Atlantic Ocean
Deputy Russian army commander killed in Ukraine: Official
The deputy commander of Russia's 14th Army Corps, Major-General Vladimir Zavadsky, has been killed in Ukraine, a top regional official confirmed. Zavadsky died "at a combat post in the special operation zone", Alexander Gusev, the governor of Russia's Voronezh region, said on Monday without providing any further details. The "special military operation" is the term Russia uses to describe the war in Ukraine, which it launched in February 2022. Gusev paid tribute to Zavadsky, calling him "a courageous officer, a real general and a worthy man". Zavadsky's death marked the seventh major-general confirmed dead by Russia, making him the 12th senior officer reported deceased since the onset of the war, investigative news outlet iStories reported. Meanwhile, on Tuesday, Ukrainian authorities reported that their military successfully downed 10 out of 17 attack drones launched by Russia overnight.
Active Learning for Abrupt Shifts Change-point Detection via Derivative-Aware Gaussian Processes
Change-point detection (CPD) is crucial for identifying abrupt shifts in data, which influence decision-making and efficient resource allocation across various domains. To address the challenges posed by the costly and time-intensive data acquisition in CPD, we introduce the Derivative-Aware Change Detection (DACD) method. It leverages the derivative process of a Gaussian process (GP) for Active Learning (AL), aiming to pinpoint change-point locations effectively. DACD balances the exploitation and exploration of derivative processes through multiple data acquisition functions (AFs). By utilizing GP derivative mean and variance as criteria, DACD sequentially selects the next sampling data point, thus enhancing algorithmic efficiency and ensuring reliable and accurate results. We investigate the effectiveness of DACD method in diverse scenarios and show it outperforms other active learning change-point detection approaches.
Estimation of Physical Parameters of Waveforms With Neural Networks
Jamal, Saad Ahmed, Corpetti, Thomas, Tiede, Dirk, Letard, Mathilde, Lague, Dimitri
Light Detection and Ranging (LiDAR) are fast emerging sensors in the field of Earth Observation. It is a remote sensing technology that utilizes laser beams to measure distances and create detailed three-dimensional representations of objects and environments. The potential of Full Waveform LiDAR is much greater than just height estimation and 3D reconstruction only. Overall shape of signal provides important information about properties of water body. However, the shape of FWL is unexplored as most LiDAR software work on point cloud by utilizing the maximum value within the waveform. Existing techniques in the field of LiDAR data analysis include depth estimation through inverse modeling and regression of logarithmic intensity and depth for approximating the attenuation coefficient. However, these methods suffer from limitations in accuracy. Depth estimation through inverse modeling provides only approximate values and does not account for variations in surface properties, while the regression approach for the attenuation coefficient is only able to generalize a value through several data points which lacks precision and may lead to significant errors in estimation. Additionally, there is currently no established modeling method available for predicting bottom reflectance. This research proposed a novel solution based on neural networks for parameter estimation in LIDAR data analysis. By leveraging the power of neural networks, the proposed solution successfully learned the inversion model, was able to do prediction of parameters such as depth, attenuation coefficient, and bottom reflectance. Performance of model was validated by testing it on real LiDAR data. In future, more data availability would enable more accuracy and reliability of such models.
Do AI models produce better weather forecasts than physics-based models? A quantitative evaluation case study of Storm Ciar\'an
Charlton-Perez, Andrew J., Dacre, Helen F., Driscoll, Simon, Gray, Suzanne L., Harvey, Ben, Harvey, Natalie J., Hunt, Kieran M. R., Lee, Robert W., Swaminathan, Ranjini, Vandaele, Remy, Volonté, Ambrogio
There has been huge recent interest in the potential of making operational weather forecasts using machine learning techniques. As they become a part of the weather forecasting toolbox, there is a pressing need to understand how well current machine learning models can simulate high-impactweather events. We compare forecasts of Storm Ciar\'an, a European windstorm that caused sixteen deaths and extensive damage in Northern Europe, made by machine learning and numericalweather prediction models. The four machine learning models considered (FourCastNet, Pangu-Weather, GraphCast and FourCastNet-v2) produce forecasts that accurately capture the synoptic-scale structure of the cyclone including the position of the cloud head, shape of the warm sector and location of warm conveyor belt jet, and the large-scale dynamical drivers important for the rapid storm development such as the position of the storm relative to the upper-level jet exit. However, their ability to resolve the more detailed structures important for issuing weather warnings is more mixed. All of the machine learning models underestimate the peak amplitude of winds associated with the storm, only some machine learning models resolve the warm core seclusion and none of the machine learning models capture the sharp bent-back warm frontal gradient. Our study shows there is a great deal about the performance and properties of machine learning weather forecasts that can be derived from case studies of high-impact weather events such as Storm Ciar\'an.
