Atlantic Ocean
Robust detection and attribution of climate change under interventions
Székely, Enikő, Sippel, Sebastian, Meinshausen, Nicolai, Obozinski, Guillaume, Knutti, Reto
Fingerprints are key tools in climate change detection and attribution (D&A) that are used to determine whether changes in observations are different from internal climate variability (detection), and whether observed changes can be assigned to specific external drivers (attribution). We propose a direct D&A approach based on supervised learning to extract fingerprints that lead to robust predictions under relevant interventions on exogenous variables, i.e., climate drivers other than the target. We employ anchor regression, a distributionally-robust statistical learning method inspired by causal inference that extrapolates well to perturbed data under the interventions considered. The residuals from the prediction achieve either uncorrelatedness or mean independence with the exogenous variables, thus guaranteeing robustness. We define D&A as a unified hypothesis testing framework that relies on the same statistical model but uses different targets and test statistics. In the experiments, we first show that the CO2 forcing can be robustly predicted from temperature spatial patterns under strong interventions on the solar forcing. Second, we illustrate attribution to the greenhouse gases and aerosols while protecting against interventions on the aerosols and CO2 forcing, respectively. Our study shows that incorporating robustness constraints against relevant interventions may significantly benefit detection and attribution of climate change.
Matrix Profile XXVII: A Novel Distance Measure for Comparing Long Time Series
Der, Audrey, Yeh, Chin-Chia Michael, Wu, Renjie, Wang, Junpeng, Zheng, Yan, Zhuang, Zhongfang, Wang, Liang, Zhang, Wei, Keogh, Eamonn
The most useful data mining primitives are distance measures. With an effective distance measure, it is possible to perform classification, clustering, anomaly detection, segmentation, etc. For single-event time series Euclidean Distance and Dynamic Time Warping distance are known to be extremely effective. However, for time series containing cyclical behaviors, the semantic meaningfulness of such comparisons is less clear. For example, on two separate days the telemetry from an athlete workout routine might be very similar. The second day may change the order in of performing push-ups and squats, adding repetitions of pull-ups, or completely omitting dumbbell curls. Any of these minor changes would defeat existing time series distance measures. Some bag-of-features methods have been proposed to address this problem, but we argue that in many cases, similarity is intimately tied to the shapes of subsequences within these longer time series. In such cases, summative features will lack discrimination ability. In this work we introduce PRCIS, which stands for Pattern Representation Comparison in Series. PRCIS is a distance measure for long time series, which exploits recent progress in our ability to summarize time series with dictionaries. We will demonstrate the utility of our ideas on diverse tasks and datasets.
Kremlin Sees 'Risk' Of Ukraine Attacks On Crimea
The Kremlin said Thursday that the Moscow-annexed Crimean Peninsula was vulnerable to Ukrainian attacks after officials said they had shot down a drone near a key naval base. The latest drone attack comes after Russian President Vladimir Putin recently visited the only bridge connecting Crimea with the Russian mainland to survey work to repair the key artery damaged in a blast Moscow blamed on Kiyv. "There are certainly risks because the Ukrainian side continues its policy of organising terrorist attacks. But, on the other hand, information we get indicates that effective countermeasures are being taken," Kremlin spokesman Dmitry Peskov told reporters. The Moscow-appointed governor of Crimea Sergei Aksyonov said last month that Russia was strengthening fortifications on the peninsula in the wake of recent attacks.
Beware the Black Swan – Towards AI
Originally published on Towards AI the World's Leading AI and Technology News and Media Company. If you are building an AI-related product or service, we invite you to consider becoming an AI sponsor. At Towards AI, we help scale AI and technology startups. Let us help you unleash your technology to the masses. Nassim Taleb is a former financial derivatives trader and probability researcher, his book'The Black Swan: The Impact of the Highly Improbable' highlights how highly improbable events impact our daily life and financial markets.
Monocular Camera and Single-Beam Sonar-Based Underwater Collision-Free Navigation with Domain Randomization
Yang, Pengzhi, Liu, Haowen, Roznere, Monika, Li, Alberto Quattrini
Underwater navigation presents several challenges, including unstructured unknown environments, lack of reliable localization systems (e.g., GPS), and poor visibility. Furthermore, good-quality obstacle detection sensors for underwater robots are scant and costly; and many sensors like RGB-D cameras and LiDAR only work in-air. To enable reliable mapless underwater navigation despite these challenges, we propose a low-cost end-to-end navigation system, based on a monocular camera and a fixed single-beam echo-sounder, that efficiently navigates an underwater robot to waypoints while avoiding nearby obstacles. Our proposed method is based on Proximal Policy Optimization (PPO), which takes as input current relative goal information, estimated depth images, echo-sounder readings, and previous executed actions, and outputs 3D robot actions in a normalized scale. End-to-end training was done in simulation, where we adopted domain randomization (varying underwater conditions and visibility) to learn a robust policy against noise and changes in visibility conditions. The experiments in simulation and real-world demonstrated that our proposed method is successful and resilient in navigating a low-cost underwater robot in unknown underwater environments.
Is Ukraine's new drone a game-changer in the war?
