English
Related papers

Related papers: Nonuniform fast Fourier transforms with nonequispa…

200 papers

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

The standing waves existed in radio telescope data are primarily due to reflections among the instruments, which significantly impact the spectrum quality of the Five-hundred-meter Aperture Spherical radio Telescope (FAST). Eliminating…

Instrumentation and Methods for Astrophysics · Physics 2025-01-09 Chen Xu , Jie Wang , Yingjie Jing , Fujia Li , Hengqian Gan , Ziming Liu , Tiantian Liang , Qingze Chen , Zerui Liu , Zhipeng Hou , Hao Hu , Huijie Hu , Shijie Huang , Peng Jiang , Chuan-Peng Zhang , Yan Zhu

Gaussian processes are widely used for the analysis of spatial data due to their nonparametric flexibility and ability to quantify uncertainty, and recently developed scalable approximations have facilitated application to massive datasets.…

Methodology · Statistics 2021-10-13 F. William Townes , Barbara E. Engelhardt

In this paper we consider Sparse Fourier Transform (SFT) algorithms for approximately computing the best $s$-term approximation of the Discrete Fourier Transform (DFT) $\mathbf{\hat{f}} \in \mathbb{C}^N$ of any given input vector…

Numerical Analysis · Mathematics 2017-06-12 Sami Merhi , Ruochuan Zhang , Mark A. Iwen , Andrew Christlieb

Nonnegative matrix factorization (NMF) is a popular method for audio spectral unmixing. While NMF is traditionally applied to off-the-shelf time-frequency representations based on the short-time Fourier or Cosine transforms, the ability to…

Machine Learning · Statistics 2018-11-07 Pierre Ablin , Dylan Fagot , Herwig Wendt , Alexandre Gramfort , Cédric Févotte

To reach the next frontier in multimode nonlinear optics, it is crucial to better understand the classical and quantum phenomena of systems with many interacting degrees of freedom -- both how they emerge and how they can be tailored to…

Machine learning applied to computer vision and signal processing is achieving results comparable to the human brain on specific tasks due to the great improvements brought by the deep neural networks (DNN). The majority of state-of-the-art…

Computer Vision and Pattern Recognition · Computer Science 2020-06-30 José Augusto Stuchi , Levy Boccato , Romis Attux

Recent progress in synthetic aperture sonar (SAS) technology and processing has led to significant advances in underwater imaging, outperforming previously common approaches in both accuracy and efficiency. There are, however, inherent…

Numerical Analysis · Mathematics 2017-06-28 John McKay , Anne Gelb , Vishal Monga , Raghu Raj

Using the existence of infinite numbers $k$ in the non-Archimedean ring of Robinson-Colombeau, we define the hyperfinite Fourier transform (HFT) by considering integration extended to $[-k,k]^{n}$ instead of $(-\infty,\infty)^{n}$. In order…

Functional Analysis · Mathematics 2022-10-03 Akbarali Mukhammadiev , Diksha Tiwari , Paolo Giordano

The standard particle-in-cell algorithm suffers from grid heating. There exists a gridless alternative which bypasses the deposition step and calculates each Fourier mode of the charge density directly from the particle positions. We show…

Plasma Physics · Physics 2019-09-04 Matthew S. Mitchell , Matthew T. Miecnikowski , Gregory Beylkin , Scott E. Parker

The quadratic phase Fourier transform QPFT is a neoteric addition to the class of Fourier transforms and embodies a variety of signal processing tools including the Fourier, fractional Fourier, linear canonical, and special affine Fourier…

Functional Analysis · Mathematics 2022-07-21 Aamir H. Dar , M. Younus Bhat

Non-negative Matrix Factorization (NMF) is one of the most popular techniques for data representation and clustering, and has been widely used in machine learning and data analysis. NMF concentrates the features of each sample into a…

Image and Video Processing · Electrical Eng. & Systems 2021-03-26 Mulin Chen , Maoguo Gong , Xuelong Li

We introduce the directional short-time fractional Fourier transform (DSTFRFT) and prove an extended Parseval's identity and a reconstruction formula for it. We also investigate the continuity of both the directional short-time fractional…

Functional Analysis · Mathematics 2025-09-17 Astrit Ferizi , Katerina Hadzi-Velkova Saneva , Snjezana Maksimovic

The fractional Fourier transform (FRFT) naturally exists in the strongly nonlocal nonlinear (SNN) media and the propagation of optical beams in SNN media can be simply regarded as a self-induced FRFT. Through FRFT technic the evolution of…

Optics · Physics 2008-12-17 Daquan Lu , Wei Hu , Yajian zheng , Yanbin liang , Longgui Cao , Sheng Lan , Qi Guo

The special unitary group SU(2) plays a fundamental role in the description of symmetries in quantum mechanics, theoretical physics, and spherical signal processing. In this paper, we address the computational challenges of performing…

Computational Physics · Physics 2026-05-26 Julio Delgado , Alejandro Umaña

The Discrete Fourier Transform (DFT) is essential for various applications ranging from signal processing to convolution and polynomial multiplication. The groundbreaking Fast Fourier Transform (FFT) algorithm reduces DFT time complexity…

Hardware Architecture · Computer Science 2023-04-06 Orian Leitersdorf , Yahav Boneh , Gonen Gazit , Ronny Ronen , Shahar Kvatinsky

The quantum Fourier transform for discrete variable (dvQFT) is an efficient algorithm for several applications. It is usually considered for the processing of quantum bits (qubits) and its efficient implementation is obtained with two…

Quantum Physics · Physics 2025-12-16 Gianfranco Cariolaro , Edi Ruffa , Amir Mohammad Yaghoobianzadeh , Jawad A. Salehi

Many experiments, and in particular gravitational wave detectors, produce continuous streams of data whose frequency representations contain discrete, relatively narrowband coherent features at high amplitude. We discuss the application of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 E. J. Daw , M. R. Hewitson

Pseudo-spectral method is one of the most accurate techniques for simulating turbulent flows. Fast Fourier transform (FFT) is an integral part of this method. In this paper, we present a new procedure to compute FFT in which we save…

Mathematical Software · Computer Science 2014-06-24 A. G. Chatterjee , M. K. Verma , M. Chaudhuri

Distributed microphone arrays composed of multiple subarrays enable blind source separation over a wide spatial area. Directly applying fast multichannel nonnegative matrix factorization (FastMNMF) to all subarrays can exploit observations…

Audio and Speech Processing · Electrical Eng. & Systems 2026-05-20 Hirotaka Nishikori , Nobutaka Ito , Kouei Yamaoka , Norihiro Takamune , Hiroshi Saruwatari
‹ Prev 1 8 9 10 Next ›