physics-based model
Data-Driven Modeling and Correction of Vehicle Dynamics
Ly, Nguyen, Tatsuoka, Caroline, Nagaraj, Jai, Levy, Jacob, Palafox, Fernando, Fridovich-Keil, David, Lu, Hannah
We develop a data-driven framework for learning and correcting non-autonomous vehicle dynamics. Physics-based vehicle models are often simplified for tractability and therefore exhibit inherent model-form uncertainty, motivating the need for data-driven correction. Moreover, non-autonomous dynamics are governed by time-dependent control inputs, which pose challenges in learning predictive models directly from temporal snapshot data. To address these, we reformulate the vehicle dynamics via a local parameterization of the time-dependent inputs, yielding a modified system composed of a sequence of local parametric dynamical systems. We approximate these parametric systems using two complementary approaches. First, we employ the DRIPS (dimension reduction and interpolation in parameter space) methodology to construct efficient linear surrogate models, equipped with lifted observable spaces and manifold-based operator interpolation. This enables data-efficient learning of vehicle models whose dynamics admit accurate linear representations in the lifted spaces. Second, for more strongly nonlinear systems, we employ FML (Flow Map Learning), a deep neural network approach that approximates the parametric evolution map without requiring special treatment of nonlinearities. We further extend FML with a transfer-learning-based model correction procedure, enabling the correction of misspecified prior models using only a sparse set of high-fidelity or experimental measurements, without assuming a prescribed form for the correction term. Through a suite of numerical experiments on unicycle, simplified bicycle, and slip-based bicycle models, we demonstrate that DRIPS offers robust and highly data-efficient learning of non-autonomous vehicle dynamics, while FML provides expressive nonlinear modeling and effective correction of model-form errors under severe data scarcity.
- North America > United States > Texas > Travis County > Austin (0.14)
- North America > United States > Ohio > Franklin County > Columbus (0.04)
- Automobiles & Trucks (0.68)
- Leisure & Entertainment > Sports (0.46)
- Europe > France (0.40)
- Europe > United Kingdom > England > Cambridgeshire > Cambridge (0.04)
- Europe > Spain > Andalusia > Granada Province > Granada (0.04)
- Asia > Japan (0.04)
- Research Report > Experimental Study (1.00)
- Research Report > New Finding (0.68)
How AI can improve storm surge forecasts to help save lives
Hurricanes are America's most destructive natural hazards, causing more deaths and property damage than any other type of disaster. Since 1980, these powerful tropical storms have done more than US$1.5 trillion in damage and killed more than 7,000 people. The No. 1 cause of the damages and deaths from hurricanes is storm surge . Storm surge is the rise in the ocean's water level, caused by a combination of powerful winds pushing water toward the coastline and reduced air pressure within the hurricane compared to the pressure outside of it. In addition to these factors, waves breaking close to the coast causes sea level to increase near the coastline, a phenomenon we call wave setup, which can be an important component of storm surge.
- North America > United States > Florida > Lee County > Fort Myers (0.05)
- Europe > Italy > Emilia-Romagna > Metropolitan City of Bologna > Bologna (0.05)
Stiff Circuit System Modeling via Transformer
Yan, Weiman, Chang, Yi-Chia, Zhao, Wanyu
Accurate and efficient circuit behavior modeling is a cornerstone of modern electronic design automation. Among different types of circuits, stiff circuits are challenging to model using previous frameworks. In this work, we propose a new approach using Crossformer, which is a current state-of-the-art Transformer model for time-series prediction tasks, combined with Kolmogorov-Arnold Networks (KANs), to model stiff circuit transient behavior. By leveraging the Crossformer's temporal representation capabilities and the enhanced feature extraction of KANs, our method achieves improved fidelity in predicting circuit responses to a wide range of input conditions. Experimental evaluations on datasets generated through SPICE simulations of analog-to-digital converter (ADC) circuits demonstrate the effectiveness of our approach, with significant reductions in training time and error rates.
- North America > United States (0.68)
- Asia > China > Beijing > Beijing (0.04)
- Europe > United Kingdom > England > Berkshire > Reading (0.04)
- Asia > Japan (0.04)
- Energy (0.46)
- Government > Regional Government (0.46)
- Research Report > Experimental Study (1.00)
- Research Report > New Finding (0.68)
Benchmarking atmospheric circulation variability in an AI emulator, ACE2, and a hybrid model, NeuralGCM
Baxter, Ian, Pahlavan, Hamid, Hassanzadeh, Pedram, Rucker, Katharine, Shaw, Tiffany
Physics-based atmosphere-land models with prescribed sea surface temperature have notable successes but also biases in their ability to represent atmospheric variability compared to observations. Recently, AI emulators and hybrid models have emerged with the potential to overcome these biases, but still require systematic evaluation against metrics grounded in fundamental atmospheric dynamics. Here, we evaluate the representation of four atmospheric variability benchmarking metrics in a fully data-driven AI emulator (ACE2-ERA5) and hybrid model (NeuralGCM). The hybrid model and emulator can capture the spectra of large-scale tropical waves and extratropical eddy-mean flow interactions, including critical levels. However, both struggle to capture the timescales associated with quasi-biennial oscillation (QBO, $\sim 28$ months) and Southern annular mode propagation ($\sim 150$ days). These dynamical metrics serve as an initial benchmarking tool to inform AI model development and understand their limitations, which may be essential for out-of-distribution applications (e.g., extrapolating to unseen climates).
