Energy
Km-scale dynamical downscaling through conformalized latent diffusion models
Brusaferri, Alessandro, Ballarino, Andrea
Abstract--Dynamical downscaling is crucial for deriving high-resolution meteorological fields from coarse-scale simulations, enabling detailed analysis for critical applications such as weather forecasting and renewable energy modeling. Generative Diffusion models (DMs) have recently emerged as powerful data-driven tools for this task, offering reconstruction fidelity and more scalable sampling supporting uncertainty quantification. In this work, we tackle this issue by augmenting the downscaling pipeline with a conformal prediction framework. Specifically, the DM's samples are post-processed to derive conditional quantile estimates, incorporated into a conformalized quantile regression procedure targeting locally adaptive prediction intervals with finite-sample marginal validity. The proposed approach is evaluated on ERA5 reanalysis data over Italy, downscaled to a 2-km grid. Results demonstrate grid-point-level uncertainty estimates with markedly improved coverage and stable probabilistic scores relative to the DM baseline, highlighting the potential of con-formalized generative models for more trustworthy probabilistic downscaling to high-resolution meteorological fields.
Safe Driving in Occluded Environments
Wang, Zhuoyuan, Jia, Tongyao, Rajborirug, Pharuj, Ramesh, Neeraj, Okuda, Hiroyuki, Suzuki, Tatsuya, Kar, Soummya, Nakahira, Yorie
Abstract--Ensuring safe autonomous driving in the presence of occlusions poses a significant challenge in its policy design. While existing model-driven control techniques based on set invariance can handle visible risks, occlusions create latent risks in which safety-critical states are not observable. Data-driven techniques also struggle to handle latent risks because direct mappings from risk-critical objects in sensor inputs to safe actions cannot be learned without visible risk-critical objects. Motivated by these challenges, in this paper, we propose a probabilistic safety certificate for latent risk. Our key technical enabler is the application of probabilistic invariance: It relaxes the strict observability requirements imposed by set-invariance methods that demand the knowledge of risk-critical states. The proposed techniques provide linear action constraints that confine the latent risk probability within tolerance. Such constraints can be integrated into model predictive controllers or embedded in data-driven policies to mitigate latent risks. The proposed method is tested using the CARLA simulator and compared with a few existing techniques. The theoretical and empirical analysis jointly demonstrate that the proposed methods assure long-term safety in real-time control in occluded environments without being overly conservative and with transparency to exposed risks. ISUAL occlusions impose significant challenges in the policy design of autonomous driving.
Toward Reasoning-Centric Time-Series Analysis
Wang, Xinlei, Tan, Mingtian, Qiu, Jing, Zhao, Junhua, Gu, Jinjin
Abstract--T raditional time series analysis has long relied on pattern recognition, trained on static and well-established benchmarks. However, in real-world settings - where policies shift, human behavior adapts, and unexpected events unfold - effective analysis must go beyond surface-level trends to uncover the actual forces driving them. The recent rise of Large Language Models (LLMs) presents new opportunities for rethinking time series analysis by integrating multimodal inputs. However, as the use of LLMs becomes popular, we must remain cautious, asking why we use LLMs and how to exploit them effectively . Most existing LLM-based methods still employ their numerical regression ability and ignore their deeper reasoning potential. This paper argues for rethinking time series with LLMs as a reasoning task that prioritizes causal structure and explainability . This shift brings time series analysis closer to human-aligned understanding, enabling transparent and context-aware insights in complex real-world environments. Time series analysis has traditionally been framed as a pattern recognition problem, extracting trends and correlations from observed data.
Geometric Model Predictive Path Integral for Agile UAV Control with Online Collision Avoidance
Pochobradský, Pavel, Procházka, Ondřej, Pěnička, Robert, Vonásek, Vojtěch, Saska, Martin
In this letter, we introduce Geometric Model Predictive Path Integral (GMPPI), a sampling-based controller capable of tracking agile trajectories while avoiding obstacles. In each iteration, GMPPI generates a large number of candidate rollout trajectories and then averages them to create a nominal control to be followed by the Unmanned Aerial Vehicle (UAV). We propose using geometric SE(3) control to generate part of the rollout trajectories, significantly increasing precision in agile flight. Furthermore, we introduce varying rollout simulation time step length and dynamic cost and noise parameters, vastly improving tracking performance of smooth and low-speed trajectories over an existing Model Predictive Path Integral (MPPI) implementation. Finally, we propose an integration of GMPPI with a stereo depth camera, enabling online obstacle avoidance at high speeds, a crucial step towards autonomous UAV flights in complex environments. The proposed controller can track simulated agile reference trajectories with position error similar to the geometric SE(3) controller. However, the same configuration of the proposed controller can avoid obstacles in a simulated forest environment at speeds of up to 13m/s, surpassing the performance of a state-of-the-art obstacle-aware planner. In real-world experiments, GMPPI retains the capability to track agile trajectories and avoids obstacles at speeds of up to 10m/s.
