|   | 
Details
   web
Records
Author Kocifaj, M.; Solano Lamphar, H.A.
Title Skyglow: a retrieval of the approximate radiant intensity function of ground-based light sources Type Journal Article
Year 2014 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal Monthly Notices of the Royal Astronomical Society
Volume 439 Issue 4 Pages 3405-3413
Keywords radiative transfer; atmospheric effects; light pollution; methods: observational; site testing; skyglow; modeling
Abstract The angular distribution of the light emitted from a city is an important source of information about public lighting systems and it also plays a key role in modelling the skyglow. Usually, the upwardly directed radiation is characterized through a parametrized emission function – a semi-empirical approach as a reasonable approximation that allows for fast computations. However, theoretical or experimental retrievals of emission characteristics are extremely difficult to obtain because of both the complexity of radiative transfer methods and/or the lack of highly specialized measuring devices.

Our research has been conducted with the specific objective to identify an efficient theoretical technique for retrieval of the emission pattern of ground-based light sources in order to determine the optimum values of the scaling parameters of the Garstang function. In particular, the input data involve the zenith luminance or radiance with horizontal illuminance or irradiance. Theoretical ratios of zenith luminance LV(0) to horizontal illuminance DV are calculated for a set of distances d that separate a hypothetical observer from the light source (a city or town). This approach is advantageous because inexpensive traditional equipment can be used to obtain the mean values of the Garstang parameters. Furthermore, it can also be applied to other parametrizable emission functions and to any measuring site, even one with a masked horizon.
Address Department of Experimental Physics, Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynská dolina, 842 48 Bratislava, Slovak Republic
Corporate Author Thesis
Publisher Place of Publication Editor
Language (up) 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 Approved no
Call Number IDA @ john @ Serial 326
Permanent link to this record
 

 
Author Fuller, G. (ed)
Title The Night Shift: Lighting and Nocturnal Strepsirrhine Care in Zoos Type Book Whole
Year 2013 Publication Abbreviated Journal
Volume Issue Pages
Keywords zoos; light at night; circadian disruption; strepsirrhines; primates; lorises; pottos; lighting design
Abstract Over billions of years of evolution, light from the sun, moon, and stars has provided

organisms with reliable information about the passage of time. Photic cues entrain

the circadian system, allowing animals to perform behaviors critical for survival and

reproduction at optimal times. Modern artificial lighting has drastically altered

environmental light cues. Evidence is accumulating that exposure to light at night

(particularly blue wavelengths) from computer screens, urban light pollution, or as

an occupational hazard of night-shift work has major implications for human health.

Nocturnal animals are the shift workers of zoos; they are generally housed on

reversed light cycles so that daytime visitors can observe their active behaviors. As a

result, they are exposed to artificial light throughout their subjective night. The goal

of this investigation was to examine critically the care of nocturnal strepsirrhine

primates in North American zoos, focusing on lorises (Loris and Nycticebus spp.) and pottos (Perodicticus potto). The general hypothesis was that exhibit lighting design affects activity patterns and circadian physiology in nocturnal strepsirrhines. The

first specific aim was to assess the status of these populations. A multi-institutional husbandry survey revealed little consensus among zoos in lighting design, with both red and blue light commonly used for nocturnal illumination. A review of medical records also revealed high rates of neonate mortality. The second aim was to

develop methods for measuring the effects of exhibit lighting on behavior and

health. The use of actigraphy for automated activity monitoring was explored.

Methods were also developed for measuring salivary melatonin and cortisol as

indicators of circadian disruption. Finally, a multi-institutional study was conducted

comparing behavioral and endocrine responses to red and blue dark phase lighting.

These results showed greater activity levels in strepsirrhines housed under red light than blue. Salivary melatonin concentrations in pottos suggested that blue light

suppressed nocturnal melatonin production at higher intensities, but evidence for

circadian disruption was equivocal. These results add to the growing body of

evidence on the detrimental effects of blue light at night and are a step towards

empirical recommendations for nocturnal lighting design in zoos.
Address Department of Biology, Case Western Reserve University
Corporate Author Thesis Ph.D. thesis
Publisher Place of Publication Editor Fuller, G.
Language (up) Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 327
Permanent link to this record
 

