Results 31 to 40 of about 2,120,250 (297)
A search for spectral variability in WR1 [PDF]
Symposium - International Astronomical Union, 1995 Preliminary results of spectroscopic monitoring of the WN5-B star WR1 (HD 4004) are presented, showing evidence for a 0d.775 period.
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On the typical spectral shape of an economic variable [PDF]
Applied Economics Letters, 2003 In a classic article, Granger (Econometrica 34, 1966) asserted that most economic time series measured in level have spectra that exhibit a smooth declining shape with considerable power at very low frequencies. There has been no systematic attempt to examine Granger's assertion with international data.
Levy, Daniel, Dezhbakhsh, Hashem
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The MEXSAS2 Sample and the Ensemble X-ray Variability of Quasars
Frontiers in Astronomy and Space Sciences, 2017 We present the second Multi-Epoch X-ray Serendipitous AGN Sample (MEXSAS2), extracted from the 6th release of the XMM Serendipitous Source Catalog (XMMSSC-DR6), cross-matched with Sloan Digital Sky Survey quasar Catalogs DR7Q and DR12Q.
Roberto Serafinelli +4 more
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Spectral variability of IL cephei
Astrophysical Bulletin, 2013 The results of six years of spectroscopic studies of the Herbig Be star IL Cep (HD216629) are reported. Various spectral parameters of the Hα and Hβ emission lines and those of the He I λ 5876 A absorption feature are found for the first time to have exhibited slow variations in 2006–2011 and to have reached their extrema in 2009–2010.
Ismailov, N. Z. +3 more
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Variability and spectral variation of 3C 66A [PDF]
Astrophysics and Space Science, 2011 3C 66A was monitored by the BATC(Beijing-Arizona-Taipei-Connecticut) telescope from 2005 to 2008,1994 observations were obtained on 89 nights. Detailed research and analysis was performed on these observations in this paper. A long term burst occurred in the whole light curve.
Hu, Shao Ming +5 more
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Remote Sensing, 2023 Target detection is an important area in the applications of hyperspectral remote sensing. Due to the full use of information of the target and background, target detection algorithms based on the statistical characteristics of an image are always occupy
Luyan Ji, Xiurui Geng
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REMARKABLE SPECTRAL VARIABILITY OF PDS 456 [PDF]
The Astrophysical Journal, 2010 We report on the highest to date signal-to-noise-ratio X-ray spectrum of the luminous quasar PDS 456, as obtained during two XMM-Newton orbits in September 2007. The present spectrum is considerably different from several previous X-ray spectra recorded for PDS 456 since 1998.
Behar, E +5 more
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A Multi-Attention Autoencoder for Hyperspectral Unmixing Based on the Extended Linear Mixing Model
Remote Sensing, 2023 Hyperspectral unmixing, which decomposes mixed pixels into the endmembers and corresponding abundances, is an important image process for the further application of hyperspectral images (HSIs).
Lijuan Su, Jun Liu, Yan Yuan, Qiyue Chen
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Augmented GBM Nonlinear Model to Address Spectral Variability for Hyperspectral Unmixing
Remote Sensing, 2023 Spectral unmixing (SU) is a significant preprocessing task for handling hyperspectral images (HSI), but its process is affected by nonlinearity and spectral variability (SV). Currently, SV is considered within the framework of linear mixing models (LMM),
Linghong Meng +5 more
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Remote Sensing, 2023 Genetic variation among populations within plant species can have huge impact on canopy biochemistry and structure across broad spatial scales. Since canopy spectral reflectance is determined largely by canopy biochemistry and structure, spectral ...
Jingxue Zhang +9 more
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