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Author Bará, S. url  doi
openurl 
  Title Naked-eye astronomy: optics of the starry night skies Type Journal Article
  Year 2014 Publication Proc. SPIE 9289, 12th Education and Training in Optics and Photonics Conference, 2014 Abbreviated Journal Proc. SPIE 9289  
  Volume 9289 Issue Pages  
  Keywords Society; light pollution  
  Abstract The world at night offers a wealth of stimuli and opportunities as a resource for Optics education, at all age levels and from any (formal, non formal or informal) perspective. The starry sky and the urban nightscape provide a unique combination of pointlike sources with extremely different emission spectra and brightness levels on a generally darker, locally homogeneous background. This fact, combined with the particular characteristics of the human visual system under mesopic and scotopic conditions, provides a perfect setting for experiencing first-hand different optical phenomena of increasing levels of complexity: from the eye's point spread function to the luminance contrast threshold for source detection, from basic diffraction patterns to the intricate irradiance fluctuations due to atmospheric turbulence. Looking at the nightscape is also a perfect occasion to raise awareness on the increasing levels of light pollution associated to the misuse of public and private artificial light at night, to promote a sustainable use of lighting, and to take part in worldwide citizen science campaigns. Last but not least, night sky observing activities can be planned and developed following a very flexible schedule, allowing individual students to carry them out from home and sharing the results in the classroom as well as organizing social events and night star parties with the active engagement of families and groups of the local community. This contribution describes these possibilities and introduces some of the free resources available to put them in practice.  
  Address Univ. de Santiago de Compostela, Spain; salva.bara@usc.es  
  Corporate Author Thesis  
  Publisher (down) SPIE Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1134  
Permanent link to this record
 

 
Author Bará, S. url  doi
openurl 
  Title Light pollution and solid-state lighting: reducing the carbon dioxide footprint is not enough Type Journal Article
  Year 2014 Publication Proc. SPIE 8785, 8th Iberoamerican Optics Meeting and 11th Latin American Meeting on Optics, Lasers, and Applications, 87852G, 2013 Abbreviated Journal Proc. SPIE 8785  
  Volume 8785 Issue Pages  
  Keywords *Lighting; LED; light emitting diode; outdoor lighting; artificial light at night; lighting policy; solid-state lighting; blue light  
  Abstract Public and private lighting account for a relevant share of the overall electric power consumption worldwide. The pressing need of reducing the carbon dioxide emissions as well as of lowering the lumen•hour price tag has fostered the search for alternative lighting technologies to substitute for the incandescent and gas-discharge based lamps. The most successful approach to date, solid-state lighting, is already finding its way into the public lighting market, very often helped by substantial public investments and support. LED-based sources have distinct advantages: under controlled conditions their efficacy equals or surpasses that of conventional solutions, their small source size allows for an efficient collimation of the lightbeam (delivering the photons where they are actually needed and reducing lightspill on the surrounding areas), and they can be switched and/or dimmed on demand at very high rates, thus allowing for a tailored schedule of lighting. However, energy savings and carbon dioxide reduction are not the only crucial issues faced by present day lighting. A growing body of research has shown the significance of the spectral composition of light when it comes to assess the detrimental effects of artificial light-at-night (ALAN). The potential ALAN blueshift associated to the deployment of LED-based lighting systems has raised sensible concerns about its scientific, cultural, ecological and public health consequences, which can be further amplified if an increased light consumption is produced due to the rebound effect. This contribution addresses some of the challenges that these issues pose to the Optics and Photonics community.  
  Address Univ. de Santiago de Compostela, Spain; salva.bara@usc.es  
  Corporate Author Thesis  
  Publisher (down) SPIE Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1135  
Permanent link to this record
 

