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It is well-known that magnetohydrodynamic (MHD) turbulence is ubiquitous in astrophysical environments. The correct understanding of the fundamental properties of MHD turbulence is a prerequisite for revealing many key astrophysical…

High Energy Astrophysical Phenomena · Physics 2022-03-18 Jianfu Zhang , Ruyue Wang

White paper: The aim of this work is to apply and analyze machine learning methods for uncertainty quantification of turbulence models. In this work we investigate the classical and data-driven variants of the eigenspace perturbation…

Fluid Dynamics · Physics 2022-11-04 Marcel Matha , Karsten Kucharczyk

We propose a data-driven viscosity solver based on U-shaped convolutional neural network to predict velocity changes due to viscosity. Our solver takes velocity derivatives, fluid volume, and solid indicator quantities as input. The…

Graphics · Computer Science 2024-09-24 Wonjung Park , Hyunsoo Kim , Jinah Park

Turbulence is a complex system exhibiting both universal statistical features and prominent coherent structures. We model turbulence using coherent vortices distributed within a multi-scale statistical framework, termed `woven turbulence'.…

Fluid Dynamics · Physics 2025-12-04 Zishuo Han , Weiyu Shen , Yue Yang

Recent studies provide evidence for the multi-scale nature of magnetic turbulence in the plasma sheet. Wavelet methods represent modern time series analysis techniques suitable for the description of statistical characteristics of…

Space Physics · Physics 2016-09-08 W. Baumjohann , R. Nakamura , A. Runov , M. Volwerk , T. L. Zhang , A. Balogh

Emerging connected vehicle (CV) data sets have recently become commercially available. This paper presents several tools using CV data to evaluate traffic progression quality along a signalized corridor. These include both performance…

Human-Computer Interaction · Computer Science 2023-06-21 Shoaib Mahmud , Christopher M. Day

Context --- The classical method to infer microturbulent velocity in stellar spectra requires that the abundances of the iron lines are not correlated with the observed equivalent widths. An alternative method, requiring the use of the…

Solar and Stellar Astrophysics · Physics 2015-05-27 Alessio Mucciarelli

We present high resolution simulations of two-fluid (ion-neutral) MHD turbulence with resolutions as large as 512^3. The simulations are supersonic and mildly sub-Alfvenic, in keeping with the conditions present in molecular clouds. Such…

Astrophysics of Galaxies · Physics 2015-06-16 Chad D. Meyer , Dinshaw S. Balsara , Blakesley Burkhart , Alex Lazarian

Quantitatively mapping three-dimensional (3D) flow, diffusion, and particle density in crowded living cells remains challenging because most dynamic optical microscopy measurements are effectively planar and existing analysis methods…

Quantitative Methods · Quantitative Biology 2026-03-31 Ahmad Mahmood , Paul W. Wiseman

Motivated by previous work on kinetic energy cascades in the ocean and atmosphere, we develop a spatio-temporal spectral transfer tool that can be used to study scales of variability in generalized dynamical systems. In particular, we use…

The energy cascade rate of turbulence can be measured with the structure function. In practice, the 3D velocity of the gas in molecular cloud is hard to measure, which makes the measurement of structure function difficult. In the case of…

Astrophysics of Galaxies · Physics 2021-06-16 Lei Qian

With the emergence of high-frequency connected and automated vehicle data, analysts have become able to extract useful information from them. To this end, the concept of "driving volatility" is defined and explored as deviation from the…

Applications · Statistics 2018-05-16 Mohsen Kamrani , Ramin Arvin , Asad J. Khattak

An autoencoder is used to compress and then reconstruct three-dimensional stratified turbulence data in order to better understand fluid dynamics by studying the errors in the reconstruction. The original single data set is resolved on…

Fluid Dynamics · Physics 2019-07-29 S. M. de Bruyn Kops , D. J. Saunders , E. A. Rietman , G. D. Portwood

In this work we investigate the Principal Component Analysis (PCA) sensitivity to the velocity power spectrum in high opacity regimes of the interstellar medium (ISM). For our analysis we use synthetic Position-Position-Velocity (PPV) cubes…

Velocity anisotropy induced by MHD turbulence is investigated using computational simulations and molecular line observations of the Taurus molecular cloud. A new analysis method is presented to evaluate the degree and angle of velocity…

Astrophysics · Physics 2009-11-13 Mark Heyer , Hao Gong , Eve Ostriker , Christopher Brunt

Turbulence influences the structure and dynamics of molecular clouds, and plays a key role in regulating star formation. We therefore need methods to accurately infer turbulence properties of molecular clouds from position-position-velocity…

Astrophysics of Galaxies · Physics 2025-09-12 Jayashree Narayan , Aris Tritsis , Christoph Federrath

We present the first application of the angle-dependent 3-Point Correlation Function (3PCF) to the density fields magnetohydrodynamic (MHD) turbulence simulations intended to model interstellar (ISM) turbulence. Previous work has…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-03 Stephen K. N. Portillo , Zachary Slepian , Blakesley Burkhart , Sule Kahraman , Douglas P. Finkbeiner

Transportation is a major contributor to CO2 emissions, making it essential to optimize traffic networks to reduce energy-related emissions. This paper presents a novel approach to traffic network control using Differentiable Predictive…

Systems and Control · Electrical Eng. & Systems 2024-06-18 Renukanandan Tumu , Wenceslao Shaw Cortez , Ján Drgoňa , Draguna L. Vrabie , Sonja Glavaski

Synthetic turbulence is a relevant tool to study complex astrophysical and space plasma environments inaccessible by direct simulation. However, conventional models lack intermittent coherent structures, which are essential in realistic…

Space Physics · Physics 2024-05-08 Jeremiah Lübke , Frederic Effenberger , Mike Wilbert , Horst Fichtner , Rainer Grauer

Motion of particles (bodies) in presence of random effects can be considered stochastic process. However, application of widely known stochastic processes used for description of particle motion is reduced to relatively small class of…

General Physics · Physics 2022-04-14 Jiri Prochazka