 
Author Gil-de-Castro, A.; Moreno-Munoz, A.; Larsson, A.; de la Rosa, J.; Bollen, M.
Title LED street lighting: A power quality comparison among street light technologies Type Journal Article
Year 2013 Publication Lighting Research and Technology Abbreviated Journal Lighting Research and Technology
Volume 45 Issue 6 Pages 710-728
Keywords LED; LED lighting; high-pressure sodium; HPS; outdoor lighting; lighting technology
Abstract High-pressure sodium lamps are currently the main lamps used in public lighting. However, the possibility of using high-power light emitting diode (LEDs) for street lighting is growing continuously due to their greater energy efficiency, robustness, long life and light control. The aim of this paper is to study the power quality of high-power lighting networks based on LED and high-pressure sodium lamps. Both electromagnetic and dimmable electronic ballasts, which can dim the lamp output smoothly and uniformly, have been used connected to high-pressure sodium lamps. High-pressure sodium lamps connected to electronic equipment have been tested with different arc power levels using dimming on a 230 V power supply. The study presented in this paper is completely based on measurements, including harmonic currents in the frequency range up to 150 kHz for all the technologies. The main results show a broadband spectrum in LED lamps which confirms other research in fluorescent lamps powered by high-frequency ballasts. Results also indicate a decrease in the harmonic value with increasing harmonic order, and a decrease in the harmonic value at half load (60%) compared with full load (100%). Although total harmonic distortion of the current is lower with high-pressure sodium lamps connected to electronic rather than electromagnetic ballasts, LED lamps achieved the lowest total harmonic distortion of current.
Address Department of Computer Architecture, Electronics and Electronic Technology, University of Cordoba, Cordoba, Spain
Corporate Author Thesis
Publisher Place of Publication Editor
Language (up) Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1477-1535 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 333
Permanent link to this record
 

 
Author Johansson, M.; Rosen, M.; Kuller, R.
Title Individual factors influencing the assessment of the outdoor lighting of an urban footpath Type Journal Article
Year 2011 Publication Lighting Research and Technology Abbreviated Journal Lighting Research and Technology
Volume 43 Issue 1 Pages 31-43
Keywords footpath lighting; pathway lighting; outdoor lighting; lighting perception
Abstract During the hours of darkness, the mobility of young women, the elderly and the disabled is limited in urban areas. In a field study possible predictors of the perceived visual accessibility and the perceived danger of an urban footpath were investigated. Eighty-one people individually walked along the footpath after dark. They subjectively assessed the environment and answered a questionnaire about personality and socio-demographics. Visual accessibility was predicted by visual field, environmental trust and brightness. Danger was predicted by the pleasantness of the lighting, gender, brightness and environmental trust. Consequently, the influence of individual characteristics, including the subjective judgments of brightness and hedonic tone and the personality dimension of trust in the physical environment, should be considered in the design of exterior lighting for urban footpaths.
Address Environmental Psychology, Department of Architecture and Built Environment Lund University, Sweden
Corporate Author Thesis
Publisher Place of Publication Editor
Language (up) Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1477-1535 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 334
Permanent link to this record
 

 
Author Sperber, A.N.; Elmore, A.C.; Crow, M.L.; Cawlfield, J.D.
Title Performance evaluation of energy efficient lighting associated with renewable energy applications Type Journal Article
Year 2012 Publication Renewable Energy Abbreviated Journal Renewable Energy
Volume 44 Issue Pages 423-430
Keywords Renewable energy; Energy efficiency; Ultra capacitor; Light emitting diodes; Metal halide; LED; LED lighting
Abstract Energy efficiency is a primary consideration when designing off-grid renewable energy systems including portable micro-grids. This study focuses on characterizing the potential benefits associated with using energy efficient exterior area lighting commonly associated with remote installations. Light emitting diode (LED) luminaires are becoming more commercially available, and this study compares two LED products designed for exterior lighting to traditional metal halide lamps. The characterization focuses on the use of a diesel generator, battery bank, and a bank of ultra capacitors (UCAPs) to power the lights because these systems are also used to generate or store energy at renewable energy-powered micro-grids. This field-based study quantifies the illuminance provided by each lighting system, diesel consumption rates associated with powering the lights and/or charging the batteries and UCAPs, and the time of operation for each lighting system when powered by a single discharge cycle of the batteries and UCAPs. The energy efficiency benefit of the LED luminaires is offset by their lower illuminance. However, a comparison of lighting standards for specific purposes such as security lighting indicates that LEDs may be appropriate for applications where a metal halide system would provide significantly more illumination than required at a much higher energy cost. For those purposes where higher levels of illuminance are required, the data presented in the paper may be useful in designing a renewable energy-powered micro-grid that uses multiple LED fixtures to illuminate an exterior area that is currently illuminated by a single metal halide light stand.
Address Geological Engineering, Missouri University of Science and Technology, 129 McNutt Hall, 1400 N. Bishop Avenue Rolla, MO 65409, USA
Corporate Author Thesis
Publisher Place of Publication Editor
Language (up) Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0960-1481 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 335
Permanent link to this record