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Author (up) Chen, S.; Li, W.; Yang, S.; Zhang, B.; Li, T.; Du, Y.; Yang, M.; Zhao, H. url  doi
openurl 
  Title Evaluation method and reduction measures for the flicker effect in road lighting using fixed Low Mounting Height Luminaires Type Journal Article
  Year 2019 Publication Tunnelling and Underground Space Technology Abbreviated Journal Tunnelling and Underground Space Technology  
  Volume 93 Issue Pages 103101  
  Keywords Lighting; Vision  
  Abstract Low Mounting Height Luminaires (LMHL) are used in many cities on viaducts, cross-sea and cross-river bridges due to their unique advantages. However, the flicker effect is an important factor that needs to be considered in road lighting using fixed LMHL. At present, there are not many researchers in the field of international lighting. Previous types of road lighting design were based on the method of the tunnel lighting flicker effect. At the same time, the flicker effect is mainly based on the subjective feelings of people but is not quantified. In this paper, the Flicker Index (FI) is calculated by measuring the parameters of streetlamps to evaluation flicker effect. Secondly, the suggestion to offset the flicker effect in CIE 88-2004 “Guide for the Lighting of Road Tunnels and Underpasses” is to limit the speed of the vehicle and adjust the road light spacing to avoid the flicker sensitive area on human eyes, while ignoring the essential problem of how the flicker effect is generated through the energy level of the stimulating optical signal. Two factors affecting the strength of the flicker effect are proposed: energy ratio and duty cycle. The duty cycle, in time, refers to the proportion of the strong and weak flashing signals during the period; in space, it refers to the proportional relationship between the length of the luminaire and the distance between the lamps, which is related to the running speed of the vehicle. It is consistent with the CIE recommendations for flicker. Thirdly, the essence of the flicker effect is the problem of the energy level of the stimulus signal. This study investigated the reduction in the brightness of the light source, hence reducing the energy of the visual stimulation signal to the human eye in order to judge the degree of fatigue in human vision. The experimental results show that the degree of fatigue in human vision decreases when the brightness of the experimental light source decreases. Therefore, the key to changing the flicker effect of LMHL is to reduce the contrast between the surface brightness of the luminaire and the brightness of the spatial background.  
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  Corporate Author Thesis  
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  Series Volume Series Issue Edition  
  ISSN 0886-7798 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2663  
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Author (up) LeGates, T.A.; Altimus, C.M.; Wang, H.; Lee, H.-K.; Yang, S.; Zhao, H.; Kirkwood, A.; Weber, E.T.; Hattar, S. url  doi
openurl 
  Title Aberrant light directly impairs mood and learning through melanopsin-expressing neurons Type Journal Article
  Year 2012 Publication Nature Abbreviated Journal Nature  
  Volume 491 Issue 7425 Pages 594-598  
  Keywords Affect/drug effects/physiology/*radiation effects; Animals; Antidepressive Agents/pharmacology; Body Temperature Regulation/physiology/radiation effects; Circadian Rhythm/physiology; Cognition/drug effects/physiology/radiation effects; Corticosterone/metabolism; Depression/etiology/physiopathology; Desipramine/pharmacology; Fluoxetine/pharmacology; Learning/drug effects/physiology/*radiation effects; *Light; Long-Term Potentiation/drug effects; Male; Memory/physiology/radiation effects; Mice; Photoperiod; Retinal Ganglion Cells/drug effects/*metabolism/*radiation effects; *Rod Opsins/analysis; Sleep/physiology; Wakefulness/physiology  
  Abstract The daily solar cycle allows organisms to synchronize their circadian rhythms and sleep-wake cycles to the correct temporal niche. Changes in day-length, shift-work, and transmeridian travel lead to mood alterations and cognitive function deficits. Sleep deprivation and circadian disruption underlie mood and cognitive disorders associated with irregular light schedules. Whether irregular light schedules directly affect mood and cognitive functions in the context of normal sleep and circadian rhythms remains unclear. Here we show, using an aberrant light cycle that neither changes the amount and architecture of sleep nor causes changes in the circadian timing system, that light directly regulates mood-related behaviours and cognitive functions in mice. Animals exposed to the aberrant light cycle maintain daily corticosterone rhythms, but the overall levels of corticosterone are increased. Despite normal circadian and sleep structures, these animals show increased depression-like behaviours and impaired hippocampal long-term potentiation and learning. Administration of the antidepressant drugs fluoxetine or desipramine restores learning in mice exposed to the aberrant light cycle, suggesting that the mood deficit precedes the learning impairments. To determine the retinal circuits underlying this impairment of mood and learning, we examined the behavioural consequences of this light cycle in animals that lack intrinsically photosensitive retinal ganglion cells. In these animals, the aberrant light cycle does not impair mood and learning, despite the presence of the conventional retinal ganglion cells and the ability of these animals to detect light for image formation. These findings demonstrate the ability of light to influence cognitive and mood functions directly through intrinsically photosensitive retinal ganglion cells.  
  Address Department of Biology, Johns Hopkins University, Baltimore, Maryland 21218, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-0836 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23151476; PMCID:PMC3549331 Approved no  
  Call Number IDA @ john @ Serial 238  
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