InferA: A Smart Assistant for Cosmological Ensemble Data
Tam, Justin Z., Grosset, Pascal, Banesh, Divya, Ramachandra, Nesar, Turton, Terece L., Ahrens, James
Analyzing large-scale scientific datasets presents substantial challenges due to their sheer volume, structural complexity, and the need for specialized domain knowledge. Automation tools, such as PandasAI, typically require full data ingestion and lack context of the full data structure, making them impractical as intelligent data analysis assistants for datasets at the terabyte scale. To overcome these limitations, we propose InferA, a multi-agent system that leverages large language models to enable scalable and efficient scientific data analysis. At the core of the architecture is a supervisor agent that orchestrates a team of specialized agents responsible for distinct phases of the data retrieval and analysis. The system engages interactively with users to elicit their analytical intent and confirm query objectives, ensuring alignment between user goals and system actions. To demonstrate the framework's usability, we evaluate the system using ensemble runs from the HACC cosmology simulation which comprises several terabytes.
Lifting Manifolds to Mitigate Pseudo-Alignment in LLM4TS
Zheng, Liangwei Nathan, Liang, Wenhao, Zhang, Wei Emma, Xu, Miao, Maennel, Olaf, Chen, Weitong
Pseudo-Alignment is a pervasive challenge in many large language models for time series (LLM4TS) models, often causing them to underperform compared to linear models or randomly initialised backbones. However, there is limited discussion in the community for the reasons that pseudo-alignment occurs. In this work, we conduct a thorough investigation into the root causes of pseudo-alignment in LLM4TS and build a connection of pseudo-alignment to the cone effect in LLM. We demonstrate that pseudo-alignment arises from the interplay of cone effect within pretrained LLM components and the intrinsically low-dimensional manifold of time-series data. In addition, we also introduce \textit{\textbf{TimeSUP}}, a novel technique designed to mitigate this issue and improve forecast performance in existing LLM4TS approaches. TimeSUP addresses this by increasing the time series manifold to more closely match the intrinsic dimension of language embeddings, allowing the model to distinguish temporal signals clearly while still capturing shared structures across modalities. As a result, representations for time and language tokens remain distinct yet exhibit high cosine similarity, signifying that the model preserves each modality unique features while learning their commonalities in a unified embedding space. Empirically, TimeSUP consistently outperforms state-of-the-art LLM4TS methods and other lightweight baselines on long-term forecasting performance. Furthermore, it can be seamlessly integrated into four existing LLM4TS pipelines and delivers significant improvements in forecasting performance.
Coherent Load Profile Synthesis with Conditional Diffusion for LV Distribution Network Scenario Generation
Brash, Alistair, Lu, Junyi, Stephen, Bruce, Brown, Blair, Atkinson, Robert, Michie, Craig, MacIntyre, Fraser, Tachtatzis, Christos
Limited visibility of power distribution network power flows at the low voltage level presents challenges to both distribution network operators from a planning perspective and distribution system operators from a congestion management perspective. Forestalling these challenges through scenario analysis is confounded by the lack of realistic and coherent load data across representative distribution feeders. Load profiling approaches often rely on summarising demand through typical profiles, which oversimplifies the complexity of substation-level operations and limits their applicability in specific power system studies. Sampling methods, and more recently generative models, have attempted to address this through synthesising representative loads from historical exemplars; however, while these approaches can approximate load shapes to a convincing degree of fidelity, the co-behaviour between substations, which ultimately impacts higher voltage level network operation, is often overlooked. This limitation will become even more pronounced with the increasing integration of low-carbon technologies, as estimates of base loads fail to capture load diversity. To address this gap, a Conditional Diffusion model for synthesising daily active and reactive power profiles at the low voltage distribution substation level is proposed. The evaluation of fidelity is demonstrated through conventional metrics capturing temporal and statistical realism, as well as power flow modelling. The results show synthesised load profiles are plausible both independently and as a cohort in a wider power systems context. The Conditional Diffusion model is benchmarked against both naive and state-of-the-art models to demonstrate its effectiveness in producing realistic scenarios on which to base sub-regional power distribution network planning and operations.
