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Related papers: SPARSE-R: A point-cloud tracer with random forcing

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In this paper a LES model with Lagrangian representation of microphysics is used to simulate stratucumulus clouds in idealized 2D set-up based on the VOCALS observations. The general features of the cloud simulated by the model, such as…

Atmospheric and Oceanic Physics · Physics 2012-11-02 M. Andrejczuk , A. Gadian , A. Blyth

Point cloud analysis without pose priors is very challenging in real applications, as the orientations of point clouds are often unknown. In this paper, we propose a brand new point-set learning framework PRIN, namely, Point-wise Rotation…

Computer Vision and Pattern Recognition · Computer Science 2021-11-23 Yang You , Yujing Lou , Ruoxi Shi , Qi Liu , Yu-Wing Tai , Lizhuang Ma , Weiming Wang , Cewu Lu

A reward-guided, gradient-free ParVI method, \textit{R-ParVI}, is proposed for sampling partially known densities (e.g. up to a constant). R-ParVI formulates the sampling problem as particle flow driven by rewards: particles are drawn from…

Artificial Intelligence · Computer Science 2025-03-03 Yongchao Huang

Collisional growth of droplets, such as occurring in warm clouds, is known to be significantly enhanced by turbulence. Whether particles collide depends on their flow history, in particular on their encounters with highly intermittent…

Fluid Dynamics · Physics 2023-08-16 Tobias Bätge , Itzhak Fouxon , Michael Wilczek

In this work, model closures of the multiphase Reynolds-Average Navier-Stokes (RANS) equations are developed for homogeneous, fully-developed gas--particle flows. To date, the majority of RANS closures are based on extensions of…

Fluid Dynamics · Physics 2021-07-07 S. Beetham , R. O. Fox , J. Capecelatro

We developed a new explicit cloud microphysical model, based on direct numerical simulation (DNS) with Lagrangian particle tracking. The model employs a vertically-elongated quasi-1D computational domain extending from the ground to the…

Atmospheric and Oceanic Physics · Physics 2026-04-14 Masaya Iwashima , Ryo Onishi

This paper is a continuation of the work presented in [Chertock et al., Math. Cli. Weather Forecast. 5, 1 (2019), 65--106]. We study uncertainty propagation in warm cloud dynamics of weakly compressible fluids. The mathematical model is…

Numerical Analysis · Mathematics 2023-03-22 A. Chertock , A. Kurganov , M. Lukáčová-Medviďová , P. Spichtinger , B. Wiebe

We study the spreading of viruses, such as SARS-CoV-2, by airborne aerosols, via a new first-passage-time problem for Lagrangian tracers that are advected by a turbulent flow: By direct numerical simulations of the three-dimensional (3D)…

Fluid Dynamics · Physics 2020-08-19 Akhilesh Kumar Verma , Akshay Bhatnagar , Dhrubaditya Mitra , Rahul Pandit

3D point clouds are increasingly vital for applications like autonomous driving and robotics, yet the raw data captured by sensors often suffer from noise and sparsity, creating challenges for downstream tasks. Consequently, point cloud…

Computer Vision and Pattern Recognition · Computer Science 2024-11-04 Donghyun Kim , Hyeonkyeong Kwon , Yumin Kim , Seong Jae Hwang

Lagrangian Coherent Structures (LCS) are flow features which are defined to objectively characterize complex fluid behavior over a finite time regardless of the orientation of the observer. Fluidic applications of LCS include geophysical,…

Fluid Dynamics · Physics 2023-10-18 Tanner D. Harms , Steven L. Brunton , Beverley J. McKeon

Current learning-based methods predict NeRF or 3D Gaussians from point clouds to achieve photo-realistic rendering but still depend on categorical priors, dense point clouds, or additional refinements. Hence, we introduce a novel point…

Computer Vision and Pattern Recognition · Computer Science 2025-05-15 Ma Changfeng , Bi Ran , Guo Jie , Wang Chongjun , Guo Yanwen

Most adversarial attacks on point clouds perturb a large number of points, causing widespread geometric changes and limiting applicability in real-world scenarios. While recent works explore sparse attacks by modifying only a few points,…

Cryptography and Security · Computer Science 2025-12-16 Keke Tang , Tianyu Hao , Xiaofei Wang , Weilong Peng , Denghui Zhang , Peican Zhu , Zhihong Tian

Rigid Point Cloud Registration (PCR) algorithms aim to estimate the 6-DOF relative motion between two point clouds, which is important in various fields, including autonomous driving. Recent years have seen a significant improvement in…

Computer Vision and Pattern Recognition · Computer Science 2022-11-28 Amnon Drory , Shai Avidan , Raja Giryes

We have developed a new experimental technique to measure the Lagrangian velocity of tracer particles in a turbulent flow, based on ultrasonic Doppler tracking. This method yields a direct access to the velocity of a single particule at a…

Fluid Dynamics · Physics 2009-11-07 N. Mordant , P. Metz , O. Michel , J. -F. Pinton

In this paper, we present a new self-supervised scene flow estimation approach for a pair of consecutive point clouds. The key idea of our approach is to represent discrete point clouds as continuous probability density functions using…

Computer Vision and Pattern Recognition · Computer Science 2022-03-24 Pan He , Patrick Emami , Sanjay Ranka , Anand Rangarajan

The turbulent diffusion of Lagrangian tracer particles has been studied in a flow on the surface of a large tank of water and in computer simulations. The effect of flow compressibility is captured in images of particle fields. The velocity…

Chaotic Dynamics · Physics 2009-11-10 John R. Cressman , Walter I. Goldburg , Joerg Schumacher

We investigate the shock-induced flow through random particle arrays using particle-resolved Large Eddy Simulations for different incident shock wave Mach numbers, particle volume fractions and particle sizes. We analyze trends in mean flow…

A computationally efficient model is introduced to account for the sub-grid scale velocities of tracer particles dispersed in statistically homogeneous and isotropic turbulent flows. The model embeds the multi-scale nature of turbulent…

Fluid Dynamics · Physics 2015-06-18 I. M. Mazzitelli , F. Toschi , A. S. Lanotte

Compressing massive LiDAR point clouds in real-time is critical to autonomous machines such as drones and self-driving cars. While most of the recent prior work has focused on compressing individual point cloud frames, this paper proposes a…

Image and Video Processing · Electrical Eng. & Systems 2020-08-18 Yu Feng , Shaoshan Liu , Yuhao Zhu

Distributed models to forecast the spatial and temporal occurrence of rainfall-induced shallow landslides are based on deterministic laws. These models extend spatially the static stability models adopted in geotechnical engineering, and…

Geophysics · Physics 2014-03-17 S. Raia , M. Alvioli , M. Rossi , R. L. Baum , J. W. Godt , F. Guzzetti