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Author Chen, S.; Li, W.; Yang, S.; Zhang, B.; Li, T.; Du, Y.; Yang, M.; Zhao, H.
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 (down) 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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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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 Barrette, T.P.; Pike, A.M.
Title Closed-Course Human Factors Evaluation of Marking and Marker Visibility Type Journal Article
Year 2019 Publication Transportation Research Record: Journal of the Transportation Research Board Abbreviated Journal (down) Transportation Research Record
Volume in press Issue Pages
Keywords Vision
Abstract Raised retroreflective pavement markers (RRPMs) are commonly used to provide nighttime delineation of roadways. Although RRPMs are visible during dry conditions, they provide their greatest benefit during wet-night conditions, when typical pavement markings become flooded and lose their retroreflectivite properties. Naturally, the retroreflectivity of RRPMs degrades over time as a result of traffic, ultraviolet light, precipitation, and roadway maintenance activities. Subsequently, it is necessary to examine the relationship between driver performance and the condition of the RRPMs. To assess visibility relative to RRPM condition, study participants rode in the passenger seat of a vehicle operated by a member of the research team, traveling at approximately 15 mph, for two laps around a closed course. Throughout each lap of the course, nine treatments consisting of RRPMs or preformed pavement marking tape of various retroreflectivity levels diverged from a center line to either the right or left. Participants indicated when they could tell which direction the treatment diverged, which was recorded using a GPS unit. A generalized linear model was estimated on a dataset constructed by pairing the observed distances from various treatments with demographic information about each participant. The analysis indicates the distance at which a particular treatment would be visible, which can then be converted to preview time to assess treatment adequacy for a variety of speeds. The RRPM treatments generally provided adequate preview time for older drivers based on the extant literature; however, the preformed pavement marking tape was less adequate at higher speeds and under overhead lighting.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0361-1981 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2499
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Author Flannagan, M.J.; Sivak, M.; Traube, E.C.; Kojima, S.
Title Effects of Overall Low-Beam Intensity on Seeing Distance in the Presence of Glare Type Journal Article
Year 2000 Publication Transportation Human Factors Abbreviated Journal (down) Transportation Human Factors
Volume 2 Issue 4 Pages 313-330
Keywords Public Safety; Vision
Abstract Previous studies have demonstrated that current low-beam headlamps do not provide adequate seeing distance for safety. Could this situation be improved by providing more total light from low-beam headlamps, leaving the relative distribution of light unchanged? Although such a proposal is probably not the best practical solution, it is important to consider some of the visual consequences of a general increase in light to analyze the overall problem of low-beam headlighting.

In a nighttime field study we measured seeing distance in the presence of glare as a function of headlamp intensity, always varying the intensity of the seeing light and glare light by the same proportion. Increasing intensity by a factor of about 3.8 increased seeing distance by about 17% for both young and old drivers. This result is consistent with predictions from quantitative vision modeling using veiling luminance to represent the disabling effects of glare. We also collected subjective estimates of discomfort glare and found, as expected, that the higher intensities produced substantially more discomfort.

Our findings suggest that, if objective visual performance is the only criterion, there is no clear upper limit to how intense low-beam headlamps should be. However, there may be a level at which people simply will not tolerate the subjectively discomforting effects of glare, or at which glare indirectly affects objective performance through its effects on subjective comfort. Because subjective discomfort, rather than objective visual performance, may be the limiting consideration for setting maximum glare levels, more research should be done to understand the nature and consequences of discomfort glare, including possible effects of subjective comfort on objective visual behavior.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1093-9741 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2127
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Author Bedrosian, T.A.; Nelson, R.J.
Title Timing of light exposure affects mood and brain circuits Type Journal Article
Year 2017 Publication Translational Psychiatry Abbreviated Journal (down) Transl Psychiatry
Volume 7 Issue 1 Pages e1017
Keywords Review; Human Health
Abstract Temporal organization of physiology is critical for human health. In the past, humans experienced predictable periods of daily light and dark driven by the solar day, which allowed for entrainment of intrinsic circadian rhythms to the environmental light-dark cycles. Since the adoption of electric light, however, pervasive exposure to nighttime lighting has blurred the boundaries of day and night, making it more difficult to synchronize biological processes. Many systems are under circadian control, including sleep-wake behavior, hormone secretion, cellular function and gene expression. Circadian disruption by nighttime light perturbs those processes and is associated with increasing incidence of certain cancers, metabolic dysfunction and mood disorders. This review focuses on the role of artificial light at night in mood regulation, including mechanisms through which aberrant light exposure affects the brain. Converging evidence suggests that circadian disruption alters the function of brain regions involved in emotion and mood regulation. This occurs through direct neural input from the clock or indirect effects, including altered neuroplasticity, neurotransmission and clock gene expression. Recently, the aberrant light exposure has been recognized for its health effects. This review summarizes the evidence linking aberrant light exposure to mood.
Address Department of Neuroscience, Behavioral Neuroendocrinology Group, The Ohio State University Wexner Medical Center, Columbus, OH, USA
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Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2158-3188 ISBN Medium
Area Expedition Conference
Notes PMID:28140399; PMCID:PMC5299389 Approved no
Call Number GFZ @ kyba @ Serial 2446
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Author Wickham, D.A.
Title Attracting and Controlling Coastal Pelagic Fish with Nightlights Type Journal Article
Year 1973 Publication Transactions of the American Fisheries Society Abbreviated Journal (down) Transactions of the American Fisheries Society
Volume 102 Issue 4 Pages 816-825
Keywords Animals
Abstract Field experiments were conducted in the northeastern Gulf of Mexico to evaluate techniques for using sequentially‐operated lamp strings and moving lamps to lead and concentrate light‐attracted coastal pelagic fishes. Fish were successfully led between sequentially‐operated under‐water lamps separated by distances up to 20 meters. Mobile lamps were used to lead fish distances up to approximately 1 kilometer. Fish aggregations which form daily around man‐made structures were held after dark and led clear with moving lamps for capture by purse seine. A combination of nightlighting and man‐made structure fish attraction techniques are proposed for harvesting coastal pelagic fish aggregations which occur around existing petroleton drilling platforms, well heads, and other areas presently inaccessible to conventional fishing gear.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-8487 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2452
Permanent link to this record