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Gravitational wave detectors produce time series of the gravitational wave strain co-added with instrument noise. For evenly sampled data, such as from laser interferometers, it has been traditional to Fourier transform the data and perform…

General Relativity and Quantum Cosmology · Physics 2025-11-14 Neil J. Cornish

Domain generalization aims to learn a generalizable model from a known source domain for various unknown target domains. It has been studied widely by domain randomization that transfers source images to different styles in spatial space…

Computer Vision and Pattern Recognition · Computer Science 2021-03-04 Jiaxing Huang , Dayan Guan , Aoran Xiao , Shijian Lu

Sampling strategies are important for sparse imaging methodologies, especially those employing the discrete Fourier transform (DFT). Chaotic sensing is one such methodology that employs deterministic, fractal sampling in conjunction with…

Image and Video Processing · Electrical Eng. & Systems 2022-05-23 Jacob M. White , Stuart Crozier , Shekhar S. Chandra

In spatio-temporal analysis, we often record data at specific time intervals but with varying spatial locations between these timepoints. We propose a conditional model to analyze such spatio-temporal data that accommodates the dependencies…

Methodology · Statistics 2026-04-03 Subhrajyoty Roy , Soudeep Deb , Sayar Karmakar , Rishideep Roy

Motivated by a host of recent applications requiring some amount of redundancy, frames are becoming a standard tool in the signal processing toolbox. In this paper, we study a specific class of frames, known as discrete Fourier transform…

Information Theory · Computer Science 2012-05-23 Mojtaba Vaezi , Fabrice Labeau

Nonstationary time series forecasting suffers from the distribution shift issue due to the different distributions that produce the training and test data. Existing methods attempt to alleviate the dependence by, e.g., removing low-order…

Machine Learning · Computer Science 2026-02-20 Xihao Piao , Zheng Chen , Lingwei Zhu , Yushun Dong , Yasuko Matsubara , Yasushi Sakurai

In this work, we introduce a definition of the Discrete Fourier Transform (DFT) on Euclidean lattices in $\R^n$, that generalizes the $n$-th fold DFT of the integer lattice $\Z^n$ to arbitrary lattices. This definition is not applicable for…

Quantum Physics · Physics 2017-04-04 Lior Eldar , Peter Shor

Multivariate spatial-statistical models are often used when modeling environmental and socio-demographic processes. The most commonly used models for multivariate spatial covariances assume both stationarity and symmetry for the…

Methodology · Statistics 2021-05-11 Quan Vu , Andrew Zammit-Mangion , Noel Cressie

Background: Windowed Fourier decompositions (WFD) are widely used in measuring stationary and non-stationary spectral phenomena and in describing pairwise relationships among multiple signals. Although a variety of WFDs see frequent…

Quantitative Methods · Quantitative Biology 2019-01-30 Christopher K. Kovach , Phillip E. Gander

A novel approach towards the spectral analysis of stationary random bivariate signals is proposed. Using the Quaternion Fourier Transform, we introduce a quaternion-valued spectral representation of random bivariate signals seen as…

Methodology · Statistics 2017-11-22 Julien Flamant , Nicolas Le Bihan , Pierre Chainais

Standard geostatistical models assume stationarity and rely on a variogram model to account for the spatial dependence in the observed data. In some instances, this assumption that the spatial dependence structure is constant throughout the…

Methodology · Statistics 2022-12-16 Dave Higdon , Jenise Swall , John Kern

Measuring sediment transport in riverbeds has long been a challenging research problem in geomorphology and river engineering. Traditional approaches rely on direct measurements using sediment samplers. Although such measurements are often…

Systems and Control · Electrical Eng. & Systems 2026-03-31 Shakib Mustavee , Arvind Singh , Shaurya Agarwal

Bayesian inference for stationary random fields is computationally demanding. Whittle-type likelihoods in the frequency domain based on the fast Fourier Transform (FFT) have several appealing features: i) low computational complexity of…

Methodology · Statistics 2025-05-30 Thomas Goodwin , Arthur Guillaumin , Matias Quiroz , Mattias Villani , Robert Kohn

We address the problem of predicting spatio-temporal processes with temporal patterns that vary across spatial regions, when data is obtained as a stream. That is, when the training dataset is augmented sequentially. Specifically, we…

Machine Learning · Statistics 2018-06-25 Muhammad Osama , Dave Zachariah , Thomas B. Schön

Channel estimation is one of the most important parts in current mobile communication systems. Among the huge contributions in channel estimation studies, the discrete Fourier transform (DFT)-based channel estimation has attracted lots of…

Information Theory · Computer Science 2015-04-29 H. Yu , C. Yang

Knowledge on evolving physical fields is of paramount importance in science, technology, and economics. Dynamical field inference (DFI) addresses the problem of reconstructing a stochastically driven, dynamically evolving field from finite…

Quantum Physics · Physics 2021-12-22 Margret Westerkamp , Igor Ovchinnikov , Philipp Frank , Torsten Enßlin

The advent of data science has provided an increasing number of challenges with high data complexity. This paper addresses the challenge of space-time data where the spatial domain is not a planar surface, a sphere, or a linear network, but…

Methodology · Statistics 2022-08-09 Emilio Porcu , Philip A. White , Marc G. Genton

We give some new results related to the directional short-time Fourier transform (DSTFT) and extend them on the spaces $\mathcal K_{1}(\mathbb R^{n})$ and $\mathcal K_{1}({\mathbb R})\widehat{\otimes}\mathcal U(\mathbb C^n)$ and their…

Functional Analysis · Mathematics 2017-08-28 Sanja Atanasova , Stevan Pilipovic , Katerina Saneva

Many studies record replicated time series epochs from different groups with the goal of using frequency domain properties to discriminate between the groups. In many applications, there exists variation in cyclical patterns from time…

Methodology · Statistics 2017-01-19 Robert T. Krafty

This paper introduces a novel technique to preserve spectral features in lossy compression based on a novel fast Fourier correction algorithm\added{ for regular-grid data}. Preserving both spatial and frequency representations of data is…

Distributed, Parallel, and Cluster Computing · Computer Science 2026-01-06 Congrong Ren , Robert Underwood , Sheng Di , Emrecan Kutay , Zarija Lukic , Aylin Yener , Franck Cappello , Hanqi Guo