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Three-dimensional wide-field galaxy surveys are fundamental for cosmological studies. For higher redshifts (z > 1.0), where galaxies are too faint, quasars still trace the large-scale structure of the Universe. Since available telescope…

Instrumentation and Methods for Astrophysics · Physics 2022-09-21 Sándor Kunsági-Máté , Róbert Beck , István Szapudi , István Csabai

We introduce QuasarNET, a deep convolutional neural network that performs classification and redshift estimation of astrophysical spectra with human-expert accuracy. We pose these two tasks as a \emph{feature detection} problem: presence or…

Instrumentation and Methods for Astrophysics · Physics 2018-08-31 Nicolas Busca , Christophe Balland

We present a catalogue of absorption lines obtained from the analysis of the ultra-violet spectra of 66 quasars. The data were acquired with the Faint Object Spectrograph of the HST as part of the Quasar Absorption Line Survey, a Key…

Collaborative path planning for robot swarms in complex, unknown environments without external positioning is a challenging problem. This requires robots to find safe directions based on real-time environmental observations, and to…

Robotics · Computer Science 2025-01-03 Chenxi Li , Weining Lu , Zhihao Ma , Litong Meng , Bin Liang

Efficiently modeling spatio-temporal (ST) physical processes and observations presents a challenging problem for the deep learning community. Many recent studies have concentrated on meticulously reconciling various advantages, leading to…

Artificial Intelligence · Computer Science 2024-06-04 Hao Wu , Yuxuan Liang , Wei Xiong , Zhengyang Zhou , Wei Huang , Shilong Wang , Kun Wang

Modeling quasar spectra is a fundamental task in astrophysics as quasars are the tell-tale sign of cosmic evolution. We introduce a novel unsupervised learning algorithm, Quasar Factor Analysis (QFA), for recovering the intrinsic quasar…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-07 Zechang Sun , Yuan-Sen Ting , Zheng Cai

I present the Automated Line Fitting Algorithm, ALFA, a new code which can fit emission line spectra of arbitrary wavelength coverage and resolution, fully automatically. In contrast to traditional emission line fitting methods which…

Solar and Stellar Astrophysics · Physics 2016-01-20 Roger Wesson

In ultrasound nondestructive testing, a widespread approach is to take synthetic aperture measurements from the surface of a specimen to detect and locate defects within it. Based on these measurements, imaging is usually performed using…

Signal Processing · Electrical Eng. & Systems 2020-12-09 Jan Kirchhof , Sebastian Semper , Christoph W. Wagner , Eduardo Pérez , Florian Römer , Giovanni Del Galdo

Remote Sensing (RS) is a crucial technology for observing, monitoring, and interpreting our planet, with broad applications across geoscience, economics, humanitarian fields, etc. While artificial intelligence (AI), particularly deep…

Computer Vision and Pattern Recognition · Computer Science 2025-06-04 Aoran Xiao , Weihao Xuan , Junjue Wang , Jiaxing Huang , Dacheng Tao , Shijian Lu , Naoto Yokoya

In this paper, we seek to develop a versatile test-time adaptation (TTA) objective for a variety of tasks - classification and regression across image-, object-, and pixel-level predictions. We achieve this through a self-bootstrapping…

Computer Vision and Pattern Recognition · Computer Science 2025-04-14 Shuaicheng Niu , Guohao Chen , Peilin Zhao , Tianyi Wang , Pengcheng Wu , Zhiqi Shen

This study proposes an anomaly detection method based on the Transformer architecture with integrated multiscale feature perception, aiming to address the limitations of temporal modeling and scale-aware feature representation in cloud…

Machine Learning · Computer Science 2025-08-26 Lian Lian , Yilin Li , Song Han , Renzi Meng , Sibo Wang , Ming Wang

A statistical analysis of the space-time distribution of absorption-line systems (ALSs) observed in QSO spectra within the cosmological redshift interval $z$=0.0--3.7 is carried out on the base of our catalog of absorption systems…

Astrophysics · Physics 2008-11-26 A. I. Ryabinkov , A. D. Kaminker , D. A. Varshalovich

Artificial Intelligence (AI) has become an exceptionally powerful tool for analyzing scientific data. In particular, attention-based architectures have demonstrated a remarkable capability to capture complex correlations and to furnish…

Strongly Correlated Electrons · Physics 2025-11-03 Changkai Zhang , Jan von Delft

We describe initial results of a search for redshifted molecular absorption toward four millimetre-loud, optically faint quasars. A wide frequency bandwidth of up to 23 GHz per quasar was scanned using the Swedish-ESO Sub-millimetre…

Astrophysics · Physics 2009-11-07 M. T. Murphy , S. J. Curran , J. K. Webb

This work introduces a new framework, named SAFFIRE, to automatically extract a dominant recurrent image pattern from a set of image samples. Such a pattern shall be used to eliminate pose variations between samples, which is a common…

Computer Vision and Pattern Recognition · Computer Science 2021-03-08 Marco Boschi , Luigi Di Stefano , Martino Alessandrini

Large statistical samples of quasar spectra have previously indicated possible cosmological variations in the fine-structure constant, $\alpha$. A smaller sample of higher signal-to-noise ratio spectra, with dedicated calibration, would…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 T. M. Evans , M. T. Murphy , J. B. Whitmore , T. Misawa , M. Centurion , S. D'Odorico , S. Lopez , C. J. A. P. Martins , P. Molaro , P. Petitjean , H. Rahmani , R. Srianand , M. Wendt

Solving tough clinical questions that require both image and text understanding is still a major challenge in healthcare AI. In this work, we propose Q-FSRU, a new model that combines Frequency Spectrum Representation and Fusion (FSRU) with…

Computer Vision and Pattern Recognition · Computer Science 2025-08-19 Rakesh Thakur , Yusra Tariq

At high redshift, due to both observational limitations and the variety of galaxy morphologies in the early universe, measuring galaxy structure can be challenging. Non-parametric measurements such as the CAS system have thus become an…

Astrophysics of Galaxies · Physics 2021-09-08 C. Tohill , L. Ferreira , C. J. Conselice , S. P. Bamford , F. Ferrari

Presented is a novel way to combine snapshot compressive imaging and lateral shearing interferometry in order to capture the spatio-spectral phase of an ultrashort laser pulse in a single shot. A deep unrolling algorithm is utilised for the…

After 40 years we have no "low" theory of quasars to predict the atomic absorption and emission features so abundant in quasar spectra. Here I take the first step, using results selected for their diagnostic power to build an "observational…

Astrophysics · Physics 2007-05-23 Martin Elvis
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