Results 1 to 10 of about 155 (152)
Statistical Classification Techniques for Photometric Supernova Typing [PDF]
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2010 Future photometric supernova surveys will produce vastly more candidates than can be followed up spectroscopically, highlighting the need for effective classification methods based on lightcurves alone. Here we introduce boosting and kernel density estimation techniques which have minimal astrophysical input, and compare their performance on 20,000 ...
Newling, James +10 more
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Luminosity Functions From Photometric Redshifts. I. Techniques [PDF]
The Astronomical Journal, 1996 The determination of the galaxy luminosity function is an active and fundamental field in observational cosmology. In this paper we propose a cost effective way of measuring galaxy luminosity functions at faint magnitudes. Our technique employs the use of galaxy redshifts estimated from their multicolor photometry (Connolly et al. 1995).
SubbaRao, M. U. +3 more
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Photometric Redshift Techniques in Big-data Era [PDF]
Proceedings of the International Astronomical Union, 2015 AbstractPhotometric data increase with large survey projects running. The huge volume of data influences the means and methods to deal with them. As such, the techniques of photometric redshift estimation based on photometric data must be developed and improved.
Yan-Xia Zhang, Yong-Heng Zhao
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Error analysis of the photometric redshift technique [PDF]
Monthly Notices of the Royal Astronomical Society, 2002 We present a calculation of the systematic component of the error budget in the photometric redshift technique. We make use of it to describe a simple technique that allows for the assignation of confidence limits to redshift measurements obtained through photometric methods. We show that our technique, through the calculation of a redshift probability
Fernandez-Soto, A. +4 more
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Generalisation of Photometric Stereo technique to Q-illuminants [PDF]
Procedings of the British Machine Vision Conference 2008, 2008 We present a generalisation of the 4-light photometric stereo technique to an arbitrary number Q of illuminants. We assume that the surface reflectance can be approximated by the Lambertian model plus a reflectance component. The algorithm works in a recursive manner eliminating the pixel intensities affected by shadows or highlights based on a least ...
V. Argyriou, S. Barsky, M. Petrou
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Optical design of photometric techniques for specular reflection
Optics and Lasers in Engineering, 2022 Abstract Photometric techniques are one of the three-dimensional image reconstruction technologies. It is used in various fields, especially surface analysis because it focuses on extracting surface information such as texture and color. Photometric techniques perform the 3D reconstruction using light sources and a camera.
Hanjin Cho, Siwoo Lee, Byoungho Lee
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A Modified Photometric Technique for Measuring Sebum Excretion Rate
Journal of Investigative Dermatology, 1980 Accurate measurement of sebum excretion is necessary to evaluate drugs such as anti-androgen and the new retinoic acid derivatives. Existing techniques are good, but some are inaccurate at high levels of sebum and are time-consuming for technicians. We have therefore, re-examined sebum excretion methodology and have developed a modified photometric ...
Cunliffe, William James +2 more
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Stereo-photometric techniques for scanning micrometer scale
Virtual Archaeology Review, 2015 This paper describes a new methodology based on the combination of photogrammetric and stereo-photometric techniques that allows creating virtual replicas reproducing the relief in micrometric scale, with a geometric resolution until 7 microns. The finest details of the texture obtained by photogrammetric methods are translated to the relief of the ...
Rocio Cachero, Carlota Abello
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Photometric Classification of QSOs with Machine Learning Techniques
, 2022 With the advent of wide-area photometric surveys and the large amount of available data, the use of machine learning techniques is becoming more and more frequent to classify stars, galaxies and QSOs. In this work we investigate the performance of random forest in classifying QSOs using photometry of the 20 contiguous, equal-width, -nonoverlapping ...
Sánchez, Néstor +4 more
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A Comparison of Photometric Redshift Techniques for Large Radio Surveys [PDF]
Publications of the Astronomical Society of the Pacific, 2019 Future radio surveys will generate catalogues of tens of millions of radio sources, for which redshift estimates will be essential to achieve many of the science goals. However, spectroscopic data will be available for only a small fraction of these sources, and in most cases even the optical and infrared photometry will be of limited quality ...
Ray P. Norris +16 more
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