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Author Aubé, M.; Fortin, N.; Turcotte, S.; García, B.; Mancilla, A.; Maya, J. url  doi
openurl 
  Title Evaluation of the Sky Brightness at Two Argentinian Astronomical Sites Type Journal Article
  Year 2014 Publication Publications of the Astronomical Society of the Pacific Abbreviated Journal Publications of the Astronomical Society of the Pacific  
  Volume (up) Issue Pages 000-000  
  Keywords Skyglow; light pollution; astronomical observatories; sky brightness; site selection; LEO ++; El Leoncito; Kitt Peak; Mont-Mégantic; Argentina  
  Abstract Light pollution is a growing concern at many levels, especially for the astronomical community. Indeed, not only does artificial lighting veil celestial objects, it disturbs the measurement of many atmospheric phenomena. The sky brightness is one of the most relevant parameters for astronomical site selection. Our goal is to evaluate the sky brightness of two Argentinian observation sites: LEO ++ and El Leoncito. Both sites were preselected to host the Cherenkov Telescope Array. This project consists of an arrangement of many telescopes that can measure high-energy gamma ray emissions via their Cherenkov radiation produced when entering the earth’s atmosphere. In this paper, we describe the measurement methods used to determine whether those sites are valuable or not. We compared our results with the sky radiance of different renowned astronomical sites (Kitt Peak, Arizona, and Mont-Mégantic, Québec, Canada). Among our results, we found that LEO ++ is a good site, however the presence of a low layer of local aerosol can introduce uncertainties in the measurements. Consequently, El Leoncito would be a better option for such an installation. This latter site shows very low sky brightness levels, which are optimal for low light detection.  
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  ISSN 0004-6280 ISBN Medium  
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  Call Number IDA @ john @ Serial 1071  
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Author Zielinska-Dabkowska, K.M. url  openurl
  Title Critical Perspectives On Media Architecture : Is It Still Possible To Design Projects Without Negatively Affecting Urban Nighttime Environments And Will The Future Remain Dynamic, Bright And Multi-Colored? Type Journal Article
  Year 2014 Publication World Cities Abbreviated Journal  
  Volume (up) Issue Pages 101-108  
  Keywords Planning, Design  
  Abstract Nowadays, due to advances in electrical devices, new digital media, lighting, in formation and communication technologies, cities are being used 24/7. The paper discusses critical aspects of Media Architecture in the context of public spaces as well as urban nighttime environments from the perspective of a practising lighting architect. The author examines recent issues of negative design approaches and presents proposals for improving future projects in the form of guiding principles. Additionally, to better illustrate the phenomenon, an attempt has been made to standardize terminology and to clarify the topic of Media Architecture in the context of artificial light used in the urban environment based on the author’s practical and theoretical research work in the field.  
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  Call Number LoNNe @ christopher.kyba @ Serial 1075  
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Author Yadav, G.; Malik, S.; Rani, S.; Kumar, V. url  doi
openurl 
  Title Role of light wavelengths in synchronization of circadian physiology in songbirds Type Journal Article
  Year 2014 Publication Physiology & Behavior Abbreviated Journal Physiol Behav  
  Volume (up) Issue Pages  
  Keywords Activity; Animals; Bunting; Cortisol; Light wavelength; Melatonin; Weaver bird  
  Abstract This study investigated whether at identical duration and equal energy level birds presented with short (450nm; blue, B) and long (640nm; red, R) light wavelengths would differentially interpret them and exhibit wavelength-dependent circadian behavioral and physiological responses, despite the difference in their breeding latitudes. Temperate migratory blackheaded buntings (Emberiza melanocephala) and subtropical non-migratory Indian weaverbirds (Ploceus philippinus) initially entrained to 12h light:12h darkness (12L:12D; L=0.33muM/m2/s, D=0muM/m2/s) in two groups of each, groups 1 and 2, were subjected to constant light (LL, 0.33muM/m2/s), which rendered them arrhythmic in the activity behavior. They were then exposed for about two weeks each to 12B:12R and 12R:12B (group 1) or 12R:12B and 12B:12R (group 2) at 0.33muM/m2/s light energy level. Blue and red light periods were interpreted as the day and night, respectively, with activity and no-activity in non-migratory weaverbirds or activity and intense activity (Zugunruhe, migratory night restlessness) in the migratory buntings. Consistent with this, plasma melatonin levels under B:R, not R:B, light cycle were low and high in blue and red light periods, respectively. A similar diurnal pattern was absent in the cortisol levels, however. These results show an important role of light wavelengths in synchronization of the circadian clock governed behavior and physiology to the photoperiodic environment, and suggest that photoperiodic timing might be a conserved physiological adaptation in many more birds, regardless of the difference in breeding latitudes, than has been generally envisaged.  
