English
Related papers

Related papers: Lagrangian Gradient Regression for the Detection o…

200 papers

We develop a stochastic model for the velocity gradients dynamics along a Lagrangian trajectory. Comparing with different attempts proposed in the literature, the present model, at the cost of introducing a free parameter known in…

Fluid Dynamics · Physics 2018-02-23 Rodrigo M. Pereira , Luca Moriconi , Laurent Chevillard

We numerically investigate the feasibility and limits of jointly estimating flow fields and unknown particle properties (e.g., position, size, and density) from Lagrangian particle tracking (LPT) data. LPT offers time-resolved, volumetric…

Fluid Dynamics · Physics 2026-05-26 Ke Zhou , Samuel J. Grauer

Embedding parameterized optimization problems as layers into machine learning architectures serves as a powerful inductive bias. Training such architectures with stochastic gradient descent requires care, as degenerate derivatives of the…

Machine Learning · Computer Science 2024-12-16 Anselm Paulus , Georg Martius , Vít Musil

We describe a new method for computing coherent Lagrangian vortices in two-dimensional flows according to any of the following approaches: black-hole vortices [Haller & Beron-Vera, 2013], objective Eulerian Coherent Structures (OECSs)…

Fluid Dynamics · Physics 2020-06-23 Daniel Karrasch , Nathanael Schilling

High-resolution remote sensing images (RSIs) are crucial for Earth observation applications, yet acquiring them is often limited by sensor constraints and costs. In recent years, generative super-resolution (SR) methods, particularly…

Computer Vision and Pattern Recognition · Computer Science 2026-05-22 Jiangwei Mo , Xi Lu , Hanlin Wu

The purpose of this paper is to examine the Lagrangian stochastic modeling of the fluid velocity seen by inertial particles in a nonhomogeneous turbulent flow. A new Langevin-type model, compatible with the transport equation of the drift…

Fluid Dynamics · Physics 2009-07-01 Boris Arcen , Anne Tanière

In this paper we develop new techniques for revealing geometrical structures in phase space that are valid for aperiodically time dependent dynamical systems, which we refer to as Lagrangian descriptors. These quantities are based on the…

Chaotic Dynamics · Physics 2013-08-05 Ana M. Mancho , Stephen Wiggins , Jezabel Curbelo , Carolina Mendoza

To reduce the long training time of large deep neural network (DNN) models, distributed synchronous stochastic gradient descent (S-SGD) is commonly used on a cluster of workers. However, the speedup brought by multiple workers is limited by…

Machine Learning · Computer Science 2020-03-03 Shaohuai Shi , Zhenheng Tang , Qiang Wang , Kaiyong Zhao , Xiaowen Chu

Spatio-temporal forecasting of future values of spatially correlated time series is important across many cyber-physical systems (CPS). Recent studies offer evidence that the use of graph neural networks to capture latent correlations…

Machine Learning · Computer Science 2023-12-29 Minbo Ma , Jilin Hu , Christian S. Jensen , Fei Teng , Peng Han , Zhiqiang Xu , Tianrui Li

Deterministic and probabilistic tools from nonlinear dynamics are used to assess enduring near-surface Lagrangian aspects of the Malvinas Current. The deterministic tools are applied on a multi-year record of velocities derived from…

Atmospheric and Oceanic Physics · Physics 2020-02-19 FJ Beron-Vera , N. Bodnariuk , M. Saraceno , MJ Olascoaga , C Simionato

We propose a sparse regression method capable of discovering the governing partial differential equation(s) of a given system by time series measurements in the spatial domain. The regression framework relies on sparsity promoting…

Pattern Formation and Solitons · Physics 2016-09-22 Samuel H. Rudy , Steven L. Brunton , Joshua L. Proctor , J. Nathan Kutz

A new method for analyzing high-dimensional categorical data, Linear Latent Structure (LLS) analysis, is presented. LLS models belong to the family of latent structure models, which are mixture distribution models constrained to satisfy the…

Probability · Mathematics 2007-06-13 Mikhail Kovtun , Igor Akushevich , Kenneth G. Manton , H. Dennis Tolley

Oceanic surface flows are dominated by finite-time Lagrangian coherent structures that separate regions of qualitatively different dynamical behavior. Among these, eddy boundaries are of particular interest. Their exact identification is…

Atmospheric and Oceanic Physics · Physics 2019-05-17 Benedict Lünsmann , Holger Kantz

This paper presents FLGC, a simple yet effective fully linear graph convolutional network for semi-supervised and unsupervised learning. Instead of using gradient descent, we train FLGC based on computing a global optimal closed-form…

Machine Learning · Computer Science 2021-11-16 Yaoming Cai , Zijia Zhang , Zhihua Cai , Xiaobo Liu , Yao Ding , Pedram Ghamisi

We investigate the response of large inertial particle to turbulent fluctuations in a inhomogeneous and anisotropic flow. We conduct a Lagrangian study using particles both heavier and lighter than the surrounding fluid, and whose diameters…

Fluid Dynamics · Physics 2016-04-20 Nathanaël Machicoane , Romain Volk

We propose the Lowner--John deform-cloud scheme as a Lagrangian diagnostic for incompressible stochastic flows with an inertial range. A volume-filled particle cloud is released at the ultraviolet scale and summarized at each time by two…

Fluid Dynamics · Physics 2026-05-28 Michael Chertkov

A functional (lagged) time series regression model involves the regression of scalar response time series on a time series of regressors that consists of a sequence of random functions. In practice, the underlying regressor curve time…

Methodology · Statistics 2020-07-28 Tomáš Rubín , Victor M. Panaretos

We review and test twelve different approaches to the detection of finite-time coherent material structures in two-dimensional, temporally aperiodic flows. We consider both mathematical methods and diagnostic scalar fields, comparing their…

In this paper, we propose a mass conservative semi-Lagrangian finite difference scheme for multi-dimensional problems without dimensional splitting. The semi-Lagrangian scheme, based on tracing characteristics backward in time from grid…

Numerical Analysis · Mathematics 2016-07-26 Tao Xiong , Giovanni Russo , Jing-Mei Qiu

Computational Fluid Dynamics (CFD) is an indispensable method of fluid modelling in engineering applications, reducing the need for physical prototypes and testing for tasks such as design optimisation and performance analysis. Depending on…