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Author Hyari, K.H.; Khelifi, A.; Katkhuda, H.
Title Multiobjective Optimization of Roadway Lighting Projects Type Journal Article
Year 2016 Publication Journal of Transportation Engineering Abbreviated Journal J. Transp. Eng.
Volume Issue Pages (down) 04016024
Keywords Lighting; multiobjective optimization; traffic safety; road safety; lighting design; uniformity; genetic algorithm
Abstract Roadway lighting systems play a major role in maintaining nighttime traffic safety as they reduce both the number and severity of nighttime traffic accidents. While the design of roadway lighting systems involves multiple objectives, past studies have focused on optimizing only one of the multiple objectives that should be considered. This paper presents a multiobjective optimization model for roadway lighting projects that simultaneously optimizes four design objectives. The incorporated objectives are (1) maximizing the average lighting level on the road surface; (2) maximizing the lighting uniformity along the roadway; (3) minimizing the glare to road users produced by the lighting system; and (4) minimizing the cost of operating the lighting system. The model is designed and developed as a multiobjective genetic algorithm to help decision-makers in their endeavor to provide efficient roadway lighting systems that strike a balance between the four conflicting objectives. The present model considers the following six design variables: type of lighting fixture, mounting height, spacing, fixture offset, fixture’s inclination, and fixture’s rotation angle. An application example is analyzed in this paper to clarify the use of the model and display its significant features in producing better lighting arrangements for roadways.
Address Dept. of Civil Engineering, Hashemite Univ., P.O. Box 150459, Zarqa 13115, Jordan; hyari(at)hu.edu.jo
Corporate Author Thesis
Publisher ASCE Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0733-947X ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1405
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Author Kaplan, K.A.; Mashash, M.; Williams, R.; Batchelder, H.; Starr-Glass, L.; Zeitzer, J.M.
Title Effect of Light Flashes vs Sham Therapy During Sleep With Adjunct Cognitive Behavioral Therapy on Sleep Quality Among Adolescents: A Randomized Clinical Trial Type Journal Article
Year 2019 Publication JAMA Network Open Abbreviated Journal JAMA Netw Open
Volume 2 Issue 9 Pages (down) e1911944
Keywords Human Health
Abstract Importance: Owing to biological, behavioral, and societal factors, sleep duration in teenagers is often severely truncated, leading to pervasive sleep deprivation. Objective: To determine whether a novel intervention, using both light exposure during sleep and cognitive behavioral therapy (CBT), would increase total sleep time in teenagers by enabling them to go to sleep earlier than usual. Design, Setting, and Participants: This double-blind, placebo-controlled, randomized clinical trial, conducted between November 1, 2013, and May 31, 2016, among 102 adolescents enrolled full-time in grades 9 to 12, who expressed difficulty going to bed earlier and waking up early enough, was composed of 2 phases. In phase 1, participants were assigned to receive either 3 weeks of light or sham therapy and were asked to try to go to sleep earlier. In phase 2, participants received 4 brief CBT sessions in addition to a modified light or sham therapy. All analyses were performed on an intent-to-treat basis. Interventions: Light therapy consisted of receiving a 3-millisecond light flash every 20 seconds during the final 3 hours of sleep (phase 1) or final 2 hours of sleep (phase 2). Sham therapy used an identical device, but delivered 1 minute of light pulses (appearing in 20-second intervals, for a total of 3 pulses) per hour during the final 3 hours of sleep (phase 1) or 2 hours of sleep (phase 2). Light therapy occurred every night during the 4-week intervention. Cognitive behavioral therapy consisted of four 50-minute in-person sessions once per week. Main Outcomes and Measures: Primary outcome measures included diary-based sleep times, momentary ratings of evening sleepiness, and subjective measures of sleepiness and sleep quality. Results: Among the 102 participants (54 female [52.9%]; mean [SD] age, 15.6 [1.1] years), 72 were enrolled in phase 1 and 30 were enrolled in phase 2. Mixed-effects models revealed that light therapy alone was inadequate in changing the timing of sleep. However, compared with sham therapy plus CBT alone, light therapy plus CBT significantly moved sleep onset a mean (SD) of 50.1 (27.5) minutes earlier and increased nightly total sleep time by a mean (SD) of 43.3 (35.0) minutes. Light therapy plus CBT also resulted in a 7-fold greater increase in bedtime compliance than that observed among participants receiving sham plus CBT (mean [SD], 2.21 [3.91] vs 0.29 [0.76]), as well as a mean 0.55-point increase in subjective evening sleepiness as compared with a mean 0.48-point decrease in participants receiving sham plus CBT as measured on a 7-point sleepiness scale. Conclusions and Relevance: This study found that light exposure during sleep, in combination with a brief, motivation-focused CBT intervention, was able to consistently move bedtimes earlier and increase total sleep time in teenagers. This type of passive light intervention in teenagers may lead to novel therapeutic applications. Trial Registration: ClinicalTrials.gov identifier: NCT01406691.
