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Related papers: New insights from inside-out Doppler tomography

200 papers

A composite representation of the turbulent boundary-layer velocity profile is proposed, which combines a recently determined accurate interpolation of the universal law of the wall with a simple analytical expression of the smooth…

Fluid Dynamics · Physics 2017-09-05 Paolo Luchini

We develop a new method to estimate the area, and more generally the intrinsic volumes, of a compact subset $X$ of $\mathbb{R}^d$ from a set $Y$ that is close in the Hausdorff distance. This estimator enjoys a linear rate of convergence as…

Metric Geometry · Mathematics 2024-07-22 David Cohen-Steiner , Antoine Commaret

Doppler radars are routinely used for the remote sensing of oceanic surface currents and atmospheric wind profiles. Even though they operate at different frequencies and address different media, they follow very similar processing for the…

Atmospheric and Oceanic Physics · Physics 2021-02-02 Baptiste Domps , Julien Marmain , Charles-Antoine Guérin

In this article we give an account of a method of smoothing spatial inhomogeneous data sets by using wavelet reconstruction on a regular grid in an auxilliary space onto which the original data is mapped. In a previous paper by the present…

Astrophysics · Physics 2009-10-28 S. Rauzy , M. Lachièze-Rey , R. N. Henriksen

This work considers current potential uses of laser Doppler velocimetry. A discussion of other optical velocimetry techniques is presented and compared with their practical application to modern shock physics diagnostics, such as VISAR.

Optics · Physics 2007-05-23 W. T. Buttler , S. K. Lamoreaux , F. G. Omenetto , J. R. Torgerson

A new measuring technique dedicated to bubble velocity and size measurements in complex bubbly flows such as those occurring in bubble columns is proposed. This sensor combines the phase detection capability of a conical optical fiber, with…

Fluid Dynamics · Physics 2021-09-17 Anthony Lefebvre , Yann Mezui , Martin Obligado , Stéphane Gluck , Alain Cartellier

We give a critical analysis of the conceptual foundations of special relativity. We formulate a simple operational criterion for distinguishing between noninertial and inertial frames which is introduced prior to geometry. We associate the…

General Relativity and Quantum Cosmology · Physics 2009-06-30 Andrew E. Chubykalo , Augusto Espinoza , B. P. Kosyakov

In this first paper from forthcoming series of works devoted to radio image of relativistic jets from active galactic nuclei the role of internal structure of a flow is discussed. We determine the radial profiles of all physical values for…

High Energy Astrophysical Phenomena · Physics 2019-12-12 A. V. Chernoglazov , V. S. Beskin , V. I. Pariev

Expanding our previous work on turbulent whirls [1] we have uncovered a similarity within the similarity shared by intense vortices. Using the new information we compress the tangential velocity profiles of a diverse set of vortices into…

Astrophysics of Galaxies · Physics 2010-12-08 Georgios H. Vatistas

We demonstrate the capability of Principal Component Analysis (PCA) as applied by Heyer & Schloerb (1997) to extract the statistics of turbulent interstellar velocity fields as measured by the energy spectrum, E(k)= k^-beta. Turbulent…

Astrophysics · Physics 2007-05-23 C. Brunt , M. H. Heyer

Literature mentions only incidentally a sub-Doppler contribution in the excitation spectrum of the backward fluorescence of a dense vapor. This contribution is here investigated on Cs vapor, both on the first resonance line (894 nm) and on…

We assume the spacetime foam picture in which vacuum is filled with virtual wormholes. In the presence of an external field the distribution of wormholes changes. We consider an anisotropic distribution of wormholes and analyze its relation…

General Relativity and Quantum Cosmology · Physics 2016-06-14 E. P. Savelova

The classic imaging geometry for computed tomography is for collection of un-truncated projections and reconstruction of a global image, with the Fourier transform as the theoretical foundation that is intrinsically non-local. Recently,…

Medical Physics · Physics 2015-06-15 Ge Wang , Hengyong Yu

A distinctive feature of Doppler radar is the measurement of velocity in the radial direction for radar points. However, the missing tangential velocity component hampers object velocity estimation as well as temporal integration of radar…

Computer Vision and Pattern Recognition · Computer Science 2021-08-25 Yunfei Long , Daniel Morris , Xiaoming Liu , Marcos Castro , Punarjay Chakravarty , Praveen Narayanan

We propose injective generative models called Trumpets that generalize invertible normalizing flows. The proposed generators progressively increase dimension from a low-dimensional latent space. We demonstrate that Trumpets can be trained…

Machine Learning · Computer Science 2023-07-25 Konik Kothari , AmirEhsan Khorashadizadeh , Maarten de Hoop , Ivan Dokmanić

Having in mind that physical systems have different levels of structure we develop the concept of external, internal and total improper Lorentz transformation (space inversion and time reversal). A particle obtained from the ordinary one by…

High Energy Physics - Phenomenology · Physics 2008-11-26 Matej Pavsic

Velocity statistics is a direct probe of the dynamics of interstellar turbulence. Its observational measurements are very challenging due to the convolution between density and velocity and projection effects. We introduce the projected…

Astrophysics of Galaxies · Physics 2020-01-08 Siyao Xu

We define the notion of mutual quantum measurements of two macroscopic objects and investigate the effect of these measurements on the velocities of the objects. We show that multiple mutual quantum measurements can lead to an effective…

Quantum Physics · Physics 2021-06-23 Walter Hahn , Boris V. Fine

Color Doppler echocardiography enables visualization of blood flow within the heart. However, the limited frame rate impedes the quantitative assessment of blood velocity throughout the cardiac cycle, thereby compromising a comprehensive…

Image and Video Processing · Electrical Eng. & Systems 2024-08-22 Julia Puig , Denis Friboulet , Hang Jung Ling , François Varray , Jonathan Porée , Jean Provost , Damien Garcia , Fabien Millioz

It is proposed to use apertures with large acceptance angles to reduce the integration time when studying the emissivity of laser induced plasmas by means of the Abel inversion method. The spatial resolution lost due to contributions of…

Plasma Physics · Physics 2010-08-02 Sergei Shabanov , Igor Gornushkin