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Weather researchers unleash fleet of drones that sail directly into eye of hurricane

FOX News

Pawleys Island, South Carolina, Mayor Brian Henry tells "Your World" that Hurricane Ian was different and brought a significant storm surge to the island. A high-tech sailing drone was deployed onto the Atlantic Ocean near Charleston, South Carolina, this past weekend to collect weather data directly from wicked hurricanes. The autonomous ocean drone, known as a saildrone, was redeployed by California-based company Saildrone Inc., which designs and operates autonomous ocean drones, in partnership with the National Oceanic and Atmospheric Administration (NOAA) to assist the agency in data collection on hurricanes. The same saildrone made international headlines in 2021 when it captured the "first-ever video from inside a major hurricane at sea" when Hurricane Sam barreled across the Atlantic. NOAA has previously incorporated drones into its research of hurricanes and 2023 will see an even larger and more high-tech fleet.


Conformal Prediction Bands for Two-Dimensional Functional Time Series

arXiv.org Machine Learning

Functional data analysis (FDA) (Ramsay and Silverman 2005) is naturally apt to represent and model this kind of data, as it allows preserving their continuous nature, and provides a rigorous mathematical framework. Among the others, Zhou and Pan 2014 analyzed temperature surfaces, presenting two approaches for Functional Principal Component Analysis (FPCA) of functions defined on a non-rectangular domain, Porro-Muñoz et al. 2014 focuses on image processing using FDA, while a novel regularization technique for Gaussian random fields on a rectangular domain has been proposed by Rakêt 2010 and applied to 2D electrophoresis images. Another bivariate smoothing approach in a penalized regression framework has been introduced by Ivanescu and Andrada 2013, allowing for the estimation of functional parameters of two-dimensional functional data. As shown by Gervini 2010, even mortality rates can be interpreted as two-dimensional functional data. Whereas in all the reviewed works functions are assumed to be realization of iid or at least exchangeable random objects, to the best of our knowledge there is no literature focusing on forecasting time-dependent two-dimensional functional data. In this work, we focus on time series of surfaces, representing them as two-dimensional Functional Time Series (FTS).


Do Models Explain Themselves? Counterfactual Simulatability of Natural Language Explanations

arXiv.org Artificial Intelligence

Large language models (LLMs) are trained to imitate humans to explain human decisions. However, do LLMs explain themselves? Can they help humans build mental models of how LLMs process different inputs? To answer these questions, we propose to evaluate $\textbf{counterfactual simulatability}$ of natural language explanations: whether an explanation can enable humans to precisely infer the model's outputs on diverse counterfactuals of the explained input. For example, if a model answers "yes" to the input question "Can eagles fly?" with the explanation "all birds can fly", then humans would infer from the explanation that it would also answer "yes" to the counterfactual input "Can penguins fly?". If the explanation is precise, then the model's answer should match humans' expectations. We implemented two metrics based on counterfactual simulatability: precision and generality. We generated diverse counterfactuals automatically using LLMs. We then used these metrics to evaluate state-of-the-art LLMs (e.g., GPT-4) on two tasks: multi-hop factual reasoning and reward modeling. We found that LLM's explanations have low precision and that precision does not correlate with plausibility. Therefore, naively optimizing human approvals (e.g., RLHF) may not be a sufficient solution.


Quaternion Convolutional Neural Networks: Current Advances and Future Directions

arXiv.org Artificial Intelligence

Since their first applications, Convolutional Neural Networks (CNNs) have solved problems that have advanced the state-of-the-art in several domains. CNNs represent information using real numbers. Despite encouraging results, theoretical analysis shows that representations such as hyper-complex numbers can achieve richer representational capacities than real numbers, and that Hamilton products can capture intrinsic interchannel relationships. Moreover, in the last few years, experimental research has shown that Quaternion-Valued CNNs (QCNNs) can achieve similar performance with fewer parameters than their real-valued counterparts. This paper condenses research in the development of QCNNs from its very beginnings. We propose a conceptual organization of current trends and analyze the main building blocks used in the design of QCNN models. Based on this conceptual organization, we propose future directions of research.


Russian forces 'intercept eight Ukrainian drones over Crimea'

Al Jazeera

Russia's air defence forces and fleet in the Black Sea have shot down eight Ukrainian drones over the Crimean port of Sevastopol, according to a Moscow-installed official. Mikhail Razvozhayev, the Russian-installed governor of Sevastopol, said the drone attack took place early on Sunday over the port of Sevastopol and the city's Balaklava and Khersones districts. "No objects, either in the city or in the water area were damaged," he said on the Telegram messaging app. One drone was shot down over the sea, five were intercepted by Russia's electronic warfare forces and two water surface drones were destroyed on the outer shore, he added. There was no immediate comment from Kyiv on the attack on the Crimean Peninsula, which Russia annexed from Ukraine in 2014.


Submersible robots that can fly

Robohub

Last month, the entire world was abuzz when five über wealthy explorers perished at the bottom of the Atlantic Ocean near the grave of the once "unsinkable ship." Disturbingly, during the same week, hundreds of war-torn refugees drowned in the Mediterranean with little news of their plight. The irony of machine versus nature illustrates how tiny humans are in the universe, and that every soul rich or poor is precious. It is with this attitude that many roboticists have been tackling some of the hardest problems in the galaxy from space exploration to desert mining to oceanography to search & rescue. Following the news of the implosion of the Titan submersible, I reached out to Professor F. Javier Diez of Rutgers University for his comment on the rescue mission and the role of robots.


