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Related papers: Deep modeling of quasar variability

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We introduce a deep learning method to simulate the motion of particles trapped in a chaotic recirculating flame. The Lagrangian trajectories of particles, captured using a high-speed camera and subsequently reconstructed in 3-dimensional…

Machine Learning · Statistics 2018-12-13 Pai Liu , Jingwei Gan , Rajan K. Chakrabarty

Matter-antimatter asymmetry is one of the major unsolved problems in physics that can be probed through precision measurements of charge-parity symmetry violation at current and next-generation neutrino oscillation experiments. In this…

Instrumentation and Detectors · Physics 2019-11-07 Abhishek Abhishek , Wojciech Fedorko , Patrick de Perio , Nicholas Prouse , Julian Z. Ding

Recent economic events, including the global financial crisis and COVID-19 pandemic, have exposed limitations in linear Factor Augmented Vector Autoregressive (FAVAR) models for forecasting and structural analysis. Nonlinear dimension…

Machine Learning · Statistics 2025-03-07 Yiyong Luo , Brooks Paige , Jim Griffin

Optical spectra contain a wealth of information about the physical properties and formation histories of galaxies. Often though, spectra are too noisy for this information to be accurately retrieved. In this study, we explore how machine…

Astrophysics of Galaxies · Physics 2023-10-17 M. Scourfield , A. Saintonge , D. de Mijolla , S. Viti

Probabilistic forecasting of high dimensional multivariate time series is a notoriously challenging task, both in terms of computational burden and distribution modeling. Most previous work either makes simple distribution assumptions or…

Machine Learning · Computer Science 2021-01-27 Nam Nguyen , Brian Quanz

The problem of estimating event truths from conflicting agent opinions in a social network is investigated. An autoencoder learns the complex relationships between event truths, agent reliabilities and agent observations. A Bayesian network…

Machine Learning · Computer Science 2021-01-26 Jielong Yang , Wee Peng Tay

Autoencoders are unsupervised models which have been used for detecting anomalies in multi-sensor environments. A typical use includes training a predictive model with data from sensors operating under normal conditions and using the model…

Machine Learning · Computer Science 2021-07-29 Bang Xiang Yong , Yasmin Fathy , Alexandra Brintrup

For centuries, scientists have observed nature to understand the laws that govern the physical world. The traditional process of turning observations into physical understanding is slow. Imperfect models are constructed and tested to…

Machine Learning · Computer Science 2023-01-27 M. Giselle Fernández-Godino , Donald D. Lucas , Qingkai Kong

Machine learning can provide powerful tools to detect patterns in multi-dimensional parameter space. We use K-means -a simple yet powerful unsupervised clustering algorithm which picks out structure in unlabeled data- to study a sample of…

Astrophysics of Galaxies · Physics 2016-03-11 Aycha Tammour , Sarah C. Gallagher , Mark Daley , Gordon T. Richards

The light scattered by an extrasolar Earth-like planet's surface and atmosphere will vary in intensity and color as the planet rotates; the resulting light curve will contain information about the planet's properties. Since most of the…

Astrophysics · Physics 2007-05-23 Eric B. Ford , Sara Seager , Edwin L. Turner

Autoencoders and generative neural network models have recently gained popularity in fluid mechanics due to their spontaneity and low processing time instead of high fidelity CFD simulations. Auto encoders are used as model order reduction…

Fluid Dynamics · Physics 2022-03-04 Kanishk , Tanishk Nandal , Prince Tyagi , Raj Kumar Singh

Machine-learning models have demonstrated a great ability to learn complex patterns and make predictions. In high-dimensional nonlinear problems of fluid dynamics, data representation often greatly affects the performance and…

Fluid Dynamics · Physics 2022-07-29 Runze Li , Yufei Zhang , Haixin Chen

The reliability assessment of a machine learning model's prediction is an important quantity for the deployment in safety critical applications. Not only can it be used to detect novel sceneries, either as out-of-distribution or anomaly…

Machine Learning · Computer Science 2022-05-12 Steve Dias Da Cruz , Bertram Taetz , Thomas Stifter , Didier Stricker

Due to the growing amount of data from in-situ sensors in wastewater systems, it becomes necessary to automatically identify abnormal behaviours and ensure high data quality. This paper proposes an anomaly detection method based on a deep…

Signal Processing · Electrical Eng. & Systems 2020-03-09 Stefania Russo , Andy Disch , Frank Blumensaat , Kris Villez

We propose a model of quasar lifetimes in which observational quasar lifetimes and an intrinsic lifetime of rapid accretion are strongly distinguished by the physics of obscuration by surrounding gas and dust. Quasars are powered by gas…

Extremely variable quasars can also show strong changes in broad-line emission strength and are known as changing-look quasars (CLQs). To study the CLQ transition mechanism, we present a pilot sample of CLQs with X-ray observations in both…

State-space graphical models and the variational autoencoder framework provide a principled apparatus for learning dynamical systems from data. State-of-the-art probabilistic approaches are often able to scale to large problems at the cost…

Machine Learning · Statistics 2024-11-05 Matthew Dowling , Yuan Zhao , Il Memming Park

We investigate the spectro-photometric variability of quasars due to lensing of small mass substructure (from several tens to several hundreds solar masses). The aim of this paper is to explore the milli/microlensing influence on the flux…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Luka C . Popović , Sasa Simić

Variational autoencoders were proven successful in domains such as computer vision and speech processing. Their adoption for modeling user preferences is still unexplored, although recently it is starting to gain attention in the current…

Machine Learning · Computer Science 2018-11-27 Noveen Sachdeva , Giuseppe Manco , Ettore Ritacco , Vikram Pudi