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Author Kocifaj, M.; Wallner, S.; Solano-Lamphar, H.A.
Title (up) An asymptotic formula for skyglow modelling over a large territory Type Journal Article
Year 2019 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal
Volume 485 Issue 2 Pages 2214-2224
Keywords Skyglow
Abstract An analytical framework to predict skyglow due to distant sources is presented, which can be applied to model sky brightness from the zenith toward the horizon along a vertical plane crossing the hemisphere in the azimuthal position of a light source. Although various powerful algorithms have been developed over the last few decades, the time needed for calculation grows exponentially with increasing size of the modelling domain. This is one of the key issues in skyglow computations, because the numerical accuracy improves only slowly as the modelling domain extends. We treat the problem theoretically, by introducing an analytical formula that is well-suited for light sources located at intermediate and long distances from an observation point and allows tremendous time savings in numerical analyses, while keeping the error at a low level. Field experiments carried out in Eastern Austria provided a unique opportunity to validate the model using real-sky luminance data. The fact that the theoretical model allows the prediction of sky luminance within an acceptable error tolerance is not only in line with the experimental data, but also provides new means of remote characterization of light emissions from artificial sources. The method is particularly attractive for rapid and simple retrieval of the amount of light escaping upwards from the dominant light sources surrounding the observation point. We expect that the method can advance the numerical modelling of skyglow substantially, because it allows real-time computations for very large territories.
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ISSN 0035-8711 ISBN Medium
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Notes Approved no
Call Number GFZ @ kyba @ Serial 2258
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Author Noll, S.; Kausch, W.; Barden, M.; Jones, A.M.; Szyszka, C.; Kimeswenger, S.; Vinther, J.
Title (up) An atmospheric radiation model for Cerro Paranal: I. The optical spectral range* Type Journal Article
Year 2012 Publication Astronomy & Astrophysics Abbreviated Journal A&A
Volume 543 Issue Pages A92
Keywords atmospheric effects; site testing; radiative transfer; radiation mechanisms: general; scattering; techniques; spectroscopic; modeling; observatories; Cerro Paranal
Abstract Aims. The Earth’s atmosphere affects ground-based astronomical observations. Scattering, absorption, and radiation processes deteriorate the signal-to-noise ratio of the data received. For scheduling astronomical observations it is, therefore, important to accurately estimate the wavelength-dependent effect of the Earth’s atmosphere on the observed flux.

Methods. In order to increase the accuracy of the exposure time calculator of the European Southern Observatory’s (ESO) Very Large Telescope (VLT) at Cerro Paranal, an atmospheric model was developed as part of the Austrian ESO In-Kind contribution. It includes all relevant components, such as scattered moonlight, scattered starlight, zodiacal light, atmospheric thermal radiation and absorption, and non-thermal airglow emission. This paper focuses on atmospheric scattering processes that mostly affect the blue (<0.55&#8201;&#956;m) wavelength regime, and airglow emission lines and continuum that dominate the red (>0.55&#8201;&#956;m) wavelength regime. While the former is mainly investigated by means of radiative transfer models, the intensity and variability of the latter is studied with a sample of 1186 VLT FORS&#8201;1 spectra.

Results. For a set of parameters such as the object altitude angle, Moon-object angular distance, ecliptic latitude, bimonthly period, and solar radio flux, our model predicts atmospheric radiation and transmission at a requested resolution. A comparison of our model with the FORS&#8201;1 spectra and photometric data for the night-sky brightness from the literature, suggest a model accuracy of about 20%. This is a significant improvement with respect to existing predictive atmospheric models for astronomical exposure time calculators.
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Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-6361 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 274
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Author Elejoste, P.; Angulo, I.; Perallos, A.; Chertudi, A.; Zuazola, I.J.G.; Moreno, A.; Azpilicueta, L.; Astrain, J.J.; Falcone, F.; Villadangos, J.
