Atlantic Ocean
Dinosaur with scissor-like claws roamed Britain 168 million years ago
Mysterious ancient teeth found in three English counties are believed to belong to a dinosaur with scissor-like claws which roamed Britain 168 million years ago. Paleontologists said the fossils unearthed in Oxfordshire, Gloucestershire and Dorset were the first ever examples of therizinosaur and troodontid dinosaurs on UK soil. Not only that, but the remains are the world's oldest-known evidence of those species and could represent some of the earliest relatives of birds ever discovered. Therizinosaurus – which featured in the most recent Jurassic World film – was a large herbivore dinosaur from the late Cretaceous known for its distinctive long scissor-like claw bones. Along with the troodontid and well-known Velociraptor, it belonged to a group of ancient creatures called the maniraptorans.
Ukraine's Quest for Homegrown AI Drones to Take On Russia
The war in Ukraine, now into its 14th grueling month, has displaced millions, sparked global food shortages, and threatened to spiral into wider conflict. It has also highlighted how new technologies--especially ones drawn from the commercial sector--are upending conventional military doctrine. Ukraine has resisted and repelled Russia's much larger military force, thanks in large part to a willingness, borne of necessity, to adopt and experiment with novel technologies, not all of them originally designed for military use. I recently spoke with Ukraine's 32-year-old minister of digital transformation, Mykhailo Fedorov, about the country's interest in tapping new technology to boost the war effort. Fedorov spoke over Zoom, via an interpreter, from an undisclosed location in Ukraine, about plans to produce more sophisticated drones and other autonomous systems, and to incubate military startups.
'Eyes and ears': Could drones prove decisive in the Ukraine war?
Warning: Some readers may find some of the scenes described in this article disturbing. Kyiv, Ukraine – Ivan Ukraintsev, a stern-faced insurance broker turned director of a wartime charity providing crucial aid to Ukraine's military forces, is on a mission: to help Ukraine win the drone war. He is a polite but no-nonsense character, and he is here to talk about drones. "If we [Ukraine] had enough drones, we could end this war in two months," he says firmly. Ivan, who heads up the charity Starlife, had recently returned from overseeing a drone delivery to Bakhmut, a city in eastern Ukraine that has become the focal point for months of bloody battles between Ukrainian and Russian forces. Trench warfare, pockmarked and corpse-ridden swathes of no man's land, and constant artillery bombardments have drawn comparisons to battlefield conditions during World War I.
On the Opportunities and Challenges of Foundation Models for Geospatial Artificial Intelligence
Mai, Gengchen, Huang, Weiming, Sun, Jin, Song, Suhang, Mishra, Deepak, Liu, Ninghao, Gao, Song, Liu, Tianming, Cong, Gao, Hu, Yingjie, Cundy, Chris, Li, Ziyuan, Zhu, Rui, Lao, Ni
Large pre-trained models, also known as foundation models (FMs), are trained in a task-agnostic manner on large-scale data and can be adapted to a wide range of downstream tasks by fine-tuning, few-shot, or even zero-shot learning. Despite their successes in language and vision tasks, we have yet seen an attempt to develop foundation models for geospatial artificial intelligence (GeoAI). In this work, we explore the promises and challenges of developing multimodal foundation models for GeoAI. We first investigate the potential of many existing FMs by testing their performances on seven tasks across multiple geospatial subdomains including Geospatial Semantics, Health Geography, Urban Geography, and Remote Sensing. Our results indicate that on several geospatial tasks that only involve text modality such as toponym recognition, location description recognition, and US state-level/county-level dementia time series forecasting, these task-agnostic LLMs can outperform task-specific fully-supervised models in a zero-shot or few-shot learning setting. However, on other geospatial tasks, especially tasks that involve multiple data modalities (e.g., POI-based urban function classification, street view image-based urban noise intensity classification, and remote sensing image scene classification), existing foundation models still underperform task-specific models. Based on these observations, we propose that one of the major challenges of developing a FM for GeoAI is to address the multimodality nature of geospatial tasks. After discussing the distinct challenges of each geospatial data modality, we suggest the possibility of a multimodal foundation model which can reason over various types of geospatial data through geospatial alignments. We conclude this paper by discussing the unique risks and challenges to develop such a model for GeoAI.
Towards Spatio-temporal Sea Surface Temperature Forecasting via Static and Dynamic Learnable Personalized Graph Convolution Network
Li, Xiaohan, Zhang, Gaowei, Huang, Kai, He, Zhaofeng
Sea surface temperature (SST) is uniquely important to the Earth's atmosphere since its dynamics are a major force in shaping local and global climate and profoundly affect our ecosystems. Accurate forecasting of SST brings significant economic and social implications, for example, better preparation for extreme weather such as severe droughts or tropical cyclones months ahead. However, such a task faces unique challenges due to the intrinsic complexity and uncertainty of ocean systems. Recently, deep learning techniques, such as graphical neural networks (GNN), have been applied to address this task. Even though these methods have some success, they frequently have serious drawbacks when it comes to investigating dynamic spatiotemporal dependencies between signals. To solve this problem, this paper proposes a novel static and dynamic learnable personalized graph convolution network (SD-LPGC). Specifically, two graph learning layers are first constructed to respectively model the stable long-term and short-term evolutionary patterns hidden in the multivariate SST signals. Then, a learnable personalized convolution layer is designed to fuse this information. Our experiments on real SST datasets demonstrate the state-of-the-art performances of the proposed approach on the forecasting task.
