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Author Kocifaj, M. url  doi
openurl 
  Title Modelling the spectral behaviour of night skylight close to artificial light sources Type Journal Article
  Year 2010 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal MNRAS  
  Volume 403 Issue 4 Pages 2105-2110  
  Keywords scattering; atmospheric effects; light pollution; methods: numerical; Modeling  
  Abstract Spectral features of the night sky are simulated under cloudless conditions. Numerical runs show that spectral composition of the diffuse light changes over the whole sky and sky radiances quickly respond to altering aerosol characteristics, such as the asymmetry parameter, single scattering albedo and total optical thickness. The general trend is a steep decrease of diffuse irradiance with a distance from the city centre. Powerstar HQI-NDL lamps produce more light at short wavelengths, thus implying the higher levels of light pollution. The red light may markedly contribute to the obtrusive light if Vialox NAV-4Y lamps are considered as a prevailing source of light in the model town. In a non-turbid atmosphere, the minimum radiance is notoriously observed close to the zenith. As aerosol loading increases, the minimum radiance is shifted to larger zenith angles at the opposite side of the light source. Obtained results may serve as corrections to spectrophotometry data, as the light pollution can be easily calculated for any sky element and for any spectral band.  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes (up) Approved no  
  Call Number IDA @ john @ Serial 276  
Permanent link to this record
 

 
Author Kocifaj, M. url  doi
openurl 
  Title Light-pollution model for cloudy and cloudless night skies with ground-based light sources Type Journal Article
  Year 2007 Publication Applied Optics Abbreviated Journal Appl. Opt.  
  Volume 46 Issue 15 Pages 3013  
  Keywords light pollution; modeling  
  Abstract The scalable theoretical model of light pollution for ground sources is presented. The model is successfully employed for simulation of angular behavior of the spectral and integral sky radiance and∕or luminance during nighttime. There is no restriction on the number of ground-based light sources or on the spatial distribution of these sources in the vicinity of the measuring point (i.e., both distances and azimuth angles of the light sources are configurable). The model is applicable for real finite-dimensional surface sources with defined spectral and angular radiating properties contrary to frequently used point-source approximations. The influence of the atmosphere on the transmitted radiation is formulated in terms of aerosol and molecular optical properties. Altitude and spectral reflectance of a cloud layer are the main factors introduced for simulation of cloudy and∕or overcast conditions. The derived equations are translated into numerically fast code, and it is possible to repeat the entire set of calculations in real time. The parametric character of the model enables its efficient usage by illuminating engineers and∕or astronomers in the study of various light-pollution situations. Some examples of numerical runs in the form of graphical results are presented.  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6935 ISBN Medium  
  Area Expedition Conference  
  Notes (up) Approved no  
  Call Number IDA @ john @ Serial 277  
Permanent link to this record
 

 
Author Xavier Kerola, D. url  doi
openurl 
  Title Modelling artificial night-sky brightness with a polarized multiple scattering radiative transfer computer code: Modelling artificial night-sky brightness Type Journal Article
  Year 2006 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal  
  Volume 365 Issue 4 Pages 1295-1299  
  Keywords Skyglow; modeling; radiative transfer; Gauss-Seidel; light pollution; Garstang model  
  Abstract As part of an ongoing investigation of radiative effects produced by hazy atmospheres, computational procedures have been developed for use in determining the brightening of the night sky as a result of urban illumination. The downwardly and upwardly directed radiances of multiply scattered light from an offending metropolitan source are computed by a straightforward Gauss-Seidel (G-S) iterative technique applied directly to the integrated form of Chandrasekhar's vectorized radiative transfer equation. Initial benchmark night-sky brightness tests of the present G-S model using fully consistent optical emission and extinction input parameters yield very encouraging results when compared with the double scattering treatment of Garstang, the only full-fledged previously available model.  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes (up) Approved no  
  Call Number IDA @ john @ Serial 278  
Permanent link to this record
 

 
Author Johansson, M.; Pedersen, E.; Maleetipwan-Mattsson, P.; Kuhn, L.; Laike, T. url  doi
openurl 
  Title Perceived outdoor lighting quality (POLQ): A lighting assessment tool Type Journal Article
  Year 2013 Publication Journal of Environmental Psychology Abbreviated Journal Journal of Environmental Psychology  
  Volume 39 Issue Pages 14-21  
  Keywords Perception; Street lighting; Observation-based environmental assessment; Urban space  
  Abstract A shift towards more energy-efficient light sources for outdoor lighting such as light-emitting diodes (LEDs) is underway. Photometric measures are not sufficient to capture how users experience the light, so complementary tools are required. This study aimed to develop an observer-based environmental assessment tool, based on bipolar semantic differentials, for outdoor lighting in urban spaces. Exploratory (N = 130) and confirmatory (N = 117) factor analyses of observations of lighting installations made by laypersons on-site along pedestrian paths, resulted in two dimensions of high reliability: the Perceived Strength Quality (PSQ, Cronbach's alpha = 0.82–0.85) and the Perceived Comfort Quality (PCQ, Cronbach's alpha = 0.77–0.81). PSQ and PCQ differentiated between light sources of different illuminance level, colour temperature and colour rendering. Regression analyses showed that the perceived lighting qualities helped to explain the variance in visual accessibility, whereas PCQ helped to explain perceived danger in the environment. The perceived lighting qualities can add to the understanding of pedestrians' perception of outdoor lighting, and is proposed as a complementary tool for development of sustainable light designs in the urban environment.  
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  Series Volume Series Issue Edition  
  ISSN 0272-4944 ISBN Medium  
  Area Expedition Conference  
  Notes (up) Approved no  
  Call Number IDA @ john @ Serial 279  
Permanent link to this record
 

 
Author Kuhn, L.; Johansson, M.; Laike, T.; Goven, T. url  doi
openurl 
  Title Residents' perceptions following retrofitting of residential area outdoor lighting with LEDs Type Journal Article
  Year 2013 Publication Lighting Research and Technology Abbreviated Journal Lighting Research and Technology  
  Volume 45 Issue 5 Pages 568-584  
  Keywords *Lighting; outdoor lighting; LED; light emitting diode; lighting levels; public opinion  
  Abstract The use of light emitting diodes (LEDs) in outdoor lighting has energy-saving potential, but users’ responses to this light source are largely unknown. An intervention study in two residential areas compared conventional lighting installations (high pressure sodium in Area 1 and high pressure mercury in Area 2) to a retrofitted LED-alternative regarding residents’ perceptions of quality of light, visual accessibility and danger. Moreover, energy use was calculated. Residents’ (N = 60) visual accessibility improved and perceived danger remained low in both areas after retrofitting. In Area 2 the perceived quality of light increased, whereas in Area 1 the results were mixed. The retrofitted application reduced energy use by 41–76% and might be a feasible alternative to conventional outdoor lighting in relatively safe areas.  
  Address Environmental Psychology, Department of Architecture and Built Environment, Lund University, Lund, Sweden  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1477-1535 ISBN Medium  
  Area Expedition Conference  
  Notes (up) Approved no  
  Call Number IDA @ john @ Serial 280  
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