Title (up) An easy to deploy street light control system based on wireless communication and LED technology Type Journal Article
Year 2013 Publication Sensors (Basel, Switzerland) Abbreviated Journal Sensors (Basel)
Volume 13 Issue 5 Pages 6492-6523
Keywords Lighting
Abstract This paper presents an intelligent streetlight management system based on LED lamps, designed to facilitate its deployment in existing facilities. The proposed approach, which is based on wireless communication technologies, will minimize the cost of investment of traditional wired systems, which always need civil engineering for burying of cable underground and consequently are more expensive than if the connection of the different nodes is made over the air. The deployed solution will be aware of their surrounding's environmental conditions, a fact that will be approached for the system intelligence in order to learn, and later, apply dynamic rules. The knowledge of real time illumination needs, in terms of instant use of the street in which it is installed, will also feed our system, with the objective of providing tangible solutions to reduce energy consumption according to the contextual needs, an exact calculation of energy consumption and reliable mechanisms for preventive maintenance of facilities.
Address Deusto Institute of Technology (DeustoTech), University of Deusto, Bilbao 48007, Spain. perallos@deusto.es
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Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1424-8220 ISBN Medium
Area Expedition Conference
Notes PMID:23681092; PMCID:PMC3690067 Approved no
Call Number LoNNe @ kagoburian @ Serial 631
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Author Jørgensen, L. D., Tambo, T., & Xydis, G.
Title (up) An efficiency evaluation of radar‐based obstruction lights controlling at a wind turbine test site Type Journal Article
Year 2019 Publication Wind Energy Abbreviated Journal
Volume 22 Issue 4 Pages
Keywords Lighting; Public Safety; Planning
Abstract In this study, an obstruction lights controlling (OLC) system based on a Terma SCANTER 5000 radar has been installed at a test centre for large wind turbines. The objective of this study was to evaluate the efficiency of the OLC system and to improve this efficiency by introducing new technological features. Once the first assessment had been carried out, new software with improved tracking functionalities was installed to the radar. With the new software, a second assessment was made to compare the new performance to the old one. To analyse the tracks, geographic information system (GIS) tools have been used. A new MATLAB script was developed to automate the assessment as well as to gather data on the tracks. These data sets were used to improve the system performance by introducing a radar cross section (RCS)/speed filter. The outcome of the study is a filter that can be implemented on the radar system to improve the efficiency of the system and reduce the time that obstruction lights need to be on for by 62.59%, without compromising the integrity of the system.
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Notes Approved no
Call Number IDA @ intern @ Serial 2298
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Author Votsi, N.-E.P.; Kallimanis, A.S.; Pantis, I.D.
Title (up) An environmental index of noise and light pollution at EU by spatial correlation of quiet and unlit areas Type Journal Article
Year 2017 Publication Environmental Pollution (Barking, Essex : 1987) Abbreviated Journal Environ Pollut
Volume 221 Issue Pages 459-469
Keywords Remote Sensing
Abstract Quietness exists in places without human induced noise sources and could offer multiple benefits to citizens. Unlit areas are sites free of human intense interference at night time. The aim of this research is to develop an integrated environmental index of noise and light pollution. In order to achieve this goal the spatial pattern of quietness and darkness of Europe was identified, as well as their overlap. The environmental index revealed that the spatial patterns of Quiet and Unlit Areas differ to a great extent highlighting the importance of preserving quietness as well as darkness in EU. The spatial overlap of these two environmental characteristics covers 32.06% of EU surface area, which could be considered a feasible threshold for protection. This diurnal and nocturnal metric of environmental quality accompanied with all direct and indirect benefits to human well-being could indicate a target for environmental protection in the EU policy and practices.
Address Department of Ecology, School of Biology, Aristotle University, 54124, U.P. Box 119, Thessaloniki, Greece
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Language English Summary Language Original Title
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Series Volume Series Issue Edition
ISSN 0269-7491 ISBN Medium
Area Expedition Conference
Notes PMID:27989389 Approved no
Call Number LoNNe @ kyba @ Serial 1662
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