, although is appealing for engineering applications, is computationally expensive. This paper proposes a novel adaptive frequency sampling (AFS)…

Numerical Analysis · Mathematics 2016-02-09 Jinyou Xiao , Junjie Rong , Wenjing Ye , Chuanzeng Zhang

Quarter sampling is a novel sensor design that allows for an acquisition of higher resolution images without increasing the number of pixels. When being used for video data, one out of four pixels is measured in each frame. Effectively,…

Image and Video Processing · Electrical Eng. & Systems 2022-03-18 Simon Grosche , Jürgen Seiler , André Kaup

Modeling the large-scale structure of the universe on nonlinear scales has the potential to substantially increase the science return of upcoming surveys by increasing the number of modes available for model comparisons. One way to achieve…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-30 Marcel Schmittfull , Zvonimir Vlah

We present a simple 'shift-and-add' based improvement in the angular resolution of single electron backscatter diffraction (EBSD) patterns. Sub-pixel image registration is used to measure the (sub-pixel) difference in projection parameters…

Instrumentation and Detectors · Physics 2025-12-15 Ben Britton , Tianbi Zhang