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A unified approach to derive optimal finite differences is presented which combines three critical elements for numerical performance especially for multi-scale physical problems, namely, order of accuracy, spectral resolution and…

Computational Physics · Physics 2019-10-23 Komal Kumari , Raktim Bhattacharya , Diego A. Donzis

The size and compute characteristics of modern large language models have led to an increased interest in developing specialized kernels tailored for particular training and inference workloads. Existing kernels primarily optimize for…

Machine Learning · Computer Science 2025-12-05 Aniruddha Nrusimha , William Brandon , Mayank Mishra , Yikang Shen , Rameswar Panda , Jonathan Ragan-Kelley , Yoon Kim

Recursive, causal and non-causal, multidimensional digital filters, with infinite impulse responses and maximally flat magnitude and delay responses in the low-frequency region, are designed to negate correlated clutter and interference in…

Computer Vision and Pattern Recognition · Computer Science 2015-04-02 Hugh L. Kennedy

Variational regularization techniques are dominant in the field of mathematical imaging. A drawback of these techniques is that they are dependent on a number of parameters which have to be set by the user. A by now common strategy to…

Optimization and Control · Mathematics 2020-12-10 Matthias J. Ehrhardt , Lindon Roberts

A new sampling method for inverse scattering problems is proposed to process far field data of one incident wave. As the linear sampling method, the method sets up ill-posed integral equations and uses the (approximate) solutions to…

Analysis of PDEs · Mathematics 2018-08-01 Juan Liu , Jiguang Sun

Selecting an appropriate prior to compensate for information loss due to the measurement operator is a fundamental challenge in imaging inverse problems. Implicit priors based on denoising neural networks have become central to widely-used…

Image and Video Processing · Electrical Eng. & Systems 2025-06-10 Matthieu Terris , Ulugbek S. Kamilov , Thomas Moreau

A major performance and complexity limitation in broadband communications is the long channel delay spread which results in a highly-frequency-selective channel frequency response. Channel shortening equalizers (CSEs) are used to ensure…

Information Theory · Computer Science 2018-03-06 Abubakr O. Al-Abbasi , Ridha Hamila , Waheed U. Bajwa , Naofal Al-Dhahir

The design of digital filters is a fundamental process in the context of digital signal processing. The purpose of this paper is to study the use of $\lp$ norms (for $2 < p < \infty$) as design criteria for digital filters, and to introduce…

Information Theory · Computer Science 2012-07-20 Ricardo A. Vargas , C. Sidney Burrus

We develop sparse array receive beamformer design methods achieving maximum signal-to-interference plus noise ratio (MaxSINR) for wideband sources and jammers. Both tapped delay line (TDL) filtering and the DFT realizations to wideband…

Signal Processing · Electrical Eng. & Systems 2020-11-16 Syed A. Hamza , Moeness Amin

Inverse scattering problems, such as those in electromagnetic imaging using phaseless data (PD-ISPs), involve imaging objects using phaseless measurements of wave scattering. Such inverse problems can be highly non-linear and ill-posed…

Signal Processing · Electrical Eng. & Systems 2022-12-07 Samruddhi Deshmukh , Amartansh Dubey , Ross Murch

Estimating camera geometry typically involves solving minimal problems formulated as systems of multivariate polynomial equations, which often pose computational challenges when using existing Gr\"obner-basis or resultant-based methods due…

Computer Vision and Pattern Recognition · Computer Science 2026-05-08 Haidong Wu , Snehal Bhayani , Janne Heikkilä

This paper presents a new finite difference algorithm for solving the 2D one-way wave equation with a preliminary approximation of a pseudo-differential operator by a system of partial differential equations. As opposed to the existing…

Numerical Analysis · Mathematics 2017-03-02 Andrew V. Terekhov

We present several versions of Regularized Combined Field Integral Equation (CFIER) formulations for the solution of three dimensional frequency domain electromagnetic scattering problems with Perfectly Electric Conducting (PEC) boundary…

Numerical Analysis · Mathematics 2014-04-08 Yassine Boubendir , Catalin Turc

While diffusion-based generative models have made significant strides in visual content creation, conventional approaches face computational challenges, especially for high-resolution images, as they denoise the entire image from noisy…

Computer Vision and Pattern Recognition · Computer Science 2025-07-01 Haohang Xu , Longyu Chen , Yichen Zhang , Shuangrui Ding , Zhipeng Zhang

We use high order finite difference methods to solve the wave equation in the second order form. The spatial discretization is performed by finite difference operators satisfying a summation-by-parts property. The focus of this work is on…

Numerical Analysis · Mathematics 2017-02-08 Siyang Wang , Kristoffer Virta , Gunilla Kreiss

This article presents a novel perspective along with a scalable methodology to design a fault detection and isolation (FDI) filter for high dimensional nonlinear systems. Previous approaches on FDI problems are either confined to linear…

Optimization and Control · Mathematics 2016-01-25 Peyman Mohajerin Esfahani , John Lygeros

This paper revisits the design and optimization of parallel fast finite impulse response (FIR) filters using polyphase decomposition and iterated fast FIR algorithms (FFAs). Parallel FIR filtering enhances computational efficiency and…

Signal Processing · Electrical Eng. & Systems 2026-01-23 Keshab K. Parhi

Model-Based Iterative Reconstruction (MBIR) is important because direct methods, such as Filtered Back-Projection (FBP) can introduce significant noise and artifacts in sparse-angle tomography, especially for time-evolving samples. Although…

Mathematical Software · Computer Science 2026-03-31 Dinesh Kumar , Jeffrey Donatelli

We present a novel approach that integrates unfitted finite element methods and neural networks to approximate partial differential equations on complex geometries. Easy-to-generate background meshes (e.g., a simple Cartesian mesh) that cut…

Numerical Analysis · Mathematics 2025-12-04 Wei Li , Alberto F. Martín , Santiago Badia

In this work, a simple and efficient dual iterative refinement (DIR) method is proposed for dense correspondence between two nearly isometric shapes. The key idea is to use dual information, such as spatial and spectral, or local and global…

Computer Vision and Pattern Recognition · Computer Science 2020-11-20 Rui Xiang , Rongjie Lai , Hongkai Zhao