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Author Cai, W.; Yue, J.; Dai, Q.; Hao, L.; Lin, Y.; Shi, W.; Huang, Y.; Wei, M. url  doi
openurl 
  Title (down) The impact of room surface reflectance on corneal illuminance and rule-of-thumb equations for circadian lighting design Type Journal Article
  Year 2018 Publication Building and Environment Abbreviated Journal Building and Environment  
  Volume 141 Issue Pages 288-297  
  Keywords Lighting  
  Abstract Recently, corneal illuminance attracts much attention because it is closely related to important functions of indoor lighting. Especially, applying circadian light in the built environment places a challenging requirement on indirect corneal illuminance. In this work, rule-of-thumb equations are proposed to guide circadian lighting design: (i) for artificial lighting, Ecor,avg (i) = (Φ/C1) · ρ/(1−ρ′), where Ecor,avg (i) is the average indirect corneal illuminance at standing or sitting positions, Φ is the initial flux from luminaires, C1 is a constant comparable to the total room surface area, ρ is the reflectance of the surface where the first reflection occurs, and ρ′ is the area-weighted average of surface reflectance; and (ii) for daylighting, Ecor,avg (i) = C2 · WWR · ρ/(1−ρ′), where C2 is a constant, and WWR represents the window-to-wall ratio.

The equations above are validated by comparing against numerical simulation data obtained with the Radiance software. For artificial lighting simulation, various combinations of room surface reflectance, initial light distribution, and WWR are investigated; and for daylighting simulation, different combinations of surface reflectance, WWR, and geographic location are analyzed. The good fits to simulation data indicate that the proposed simple equations can provide reasonably accurate results for quick feedback at the field. It is also demonstrated that room surface reflectance has a dominant impact on indirect corneal illuminance. The approach of improving surface reflectance is more favorable than increasing luminaire flux or expanding window area, and therefore should be the recommended approach to achieve quality and efficient circadian lighting.
 
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  ISSN 0360-1323 ISBN Medium  
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  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1929  
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Author Luginbuhl, C.B.; Boley, P.A.; Davis, D.R. url  doi
openurl 
  Title (down) The impact of light source spectral power distribution on sky glow Type Journal Article
  Year 2014 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer  
  Volume 139 Issue Pages 21-26  
  Keywords Light pollution; Sky glow; Blue-rich light sources; LED; light emitting diode; lighting  
  Abstract The effect of light source spectral power distribution on the visual brightness of anthropogenic sky glow is described. Under visual adaptation levels relevant to observing the night sky, namely with dark-adapted (scotopic) vision, blue-rich (“white”) sources produce a dramatically greater sky brightness than yellow-rich sources. High correlated color temperature LEDs and metal halide sources produce a visual brightness up to 8× brighter than low-pressure sodium and 3× brighter than high-pressure sodium when matched lumen-for-lumen and observed nearby. Though the sky brightness arising from blue-rich sources decreases more strongly with distance, the visual sky glow resulting from such sources remains significantly brighter than from yellow sources out to the limits of this study at 300 km.  
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  Series Volume Series Issue Edition  
  ISSN 0022-4073 ISBN Medium  
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  Notes Approved no  
  Call Number IDA @ john @ Serial 178  
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Author Fressoz, J.-B. url  doi
openurl 
  Title (down) The Gas Lighting Controversy: Technological Risk, Expertise, and Regulation in Nineteenth-Century Paris and London Type Journal Article
  Year 2007 Publication Journal of Urban History Abbreviated Journal Journal of Urban History  
  Volume 33 Issue 5 Pages 729-755  
  Keywords Lighting; Regulations  
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  Series Volume Series Issue Edition  
  ISSN 0096-1442 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number LoNNe @ kagoburian @ Serial 1037  
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Author Tyndall, J. url  openurl
  Title (down) The Electric Light Type Journal Article
  Year 1879 Publication Fortnightly review Abbreviated Journal  
  Volume 25 Issue 146 Pages 197-216  
  Keywords History; Lighting; Review  
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  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2378  
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Author Skeldon, A.C.; Phillips, A.J.K.; Dijk, D.-J. url  doi
openurl 
  Title (down) The effects of self-selected light-dark cycles and social constraints on human sleep and circadian timing: a modeling approach Type Journal Article
  Year 2017 Publication Scientific Reports Abbreviated Journal Sci Rep  
  Volume 7 Issue Pages 45158  
  Keywords human health, lighting  
  Abstract Why do we go to sleep late and struggle to wake up on time? Historically, light-dark cycles were dictated by the solar day, but now humans can extend light exposure by switching on artificial lights. We use a mathematical model incorporating effects of light, circadian rhythmicity and sleep homeostasis to provide a quantitative theoretical framework to understand effects of modern patterns of light consumption on the human circadian system. The model shows that without artificial light humans wakeup at dawn. Artificial light delays circadian rhythmicity and preferred sleep timing and compromises synchronisation to the solar day when wake-times are not enforced. When wake-times are enforced by social constraints, such as work or school, artificial light induces a mismatch between sleep timing and circadian rhythmicity ('social jet-lag'). The model implies that developmental changes in sleep homeostasis and circadian amplitude make adolescents particularly sensitive to effects of light consumption. The model predicts that ameliorating social jet-lag is more effectively achieved by reducing evening light consumption than by delaying social constraints, particularly in individuals with slow circadian clocks or when imposed wake-times occur after sunrise. These theory-informed predictions may aid design of interventions to prevent and treat circadian rhythm-sleep disorders and social jet-lag.  
  Address University of Surrey, Surrey Sleep Research Centre, Guildford, GU2 7XP, UK  
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  Language English Summary Language Original Title  
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  ISSN 2045-2322 ISBN Medium  
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  Notes PMID:28345624 Approved no  
  Call Number SU @ spitschan @ Serial 1638  
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