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We implement an all-optical setup demonstrating kernel-based quantum machine learning for two-dimensional classification problems. In this hybrid approach, kernel evaluations are outsourced to projective measurements on suitably designed…

In this paper we present a high-order kernel method for numerically solving diffusion and reaction-diffusion partial differential equations (PDEs) on smooth, closed surfaces embedded in $\mathbb{R}^d$. For two-dimensional surfaces embedded…

Numerical Analysis · Mathematics 2012-06-04 Edward J. Fuselier , Grady B. Wright

We developed a fast numerical algorithm for solving the three dimensional vectorial Helmholtz equation that arises in electromagnetic scattering problems. The algorithm is based on electric field integral equations and is essentially a…

Computational Physics · Physics 2019-07-24 S. B. Wang , H. H. Zheng , J. J. Xiao , Z. F. Lin , C. T. Chan

In this paper, we present a multiscale framework for solving the Helmholtz equation in heterogeneous media without scale separation and in the high frequency regime where the wavenumber $k$ can be large. The main innovation is that our…

Numerical Analysis · Mathematics 2022-10-21 Yifan Chen , Thomas Y. Hou , Yixuan Wang

We present a unified treatment of the Fourier spectra of spherically symmetric nonlocal diffusion operators. We develop numerical and analytical results for the class of kernels with weak algebraic singularity as the distance between source…

Numerical Analysis · Mathematics 2019-09-04 Yu Li , Richard Mikael Slevinsky

We propose a deep learning framework based on an encoder-decoder architecture for the design and evaluation of cloaking devices, demonstrated in this work for two-dimensional wave propagation governed by the Helmholtz equation. The cloaks…

Computational Physics · Physics 2026-05-22 Camille Carvalho , Elsie Cortes , Chrysoula Tsogka , Symeon Papadimitropoulos

We consider the 2D quasi-periodic scattering problem in optics, which has been modelled by a boundary value problem governed by Helmholtz equation with transparent boundary conditions. A spectral collocation method and a tensor product…

Numerical Analysis · Mathematics 2015-07-14 Kui Du

This paper analyzes inverse scattering for the one-dimensional Helmholtz equation in the case where the wave speed is piecewise constant. Scattering data recorded for an arbitrarily small interval of frequencies is shown to determine the…

Analysis of PDEs · Mathematics 2020-08-26 Sophia Bugarija , Peter C. Gibson , Guanghui Hu , Peijun Li , Yue Zhao

The bilateral and nonlocal means filters are instances of kernel-based filters that are popularly used in image processing. It was recently shown that fast and accurate bilateral filtering of grayscale images can be performed using a…

Computer Vision and Pattern Recognition · Computer Science 2019-02-20 Pravin Nair , Kunal N. Chaudhury

We consider the inverse scattering problem for inhomogeneous media of compact support governed by the fractional s-Helmholtz equation, with $0<s<1$, in dimensions $d=1,2,3$. In particular, we study the determination of the support of the…

Analysis of PDEs · Mathematics 2026-04-30 Dana Zilberberg

We consider the numerical solution of high-frequency scattering problems modeled by the Helmholtz equation with a bounded obstacle. Although the analysis of this problem dates back at least 50 years, over the past decade or so, tools and…

Numerical Analysis · Mathematics 2026-03-24 Jeffrey Galkowski , Euan A. Spence

In this work, we study the accuracy and efficiency of hierarchical matrix ($\mathcal{H}$-matrix) based fast methods for solving dense linear systems arising from the discretization of the 3D elastodynamic Green's tensors. It is well known…

Numerical Analysis · Mathematics 2017-10-25 Stéphanie Chaillat , Luca Desiderio , Patrick Ciarlet

We introduce a fast algorithm for computing sparse Fourier transforms supported on smooth curves or surfaces. This problem appear naturally in several important problems in wave scattering and reflection seismology. The main observation is…

Numerical Analysis · Mathematics 2008-01-11 Lexing Ying

In the present paper we describe a simple black box algorithm for efficiently and accurately solving scattering problems related to the scattering of time-harmonic waves from radially-symmetric potentials in two dimensions. The method uses…

Numerical Analysis · Mathematics 2020-08-03 Jeremy Hoskins , Vladimir Rokhlin

A discretization scheme for variable coefficient Helmholtz problems on two-dimensional domains is presented. The scheme is based on high-order spectral approximations and is designed for problems with smooth solutions. The resulting system…

Numerical Analysis · Mathematics 2012-06-20 P. G. Martinsson

In this paper, we propose the idea of radial scaling in frequency domain and activation functions with compact support to produce a multi-scale DNN (MscaleDNN), which will have the multi-scale capability in approximating high frequency and…

Machine Learning · Computer Science 2019-10-28 Wei Cai , Zhi-Qin John Xu

Learning high-dimensional distributions is an important yet challenging problem in machine learning with applications in various domains. In this paper, we introduce new techniques to formulate the problem as solving Fokker-Planck equation…

Machine Learning · Computer Science 2021-05-11 Yufan Zhou , Changyou Chen , Jinhui Xu

A butterfly-based fast direct integral equation solver for analyzing high-frequency scattering from two-dimensional objects is presented. The solver leverages a randomized butterfly scheme to compress blocks corresponding to near- and…

Numerical Analysis · Mathematics 2017-06-07 Yang Liu , Han Guo , Eric Michielssen

We present a near linear time algorithm for constructing hierarchical nets in finite metric spaces with constant doubling dimension. This data-structure is then applied to obtain improved algorithms for the following problems: Approximate…

Data Structures and Algorithms · Computer Science 2007-05-23 Sariel Har-Peled , Manor Mendel

Hyperspectral imagery is rich in spatial and spectral information. Using 3D-CNN can simultaneously acquire features of spatial and spectral dimensions to facilitate classification of features, but hyperspectral image information spectral…

Image and Video Processing · Electrical Eng. & Systems 2022-02-15 Guandong Li , Chunju Zhang