Energy
A Physics-Informed Neural Network Approach for UAV Path Planning in Dynamic Environments
Unmanned aerial vehicles (UAVs) operating in dynamic wind fields must generate safe and energy-efficient trajectories under physical and environmental constraints. Traditional planners, such as A* and kinodynamic RRT*, often yield suboptimal or non-smooth paths due to discretization and sampling limitations. This paper presents a physics-informed neural network (PINN) framework that embeds UAV dynamics, wind disturbances, and obstacle avoidance directly into the learning process. Without requiring supervised data, the PINN learns dynamically feasible and collision-free trajectories by minimizing physical residuals and risk-aware objectives. Comparative simulations show that the proposed method outperforms A* and Kino-RRT* in control energy, smoothness, and safety margin, while maintaining similar flight efficiency. The results highlight the potential of physics-informed learning to unify model-based and data-driven planning, providing a scalable and physically consistent framework for UAV trajectory optimization.
Towards Interpretable Deep Learning and Analysis of Dynamical Systems via the Discrete Empirical Interpolation Method
We present a differentiable framework that leverages the Discrete Empirical Interpolation Method (DEIM) for interpretable deep learning and dynamical system analysis. Although DEIM efficiently approximates nonlinear terms in projection-based reduced-order models (POD-ROM), its fixed interpolation points limit the adaptability to complex and time-varying dynamics. To address this limitation, we first develop a differentiable adaptive DEIM formulation for the one-dimensional viscous Burgers equation, which allows neural networks to dynamically select interpolation points in a computationally efficient and physically consistent manner. We then apply DEIM as an interpretable analysis tool for examining the learned dynamics of a pre-trained Neural Ordinary Differential Equation (NODE) on a two-dimensional vortex-merging problem. The DEIM trajectories reveal physically meaningful features in the learned dynamics of NODE and expose its limitations when extrapolating to unseen flow configurations. These findings demonstrate that DEIM can serve not only as a model reduction tool but also as a diagnostic framework for understanding and improving the generalization behavior of neural differential equation models.
Using Non-Expert Data to Robustify Imitation Learning via Offline Reinforcement Learning
Huang, Kevin, Scalise, Rosario, Winston, Cleah, Agrawal, Ayush, Zhang, Yunchu, Baijal, Rohan, Grotz, Markus, Boots, Byron, Burchfiel, Benjamin, Itkina, Masha, Shah, Paarth, Gupta, Abhishek
Imitation learning has proven effective for training robots to perform complex tasks from expert human demonstrations. However, it remains limited by its reliance on high-quality, task-specific data, restricting adaptability to the diverse range of real-world object configurations and scenarios. In contrast, non-expert data -- such as play data, suboptimal demonstrations, partial task completions, or rollouts from suboptimal policies -- can offer broader coverage and lower collection costs. However, conventional imitation learning approaches fail to utilize this data effectively. To address these challenges, we posit that with right design decisions, offline reinforcement learning can be used as a tool to harness non-expert data to enhance the performance of imitation learning policies. We show that while standard offline RL approaches can be ineffective at actually leveraging non-expert data under the sparse data coverage settings typically encountered in the real world, simple algorithmic modifications can allow for the utilization of this data, without significant additional assumptions. Our approach shows that broadening the support of the policy distribution can allow imitation algorithms augmented by offline RL to solve tasks robustly, showing considerably enhanced recovery and generalization behavior. In manipulation tasks, these innovations significantly increase the range of initial conditions where learned policies are successful when non-expert data is incorporated. Moreover, we show that these methods are able to leverage all collected data, including partial or suboptimal demonstrations, to bolster task-directed policy performance. This underscores the importance of algorithmic techniques for using non-expert data for robust policy learning in robotics. Website: https://uwrobotlearning.github.io/RISE-offline/
BUILDA: A Thermal Building Data Generation Framework for Transfer Learning
Krug, Thomas, Raisch, Fabian, Aimer, Dominik, Wirnsberger, Markus, Sigg, Ferdinand, Schรคfer, Benjamin, Tischler, Benjamin
Transfer learning (TL) can improve data-driven modeling of building thermal dynamics. Therefore, many new TL research areas emerge in the field, such as selecting the right source model for TL. However, these research directions require massive amounts of thermal building data which is lacking presently. Neither public datasets nor existing data generators meet the needs of TL research in terms of data quality and quantity. Moreover, existing data generation approaches typically require expert knowledge in building simulation. We present BuilDa, a thermal building data generation framework for producing synthetic data of adequate quality and quantity for TL research. The framework does not require profound building simulation knowledge to generate large volumes of data. BuilDa uses a single-zone Modelica model that is exported as a Functional Mock-up Unit (FMU) and simulated in Python. We demonstrate BuilDa by generating data and utilizing it for pretraining and fine-tuning TL models.