Statistical exploration of the Manifold Hypothesis
Whiteley, Nick, Gray, Annie, Rubin-Delanchy, Patrick
The Manifold Hypothesis is a widely accepted tenet of Machine Learning which asserts that nominally high-dimensional data are in fact concentrated near a low-dimensional manifold, embedded in high-dimensional space. This phenomenon is observed empirically in many real world situations, has led to development of a wide range of statistical methods in the last few decades, and has been suggested as a key factor in the success of modern AI technologies. We show that rich and sometimes intricate manifold structure in data can emerge from a generic and remarkably simple statistical model -- the Latent Metric Model -- via elementary concepts such as latent variables, correlation and stationarity. This establishes a general statistical explanation for why the Manifold Hypothesis seems to hold in so many situations. Informed by the Latent Metric Model we derive procedures to discover and interpret the geometry of high-dimensional data, and explore hypotheses about the data generating mechanism. These procedures operate under minimal assumptions and make use of well known, scaleable graph-analytic algorithms.
US warship shoots down three Houthi drones targeting commercial vessels in Red Sea: CENTCOM
NSC Communications Coordinator John Kirby responds to progressive pushback against U.S. aid to Israel on'FOX News Sunday.' Three commercial vessels were attacked in the Red Sea on Sunday, prompting a U.S. warship to shoot down multiple unmanned aerial vehicles (UAV) headed toward them. The development could signify a serious escalation in a series of maritime attacks in the Middle East linked to the Israel-Hamas war. "Today, there were four attacks against three separate commercial vessels operating in international waters in the southern Red Sea," a statement by U.S. Central Command (CENTCOM) explained. "These three vessels are connected to 14 separate nations." The USS Carney was in the southern Red Sea, just north of the Bab al-Mandab Strait, when it shot down three Houthi drones heading in its direction, a U.S. official told Fox News, adding that the action was taken in self-defense. The drones were launched from Houthi-controlled areas of Yemen, the official claimed.
Explainable AI is Responsible AI: How Explainability Creates Trustworthy and Socially Responsible Artificial Intelligence
Artificial intelligence (AI) has been clearly established as a technology with the potential to revolutionize fields from healthcare to finance - if developed and deployed responsibly. This is the topic of responsible AI, which emphasizes the need to develop trustworthy AI systems that minimize bias, protect privacy, support security, and enhance transparency and accountability. Explainable AI (XAI) has been broadly considered as a building block for responsible AI (RAI), with most of the literature considering it as a solution for improved transparency. This work proposes that XAI and responsible AI are significantly more deeply entwined. In this work, we explore state-of-the-art literature on RAI and XAI technologies. Based on our findings, we demonstrate that XAI can be utilized to ensure fairness, robustness, privacy, security, and transparency in a wide range of contexts. Our findings lead us to conclude that XAI is an essential foundation for every pillar of RAI.
Bridging Background Knowledge Gaps in Translation with Automatic Explicitation
Han, HyoJung, Boyd-Graber, Jordan Lee, Carpuat, Marine
Translations help people understand content written in another language. However, even correct literal translations do not fulfill that goal when people lack the necessary background to understand them. Professional translators incorporate explicitations to explain the missing context by considering cultural differences between source and target audiences. Despite its potential to help users, NLP research on explicitation is limited because of the dearth of adequate evaluation methods. This work introduces techniques for automatically generating explicitations, motivated by WikiExpl: a dataset that we collect from Wikipedia and annotate with human translators. The resulting explicitations are useful as they help answer questions more accurately in a multilingual question answering framework.
Auto-encoding GPS data to reveal individual and collective behaviour
Chabert-Liddell, Saint-Clair, Bez, Nicolas, Gloaguen, Pierre, Donnet, Sophie, Mahévas, Stéphanie
We propose an innovative and generic methodology to analyse individual and collective behaviour through individual trajectory data. The work is motivated by the analysis of GPS trajectories of fishing vessels collected from regulatory tracking data in the context of marine biodiversity conservation and ecosystem-based fisheries management. We build a low-dimensional latent representation of trajectories using convolutional neural networks as non-linear mapping. This is done by training a conditional variational auto-encoder taking into account covariates. The posterior distributions of the latent representations can be linked to the characteristics of the actual trajectories. The latent distributions of the trajectories are compared with the Bhattacharyya coefficient, which is well-suited for comparing distributions. Using this coefficient, we analyse the variation of the individual behaviour of each vessel during time. For collective behaviour analysis, we build proximity graphs and use an extension of the stochastic block model for multiple networks. This model results in a clustering of the individuals based on their set of trajectories. The application to French fishing vessels enables us to obtain groups of vessels whose individual and collective behaviours exhibit spatio-temporal patterns over the period 2014-2018.
Defense Against Smart Invaders with Swarms of Sweeping Agents
Francos, Roee M., Bruckstein, Alfred M.
The goal of this research is to devise guaranteed defense policies that allow to protect a given region from the entrance of smart mobile invaders by detecting them using a team of defending agents equipped with identical line sensors. By designing cooperative defense strategies that ensure all invaders are detected, conditions on the defenders' speed are derived. Successful accomplishment of the defense task implies invaders with a known limit on their speed cannot slip past the defenders and enter the guarded region undetected. The desired outcome of the defense protocols is to defend the area and additionally to expand it as much as possible. Expansion becomes possible if the defenders' speed exceeds a critical speed that is necessary to only defend the initial region. We present results on the total search time, critical speeds and maximal expansion possible for two types of novel pincer-movement defense processes, circular and spiral, for any even number of defenders. The proposed spiral process allows to detect invaders at nearly the lowest theoretically optimal speed, and if this speed is exceeded, it also allows to expand the protected region almost to the maximal area.