Results 11 to 20 of about 13,459 (229)

Variational views for self-supervised learning in radio astronomy

RAS Techniques and Instruments
Abstract Modern astronomical surveys are producing progressively larger and more complex datasets, making traditional supervised approaches that rely on extensive labelled catalogues increasingly difficult. Consequently, pre-training using self-supervised learning (SSL), which offers a scalable route by extracting structure directly ...
Johnny Joseph Alphonse, Anna M M Scaife
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Report of combined meeting of Commissions 8 (Meridian Astronomy), 19 (Variation Of Latitude) and 31 (Time), August 21. 9.30 a.m [PDF]

Transactions of the International Astronomical Union, 1950
The President outlined the history of the Ross photographic zenith tube, saying that it was originally designed for measurement of the variation of latitude by Dr Ross, and later adapted to the determination of time by Dr Littel. The success of the instrument and its possible application to various problems in positional astronomy made it of interest ...
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Roche Model and Absolute Dimensions of the Eclipsing Binary Y Cam with a Pulsating Component [PDF]

Journal of Astronomy and Space Sciences, 2002
We performed CCD photometric observations of the eclipsing binary Y Cam with a pulsating component, for 16 nights from November 2000 to May 2001 using a V filter attached to the 61-cm reflector at Sobaeksan Optical Astronomy Observatory.
J. W. Lee, C. -H. Kim, S. -L. KIM, J. -H. Youn, S. -G. Kwon   +4 more
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Cepstrum Analysis of Terrestrial Impact Crater Records [PDF]

Journal of Astronomy and Space Sciences, 2008
Study of terrestrial impact craters is important not only in the field of the solar system formation and evolution but also of the Galactic astronomy. The terrestrial impact cratering record recently has been examined, providing short- and intermediate ...
Heon-Young Chang, Cheongho Han
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The Host Galaxy Fluxes of Active Galaxy Nuclei Are Generally Overestimated by the Flux Variation Gradient Method

Universe
In terms of the variable nature of normal active galaxy nuclei (AGN) and luminous quasars, a so-called flux variation gradient (FVG) method has been widely utilized to estimate the underlying non-variable host galaxy fluxes.
Minxuan Cai, Zhen Wan, Zhenyi Cai, Lulu Fan, Junxian Wang   +4 more
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Period Change of the Contact Binary AH Tauri [PDF]

Journal of Astronomy and Space Sciences, 2004
New BVRI photometric observations of the contact binary AH Tau were performed with the 61 cm reflector and a 2K CCD camera at the Sobaeksan Optical Astronomy Observatory during seven nights from September to December, 2001. A total of 144 times of minima
Dongjoo Lee, Chung-Uk Lee, Jae Woo Lee, Seung-Lee Kim, Kyu-Dong Oh, Chun-Hwey Kim   +5 more
doaj   +1 more source

“Frog-eyes” in astronomy: Monitoring binary radial velocity variations through a pair of narrow-band filters

Science China Physics, Mechanics & Astronomy
Spectroscopic observations are a crucial step in driving major discoveries in the era of time-domain surveys. However, the pace of current spectroscopic surveys is increasingly unable to meet the demands of rapidly advancing large-scale time-domain surveys.
Zheng, Chuanjie, Huang, Yang, Liu, Jifeng, Gu, Hongrui, Wu, Hong, Lu, Youjun, Sun, Yongkang, Han, Henggeng, Wang, Song, Beers, Timothy C., Xiao, Kai, Li, Zhirui, Zhang, Boweng, Mao, Yongna, Li, Zhengyang, Ji, Hangxin   +15 more
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The Illusory Precision of Transit Timing Variation Masses: Hidden Solutions Behind Kepler-9’s Tight Mass Ratio

The Astrophysical Journal
Transit timing variations (TTVs) are considered a tool for constraining the masses of transiting planets in the absence of radial velocity data. Although theoretical studies have long revealed that TTV mass determinations intrinsically suffer from ...
Sheng Jin, Dong-Hong Wu, Xiao-Ling Xu, Jianghui Ji   +3 more
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New Astronomical Observatory Design for the Detection and Tracking of Satellite Objects: The Satellite Robotic Observatory (SRO)

Remote Sensing
Robotic Astronomical Observatories (RAOs) have provided very good results in different research projects in astrophysics/astronomy. Their applications in the detection, tracking, and identification of near-Earth objects have contributed to the ...
Francisco Espartero, Javier Cubas, David Nespral, Santiago Pindado   +3 more
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PERIODIC AND SPORADIC VARIATIONS IN THE SPECTRAL FLUX DENSITY OF THE CAS A SUPERNOVA REMNANT [PDF]

Radio Physics and Radio Astronomy, 2020
Purpose: Based on the long-term study data in all radio spectrum ranges, the nature of deviations of spectral flux density of the Cas A supernova remnant from the tendency of its secular decrease is considered.
A. A. Gorbunov, M. I. Ryabov, A. L. Sukharev, V. V. Bezrukovs   +3 more
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