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Related papers: SpecSolve: Spectral methods for spectral measures

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Speckle noise is generated along with the SAR imaging mechanism and degrades the quality of SAR images, leading to difficult interpretation. Hence, despeckling is an indispensable step in SAR pre-processing. Fortunately, supervised learning…

Image and Video Processing · Electrical Eng. & Systems 2025-03-26 Liang Chen , Yifei Yin , Hao Shi , Jingfei He , Wei Li

Spectral-spatial processing has been increasingly explored in remote sensing hyperspectral image classification. While extensive studies have focused on developing methods to improve the classification accuracy, experimental setting and…

Computer Vision and Pattern Recognition · Computer Science 2017-03-08 Jie Liang , Jun Zhou , Yuntao Qian , Lian Wen , Xiao Bai , Yongsheng Gao

The goal of the present work is to solve a linear dispersive equation with variable coefficient advection on an unbounded domain. In this setting, transparent boundary conditions are vital to allow waves to leave (or even re-enter) the,…

Numerical Analysis · Mathematics 2021-06-09 Lukas Einkemmer , Alexander Ostermann , Mirko Residori

We propose a spectral collocation method to approximate the exact boundary control of the wave equation in a square domain. The idea is to introduce a suitable approximate control problem that we solve in the finite-dimensional space of…

Numerical Analysis · Mathematics 2023-04-17 Somia Boumimez , Carlos Castro

Spectroscopy is a central pillar of materials characterization, providing useful information on properties like structure, composition, or excited state dynamics of a system. However, many spectroscopic techniques present challenges in…

Materials Science · Physics 2026-04-09 Amalya C. Johnson , Chris Fajardo , Leena Sansguiri , Weike Ye , Steven B. Torrisi

The normal mode model is one of the most popular approaches for solving underwater sound propagation problems. Among other methods, the finite difference method is widely used in classic normal mode programs. In many recent studies, the…

Computational Physics · Physics 2020-10-14 Houwang Tu , Yongxian Wang , Qiang Lan , Wei Liu , Wenbin Xiao , Shuqing Ma

We consider nonlinear eigenvalue problems to compute all eigenvalues in a bounded region on the complex plane. Based on domain decomposition and contour integrals, two robust and scalable parallel multi-step methods are proposed. The first…

Numerical Analysis · Mathematics 2024-01-18 Yingxia Xi , Jiguang Sun

SPSMAT (Spectral/Pseudospectral matrix method) is an add-on for Octave, that helps you solve nonfractional-/fractional ordinary/partial differential/integral equations. In this version, as the first version, the well-defined spectral or…

Mathematical Software · Computer Science 2019-06-25 Sobhan Latifi , Mehdi Delkhosh

This paper concerns a spectral estimation problem in which we want to find a spectral density function that is consistent with estimated second-order statistics. It is an inverse problem admitting multiple solutions, and selection of a…

Optimization and Control · Mathematics 2019-08-08 Bin Zhu

Hyperspectral imaging is useful for applications ranging from medical diagnostics to agricultural crop monitoring; however, traditional scanning hyperspectral imagers are prohibitively slow and expensive for widespread adoption. Snapshot…

Image and Video Processing · Electrical Eng. & Systems 2020-09-30 Kristina Monakhova , Kyrollos Yanny , Neerja Aggarwal , Laura Waller

Permutation synchronization is an important problem in computer science that constitutes the key step of many computer vision tasks. The goal is to recover $n$ latent permutations from their noisy and incomplete pairwise measurements. In…

Statistics Theory · Mathematics 2024-05-13 Duc Nguyen , Anderson Ye Zhang

Starting from the observation that one of the most successful methods for solving the Kohn-Sham equations for periodic systems -- the plane-wave method -- is a spectral method based on eigenfunction expansion, we formulate a spectral method…

Computational Physics · Physics 2016-03-08 Amartya S. Banerjee , Ryan S. Elliott , Richard D. James

Spectropolarimetry, the observation of polarization and intensity as a function of wavelength, is a powerful tool in stellar astrophysics. It is particularly useful for characterizing stars and circumstellar material, and for tracing the…

In this article, we introduce a general theoretical framework to analyze non-consistent approximations of the discrete eigenmodes of a self-adjoint operator. We focus in particular on the discrete eigenvalues laying in spectral gaps. We…

Functional Analysis · Mathematics 2012-05-03 Eric Cancès , Virginie Ehrlacher , Yvon Maday

We present a spectral method for parabolic partial differential equations with zero Dirichlet boundary conditions. The region {\Omega} for the problem is assumed to be simply-connected and bounded, and its boundary is assumed to be a smooth…

Numerical Analysis · Mathematics 2012-04-02 Kendall Atkinson , Olaf Hansen , David Chien

We show the effectiveness of automatic differentiation in efficiently and correctly computing and controlling the spectrum of implicitly linear operators, a rich family of layer types including all standard convolutional and dense layers.…

Machine Learning · Computer Science 2024-10-08 Ali Ebrahimpour Boroojeny , Matus Telgarsky , Hari Sundaram

Spectral measurements in the infrared (IR) optical range provide unique fingerprints of materials which are useful for material analysis, environmental sensing, and health diagnostics. Current IR spectroscopy techniques require the use of…

Quantum Physics · Physics 2016-02-05 Dmitry A. Kalashnikov , Anna V. Paterova , Sergei P. Kulik , Leonid A. Krivitsky

Orbital solutions for binary or multiple stellar systems that combine astrometry (e.g., position angles and angular separations) with spectroscopy (radial velocities) have important advantages over astrometric-only or spectroscopic-only…

Astrophysics · Physics 2007-05-23 Guillermo Torres

Nonlinear spectral problems arise across a range of fields, including mechanical vibrations, fluid-solid interactions, and photonic crystals. Discretizing infinite-dimensional nonlinear spectral problems often introduces significant…

Numerical Analysis · Mathematics 2025-04-25 Matthew J. Colbrook , Catherine Drysdale

We give exact formulae for a wide family of complexity measures that capture the organization of hidden nonlinear processes. The spectral decomposition of operator-valued functions leads to closed-form expressions involving the full…

Statistical Mechanics · Physics 2013-09-17 James P. Crutchfield , Christopher J. Ellison , Paul M. Riechers