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Related papers: The Centroid Method for Imaging through Turbulence

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Centre manifold techniques are used to derive rationally a description of the dynamics of thin films of fluid. The derived model is based on the free-surface $\eta(x,t)$ and the vertically averaged horizontal velocity $\avu(x,t)$. The…

chao-dyn · Physics 2008-02-03 A. J. Roberts

Seismic traveltime tomography using transmission data is widely used to image the Earth's interior from global to local scales. In seismic imaging, it is used to obtain velocity models for subsequent depth-migration or full-waveform…

Computational Physics · Physics 2021-04-06 Umair bin Waheed , Tariq Alkhalifah , Ehsan Haghighat , Chao Song , Jean Virieux

Atmospheric turbulence significantly affects imaging systems which use light that has propagated through long atmospheric paths. Images captured under such condition suffer from a combination of geometric deformation and space varying blur.…

Computer Vision and Pattern Recognition · Computer Science 2020-07-17 Rajeev Yasarla , Vishal M Patel

We investigate the effect of turbulence on quantum ghost imaging. We use entangled photons and demonstrate that for a novel experimental configuration the effect of turbulence can be greatly diminished. By decoupling the entangled photon…

Turbulent airflow in the atmosphere and the resulting random fluctuations in its refractive index have long been known as a major cause of image deterioration in astronomical imaging and figures among the obstacles for reliable optical…

Quantum Physics · Physics 2015-06-04 Marcelo V. da Cunha Pereira , Luísa A. P. Filpi , Carlos H. Monken

Wave propagation phenomena in soils can be experimentally simulated using centrifuge scale models. An original excitation device (drop-ball arrangement) is proposed to generate short wave trains. Wave reflections on model boundaries are…

Classical Physics · Physics 2009-01-26 J. F. Semblat , M. P. Luong

Atmospheric turbulence in long-range imaging significantly degrades the quality and fidelity of captured scenes due to random variations in both spatial and temporal dimensions. These distortions present a formidable challenge across…

Computer Vision and Pattern Recognition · Computer Science 2024-10-02 Zhicheng Zou , Nantheera Anantrasirichai

The image quality budget of many telescopes can have substantial contributions from local seeing, both``mirror'' and ``dome'', which arise from turbulence and temperature variations that are difficult to quantify, measure directly, and…

Instrumentation and Methods for Astrophysics · Physics 2021-10-13 Christopher W. Stubbs

In this contribution we evaluate the impact of filtering techniques in enhancing the accuracy of forecasts of optical turbulence and atmospheric parameters critical for ground-based telescopes. These techniques make use of the data…

Instrumentation and Methods for Astrophysics · Physics 2019-02-22 A. Turchi , G. Martelloni , E. Masciadri

Atmospheric turbulence degrades image quality by introducing blur and geometric tilt distortions, posing significant challenges to downstream computer vision tasks. Existing single-image and multi-frame methods struggle with the highly…

Computer Vision and Pattern Recognition · Computer Science 2025-08-15 Yixing Liu , Minggui Teng , Yifei Xia , Peiqi Duan , Boxin Shi

GroundBIRD is a ground-based experiment for the precise observation of the polarization of the cosmic microwave background (CMB). To achieve high sensitivity at large angular scale, we adopt three features in this experiment: fast rotation…

The tilted-wave interferometer is a promising technique for the development of a reference measurement system for the highly accurate form measurement of aspheres and freeform surfaces. The technique combines interferometric measurements,…

The excavation process in mechanized tunneling can be improved by reconnaissance of the geology ahead. A nondestructive exploration can be achieved in means of seismic imaging. A full waveform inversion approach, which works in the…

Computational Engineering, Finance, and Science · Computer Science 2022-02-08 Christopher Riedel , Khayal Musayev , Matthias Baitsch , Klaus Hackl

In this work, we extract the optical flow field corresponding to moving objects from an image sequence of a scene impacted by atmospheric turbulence \emph{and} captured from a moving camera. Our procedure first computes the optical flow…

Computer Vision and Pattern Recognition · Computer Science 2024-10-30 Nicholas Ferrante , Jerome Gilles , Shibin Parameswaran

A method of random forcing with a constant power input for two-dimensional gyrokinetic turbulence simulations is developed for the study of stationary plasma turbulence. The property that the forcing term injects the energy at a constant…

Plasma Physics · Physics 2021-03-29 Ryusuke Numata

Theoretical approaches to low-frequency magnetized turbulence in collisionless and weakly collisional astrophysical plasmas are reviewed. The proper starting point for an analytical description of these plasmas is kinetic theory, not fluid…

Astrophysics · Physics 2009-11-11 A. A. Schekochihin , S. C. Cowley , W. Dorland

The dynamic conformal transformation method has been generalized for the first time to numerically simulate the capillary wave turbulence of a liquid surface in the plane symmetric anisotropic geometry. The model is strongly nonlinear and…

Fluid Dynamics · Physics 2024-03-20 Evgeny Kochurin

Advances in data acquisition and numerical wave simulation have improved tomographic imaging techniques and results, but non-experts may find it difficult to understand which model is best for their needs. This paper is intended for these…

Geophysics · Physics 2025-01-27 Andreas Fichtner , Jeroen Ritsema , Solvi Thrastarson

We develop a method based on the cross-spectrum of an intensity-modulated CW laser, which can extract a signal from an extremely noisy environment and image objects hidden in turbid media. We theoretically analyzed our scheme and performed…

An optimal maximum-likelihood technique for computing point-source image centroids from many, slightly offset, CCD frames is presented. The method is especially useful for measuring stellar proper motions from data taken with the Wide Field…

Astrophysics · Physics 2015-06-24 Rodrigo Ibata , Geraint Lewis
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