Linear Classification of Neural Manifolds with Correlated Variability

arXiv.org Machine Learning

Understanding how the statistical and geometric properties of neural activity relate to performance is a key problem in theoretical neuroscience and deep learning. Here, we calculate how correlations between object representations affect the capacity, a measure of linear separability. We show that for spherical object manifolds, introducing correlations between centroids effectively pushes the spheres closer together, while introducing correlations between the axes effectively shrinks their radii, revealing a duality between correlations and geometry with respect to the problem of classification. We then apply our results to accurately estimate the capacity of deep network data.


Aeolus Ocean -- A simulation environment for the autonomous COLREG-compliant navigation of Unmanned Surface Vehicles using Deep Reinforcement Learning and Maritime Object Detection

arXiv.org Artificial Intelligence

Heading towards navigational autonomy in unmanned surface vehicles (USVs) in the maritime sector can fundamentally lead towards safer waters as well as reduced operating costs, while also providing a range of exciting new capabilities for oceanic research, exploration and monitoring. However, achieving such a goal is challenging. USV control systems must, safely and reliably, be able to adhere to the international regulations for preventing collisions at sea (COLREGs) in encounters with other vessels as they navigate to a given waypoint while being affected by realistic weather conditions, either during the day or at night. To deal with the multitude of possible scenarios, it is critical to have a virtual environment that is able to replicate the realistic operating conditions USVs will encounter, before they can be implemented in the real world. Such "digital twins" form the foundations upon which Deep Reinforcement Learning (DRL) and Computer Vision (CV) algorithms can be used to develop and guide USV control systems. In this paper we describe the novel development of a COLREG-compliant DRL-based collision avoidant navigational system with CV-based awareness in a realistic ocean simulation environment. The performance of the trained autonomous Agents resulting from this approach is evaluated in several successful navigations to set waypoints in both open sea and coastal encounters with other vessels. A binary executable version of the simulator with trained agents is available at https://github.com/aavek/Aeolus-Ocean


Full text: NATO Vilnius summit communique

Al Jazeera

NATO leaders are holding their annual summit as Ukraine looks to the security alliance for support in its attempt to push back invading Russian forces. The Vilnius communique, however, while emphasising NATO's support for Ukraine, gave no clear timetable on when the country might be able to join the alliance, in a major disappointment for Ukrainian President Volodymyr Zelenskyy, who had travelled to the Lithuanian capital. "Ukraine's future is in NATO," the leaders said in the joint statement on Tuesday. "We will be in a position to extend an invitation to Ukraine to join the alliance when allies agree and conditions are met," the declaration said, without specifying the conditions. The communique also touched on the Asia Pacific, with the leaders of Australia, Japan, New Zealand and South Korea all attending as NATO allies. It said China was a challenge to NATO's interests, security and values with its "ambitions and coercive policies" triggering a furious response from Beijing. And it accused Beijing and Moscow of "mutually reinforcing attempts to undercut the rules-based international order". China has said it wants peace in Ukraine, but has not condemned Russia's full scale invasion since it began in February 2022. NATO is a defensive Alliance. It is the unique, essential and indispensable transatlantic forum to consult, coordinate and act on all matters related to our individual and collective security. We reaffirm our iron-clad commitment to defend each other and every inch of Allied territory at all times, protect our one billion citizens, and safeguard our freedom and democracy, in accordance with Article 5 of the Washington Treaty. We will continue to ensure our collective defence from all threats, no matter where they stem from, based on a 360-degree approach, to fulfil NATO's three core tasks of deterrence and defence, crisis prevention and management, and cooperative security. We adhere to international law and to the purposes and principles of the Charter of the United Nations and are committed to upholding the rules-based international order. This Summit marks a milestone in strengthening our Alliance. We look forward to our valuable exchanges with the Heads of State and Government of Australia, Japan, New Zealand, and the Republic of Korea, as well as the President of the European Council and the President of the European Commission at this Summit. We also welcome the engagements with the Foreign Ministers of Georgia and the Republic of Moldova, and with the Deputy Foreign Minister of Bosnia and Herzegovina, as we continue to consult closely on the implementation of NATO's tailored support measures. This is an historic step for Finland and for NATO. For many years, we worked closely as partners; we now stand together as Allies. NATO membership makes Finland safer, and NATO stronger. Every nation has the right to choose its own security arrangements.


Distributed Convex Optimization "Over-the-Air" in Dynamic Environments

arXiv.org Artificial Intelligence

This paper presents a decentralized algorithm for solving distributed convex optimization problems in dynamic networks with time-varying objectives. The unique feature of the algorithm lies in its ability to accommodate a wide range of communication systems, including previously unsupported ones, by abstractly modeling the information exchange in the network. Specifically, it supports a novel communication protocol based on the "over-the-air" function computation (OTA-C) technology, that is designed for an efficient and truly decentralized implementation of the consensus step of the algorithm. Unlike existing OTA-C protocols, the proposed protocol does not require the knowledge of network graph structure or channel state information, making it particularly suitable for decentralized implementation over ultra-dense wireless networks with time-varying topologies and fading channels. Furthermore, the proposed algorithm synergizes with the "superiorization" methodology, allowing the development of new distributed algorithms with enhanced performance for the intended applications. The theoretical analysis establishes sufficient conditions for almost sure convergence of the algorithm to a common time-invariant solution for all agents, assuming such a solution exists. Our algorithm is applied to a real-world distributed random field estimation problem, showcasing its efficacy in terms of convergence speed, scalability, and spectral efficiency. Furthermore, we present a superiorized version of our algorithm that achieves faster convergence with significantly reduced energy consumption compared to the unsuperiorized algorithm.