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Author Solano Lamphar, H.A.; Kocifaj, M. url  doi
openurl 
  Title Urban night-sky luminance due to different cloud types: A numerical experiment Type Journal Article
  Year 2015 Publication Lighting Research and Technology Abbreviated Journal Lighting Res. & Tech.  
  Volume 48 Issue 8 Pages 1017-1033  
  Keywords Skyglow; modeling; urban; clouds; radiative transfer  
  Abstract In this paper, we analyse theoretically and numerically the sky glow in urban and suburban areas, focusing on the zenith-normalised luminance of a cloudy sky. The results suggest that the altitude of a cloud imposes important changes in the luminance distribution. Peak values of sky luminance can be observed at a distance d = R + h tan (z), where R is the city radius, and h is the cloud altitude. Fluctuations of the zenith-normalised luminance over the city are dictated by three effects, specifically (i) extinction and backscatter in the undercloud atmosphere, (ii) the cloud properties and (iii) the radiant intensity function of the dominant ground-based light sources. For high clouds, the aerosol optical property is evident at moderate elevation angles. The light beams emitted from different parts of the city propagate along different inclined trajectories before they contribute to the elevated zenith luminance of low clouds. Then, multiple factors combine together to form the light field at the ground, city-size and city emission pattern being of specific importance.  
  Address Cátedras CONACYT, Instituto de investigaciones Dr José María Luis Mora, Programa Interdisciplinario de Estudios Metropolitanos (CentroMet), Plaza Valentín Gómez Farías #12 Col. San Juan Mixcoac, México D.F. C.P 03730. E-mail: lamphar(at)gmail.com  
  Corporate Author Thesis  
  Publisher (down) SAGE Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1477-0938 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1225  
Permanent link to this record
 

 
Author Escofet, J.; Bará, S. url  doi
openurl 
  Title Reducing the circadian input from self-luminous devices using hardware filters and software applications Type Journal Article
  Year 2015 Publication Lighting Research and Technology Abbreviated Journal Lighting Res. & Tech.  
  Volume 49 Issue 4 Pages 481-496  
  Keywords Lighting; devices; circadian disruption; screens; self-luminous  
  Abstract The widespread use of self-luminous devices at nighttime (cell-phones, computers, and tablets) raises some reasonable concerns regarding their effects on human physiology. Light at night is a known circadian disruptor, particularly at short visible wavelengths, and it seems advisable to have practical tools for tailoring the spectral radiance of these displays. We analyse two possible strategies to achieve this goal, using hardware filters or software applications. Overall, software applications seem to offer, at the present time, the best trade-offs for controlling the light spectra emitted by existing devices. We submit that such tools should be included as a standard feature on any self-luminous device and that their default settings should be established according to the best available knowledge on the circadian effects of light.  
  Address Departament d'Ã’ptica i Optometria, Universitat Politècnica de Catalunya, Terrassa, Catalunya, Spain; salva.bara(at)usc.es  
  Corporate Author Thesis  
  Publisher (down) SAGE Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1477-1535 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1315  
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Author Rodríguez Martín, A.; Chiaradia, A.; Wasiak, P.; Renwick, L.; Dann, P. url  doi
openurl 
  Title Waddling on the Dark Side: Ambient Light Affects Attendance Behavior of Little Penguins Type Journal Article
  Year 2016 Publication Journal of Biological Rhythms Abbreviated Journal J Biol Rhythms  
  Volume 0748730415626010 Issue Pages  
  Keywords Animals; birds; penguins; attendance; little penguin; Eudyptula minor; Phillip Island; Australia; photobiology; seabirds  
  Abstract Visible light on Earth largely comes from the sun, including light reflected from the moon. Predation risk is strongly determined by light conditions, and some animals are nocturnal to reduce predation. Artificial lights and its consequent light pollution may disrupt this natural behavior. Here, we used 13 years of attendance data to study the effects of sun, moon, and artificial light on the attendance pattern of a nocturnal seabird, the little penguin Eudyptula minor at Phillip Island, Australia. The little penguin is the smallest and the only penguin species whose activity on land is strictly nocturnal. Automated monitoring systems recorded individually marked penguins every time they arrived (after sunset) at or departed (before sunrise) from 2 colonies under different lighting conditions: natural night skylight and artificial lights (around 3 lux) used to enhance penguin viewing for ecotourism around sunset. Sunlight had a strong effect on attendance as penguins arrived on average around 81 min after sunset and departed around 92 min before sunrise. The effect of moonlight was also strong, varying according to moon phase. Fewer penguins came ashore during full moon nights. Moon phase effect was stronger on departure than arrival times. Thus, during nights between full moon and last quarter, arrival times (after sunset) were delayed, even though moonlight levels were low, while departure times (before sunrise) were earlier, coinciding with high moonlight levels. Cyclic patterns of moon effect were slightly out of phase but significantly between 2 colonies, which could be due to site-specific differences or presence/absence of artificial lights. Moonlight could be overridden by artificial light at our artificially lit colony, but the similar amplitude of attendance patterns between colonies suggests that artificial light did not mask the moonlight effect. Further research is indeed necessary to understand how seabirds respond to the increasing artificial night light levels.  
