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Multivariate Functional Singular Spectrum Analysis Over Different Dimensional Domains

arXiv.org Machine Learning

A common problem in time series analysis is detection, extraction, and exploration of mean, seasonal, trend, and noise components in time series data. A technique known as singular spectrum analysis (SSA) has been developed as a nonparametric, exploratory method which can be used to identify such interesting components in ordinary time series where observations are scalars (Golyandina et al., 2001). Often times, many variables are observed as a result of a single stochastic process and investigation of time series components can be made richer by performing a multivariate analysis of these vector observations. The MSSA algorithm is a technique that has seen success over its univariate SSA counterpart in decomposing a multidimensional time series into components if the covariates are moderately correlated (Golyandina and Stepanov, 2012). MSSA also has been broken up into two approaches of vertical MSSA (VMSSA) and horizontal MSSA (HMSSA) where VMSSA involves the vertical stacking of univariate Hankel trajectory matrices while HMSSA works with the horizontal stacking of the same elements (Hassani and Mahmoudvand, 2018). Over the course of the last 15 years, MSSA has seen significant success in various areas of application see Groth and Ghil (2011); Golyandina and Stepanov (2012); Silva et al. (2018); Hassani et al. (2019). Functional data analysis embodies the evaluation and exploration of data that is comprised of functions such as curves or surfaces (Ramsay and Silverman, 2005). Functional PCA (FPCA) is a technique that is used to find the most informative directions in a timeindependent collection of functional subjects (Ramsay and Silverman, 2005). Univariate Functional Singular Spectrum Analysis (FSSA) was developed by Haghbin et al. (2019) as a novel technique that is used to decompose a time-dependent collection of functional


Quantum Criticism: A Tagged News Corpus Analysed for Sentiment and Named Entities

arXiv.org Machine Learning

Several custom web scrapers were created for retrieving news articles from various online news organizations. All web scrapers were run every two hours to retrieve articles from the following five news sites: the Atlantic, the British Broadcasting Corporation (BBC) News, Fox News, the New York Times and Slate Magazine. Web scrapers continue to run every two hours in perpetuity, scraping additional news articles. Collectively, the web scrapers used each news organization's RSS feed as input, storing the scraped output into a custom database. Article URLs were used for disambiguation; where two scraped articles shared a URL, the most recently retrieved article replaced previous versions of articles. As of November 2019, we collected a total of 105,000 news articles from five media organizations. Figure 2 depicts the number of cumulative articles scraped for each news organization over time. Even though articles from Fox News were regularly scraped four months later than other news sources, the number of articles scraped rose quickly, and now constitutes the news organization with the most scraped articles. Given the news scrapers run at regularly scheduled two-hour intervals for all news organization, this suggests that Fox News updates its RSS feed with new articles far more often than others, and the Atlantic updates its RSS feed far less frequently than others.


British treasure finders accused of piracy

Daily Mail - Science & tech

British archaeologists who discovered hundreds of artefacts from a cluster of 17th century shipwrecks in the Mediterranean Sea have had their cargo seized and been accused of an'illicit excavation'. Enigma Recoveries, which led an expedition into the Levantine Basin off the coast of Cyprus, found 12 shipwrecks filled with Chinese porcelain, jugs, coffee pots, peppercorns and illicit tobacco pipes. The ships and their priceless cargo, hailed as the'archaeological equivalent of finding a new planet' were recovered in ancient'shipping lanes' that served spice and silk trades from 300 BC onwards. But in a strongly-worded statement, the Cypriot government accused the company of being well known to both Cyprus and UNESCO for its'illicit underwater excavations' and its'violent extraction of objects causing destruction to their context'. Cyprus's Department of Antiquities accused the company of intending to sell the objects, as allegedly evident in documents filed with the United States Securities and Exchange Commission (NASDAQ).


Russian rocket disintegrates in Earth's orbit leaving behind 65 pieces

Daily Mail - Science & tech

A Russian rocket used to launch a scientific satellite into space has broken apart after nine years in orbit - leaving a dozens of pieces of debris around the Earth. The Fregat-SB is a type of space tug and its upper stage was left floating after it helped deliver the Spektr-R satellite in 2011, according to Roscosmos. Spektr-R was a radio telescope launched by the Russian space agency but it stopped responding to ground control last year and was declared dead in May 2019. Roscosmos confirmed the breakdown of the rocket happened on May 8 between 06:00 and 07:00 BST somewhere above the Indian ocean. About two-thirds of the satellites orbiting the Earth are dead - about 3,000 of about 4,500 objects - and pose a'very big danger' to the planet - this also includes parts of the Russian rocket that disintegrated (artist's impression) The Russian space agency is studying data to find out how many parts it broke up into and where they are currently orbiting the planet.


