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Ditch the antibacterial soap this cold and flu season

Popular Science

You still need to wash your hands with soap and warm water though. Breakthroughs, discoveries, and DIY tips sent every weekday. The most dreaded time of year rolls around every winter like clockwork: cold and flu season. The time when hand washing increases, sanitizing surfaces intensifies, and old and young schedule regular seasonal vaccines in an attempt to prevent sickness from descending on their households. But there's one piece of ammunition you should absolutely skip this season--and all year-round--because it does more harm than good: antibacterial hand soap.


Multimodal signal fusion for stress detection using deep neural networks: a novel approach for converting 1D signals to unified 2D images

Hasanpoor, Yasin, Tarvirdizadeh, Bahram, Alipour, Khalil, Ghamari, Mohammad

arXiv.org Artificial Intelligence

This study introduces a novel method that transforms multimodal physiological signals -- photoplethysmography (PPG), galvanic skin response (GSR), and acceleration (ACC) -- into 2D image matrices to enhance stress detection using convolutional neural networks (CNNs). Unlike traditional approaches that process these signals separately or rely on fixed encodings, our technique fuses them into structured image representations that enable CNNs to capture temporal and cross - signal dependencies more effectively. This image - based transformation not only improves interpretability but also serves as a rob ust form of data augmentation. To further enhance generalization and model robustness, we systematically reorganize the fused signals into multiple formats, combining them in a multi - stage training pipeline. This approach significantly boost s classification performance, with test accuracy improving from 92.57% (using individual signal orderings) to 95.86% when using the combined strategy. While demonstrated here in the context of stress detection, the proposed method is broadly applicable to any domain invo lving multimodal physiological signals, paving the way for more accurate, personalized, and real time health monitoring through wearable technologies.


A MILP-Based Solution to Multi-Agent Motion Planning and Collision Avoidance in Constrained Environments

Jaitly, Akshay, Cline, Jack, Farzan, Siavash

arXiv.org Artificial Intelligence

We propose a mixed-integer linear program (MILP) for multi-agent motion planning that embeds Polytopic Action-based Motion Planning (PAAMP) into a sequence-then-solve pipeline. Region sequences confine each agent to adjacent convex polytopes, while a big-M hyperplane model enforces inter-agent separation. Collision constraints are applied only to agents sharing or neighboring a region, which reduces binary variables exponentially compared with naive formulations. An L1 path-length-plus-acceleration cost yields smooth trajectories. We prove finite-time convergence and demonstrate on representative multi-agent scenarios with obstacles that our formulation produces collision-free trajectories an order of magnitude faster than an unstructured MILP baseline.


Data Transformation Strategies to Remove Heterogeneity

Yoo, Sangbong, Lee, Jaeyoung, Yoon, Chanyoung, Son, Geonyeong, Hong, Hyein, Seo, Seongbum, Yim, Soobin, Jung, Chanyoung, Park, Jungsoo, Kim, Misuk, Jang, Yun

arXiv.org Artificial Intelligence

Data heterogeneity is a prevalent issue, stemming from various conflicting factors, making its utilization complex. This uncertainty, particularly resulting from disparities in data formats, frequently necessitates the involvement of experts to find resolutions. Current methodologies primarily address conflicts related to data structures and schemas, often overlooking the pivotal role played by data transformation. As the utilization of artificial intelligence (AI) continues to expand, there is a growing demand for a more streamlined data preparation process, and data transformation becomes paramount. It customizes training data to enhance AI learning efficiency and adapts input formats to suit diverse AI models. Selecting an appropriate transformation technique is paramount in preserving crucial data details. Despite the widespread integration of AI across various industries, comprehensive reviews concerning contemporary data transformation approaches are scarce. This survey explores the intricacies of data heterogeneity and its underlying sources. It systematically categorizes and presents strategies to address heterogeneity stemming from differences in data formats, shedding light on the inherent challenges associated with each strategy.


A Data-Based Architecture for Flight Test without Test Points

Harp, D. Isaiah, Ott, Joshua, Alora, John, Asmar, Dylan

arXiv.org Artificial Intelligence

The justification for the "test point" derives from the test pilot's obligation to reproduce faithfully the pre-specified conditions of some model prediction. Pilot deviation from those conditions invalidates the model assumptions. Flight test aids have been proposed to increase accuracy on more challenging test points. However, the very existence of databands and tolerances is the problem more fundamental than inadequate pilot skill. We propose a novel approach, which eliminates test points. We start with a high-fidelity digital model of an air vehicle. Instead of using this model to generate a point prediction, we use a machine learning method to produce a reduced-order model (ROM). The ROM has two important properties. First, it can generate a prediction based on any set of conditions the pilot flies. Second, if the test result at those conditions differ from the prediction, the ROM can be updated using the new data. The outcome of flight test is thus a refined ROM at whatever conditions were flown. This ROM in turn updates and validates the high-fidelity model. We present a single example of this "point-less" architecture, using T-38C flight test data. We first use a generic aircraft model to build a ROM of longitudinal pitching motion as a hypersurface. We then ingest unconstrained flight test data and use Gaussian Process Regression to update and condition the hypersurface. By proposing a second-order equivalent system for the T-38C, this hypersurface then generates parameters necessary to assess MIL-STD-1797B compliance for longitudinal dynamics.