  Address Department of Evolutionary Ecology, Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas, Avda. Américo Vespucio s/n, 41092 Seville, Spain; airamrguez(at)ebd.csic.es  
  Corporate Author Thesis  
  Publisher (down) SAGE Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0748-7304 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1345  
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Author Nasar, J.L.; Bokharaei, S. url  doi
openurl 
  Title Impressions of Lighting in Public Squares After Dark Type Journal Article
  Year 2017 Publication Environment & Behavior Abbreviated Journal Env. & Behav.  
  Volume 43 Issue 3 Pages 227-254  
  Keywords Psychology; public lighting; public safety; security; crime; perception; outdoor lighting  
  Abstract Lighting may affect impressions of public squares. Following studies on office interior lighting, the present research manipulated three modes of lighting—non-uniform–uniform, peripheral–overhead, and dim–bright—in three virtual squares. One study had 32 participants (15 men, 17 women) judge the spaciousness and privacy of each of the 24 public squares. A second study had a different group of 30 participants (16 men, 14 women) rate the appeal, safety from crime, and excitement of each square. Study 1 found that judged spaciousness increased with uniform and bright lighting, and that privacy increased with non-uniform, dim, and peripheral lighting. Study 2 found that rated appeal increased with uniform and bright lighting, as did safety from crime and excitement. Across the two studies, the uniform and bright lighting conditions contributed most to the kinds of favorable experiences people might expect to have in public spaces after dark.  
  Address City & Regional Planning, Ohio State University, 200 Knowlton Hall 275 W Woodruff Ave., Columbus, OH 43210, USA. Email: nasar.1(at)osu.edu  
  Corporate Author Thesis  
  Publisher (down) SAGE Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0013-9165 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1390  
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Author Bará, S.; Rodríguez-Arós, Á.; Pérez, M.; Tosar, B.; Lima, R.; Sánchez de Miguel, A.; Zamorano, J. url  doi
openurl 
  Title Estimating the relative contribution of streetlights, vehicles, and residential lighting to the urban night sky brightness Type Journal Article
  Year 2018 Publication Lighting Research & Technology Abbreviated Journal Lighting Res & Tech  
  Volume Issue October 2018 Pages  
  Keywords Remote Sensing; traffic; Roadway lighting  
  Abstract Under stable atmospheric conditions the brightness of the urban sky varies throughout the night following the time course of the anthropogenic emissions of light. Different types of artificial light sources (e.g. streetlights, residential, and vehicle lights) have specific time signatures, and this feature makes it possible to estimate the amount of brightness contributed by each of them. Our approach is based on transforming the time representation of the zenithal night sky brightness into a modal expansion in terms of the time signatures of the different sources of light. The modal coefficients, and hence the absolute and relative contributions of each type of source, can be estimated by means of a linear least squares fit. A practical method for determining the time signatures of different contributing sources is also described, based on wide-field time-lapse photometry of the urban nightscape. Our preliminary results suggest that, besides the dominant streetlight contribution, artificial light leaking out of the windows of residential buildings may account for a significant share of the time-varying part of the zenithal night sky brightness at the measurement locations, whilst the contribution of the vehicle lights seems to be significantly smaller.  
  Address Área de Óptica, Dept. Física Aplicada, Facultade de Óptica e Optometría, Universidade de Santiago de Compostela, Santiago de Compostela 15782, Galicia, Spain. salva.bara(at)usc.es  
  Corporate Author Thesis  
  Publisher (down) SAGE Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1477-1535 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2052  
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