arXiv Machine Learning

Physics-Informed Neural Networks for Depth-Averaged Granular Avalanche Dynamics on Curved Topography

arXiv Machine Learning
Sep 4

TRACE: Spatiotemporal Contact Memory Graph Network Simulator for Granular Dynamics

TRACE is a graph‑network simulator that stores granular contact history on edges using attention‑based message passing and a gated recurrent unit, with an edge‑identity dictionary to preserve memory as contacts change. It predicts normal and tangential forces while enforcing Coulomb friction and internal force balance, and is trained via single‑step pretraining followed by autoregressive fine‑tuning. On 2D and 3D granular column‑collapse benchmarks, TRACE achieves significantly lower long‑rollout position and deposit errors than existing simulators, uses fewer parameters, maintains near‑zero particle interpenetration, and outperforms the material point method by 12.2× (2D) and 8.9× (3D).

By Changjian Zhou, Negin Yousefpour, Jie Qi, Junfeng Fang, Guillermo A. Narsilio, Hans Petter Jostad
arXiv Machine Learning
1d ago

Loading history and window geometry bound compact-state slip ranking during granular shear startup

The study investigates granular slip forecasting by separating material state, loading progress, and window geometry effects using a compact neural score based on stress, pressure, coordination, non-affine motion, and force-network observables. Trained on 36 shear trajectories and tested on 18 new ones, the model ranked near‑slip windows better than prevalence or phase controls, yet loading‑history coordinates (e.g., causal elapsed strain) outperformed the compact score. The findings show that while compact observables contain temporally aligned slip information, stronger loading‑history baselines and geometry sensitivity limit the identification of a state‑specific short‑horizon precursor.

By Ruixin Zhou, Boliang Yu
arXiv Machine Learning
Sep 16

Drift Field Net: Learning Ocean Lagrangian advection fields from in-situ and satellite observations

Drift Field Net (DFN) is a deep neural network that predicts ocean surface flow fields from satellite observations, trained via a two‑stage strategy combining simulated data pretraining and Lagrangian fine‑tuning with an advection‑consistent loss. DFN improves particle trajectory forecasts, reducing mean positioning error by 20 km over a 7‑day period compared to an operational physics‑based model, and further decreasing error by 10 km when the advection loss is applied. The study demonstrates that incorporating Lagrangian constraints into deep‑learning training enhances ocean surface flow prediction accuracy.

By Th\'eo Archambault, Pierre Garcia, Mattia Romero, Anastase Charantonis, Dominique B\'er\'eziat
arXiv AI
Sep 18

Physical knowledge on historical data matters more than enforcing physical constraints on the forecast

The paper introduces a Physics Informed Recurrent Neural Network (PIRNN) that simultaneously predicts target time series and unobservable intermediate physical variables, enhancing robustness and interpretability. It adapts to any physical model with multiple equations and variables, demonstrated on groundwater level predictions using the Gardenia model. Experiments on twelve real‑world datasets show PIRNN outperforming several neural network baselines and the Gardenia model, with an ablation study confirming the value of physical knowledge.

By Etienne Lehembre (CA, LIFO), Pascal Audigane (BRGM), Vincent Nguyen (LIFO), Christel Vrain (LIFO, CA), Thi-Bich-Hanh Dao (LIFO, CA)