English
Related papers

Related papers: Structure analysis of interstellar clouds: I. Impr…

200 papers

The present paper reports on our effort to characterize vortical interactions in complex fluid flows through the use of network analysis. In particular, we examine the vortex interactions in two-dimensional decaying isotropic turbulence and…

Fluid Dynamics · Physics 2017-05-23 Kunihiko Taira , Aditya G. Nair , Steven L. Brunton

In analogy with steerable wavelets, we present a general construction of adaptable tight wavelet frames, with an emphasis on scaling operations. In particular, the derived wavelets can be "dilated" by a procedure comparable to the operation…

Computer Vision and Pattern Recognition · Computer Science 2017-06-20 Zsuzsanna Püspöki , John Paul Ward , Daniel Sage , Michael Unser

The problem of the harmonic oscillator with a centrally located delta function potential can be exactly solved in one dimension where the eigenfunctions are expressed as superpositions of the Hermite polynomials or as confluent…

Quantum Physics · Physics 2021-08-18 Indrajit Ghose , Parongama Sen

Matrix valued data has become increasingly prevalent in many applications. Most of the existing clustering methods for this type of data are tailored to the mean model and do not account for the dependence structure of the features, which…

Machine Learning · Statistics 2023-12-07 Inbeom Lee , Siyi Deng , Yang Ning

We present a general framework for matching the point-spread function (PSF), photometric scaling, and sky background between two images, a subject which is commonly referred to as difference image analysis (DIA). We introduce the new…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 D. M. Bramich , Keith Horne , M. D. Albrow , Y. Tsapras , C. Snodgrass , R. A. Street , M. Hundertmark , Noe Kains , A. Arellano Ferro , R. Figuera Jaimes , Sunetra Giridhar

In this work, we study the nonlinear traveling waves in density stratified fluids with depth varying shear currents. Beginning the formulation of the water-wave problem due to [1], we extend the work of [4] and [18] to examine the interface…

Fluid Dynamics · Physics 2017-08-30 K. L. Oliveras , C. W. Curtis

The empirical wavelet transform is an adaptive multiresolution analysis tool based on the idea of building filters on a data-driven partition of the Fourier domain. However, existing 2D extensions are constrained by the shape of the…

Spectral Theory · Mathematics 2024-10-28 Basile Hurat , Zariluz Alvarado , Jerome Gilles

In this Letter we present discrete wave turbulence (DWT) as a counterpart of classical statistical wave turbulence (SWT). DWT is characterized by resonance clustering, not by the size of clusters, i.e. it includes, but is not reduced to,…

Fluid Dynamics · Physics 2009-09-07 Elena Kartashova

This two-part review summarizes interstellar turbulence and its implications. The first part begins with diagnostics and energy sources. Turbulence theory is considered in detail, including the basic fluid equations, solenoidal and…

Astrophysics · Physics 2008-11-26 Bruce G. Elmegreen , John Scalo

Based on the theoretical description of Position-Position-Velocity(PPV) statistics in Lazarian & Pogosyan(2000), we introduce a new technique called the Velocity Decomposition Algorithm(VDA) in separating the PPV fluctuations arising from…

Astrophysics of Galaxies · Physics 2021-04-14 Ka Ho Yuen , Ka Wai Ho , Alex Lazarian

Long global gyrokinetic turbulence simulations are particularly challenging in situations where the system deviates strongly from its initial state and when fluctuation level are high e.g. in strong gradient regions. For Particle-in-Cell…

A fully-convolutional neural-network model is used to predict the streamwise velocity fields at several wall-normal locations by taking as input the streamwise and spanwise wall-shear-stress planes in a turbulent open channel flow. The…

Fluid Dynamics · Physics 2020-08-26 L. Guastoni , M. P. Encinar , P. Schlatter , H. Azizpour , R. Vinuesa

This paper presents a multi-dimensional computational method to predict the spatial variation data inside and across multiple dies of a wafer. This technique is based on tensor computation. A tensor is a high-dimensional generalization of a…

Machine Learning · Computer Science 2019-01-04 Jiali Luan , Zheng Zhang

3D point clouds deep learning is a promising field of research that allows a neural network to learn features of point clouds directly, making it a robust tool for solving 3D scene understanding tasks. While recent works show that point…

Computer Vision and Pattern Recognition · Computer Science 2022-03-22 Zhiyuan Zhang , Binh-Son Hua , Sai-Kit Yeung

This paper proposes a robust test for assessing isotropy based on the variogram of spatial data on a two-dimensional regular grid. The test is based on the non-robust subsampling test for isotropy of Guan et al. (2004), which uses the idea…

Methodology · Statistics 2026-05-19 Jana Gierse , Roland Fried

We apply a novel method with machine learning to calibrate sub-grid models within numerical simulation codes to achieve convergence with observations and between different codes. It utilizes active learning and neural density estimators.…

Astrophysics of Galaxies · Physics 2022-10-07 Boon Kiat Oh , Hongjun An , Eun-jin Shin , Ji-hoon Kim , Sungwook E. Hong

Three dimensional (3D) object recognition is becoming a key desired capability for many computer vision systems such as autonomous vehicles, service robots and surveillance drones to operate more effectively in unstructured environments.…

Computer Vision and Pattern Recognition · Computer Science 2021-08-25 Chenxi Xiao , Juan Wachs

To derive the convergence field from the gravitational shear (gamma) of the background galaxy images, the classical methods require a convolution of the shear to be performed over the entire sky, usually expressed thanks to the Fast Fourier…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 E. Deriaz , J. -L. Starck , S. Pires

Synthetic turbulence models are a useful tool that provide realistic representations of turbulence, necessary to test theoretical results, to serve as background fields in some numerical simulations, and to test analysis tools. Models of 1D…

Fluid Dynamics · Physics 2016-11-15 Francesco Malara , Francesca Di Mare , Giuseppina Nigro , Luca Sorriso-Valvo

Small-scale magnetic turbulence observed by the Cluster spacecraft in the plasma sheet is investigated by means of a wavelet estimator suitable for detecting distinct scaling characteristics even in noisy measurements. The spectral…