Cultivating Pluralism In Algorithmic Monoculture: The Community Alignment Dataset
Zhang, Lily Hong, Milli, Smitha, Jusko, Karen, Smith, Jonathan, Amos, Brandon, Bouaziz, Wassim, Revel, Manon, Kussman, Jack, Sheynin, Yasha, Titus, Lisa, Radharapu, Bhaktipriya, Yu, Jane, Sarma, Vidya, Rose, Kris, Nickel, Maximilian
How can large language models (LLMs) serve users with varying preferences that may conflict across cultural, political, or other dimensions? To advance this challenge, this paper establishes four key results. First, we demonstrate, through a large-scale multilingual human study with representative samples from five countries (N=15,000), that humans exhibit significantly more variation in preferences than the responses of 21 state-of-the-art LLMs. Second, we show that existing methods for preference dataset collection are insufficient for learning the diversity of human preferences even along two of the most salient dimensions of variability in global values, due to the underlying homogeneity of candidate responses. Third, we argue that this motivates the need for negatively-correlated sampling when generating candidate sets, and we show that simple prompt-based techniques for doing so significantly enhance the performance of alignment methods in learning heterogeneous preferences. Fourth, based on this novel candidate sampling approach, we collect and open-source Community Alignment, the largest and most representative multilingual and multi-turn preference dataset to date, featuring almost 200,000 comparisons from annotators spanning five countries. We hope that the Community Alignment dataset will be a valuable resource for improving the effectiveness of LLMs for a diverse global population.
US Dept of Energy partners with AMD to build two supercomputers: Report
The United States has formed a $1bn partnership with Advanced Micro Devices (AMD) to construct two supercomputers that will tackle large scientific problems ranging from nuclear power to cancer treatments to national security. The Reuters news agency first reported the new partnership, citing Energy Secretary Chris Wright and AMD CEO Lisa Su. The machines can accelerate the process of making scientific discoveries in areas the US is focused on. Energy Secretary Wright said the systems would "supercharge" advances in nuclear power and fusion energy, technologies for defence and national security, and the development of drugs. Scientists and companies are trying to replicate fusion, the reaction that fuels the sun, by jamming light atoms in a plasma gas under intense heat and pressure to release massive amounts of energy.
Baseus Security S2 Outdoor Camera 4K review: It sees the light
When you purchase through links in our articles, we may earn a small commission. A solar panel on a security cam is nothing new, but the panel on this one tracks the sun, rotating to gain maximum exposure. If you can mount it where it can harvest a steady supply of sunlight, the Baseus Security S2 Outdoor Camera 4K's tracking solar panel makes it one of the few outdoor cameras that can run truly unattended, capturing crisp 4K-resolution video as a bonus. For many households, outdoor cameras are the front line of home security. The devices watch over driveways, porches, and backyards, catching activity that doorbell cameras often miss.
The great wildebeest migration, seen from space: satellites and AI are helping count Africa's wildlife
The great wildebeest migration, seen from space: satellites and AI are helping count Africa's wildlife The Great Wildebeest Migration is one of the most remarkable natural spectacles on Earth. Each year, immense herds of wildebeest, joined by zebras and gazelles, travel 800-1,000km between Tanzania and Kenya in search of fresh grazing after the rains . This vast, circular journey is the engine of the Serengeti-Mara ecosystem. The migration feeds predators such as lions and crocodiles, fertilises the land and sustains the grasslands. Countless other species, and human livelihoods tied to rangelands and tourism, depend on it.
Inside the Data Centers That Train A.I. and Drain the Electrical Grid
A data center, which can use as much electricity as Philadelphia, is the new American factory, creating the future and propping up the economy. "I do guess that a lot of the world gets covered in data centers," Sam Altman, the C.E.O. of OpenAI, has said. Drive in almost any direction from almost any American city, and soon enough you'll arrive at a data center--a giant white box rising from graded earth, flanked by generators and fenced like a prison yard. Data centers for artificial intelligence are the new American factory. Packed with computing equipment, they absorb information and emit A.I. Since the launch of ChatGPT, in 2022, they have begun to multiply at an astonishing rate. "I do guess that a lot of the world gets covered in data centers over time," Sam Altman, the C.E.O. of OpenAI, recently said. The leading independent operator of A.I. data centers in the United States is CoreWeave, which was founded eight years ago, as a casual experiment. In 2017, traders at a middling New York hedge fund decided to begin mining cryptocurrency, which they used as the entry fee for their fantasy-football league. To mine the crypto, they bought a graphics-processing unit, a powerful microchip made by the company Nvidia. The G.P.U. was marketed to video gamers, but Nvidia offered software that turned it into a low-budget supercomputer. "It was so successful, from a return-of-capital perspective, that we started scaling it," Brian Venturo, one of CoreWeave's co-founders, told me. "If you make your money back in, like, five days, you want to do that a lot." Within a year, the traders had quit the hedge-fund business and bought several thousand G.P.U.s, which they ran from Venturo's grandfather's garage, in New Jersey.
In Russia's 'blitz' of Ukraine, the question of appeasement is back
In Russia's'blitz' of Ukraine, the question of appeasement is back Following another week of intensive and lethal Russian bombardment of Ukraine's cities, a composite image has been doing the rounds on Ukrainian social media. Underneath an old, black-and-white photo of Londoners queuing at a fruit and vegetable stall surrounded by the bombed-out rubble of the Blitz, a second image - this time in colour - creates a striking juxtaposition. Taken on Saturday, it shows shoppers thronging to similar stalls in a northern suburb of the Ukrainian capital, Kyiv, while a column of black smoke rises ominously in the background. Bombs can't stop markets, reads the caption linking the two images. The night before, as the city's sleep was interrupted once again by the now all-too-familiar booms of missile and drone strikes, two people were killed and nine others injured.