 
Author Cinzano, P.; Falchi, F. url  openurl
  Title A portable wide-field instrument for mapping night sky brightness automatically Type Journal Article
  Year 2003 Publication Memorie della Società Astronomica Italiana Abbreviated Journal Mem. S.A. It.  
  Volume 74 Issue 2 Pages 458-459  
  Keywords Instrumentation; all-sky; photometry; sky brightness  
  Abstract We present a portable automatic instrument for monitoring night sky brightness and atmospherical transparency in astronomical photometrical bands. Main requirements were: fast and automatic coverage of the entire sky, lightness, transportability and quick set-up in order to take measurements from more sites in the same night, easily available commercial components and software to be reproduced by any interested institution, included amateurs astronomers groups.  
  Address Istituto di Scienza e Tecnologia dell’Inquinamento Luminoso, Thiene, Italy  
  Corporate Author Thesis  
  Publisher (down) Società Astronomica Italiana Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1824-016X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 2243  
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Author Kocifaj, M. url  doi
openurl 
  Title Towards a Comprehensive City Emission Function (CCEF) Type Journal Article
  Year 2018 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal JQSRT  
  Volume 205 Issue Pages 253-266  
  Keywords Lighting; Skyglow  
  Abstract The comprehensive city emission function (CCEF) is developed for a heterogeneous light-emitting or blocking urban environments, embracing any combination of input parameters that characterize linear dimensions in the system (size and distances between buildings or luminaires), properties of light-emitting elements (such as luminous building façades and street lighting), ground reflectance and total uplight-fraction, all of these defined for an arbitrarily sized 2D area. The analytical formula obtained is not restricted to a single model class as it can capture any specific light-emission feature for wide range of cities. The CCEF method is numerically fast in contrast to what can be expected of other probabilistic approaches that rely on repeated random sampling. Hence the present solution has great potential in light-pollution modeling and can be included in larger numerical models. Our theoretical findings promise great progress in light-pollution modeling as this is the first time an analytical solution to city emission function (CEF) has been developed that depends on statistical mean size and height of city buildings, inter-building separation, prevailing heights of light fixtures, lighting density, and other factors such as e.g. luminaire light output and light distribution, including the amount of uplight, and representative city size. The model is validated for sensitivity and specificity pertinent to combinations of input parameters in order to test its behavior under various conditions, including those that can occur in complex urban environments. It is demonstrated that the solution model succeeds in reproducing a light emission peak at some elevated zenith angles and is consistent with reduced rather than enhanced emission in directions nearly parallel to the ground.  
  Address  
  Corporate Author Thesis  
  Publisher (down) ScienceDirect Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number LoNNe @ kyba @ Serial 1757  
Permanent link to this record
 

 
Author Duriscoe, D.M.; Luginbuhl, C.B.; Elvidge, C.D. url  doi
openurl 
  Title The relation of outdoor lighting characteristics to sky glow from distant cities Type Journal Article
  Year 2014 Publication Lighting Research and Technology Abbreviated Journal Lighting Research and Technology  
  Volume 46 Issue 1 Pages 35-49  
  Keywords measurements; light pollution; light at night; Suomi NPP; satellite; remote sensing; VIIRS  
  Abstract Five cities in the southwest United States were selected for an analysis of the impact of outdoor lighting practices on nighttime sky glow as observed from distances of 8–67 km. Data from the Suomi National Polar-orbiting Partnership (NPP) satellite visible infrared imaging radiometer suite day/night band were used to identify light sources for input to an atmospheric sky glow model. Total lumens of outdoor lighting were estimated by matching modelled to observed anthropogenic sky luminance at ground locations. The results of two conservative treatments were then modelled for each city: all outdoor luminaires fully shielded with the current lumen amount, and fully shielded luminaires with a lumen amount scaled to 2075 lm/capita, matching Flagstaff, Arizona. The results indicate 42–88% reductions in average all-sky glow utilizing these ‘best practices’ for environmental conservation.  
  Address U.S. National Park Service Night Skies Program, Bishop, CA, USA  
  Corporate Author Thesis  
  Publisher (down) Sage Place of Publication Editor  
  Language Engligh 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 268  
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