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Related papers: Nonlinear Reconstruction of the Velocity Field

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Conventional methods for outdoor environment reconstruction rely predominantly on vision-based techniques like photogrammetry and LiDAR, facing limitations such as constrained coverage, susceptibility to environmental conditions, and high…

Networking and Internet Architecture · Computer Science 2024-04-13 Hrant Khachatrian , Rafayel Mkrtchyan , Theofanis P. Raptis

We present a new reconstruction of the mass density and the peculiar velocity fields in the nearby universe using recent measurements of Tully-Fisher distances for a sample of late spirals. We find significant differences between our…

Context. Kinematical data such as the mean velocities and velocity dispersions of stellar samples are useful tools to study galactic structure and evolution. However, observational data are often incomplete (e.g., lacking the radial…

Instrumentation and Methods for Astrophysics · Physics 2013-02-19 Toktam Aghajani , Lennart Lindegren

We present a fast iterative FFT-based reconstruction algorithm that allows for non- parallel redshift-space distortions (RSD). We test our algorithm on both N-body dark matter simulations and mock distributions of galaxies designed to…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-17 Angela Burden , Will J. Percival , Cullan Howlett

Wind speed at sea surface is a key quantity for a variety of scientific applications and human activities. Due to the non-linearity of the phenomenon, a complete description of such variable is made infeasible on both the small scale and…

Machine Learning · Computer Science 2024-10-28 Matteo Zambra , Nicolas Farrugia , Dorian Cazau , Alexandre Gensse , Ronan Fablet

The sparse layouts of radio interferometers result in an incomplete sampling of the sky in Fourier space which leads to artifacts in the reconstructed images. Cleaning these systematic effects is essential for the scientific use of…

Instrumentation and Methods for Astrophysics · Physics 2023-07-27 Kevin Schmidt , Felix Geyer , Stefan Fröse , Paul-Simon Blomenkamp , Marcus Brüggen , Francesco de Gasperin , Dominik Elsässer , Wolfgang Rhode

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

Velocity-encoded MRI is an imaging technique used in different areas to assess flow motion. Some applications include medical imaging such as cardiovascular blood flow studies, and industrial settings in the areas of rheology, pipe flows,…

Image and Video Processing · Electrical Eng. & Systems 2019-08-16 Veronica Corona , Martin Benning , Lynn F. Gladden , Andi Reci , Andrew J. Sederman , Carola-Bibiane Schoenlieb

We develop a computational method based on an Eulerian field called the "reference map", which relates the current location of a material point to its initial. The reference map can be discretized to permit finite-difference simulation of…

Soft Condensed Matter · Physics 2009-05-07 Ken Kamrin , Jean-Christophe Nave

We investigate the purely spatial Lagrangian coordinate transformation from the Lagrangian to the basic Eulerian frame. We demonstrate three techniques for extracting the relativistic displacement field from a given solution in the…

General Relativity and Quantum Cosmology · Physics 2014-12-16 Cornelius Rampf , Alexander Wiegand

Directional wave speeds variations in anisotropic elastic solids enables material characterisation capabilities, such as determination of elastic constants and volumetric measurement of crystallographic texture. However, achieving such…

Applied Physics · Physics 2024-08-19 Melody Png , Ming Huang , Marzieh Bahreman , Christopher M. Kube , Michael J. S. Lowe , Bo Lan

Although Potent purports to use only radial velocities in reconstructing the potential velocity field of galaxies, the derivation of transverse components is implicit in the smoothing procedures adopted. Thus the possibility arises of using…

Astrophysics · Physics 2007-05-23 J. F. L. Simmons , A. Newsam , M. A. Hendry

Large-scale Fourier modes of the cosmic density field are of great value for learning about cosmology because of their well-understood relationship to fluctuations in the early universe. However, cosmic variance generally limits the…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-05 Omar Darwish , Simon Foreman , Muntazir M. Abidi , Tobias Baldauf , Blake D. Sherwin , P. Daniel Meerburg

We present a general paradigm for dynamic 3D reconstruction from multiple independent and uncontrolled image sources having arbitrary temporal sampling density and distribution. Our graph-theoretic formulation models the Spatio-temporal…

Computer Vision and Pattern Recognition · Computer Science 2019-08-30 Xiangyu Xu , Enrique Dunn

Reconstruction techniques are commonly used in cosmology to reduce complicated nonlinear behaviours to a more tractable linearized system. We study a new reconstruction technique that uses the Moving-Mesh algorithm to estimate the…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-21 Qiaoyin Pan , Ue-Li Pen , Derek Inman , Hao-Ran Yu

We present a hybrid particle/grid approach for simulating incompressible fluids on collocated velocity grids. We interchangeably use particle and grid representations of transported quantities to balance efficiency and accuracy. A novel…

We propose R3GS, a robust reconstruction and relocalization framework tailored for unconstrained datasets. Our method uses a hybrid representation during training. Each anchor combines a global feature from a convolutional neural network…

Computer Vision and Pattern Recognition · Computer Science 2025-05-22 Xu yan , Zhaohui Wang , Rong Wei , Jingbo Yu , Dong Li , Xiangde Liu

With the recent trend for ultra high definition displays, the demand for high quality and efficient video super-resolution (VSR) has become more important than ever. Previous methods adopt complex motion compensation strategies to exploit…

Image and Video Processing · Electrical Eng. & Systems 2019-09-19 Dario Fuoli , Shuhang Gu , Radu Timofte

We present a new formulation of Lagrangian perturbation theory which allows accurate predictions of the real- and redshift-space correlation functions of the mass field and dark matter halos. Our formulation involves a non-perturbative…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Jordan Carlson , Beth Reid , Martin White

We studied the reconstruction of turbulent flow fields from trajectory data recorded by actively migrating Lagrangian agents. We propose a deep-learning model, track-to-flow (T2F), which employs a vision transformer as the encoder to…

Fluid Dynamics · Physics 2026-01-15 Hua-Lin Wu , Ao Xu , Heng-Dong Xi