Address Stanford Center for Sleep Sciences and Medicine, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, California
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 2574-3805 ISBN Medium
Area Expedition Conference
Notes PMID:31553469 Approved no
Call Number GFZ @ kyba @ Serial 2683
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Author Figueiro, M.G.; Rea, M.S.
Title The effects of red and blue lights on circadian variations in cortisol, alpha amylase, and melatonin Type Journal Article
Year 2010 Publication International Journal of Endocrinology Abbreviated Journal Int J Endocrinol
Volume 2010 Issue Pages (down) 829351
Keywords blue light; red light; circadian rhythm; cortisol; alpha amylase; melatonin; photobiology; suprachiasmatic nuclei; endocrinology
Abstract The primary purpose of the present study was to expand our understanding of the impact of light exposures on the endocrine and autonomic systems as measured by acute cortisol, alpha amylase, and melatonin responses. We utilized exposures from narrowband long-wavelength (red) and from narrow-band short-wavelength (blue) lights to more precisely understand the role of the suprachiasmatic nuclei (SCN) in these responses. In a within-subjects experimental design, twelve subjects periodically received one-hour corneal exposures of 40 lux from the blue or from the red lights while continuously awake for 27 hours. Results showed-that, as expected, only the blue light reduced nocturnal melatonin. In contrast, both blue and red lights affected cortisol levels and, although less clear, alpha amylase levels as well. The present data bring into question whether the nonvisual pathway mediating nocturnal melatonin suppression is the same as that mediating other responses to light exhibited by the endocrine and the autonomic nervous systems.
Address Lighting Research Center, Rensselaer Polytechnic Institute, 21 Union Street, 3rd Floor, Troy, New York, NY 12180, 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 1687-8337 ISBN Medium
Area Expedition Conference
Notes PMID:20652045; PMCID:PMC2905913 Approved no
Call Number IDA @ john @ Serial 291
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Author Tsao, J.Y.; Saunders, H.D.; Creighton, J.R.; Coltrin, M.E.; Simmons, J.A.
Title Solid-state lighting: an energy-economics perspective Type Journal Article
Year 2010 Publication Journal of Physics D: Applied Physics Abbreviated Journal J. Phys. D: Appl. Phys.
Volume 43 Issue 35 Pages (down) 354001
Keywords artificial light; solid state; light emitting diode; LED; economics
Abstract Artificial light has long been a significant factor contributing to the quality and productivity of human life. As a consequence, we are willing to use huge amounts of energy to produce it. Solid-state lighting (SSL) is an emerging technology that promises performance features and efficiencies well beyond those of traditional artificial lighting, accompanied by potentially massive shifts in (a) the consumption of light, (b) the human productivity and energy use associated with that consumption and (c) the semiconductor chip area inventory and turnover required to support that consumption. In this paper, we provide estimates of the baseline magnitudes of these shifts using simple extrapolations of past behaviour into the future. For past behaviour, we use recent studies of historical and contemporary consumption patterns analysed within a simple energy-economics framework (a Cobb–Douglas production function and profit maximization). For extrapolations into the future, we use recent reviews of believed-achievable long-term performance targets for SSL. We also discuss ways in which the actual magnitudes could differ from the baseline magnitudes of these shifts. These include: changes in human societal demand for light; possible demand for features beyond lumens; and guidelines and regulations aimed at economizing on consumption of light and associated energy.
Address
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 0022-3727 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 127
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Author Foster, J.J.; Kirwan, J.D.; El Jundi, B.; Smolka, J.; Khaldy, L.; Baird, E.; Byrne, M.J.; Nilsson, D.-E.; Johnsen, S.; Dacke, M.
Title Orienting to polarized light at night – matching lunar skylight to performance in a nocturnal beetle Type Journal Article
Year 2019 Publication The Journal of Experimental Biology Abbreviated Journal J Exp Biol
Volume 222 Issue Pt 2 Pages (down) jeb188532
Keywords Animals; Natural skylight; insects; South African dung beetle; Escarabaeus satyrus; polarized light; Orientation
Abstract For polarized light to inform behaviour, the typical range of degrees of polarization observable in the animal's natural environment must be above the threshold for detection and interpretation. Here, we present the first investigation of the degree of linear polarization threshold for orientation behaviour in a nocturnal species, with specific reference to the range of degrees of polarization measured in the night sky. An effect of lunar phase on the degree of polarization of skylight was found, with smaller illuminated fractions of the moon's surface corresponding to lower degrees of polarization in the night sky. We found that the South African dung beetle Escarabaeus satyrus can orient to polarized light for a range of degrees of polarization similar to that observed in diurnal insects, reaching a lower threshold between 0.04 and 0.32, possibly as low as 0.11. For degrees of polarization lower than 0.23, as measured on a crescent moon night, orientation performance was considerably weaker than that observed for completely linearly polarized stimuli, but was nonetheless stronger than in the absence of polarized light.
Address Lund Vision Group, Department of Biology, Lund University, Solvegatan 35, 223 62 Lund, Sweden
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 0022-0949 ISBN Medium
Area Expedition Conference
Notes PMID:30530838 Approved no
Call Number GFZ @ kyba @ Serial 2599
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