English
Related papers

Related papers: Imaging VLBI polarimetry data from Active Galactic…

200 papers

Recently, learned image compression has achieved remarkable performance. The entropy model, which estimates the distribution of the latent representation, plays a crucial role in boosting rate-distortion performance. However, most entropy…

Image and Video Processing · Electrical Eng. & Systems 2024-09-16 Wei Jiang , Jiayu Yang , Yongqi Zhai , Peirong Ning , Feng Gao , Ronggang Wang

Exploration is essential for solving complex Reinforcement Learning (RL) tasks. Maximum State-Visitation Entropy (MSVE) formulates the exploration problem as a well-defined policy optimization problem whose solution aims at visiting all…

We develop a new methodology for model-based clustering. Optimizing the log-likelihood provides a principled statistical framework for clustering, with solutions found via the EM algorithm. However, because the log-likelihood is nonconvex,…

Methodology · Statistics 2026-05-06 Gonzalo Mena

Imaging relativistic jets in active galactic nuclei (AGN) at angular resolution significantly surpassing that of the ground-based VLBI at centimetre wavelengths is one of the key science objectives of the RadioAstron space-VLBI mission.…

Astrophysics of Galaxies · Physics 2020-01-10 Gabriele Bruni , Tuomas Savolainen , Jose Luis Gómez , Andrei P. Lobanov , Yuri Y. Kovalev

The Atacama Large mm-submm Array (ALMA) is, by far, the most sensitive mm/submm telescope in the World. The ALMA Phasing Project (APP) will allow us to phase-up all the ALMA antennas and use them as one single VLBI station. This will be a…

Instrumentation and Methods for Astrophysics · Physics 2015-04-27 I. Marti-Vidal , A. Roy , W. Alef , J. Conway , M. Lindqvist , A. J. Zensus

The celebrated CLEAN algorithm has been the cornerstone of deconvolution algorithms in radio interferometry almost since its conception in the 1970s. For all its faults, CLEAN is remarkably fast, robust to calibration artefacts and in its…

Instrumentation and Methods for Astrophysics · Physics 2021-01-21 Hertzog L. Bester , Audrey Repetti , Simon Perkins , Oleg M. Smirnov , Jonathan S. Kenyon

The EM (Expectation-Maximization) algorithm is regarded as an MM (Majorization-Minimization) algorithm for maximum likelihood estimation of statistical models. Expanding this view, this paper demonstrates that by choosing an appropriate…

Optimization and Control · Mathematics 2026-02-12 Kensuke Asai , Jun-ya Gotoh

The Atacama Large Millimeter/submillimeter Array (ALMA) is currently revolutionizing observational astrophysics. The aperture synthesis technique provides angular resolution otherwise unachievable with the conventional single-aperture…

Instrumentation and Methods for Astrophysics · Physics 2022-10-06 Łukasz Tychoniec , Fabrizia Guglielmetti , Philipp Arras , Torsten Enßlin , Eric Villard

Charts effectively convey quantitative information, but the underlying data are often locked in image form, hindering reuse and analysis. Manually digitizing charts is time-consuming and error-prone, motivating automatic chart-to-table…

Computation and Language · Computer Science 2026-05-27 Thomas Berkane , Qianyi Wang , Maimuna S. Majumder

We revisit the impact of finite time responses of bolometric detectors used for deep observations of the cosmic microwave background (CMB). Until now, bolometer transfer functions have been accounted for through a two-step procedure by…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-21 A. Basyrov , N. O. Stutzer , J. G. S. Lunde , H. K. Eriksen , E. Gjerløw , D. J. Watts , I. K. Wehus

Based on realistic simulations, we propose an hybrid method to reconstruct the lensing potential power spectrum, directly on PLANCK-like CMB frequency maps. It implies using a large galactic mask and dealing with a strong inhomogeneous…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 S. Plaszczynski , A. Lavabre , L. Perotto , J. -L. Starck

The expectation--maximization (EM) algorithm combines global monotonicity, local linear convergence, and strong practical robustness, but these features are usually analyzed separately. Global descent is nonlinear, whereas local convergence…

Machine Learning · Statistics 2026-05-11 Qiao Wang

This paper studies a multiuser mobile edge computing (MEC) system, in which one base station (BS) serves multiple users with intensive computation tasks. We exploit the multi-antenna non-orthogonal multiple access (NOMA) technique for…

Information Theory · Computer Science 2018-09-11 Feng Wang , Jie Xu , Zhiguo Ding

In this paper, a mode decomposition (MD) method for degenerated modes has been studied. Convolution neural network (CNN) has been applied for image training and predicting the mode coefficients. Four-fold degenerated $LP_{11}$ series has…

Computer Vision and Pattern Recognition · Computer Science 2022-07-13 Hyuntai Kim

Quantifying image distortions caused by strong gravitational lensing and estimating the corresponding matter distribution in lensing galaxies has been primarily performed by maximum likelihood modeling of observations. This is typically a…

Instrumentation and Methods for Astrophysics · Physics 2017-09-20 Yashar D. Hezaveh , Laurence Perreault Levasseur , Philip J. Marshall

Maximum entropy modeling is a flexible and popular framework for formulating statistical models given partial knowledge. In this paper, rather than the traditional method of optimizing over the continuous density directly, we learn a smooth…

Methodology · Statistics 2017-05-01 Gabriel Loaiza-Ganem , Yuanjun Gao , John P. Cunningham

Finding better solutions to combinatorial optimization problems could have a large positive impact on many real-world application areas, such as logistics. For this reason, significant efforts have been made to design novel optimisation…

A non iterative direct blind deconvolution procedure, previously used successfully to sharpen Hubble Space Telescope imagery, is now found useful in sharpening nanoscale scanning electron microscope (SEM) and helium ion microscope (HIM)…

Instrumentation and Detectors · Physics 2025-02-28 Alfred S. Carasso , Andras E. Vladar

Cross-View Geo-Localization (CVGL) involves determining the localization of drone images by retrieving the most similar GPS-tagged satellite images. However, the imaging gaps between platforms are often significant and the variations in…

Computer Vision and Pattern Recognition · Computer Science 2025-05-27 Zhongwei Chen , Zhao-Xu Yang , Hai-Jun Rong

VLBI observations of relativistic outflows (jets) in galactic nuclei, complemented with detailed studies made in other spectral domains, have become an effective tool for investigating the physics of nuclear regions in galaxies.…

Astrophysics · Physics 2007-09-03 Andrei Lobanov