Kyiv, Ukraine – A mysterious weapon struck a target deep in Russia's heartland. On Monday morning, a deafening roar that sounded like a landing jet plane woke up a town spreadeagled in the flat steppes of the Volga River region. According to surveillance camera footage, a lightning-like flash followed by a thunderous explosion shook Engels, named after the philosopher and home to more than 300,000 people. It hit one of Russia's largest and most important military airfields that hosts strategic Tupolev Tu-160 and Tu-95 bombers. The planes are capable of carrying nuclear warheads, and Moscow has repeatedly used them to rain non-nuclear missiles on Ukraine.
Major Broadcasters Launch NextGen TV on Seven Local Television Stations in Birmingham, AL
The leading television stations serving the Birmingham television market began broadcasting with NextGen TV, a revolutionary new digital broadcast technology. Today's launch includes WABM (ABC) and WDBB (ABC and CW), WIAT (CBS), WBRC (Fox), WVTM-TV (NBC), WTTO (CW), and WSES (Heroes and Icons). Based on the same fundamental technology as the Internet and digital apps, NextGen TV can support a wide range of features that are currently in development. In addition to providing a new, improved way for broadcasters to reach viewers with advanced emergency alerts, NextGen TV features stunning video with brilliant color, sharper images and deeper contrast to create a more life-like experience. NextGen TV adds a new dimension to TV viewing, with vibrant video and new Voice dialogue enhancement that brings voices to the foreground.
A Unified Survey on Anomaly, Novelty, Open-Set, and Out-of-Distribution Detection: Solutions and Future Challenges
Salehi, Mohammadreza, Mirzaei, Hossein, Hendrycks, Dan, Li, Yixuan, Rohban, Mohammad Hossein, Sabokrou, Mohammad
Machine learning models often encounter samples that are diverged from the training distribution. Failure to recognize an out-of-distribution (OOD) sample, and consequently assign that sample to an in-class label significantly compromises the reliability of a model. The problem has gained significant attention due to its importance for safety deploying models in open-world settings. Detecting OOD samples is challenging due to the intractability of modeling all possible unknown distributions. To date, several research domains tackle the problem of detecting unfamiliar samples, including anomaly detection, novelty detection, one-class learning, open set recognition, and out-of-distribution detection. Despite having similar and shared concepts, out-of-distribution, open-set, and anomaly detection have been investigated independently. Accordingly, these research avenues have not cross-pollinated, creating research barriers. While some surveys intend to provide an overview of these approaches, they seem to only focus on a specific domain without examining the relationship between different domains. This survey aims to provide a cross-domain and comprehensive review of numerous eminent works in respective areas while identifying their commonalities. Researchers can benefit from the overview of research advances in different fields and develop future methodology synergistically. Furthermore, to the best of our knowledge, while there are surveys in anomaly detection or one-class learning, there is no comprehensive or up-to-date survey on out-of-distribution detection, which our survey covers extensively. Finally, having a unified cross-domain perspective, we discuss and shed light on future lines of research, intending to bring these fields closer together.
A Deep Learning Architecture for Passive Microwave Precipitation Retrievals using CloudSat and GPM Data
Rahimi, Reyhaneh, Vahedizadeh, Sajad, Ebtehaj, Ardeshir
This paper presents an algorithm that relies on a series of dense and deep neural networks for passive microwave retrieval of precipitation. The neural networks learn from coincidences of brightness temperatures from the Global Precipitation Measurement (GPM) Microwave Imager (GMI) with the active precipitating retrievals from the Dual-frequency Precipitation Radar (DPR) onboard GPM as well as those from the {CloudSat} Profiling Radar (CPR). The algorithm first detects the precipitation occurrence and phase and then estimates its rate, while conditioning the results to some key ancillary information including parameters related to cloud microphysical properties. The results indicate that we can reconstruct the DPR rainfall and CPR snowfall with a detection probability of more than 0.95 while the probability of a false alarm remains below 0.08 and 0.03, respectively. Conditioned to the occurrence of precipitation, the unbiased root mean squared error in estimation of rainfall (snowfall) rate using DPR (CPR) data is less than 0.8 (0.1) mm/hr over oceans and land. Beyond methodological developments, comparing the results with ERA5 reanalysis and official GPM products demonstrates that the uncertainty in global satellite snowfall retrievals continues to be large while there is a good agreement among rainfall products. Moreover, the results indicate that CPR active snowfall data can improve passive microwave estimates of global snowfall while the current CPR rainfall retrievals should only be used for detection and not estimation of rates.
Holding AI to Account: Challenges for the Delivery of Trustworthy AI in Healthcare
Procter, Rob, Tolmie, Peter, Rouncefield, Mark
The need for AI systems to provide explanations for their behaviour is now widely recognised as key to their adoption. In this paper, we examine the problem of trustworthy AI and explore what delivering this means in practice, with a focus on healthcare applications. Work in this area typically treats trustworthy AI as a problem of Human-Computer Interaction involving the individual user and an AI system. However, we argue here that this overlooks the important part played by organisational accountability in how people reason about and trust AI in socio-technical settings. To illustrate the importance of organisational accountability, we present findings from ethnographic studies of breast cancer screening and cancer treatment planning in multidisciplinary team meetings to show how participants made themselves accountable both to each other and to the organisations of which they are members. We use these findings to enrich existing understandings of the requirements for trustworthy AI and to outline some candidate solutions to the problems of making AI accountable both to individual users and organisationally. We conclude by outlining the implications of this for future work on the development of trustworthy AI, including ways in which our proposed solutions may be re-used in different application settings.