Large Language Models Inference Engines based on Spiking Neural Networks
Balaji, Adarsha, Madireddy, Sandeep, Balaprakash, Prasanna
Foundational models based on the transformer architecture are currently the state-of-the-art in general language modeling, as well as in scientific areas such as material science and climate. However, training and deploying these models is computationally challenging as the time and space complexity has a quadratic relation to the input sequence length. Several efforts exploring efficient computational paradigms and model architectures to address these limitations have been made. In this work, we explore spiking neural networks (SNNs) to design transformer models. A challenge in training large-scale SNNs, using existing surrogate learning methods is inefficient and time-consuming. On the other hand, techniques to convert existing transformer-based models to their SNN equivalent are not scalable, as achieving optimal performance comes at the cost of a large number of spike time-steps, i.e. increased latency. To address this, we propose NeurTransformer, a methodology for designing transformer-based SNN for inference using a supervised fine-tuning approach with existing conversion methods. The proposed methodology works by: (1) replacing the self-attention mechanism with a spike-based self-attention (SSA), (2) converting the feed-forward block of the trained transformer model to its equivalent SNN, and (3) fine-tuning the SSA block using SNN-based surrogate learning algorithms. We benchmark the proposed methodology and demonstrate its accuracy and scalability using three variants of the GPT-2 model of increasing model size. We observe that the converted GPT-2 small models demonstrate a 5-12% loss in cosine similarity and a 9.7% reduction in perplexity. Finally, we demonstrate the energy efficiency of the SSA block compared to the ASA block and show between 64.71% and 85.28% reductions in estimated energy consumption when implementing the self-attention mechanism on a digital hardware.
Astonishing interactive map lays bare where MILLIONS of homes will be submerged by water within a few years... are YOU at risk?
Doctor's husband'was watching X-rated videos in his house while daughter, 2, died in roasting car outside' Florida's housing market is flashing a warning for the rest of the US Now scientists redefine'obese' - and they've made up to 60% more people'fat' Bella Hadid's health battle takes dark turn: Loved ones reveal hellish new details about'missing' model... as ominous texts emerge America's saddest lost soul can no longer SPEAK and spends days hitting herself'after years of unspeakable abuse by gangs of men' Shocking moment brazen gunman opens fire at Michigan businessman's Land Rover in daylight attack'You will DIE if you do not remove your breasts', doctors screamed at me. I refused and tried a new experimental therapy instead... now I'm cancer-free The world's most powerful passport revealed - as UK and USA both drop to record lows Police say they have FOUND woman seen in viral'kidnapping' video and reveal what happened to her after harrowing footage emerged Will Trump's Gaza peace deal fail? Policy expert MARK DUBOWITZ breaks down all the forces at play... and how the president can actually pull this off America's most renowned'prophet' makes startling prediction about alien'mothership' Kim Kardashian says she wasn't'emotionally or financially safe' during'toxic' marriage to Kanye West as she claims rapper hasn't contacted their children for MONTHS and has destroyed her dating life Astonishing interactive map lays bare where MILLIONS of homes will be submerged by water within a few years... are YOU at risk? Outrageous reason LA County CEO was awarded $2m payout for'hurt feelings' that'll see her take months off taxpayer-funded $570,000-a-year job Ugly divorce war between Mitt Romney's wealthy brother and estranged wife before she was found dead Full horrors of torture suffered by Noa Argamani's commando boyfriend are revealed - including how 6ft 5in hostage was beaten and kept chained in 6ft cell for a year after he tried to escape from Hamas Mother, 52, and daughter, 21, die after eating'poisoned birthday cake delivered by relative who owed them money' in Brazil Astonishing interactive map lays bare where MILLIONS of homes will be submerged by water within a few years... are YOU at risk? Millions of buildings and even more Americans could be at risk of sinking underwater by the end of the century. Researchers from McGill University in Canada warned rising sea levels, resulting from continued greenhouse gas emissions, threaten to wipe out coastal cities worldwide. Sea level rise measures the ocean's surface height over time.
The Download: Big Tech's carbon removals plans, and the next wave of nuclear reactors
Microsoft, JP MorganChase, and a tech company consortium that includes Alphabet, Meta, Shopify, and Stripe have all recently struck multimillion-dollar deals to pay paper mill owners to capture at least hundreds of thousands of tons of this greenhouse gas by installing carbon scrubbing equipment in their facilities. The captured carbon dioxide will then be piped down into saline aquifers more than a mile underground, where it should be sequestered permanently. Big Tech is suddenly betting big on this form of carbon removal, known as bioenergy with carbon capture and storage, or BECCS. But experts have raised a number of concerns. Like many new nuclear startups, Kairos promises a path to reliable, 24/7 decarbonized power. Unlike most, it already has prototypes under construction and permits for several reactors.