Feed-forward Disturbance Compensation for Station Keeping in Wave-dominated Environments
Walker, Kyle L., Stokes, Adam A., Kiprakis, Aristides, Giorgio-Serchi, Francesco
When deploying robots in shallow ocean waters, wave disturbances can be significant, highly dynamic and pose problems when operating near structures; this is a key limitation of current control strategies, restricting the range of conditions in which subsea vehicles can be deployed. To improve dynamic control and offer a higher level of robustness, this work proposes a Cascaded Proportional-Derivative (C-PD) with Feed-forward (FF) control scheme for disturbance mitigation, exploring the concept of explicitly using disturbance estimations to counteract state perturbations. Results demonstrate that the proposed controller is capable of higher performance in contrast to a standard C-PD controller, with an average reduction of ~48% witnessed across various sea states. Additional analysis also investigated performance when considering coarse estimations featuring inaccuracies; average improvements of ~17% demonstrate the effectiveness of the proposed strategy to handle these uncertainties. The proposal in this work shows promise for improved control without a drastic increase in required computing power; if coupled with sufficient sensors, state estimation techniques and prediction algorithms, utilising feed-forward compensating control actions offers a potential solution to improve vehicle control under wave-induced disturbances.
Ukraine likely to face bloody Crimea fight, satellite images show
An analysis of satellite images by Al Jazeera has revealed that Russian forces are fortifying the Crimean peninsula in anticipation of a Ukrainian attempt to recapture it. Experts say that those defences are likely to make any such effort difficult and bloody. As the war grinds on for more than a year, Ukraine's political and military leadership has made it clear that it defines victory as reclaiming its 1991 borders, which Russia had recognised. The United Nations and all of Ukraine's Western allies also recognise those borders, which include Crimea. The investigation by Al Jazeera's Sanad news verification and monitoring unit found that between February and March, the Crimean border and surrounding areas were transformed into a fortified barrier ahead of an expected spring counteroffensive by Ukrainian forces.
Statistical and computational rates in high rank tensor estimation
Higher-order tensor datasets arise commonly in recommendation systems, neuroimaging, and social networks. Here we develop probable methods for estimating a possibly high rank signal tensor from noisy observations. We consider a generative latent variable tensor model that incorporates both high rank and low rank models, including but not limited to, simple hypergraphon models, single index models, low-rank CP models, and low-rank Tucker models. Comprehensive results are developed on both the statistical and computational limits for the signal tensor estimation. We find that high-dimensional latent variable tensors are of log-rank; the fact explains the pervasiveness of low-rank tensors in applications. Furthermore, we propose a polynomial-time spectral algorithm that achieves the computationally optimal rate. We show that the statistical-computational gap emerges only for latent variable tensors of order 3 or higher. Numerical experiments and two real data applications are presented to demonstrate the practical merits of our methods.
Anomalous NO2 emitting ship detection with TROPOMI satellite data and machine learning
Kurchaba, Solomiia, van Vliet, Jasper, Verbeek, Fons J., Veenman, Cor J.
Starting from 2021, more demanding $\text{NO}_\text{x}$ emission restrictions were introduced for ships operating in the North and Baltic Sea waters. Since all methods currently used for ship compliance monitoring are financially and time demanding, it is important to prioritize the inspection of ships that have high chances of being non-compliant. The current state-of-the-art approach for a large-scale ship $\text{NO}_\text{2}$ estimation is a supervised machine learning-based segmentation of ship plumes on TROPOMI/S5P images. However, challenging data annotation and insufficiently complex ship emission proxy used for the validation limit the applicability of the model for ship compliance monitoring. In this study, we present a method for the automated selection of potentially non-compliant ships using a combination of machine learning models on TROPOMI satellite data. It is based on a proposed regression model predicting the amount of $\text{NO}_\text{2}$ that is expected to be produced by a ship with certain properties operating in the given atmospheric conditions. The model does not require manual labeling and is validated with TROPOMI data directly. The differences between the predicted and actual amount of produced $\text{NO}_\text{2}$ are integrated over observations of the ship in time and are used as a measure of the inspection worthiness of a ship. To assure the robustness of the results, we compare the obtained results with the results of the previously developed segmentation-based method. Ships that are also highly deviating in accordance with the segmentation method require further attention. If no other explanations can be found by checking the TROPOMI data, the respective ships are advised to be the candidates for inspection.
Supervised segmentation of NO2 plumes from individual ships using TROPOMI satellite data
Kurchaba, Solomiia, van Vliet, Jasper, Verbeek, Fons J., Meulman, Jacqueline J., Veenman, Cor J.
The shipping industry is one of the strongest anthropogenic emitters of $\text{NO}_\text{x}$ -- substance harmful both to human health and the environment. The rapid growth of the industry causes societal pressure on controlling the emission levels produced by ships. All the methods currently used for ship emission monitoring are costly and require proximity to a ship, which makes global and continuous emission monitoring impossible. A promising approach is the application of remote sensing. Studies showed that some of the $\text{NO}_\text{2}$ plumes from individual ships can visually be distinguished using the TROPOspheric Monitoring Instrument on board the Copernicus Sentinel 5 Precursor (TROPOMI/S5P). To deploy a remote sensing-based global emission monitoring system, an automated procedure for the estimation of $\text{NO}_\text{2}$ emissions from individual ships is needed. The extremely low signal-to-noise ratio of the available data as well as the absence of ground truth makes the task very challenging. Here, we present a methodology for the automated segmentation of $\text{NO}_\text{2}$ plumes produced by seagoing ships using supervised machine learning on TROPOMI/S5P data. We show that the proposed approach leads to a more than a 20\% increase in the average precision score in comparison to the methods used in previous studies and results in a high correlation of 0.834 with the theoretically derived ship emission proxy. This work is a crucial step toward the development of an automated procedure for global ship emission monitoring using remote sensing data.