- North America > United States > Illinois > Cook County > Chicago (0.04)
- North America > United States > Colorado > Boulder County > Boulder (0.04)
- Europe > United Kingdom > England > Cambridgeshire > Cambridge (0.04)
- (2 more...)
Balloon-equipped 'wearable robot' could help stroke survivors
Breakthroughs, discoveries, and DIY tips sent every weekday. A first-of-its-kind, soft, vest-like wearable designed by Harvard researchers could help stroke survivors and people living with ALS regain crucial upper limb movement. The researchers call the device a "wearable robot," which uses inflatable balloons positioned under a patient's arm that bulge and contract based on the desired movement. A combination of machine learning software and a separate physics-based model helps the robot interpret the patient's intended movements and personalize actions accordingly. In testing, the robot was able to correctly identify the user's intended shoulder movement 94.2 percent of the time.
- Health & Medicine > Therapeutic Area > Neurology (0.61)
- Health & Medicine > Therapeutic Area > Hematology (0.61)
- Health & Medicine > Therapeutic Area > Cardiology/Vascular Diseases (0.61)
Integrating Physics-Based and Data-Driven Approaches for Probabilistic Building Energy Modeling
Von Krannichfeldt, Leandro, Orehounig, Kristina, Fink, Olga
Building energy modeling is a key tool for optimizing the performance of building energy systems. Historically, a wide spectrum of methods has been explored -- ranging from conventional physics-based models to purely data-driven techniques. Recently, hybrid approaches that combine the strengths of both paradigms have gained attention. These include strategies such as learning surrogates for physics-based models, modeling residuals between simulated and observed data, fine-tuning surrogates with real-world measurements, using physics-based outputs as additional inputs for data-driven models, and integrating the physics-based output into the loss function the data-driven model. Despite this progress, two significant research gaps remain. First, most hybrid methods focus on deterministic modeling, often neglecting the inherent uncertainties caused by factors like weather fluctuations and occupant behavior. Second, there has been little systematic comparison within a probabilistic modeling framework. This study addresses these gaps by evaluating five representative hybrid approaches for probabilistic building energy modeling, focusing on quantile predictions of building thermodynamics in a real-world case study. Our results highlight two main findings. First, the performance of hybrid approaches varies across different building room types, but residual learning with a Feedforward Neural Network performs best on average. Notably, the residual approach is the only model that produces physically intuitive predictions when applied to out-of-distribution test data. Second, Quantile Conformal Prediction is an effective procedure for calibrating quantile predictions in case of indoor temperature modeling.
- Europe > Austria > Vienna (0.04)
- North America > United States > New York > New York County > New York City (0.04)
- Europe > Switzerland > Vaud > Lausanne (0.04)
- Asia > Japan > Honshū > Kansai > Osaka Prefecture > Osaka (0.04)
Adversarial Disentanglement by Backpropagation with Physics-Informed Variational Autoencoder
Koune, Ioannis Christoforos, Cicirello, Alice
Inference and prediction under partial knowledge of a physical system is challenging, particularly when multiple confounding sources influence the measured response. Explicitly accounting for these influences in physics-based models is often infeasible due to epistemic uncertainty, cost, or time constraints, resulting in models that fail to accurately describe the behavior of the system. On the other hand, data-driven machine learning models such as variational autoencoders are not guaranteed to identify a parsimonious representation. As a result, they can suffer from poor generalization performance and reconstruction accuracy in the regime of limited and noisy data. We propose a physics-informed variational autoencoder architecture that combines the interpretability of physics-based models with the flexibility of data-driven models. To promote disentanglement of the known physics and confounding influences, the latent space is partitioned into physically meaningful variables that parametrize a physics-based model, and data-driven variables that capture variability in the domain and class of the physical system. The encoder is coupled with a decoder that integrates physics-based and data-driven components, and constrained by an adversarial training objective that prevents the data-driven components from overriding the known physics, ensuring that the physics-grounded latent variables remain interpretable. We demonstrate that the model is able to disentangle features of the input signal and separate the known physics from confounding influences using supervision in the form of class and domain observables. The model is evaluated on a series of synthetic case studies relevant to engineering structures, demonstrating the feasibility of the proposed approach.
- North America > United States (0.04)
- Europe > Netherlands > South Holland > Delft (0.04)
- Europe > United Kingdom > England > Cambridgeshire > Cambridge (0.04)
- (2 more...)