19,784 research outputs found
Time-Series Surveys and Pulsating Stars: The Near-Infrared Perspective
The purpose of this review is to discuss the advantages and problems of
near-infrared surveys in observing pulsating stars in the Milky Way. One of the
advantages of near-infrared surveys, when compared to optical counterparts, is
that the interstellar extinction is significantly smaller. As we see in this
review, a significant volume of the Galactic disk can be reached by infrared
surveys but not by optical ones. Towards highly obscured regions in the
Galactic mid-plane, however, the interstellar extinction causes serious
problems even with near-infrared data in understanding the observational
results. After a review on previous and current near-infrared surveys, we
discuss the effects of the interstellar extinction in optical (including {\it
Gaia}) to near-infrared broad bands based on a simple calculation using
synthetic spectral energy distribution. We then review the recent results on
classical Cepheids towards the Galactic center and the bulge, as a case study,
to see the impact of the uncertainty in the extinction law. The extinction law,
i.e. the wavelength dependency of the extinction, is not fully characterized,
and its uncertainty makes it hard to make the correction. Its characterization
is an urgent task in order to exploit the outcomes of ongoing large-scale
surveys of pulsating stars, e.g. for drawing a map of pulsating stars across
the Galactic disk.Comment: Conference on wide field variability surveys: a 21st-century
perspective, 8 pages with 6 figures in pres
Notes on the Wess-Zumino-Witten-like structure: triplet and NS-NS superstring field theory
In the NS-NS sector of superstring field theory, there potentially exist
three nilpotent generators of gauge transformations and two constraint
equations: It makes the gauge algebra of type II theory somewhat complicated.
In this paper, we show that every NS-NS actions have their WZW-like forms, and
that a triplet of mutually commutative products completely
determines the gauge structure of NS-NS superstring field theory via its
WZW-like structure. We give detailed analysis about it and present its
characteristic properties by focusing on two NS-NS actions proposed by
arXiv:1512.03379 and arXiv:1403.0940.Comment: 23+3 pages; Published ve
Image processing for the extraction of nutritional information from food labels
Current techniques for tracking nutritional data require undesirable amounts of either time or man-power. People must choose between tediously recording and updating dietary information or depending on unreliable crowd-sourced or costly maintained databases. Our project looks to overcome these pitfalls by providing a programming interface for image analysis that will read and report the information present on a nutrition label directly. Our solution involves a C++ library that combines image pre-processing, optical character recognition, and post-processing techniques to pull the relevant information from an image of a nutrition label. We apply an understanding of a nutrition label\u27s content and data organization to approach the accuracy of traditional data-entry methods. Our system currently provides around 80% accuracy for most label images, and we will continue to work to improve our accuracy
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