BlackBox: Generalizable Reconstruction of Extremal Values from Incomplete Spatio-Temporal Data

arXiv.org Machine Learning

We describe our submission to the Extreme Value Analysis 2019 Data Challenge in which teams were asked to predict extremes of sea surface temperature anomaly within spatio-temporal regions of missing data. We present a computational framework which reconstructs missing data using convolutional deep neural networks. Conditioned on incomplete data, we employ autoencoder-like models as multivariate conditional distributions from which possible reconstructions of the complete dataset are sampled using imputed noise. In order to mitigate bias introduced by any one particular model, a prediction ensemble is constructed to create the final distribution of extremal values. Our method does not rely on expert knowledge in order to accurately reproduce dynamic features of a complex oceanographic system with minimal assumptions. The obtained results promise reusability and generalization to other domains.


Impact of different belief facets on agents' decision -- a refined cognitive architecture

arXiv.org Artificial Intelligence

This paper presents a conceptual refinement of agent cognitive architecture inspired from the beliefs-desires-intentions (BDI) and the theory of planned behaviour (TPB) models, with an emphasis on different belief facets. This enables us to investigate the impact of personality and the way that an agent weights its internal beliefs and social sanctions on an agent's actions. The study also uses the concept of cognitive dissonance associated with the fairness of institutions to investigate the agents' behaviour. To showcase our model, we simulate two historical long-distance trading societies, namely Armenian merchants of New-Julfa and the English East India Company. The results demonstrate the importance of internal beliefs of agents as a pivotal aspect for following institutional rules.


Amazing drone footage shows feeding blue whales swimming to the surface

Daily Mail - Science & tech

Blue whales swim to the surface to feed on krill as it helps them to conserve energy, according to a new study that involved amazing drone footage of the mammals. Experts from Oregon State University found that feeding on the ocean's surface plays an important role in the hunt for food among New Zealand blue whales. Blue whales are the largest mammals on Earth and have to carefully balance the cost of energy they get from food with the cost of energy used in getting the food. Researchers say the marine mammals forage for krill in areas where they are densely packed and found near the surface of the water to cut their dive time. The Oregon team found that the blue whales do this to conserve on the energetic costs of feeding such as diving, holding their breath or opening their mouths.


12 shipwrecks uncovered in the east Med dating from 300 BC

Daily Mail - Science & tech

Archaeologists have found shipwrecks in the Mediterranean filled with hundreds of artefacts including Chinese porcelain, jugs, coffee pots, peppercorns and illicit tobacco pipes. A British-led expedition found a cluster of 12 ships on the sea bed, 1.2 miles below the surface of the Levantine Sea, using sophisticated robots. The ships were recovered in ancient'shipping lanes' that served spice and silk trades of the Greek, Roman and Ottoman empires, from 300 BC onwards. The ancient ships – including the biggest ever found in the Med – were unearthed in a muddy part of the eastern seabed between Cyprus and Lebanon, where remnants are often hard to find. The cluster of shipwrecks were found in the Levantine Basin in the east of the Mediterranean Sea.


Earth Observation data and Artificial Intelligence in support of Journalism

#artificialintelligence

Earth Observation data is valuable for journalist's reports to the public. An example are the maps released in little time during or after the tsunami in Indian Ocean in 2004 or the Fukushima disaster in 2011, accompanying the verbal or text reports of theirs. Taking advantage of the improved temporal frequency and spatial cover of the Sentinel satellite sensors SnapEarth aims to assimilate latest spaceborne retrieved information to support journalists in their work in near real time. In this context, a dedicated services' module aims to leverage on Copernicus monitoring services, like the EMS's (Emergency Management Service) EFAS (European Flood Awareness System) and EFFIS (European Forest Fire Information System). It will add in tandem to them the ability to exploit latest AI (Artificial Intelligence) techniques to automatically and unsupervised query through big data piles to deliver in minimum time required products.


Time series and machine learning to forecast the water quality from satellite data

arXiv.org Machine Learning

Managing the quality of water for present and future generations of coastal regions should be a central concern of both citizens and public officials. Remote sensing can contribute to the management and monitoring of coastal water and pollutants. Algal blooms are a coastal pollutant that is a cause of concern. Many satellite data, such as MODIS, have been used to generate water-quality products to detect the blooms such as chlorophyll a (Chl-a), a photosynthesis index called fluorescence line height (FLH), and sea surface temperature (SST). It is important to characterize the spatial and temporal variations of these water quality products by using the mathematical models of these products. However, for monitoring, pollution control boards will need nowcasts and forecasts of any pollution. Therefore, we aim to predict the future values of the MODIS Chl-a, FLH, and SST of the water. This will not be limited to one type of water but, rather, will cover different types of water varying in depth and turbidity. This is very significant because the temporal trend of Chl-a, FLH, and SST is dependent on the geospatial and water properties. For this purpose, we will decompose the time series of each pixel into several components: trend, intra-annual variations, seasonal cycle, and stochastic stationary. We explore three such time series machine learning models that can characterize the non-stationary time series data and predict future values, including the Seasonal ARIMA (Auto Regressive Integrated Moving Average) (SARIMA), regression, and neural network. The results indicate that all these methods are effective at modelling Chl-a, FLH, and SST time series and predicting the values reasonably well. However, regression and neural network are found to be the best at predicting Chl-a in all types of water (turbid and shallow). Meanwhile, the SARIMA model provides the best prediction of FLH and SST.