arXiv Machine Learning

Origins and mitigation of double descent in reduced order modeling

arXiv:2607. 26414v1 Announce Type: cross Abstract: Latent low-dimensional structure in datasets of natural and engineered systems enables their sparse sensing, or full-state reconstruction from historical data and very few carefully chosen localized measurements.

arXiv Machine Learning
Sep 16

Recovering Physical Parameters from Fragmented Observations via Exact Distributed Spline Merging

The paper presents a method for merging fragmented scientific observations into a continuous, differentiable field without sharing raw data or requiring iterative synchronization. By leveraging the additive structure of fixed-basis ridge-regression statistics, each data holder computes local Gram matrices and moment vectors, producing a merged solution mathematically identical to centralized fitting. The authors demonstrate a complete pipeline that reconstructs the field, extracts derivatives, and performs linear regression to infer physical parameters, achieving sub‑percent errors in recovering diffusion coefficients and wave speeds, and validate the approach on 41 years of NOAA sea‑surface temperature data.

By Naveen Mysore
arXiv Machine Learning
Sep 18

Recovering Governing Dynamics from Distributed Observations via Exact Spline Merging

The paper presents a method for merging distributed observations into a continuous, differentiable spline field without sharing raw data or iterative synchronization. By leveraging fixed-basis ridge regression, each data holder computes local Gram matrices and moment vectors, and the merged solution matches centralized fitting exactly. The authors validate the pipeline on four PDEs and real NOAA sea‑surface temperature data, achieving sub‑percent accuracy for linear cases and 5% for the nonlinear Burgers equation, with no degradation from distributed merging.

By Naveen Mysore
arXiv Machine Learning
Aug 19

Estimating Parameter Fields in Multi-Physics PDEs from Scarce Measurements

The paper introduces Neptune, a method that uses independent coordinate neural networks to infer parameter fields in multi-physics PDEs from sparse measurements. Neptune can accurately estimate parameters with nonlinear, spatiotemporal variations, outperforming existing techniques by reducing estimation errors by up to two orders of magnitude and improving dynamic response predictions by a factor of ten. It also demonstrates strong physical extrapolation, enabling reliable predictions beyond the training data.

By Xuyang Li, Mahdi Masmoudi, Rami Gharbi, Nizar Lajnef, Vishnu Naresh Boddeti
arXiv AI
Jul 22

Incomplete Observations Boost Evolutionary Performance in Ocean Modeling

arXiv:2607. 19147v1 Announce Type: cross Abstract: Data-driven methods have revolutionized ocean modeling, yet current approaches rely heavily on complete reanalysis datasets, imposing computational constraints and limiting model performance to that of the training data.

By Yangyang Kong, Yutong Jiang, Yanhai Gan, Junyu Dong, Feng Gao, Xiaopei Lin
arXiv Machine Learning
Aug 11

NeuralDMD: Interpretable Neural Representation of Dynamics from Sparse and Noisy Measurements

arXiv:2507. 03094v2 Announce Type: replace-cross Abstract: Many challenges in scientific imaging involve solving ill-posed inverse problems, where the goal is to recover spatio-temporal fields from indirect, noisy, and highly sparse measurements - often without access to ground truth data or reliable simulators.

By Ali SaraerToosi, Renbo Tu, Esther Y. H. Lin, Kamyar Azizzadenesheli, Aviad Levis
arXiv Machine Learning
Sep 14

Physical-State-Guided Diffusion Sampling for Full-Waveform Inversion

Physical-State-Guided Diffusion Sampling (PSG) couples a persistent physical velocity model to a diffusion prior via a Gaussian bridge, allowing the physical state to be refined by waveform fitting while guiding the reverse diffusion process. This approach separates wave‑equation and denoiser gradients, preserving conventional FWI initialization and optimization history. PSG outperforms classical and diffusion‑based baselines on four OpenFWI families, maintains strong structural recovery under noise, and supports large‑scale models like Marmousi, Overthrust, and BP2004 Salt without retraining.

By Chen Min, Haowen Jiang, Zheng Ma, Xiongbin Yan
arXiv Machine Learning
Aug 28

TRACE: Retrospective Streaming Generation of Physical Fields under Sparse Structured Sensing

TRACE is a retrospective streaming generative reconstruction framework designed to recover continuous physical fields from sparse, structured sensing streams. It performs approximate Bayesian inference in a continuous-coordinate latent space, fuses sparse off‑grid measurements with a state‑space temporal prior via Kalman‑style filtering, and refines past frames through retrospective smoothing. Experiments on active matter, ocean sound‑speed fields, and supernova simulations demonstrate that TRACE matches or surpasses existing frame‑wise generative reconstructors, offline spatiotemporal methods, and streaming data‑assimilation baselines in reconstruction quality under temporally sparse and spatially localized sensing protocols.

By Xinyu Zhang, Lihao Chen, Panqi Chen, Lei Cheng, Ting Zhang, Jianlong Li, Shikai Fang
arXiv Machine Learning
Sep 16

Improving Reduced-Order Rotating Detonation Engine Models with Data Assimilation and Machine Learning

The paper presents a method to enhance one‑dimensional rotating detonation engine (RDE) models by integrating data assimilation and machine learning. Continuous data assimilation (nudging) aligns the low‑order Koch‑Kutz solver with high‑fidelity temperature data, while a Jacobian‑regularized closure is trained on the recorded correction forces. The resulting corrected model, once the observation term is removed, autonomously reproduces the temperature spectrum and key statistical properties of the full high‑fidelity simulation.

By Ashwin Suriyanarayanan, Romit Maulik