GeAR: Generation Augmented Retrieval

Liu, Haoyu, Huang, Shaohan, Liu, Jianfeng, Zhan, Yuefeng, Sun, Hao, Deng, Weiwei, Sun, Feng, Wei, Furu, Zhang, Qi

arXiv.org Artificial Intelligence

Document retrieval techniques form the foundation for the development of large-scale information systems. The prevailing methodology is to construct a bi-encoder and compute the semantic similarity. However, such scalar similarity is difficult to reflect enough information and impedes our comprehension of the retrieval results. In addition, this computational process mainly emphasizes the global semantics and ignores the fine-grained semantic relationship between the query and the complex text in the document. In this paper, we propose a new method called $\textbf{Ge}$neration $\textbf{A}$ugmented $\textbf{R}$etrieval ($\textbf{GeAR}$) that incorporates well-designed fusion and decoding modules. This enables GeAR to generate the relevant text from documents based on the fused representation of the query and the document, thus learning to "focus on" the fine-grained information. Also when used as a retriever, GeAR does not add any computational burden over bi-encoders. To support the training of the new framework, we have introduced a pipeline to efficiently synthesize high-quality data by utilizing large language models. GeAR exhibits competitive retrieval and localization performance across diverse scenarios and datasets. Moreover, the qualitative analysis and the results generated by GeAR provide novel insights into the interpretation of retrieval results. The code, data, and models will be released after completing technical review to facilitate future research.


Physics-informed Gaussian Processes for Safe Envelope Expansion

Harp, D. Isaiah, Ott, Joshua, Asmar, Dylan M., Alora, John, Kochenderfer, Mykel J.

arXiv.org Artificial Intelligence

Flight test analysis often requires predefined test points with arbitrarily tight tolerances, leading to extensive and resource-intensive experimental campaigns. To address this challenge, we propose a novel approach to flight test analysis using Gaussian processes (GPs) with physics-informed mean functions to estimate aerodynamic quantities from arbitrary flight test data, validated using real T-38 aircraft data collected in collaboration with the United States Air Force Test Pilot School. We demonstrate our method by estimating the pitching moment coefficient without requiring predefined or repeated flight test points, significantly reducing the need for extensive experimental campaigns. Our approach incorporates aerodynamic models as priors within the GP framework, enhancing predictive accuracy across diverse flight conditions and providing robust uncertainty quantification. Key contributions include the integration of physics-based priors in a probabilistic model, which allows for precise computation from arbitrary flight test maneuvers, and the demonstration of our method capturing relevant dynamic characteristics such as short-period mode behavior. The proposed framework offers a scalable and generalizable solution for efficient data-driven flight test analysis and is able to accurately predict the short period frequency and damping for the T-38 across several Mach and dynamic pressure profiles.


WavePulse: Real-time Content Analytics of Radio Livestreams

Mittal, Govind, Gupta, Sarthak, Wagle, Shruti, Chopra, Chirag, DeMattee, Anthony J, Memon, Nasir, Ahamad, Mustaque, Hegde, Chinmay

arXiv.org Artificial Intelligence

Radio remains a pervasive medium for mass information dissemination, with AM/FM stations reaching more Americans than either smartphone-based social networking or live television. Increasingly, radio broadcasts are also streamed online and accessed over the Internet. We present WavePulse, a framework that records, documents, and analyzes radio content in real-time. While our framework is generally applicable, we showcase the efficacy of WavePulse in a collaborative project with a team of political scientists focusing on the 2024 Presidential Elections. We use WavePulse to monitor livestreams of 396 news radio stations over a period of three months, processing close to 500,000 hours of audio streams. These streams were converted into time-stamped, diarized transcripts and analyzed to track answer key political science questions at both the national and state levels. Our analysis revealed how local issues interacted with national trends, providing insights into information flow. Our results demonstrate WavePulse's efficacy in capturing and analyzing content from radio livestreams sourced from the Web. Code and dataset can be accessed at \url{https://wave-pulse.io}.


Dynamics Modeling using Visual Terrain Features for High-Speed Autonomous Off-Road Driving

Gibson, Jason, Alavilli, Anoushka, Tevere, Erica, Theodorou, Evangelos A., Spieler, Patrick

arXiv.org Artificial Intelligence

Rapid autonomous traversal of unstructured terrain is essential for scenarios such as disaster response, search and rescue, or planetary exploration. As a vehicle navigates at the limit of its capabilities over extreme terrain, its dynamics can change suddenly and dramatically. For example, high-speed and varying terrain can affect parameters such as traction, tire slip, and rolling resistance. To achieve effective planning in such environments, it is crucial to have a dynamics model that can accurately anticipate these conditions. In this work, we present a hybrid model that predicts the changing dynamics induced by the terrain as a function of visual inputs. We leverage a pre-trained visual foundation model (VFM) DINOv2, which provides rich features that encode fine-grained semantic information. To use this dynamics model for planning, we propose an end-to-end training architecture for a projection distance independent feature encoder that compresses the information from the VFM, enabling the creation of a lightweight map of the environment at runtime. We validate our architecture on an extensive dataset (hundreds of kilometers of aggressive off-road driving) collected across multiple locations as part of the DARPA Robotic Autonomy in Complex Environments with Resiliency (RACER) program. https://www.youtube.com/watch?v=dycTXxEosMk


Rare bees kill Meta's nuclear-powered AI data center plans

Popular Science

Environmental regulators reportedly quashed Mark Zuckerberg's nuclear plant partnership meant to help power Meta's ongoing artificial intelligence projects. Details remain scarce, but the main reason for pausing plans allegedly comes down to one issue--rare bees. The tech company's setback, first reported on November 4th by Financial Times, came after surveyors discovered the currently unspecified pollinators while reviewing land meant for a new AI data center. The selected area offered easy access to tap into the nearby, unspecified nuclear plant. Zuckerberg, however, confirmed the project's cancellation during a Meta all-hands meeting last week, according to FT.