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Fuller, G. (Ed.). (2013). The Night Shift: Lighting and Nocturnal Strepsirrhine Care in Zoos. Ph.D. thesis, , .
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.
Gil-de-Castro, A., Moreno-Munoz, A., Larsson, A., de la Rosa, J., & Bollen, M. (2013). LED street lighting: A power quality comparison among street light technologies. Lighting Research and Technology, 45(6), 710–728.
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.
Johansson, M., Rosen, M., & Kuller, R. (2011). Individual factors influencing the assessment of the outdoor lighting of an urban footpath. Lighting Research and Technology, 43(1), 31–43.
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.
Sperber, A. N., Elmore, A. C., Crow, M. L., & Cawlfield, J. D. (2012). Performance evaluation of energy efficient lighting associated with renewable energy applications. Renewable Energy, 44, 423–430.
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.
Kostic, A., & Djokic, L. (2014). Subjective impressions under LED and metal halide lighting. Lighting Research and Technology, 46(3), 293–307.
Abstract: In order to compare subjective impressions created by LED and metal halide ambient lighting, a pilot project was conducted in a Belgrade park. All general requirements for an adequate comparison of subjective impressions were fulfilled. The survey was conducted using a questionnaire related to all aspects the researchers considered relevant for subjective evaluation of illuminated pedestrian paths in parks. It was concluded that the respondents, both those who had and those who did not have previous knowledge in the field of lighting, strongly preferred the use of metal halide lamps for the illumination of parks, which is in opposition to the statements of some LED manufacturers. It was also shown that light level and feelings of safety and comfort are evaluated as most important.