  Address DST-IRHPA Centre for Excellence in Biological Rhythms Research, Department of Zoology, University of Delhi, Delhi 110 007, India. Electronic address: drvkumar11@yahoo.com  
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  ISSN 0031-9384 ISBN Medium  
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  Notes PMID:25536387 Approved no  
  Call Number LoNNe @ christopher.kyba @ Serial 1080  
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Author Schroer, S.; Hölker, F. url  doi
openurl 
  Title Light Pollution Reduction Type Book Chapter
  Year 2014 Publication Handbook of Advanced Lighting Technology Abbreviated Journal  
  Volume (up) Issue Pages  
  Keywords ligting technology; awareness; skyglow, lighting design  
  Abstract Artificial light at night is an irreplaceable technology for our society and its activities at nighttime. But this indispensable tool has detrimental side effects, which have only come to light in the past 10–20 years. This chapter reviews ways to implement technology in order to lower the impact of artificial light at night on nature and humans. Further, it provides guidelines for environmental protection and scientific approaches to reduce the increase in light pollution and discusses the urgent need for further research. Measures to prevent obtrusive light and unintentional trespass into homes and natural habitats are

mostly simple solutions like shielding luminaires and predominantly require awareness. Shades are another effective tool to reduce trespass from interior lights. Especially in greenhouses, the use of shades significantly reduces the contribution to skyglow. Artificial light should be switched off whenever it is not needed. Smart, flexible lighting systems can help to use artificial light with precision. The choice of the appropriate illumination has to be balanced by the needs for optimal visibility, human well-being, environmental conservation and protection of the night sky. For visibility, conditions comparable to bright moonlit nights (0.3 lx) are sufficient. Low-level streetlights that produce only 1–3 lx at the surface meet the requirement of facial cognition. Although this light level might be too low for road safety, a consideration of maximum illumination levels in street lighting is recommended. The spectral power distribution of illuminants can impact several environmental parameters. For example, illuminants emitting short wavelengths can sup- press melatonin in higher vertebrates (including humans), are attracting many insect species, and contribute in skyglow above average. Recent findings in different measures for energy efficiency of illuminants at scotopic or mesopic vision conditions compared to photopic conditions indicate that the assessment of lighting products needs fundamental revision. Further research is crucially needed to create refuges for light-sensitive species at night, to measure the impact of artificial light on nature, and also to monitor the improvements of light pollution-reducing measures. Decrees in various regions have helped to lower the impact of artificial light at night significantly. Measures to reduce the impact of artificial light at night need to be carefully balanced with the surrounding environment. Thoughtful guidelines are crucial to reducing the rapid increase in sky brightness worldwide. These guidelines need to be made accessible for decision makers especially in areas which require new light installations.
 
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  Publisher Springer International Publishing Place of Publication Editor Karlicek, Robert Sun, Ching-Chern Zissis, Georgis Ma, Ruiqing  
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  Call Number LoNNe @ schroer @ Serial 1569  
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Author Clanton, N.; Gibbons, R.; Garcia, J.; Barber, M. url  doi
openurl 
  Title Seattle LED Adaptive Lighting Study Type Report
  Year 2014 Publication Northwest Energy Efficiency Alliance Abbreviated Journal NEEA  
  Volume (up) Issue E14-286 Pages  
  Keywords Public Safety; Lighting; Planning; Vision  
  Abstract The Northwest Energy Efficiency Alliance (NEEA) and the City of Seattle partnered to evaluate the future of solid state street lighting in the Pacific Northwest with a two-night demonstration in Seattle's Ballard neighborhood in March 2012. The study evaluates the effectiveness of LED streetlights on nighttime driver object detection visibility as function of light source spectral distribution (color temperature in degrees K) and light distribution. Clanton & Associates and VTTI also evaluated adaptive lighting (tuning of streetlights during periods of reduced vehicular and pedestrian activity) at three levels: one hundred percent of full light output, fifty percent of full light output, and twenty-five percent of full light output. The study, led by Clanton & Associates, Continuum Industries, and the VTTI, built upon previous visual performance studies conducted in Anchorage, Alaska; San Diego, California; and San Jose, California. The use of LED technology for city street lighting is becoming more widespread. While these lights are primarily touted for their energy efficiency, the combination of LEDs with advanced control technology, changes to lighting criteria, and a better understanding of human mesopic (low light level) visibility creates an enormous potential for energy savings and improved motorist and pedestrian visibility and safety. Data from these tests support the following statements: LED luminaires with a correlated color temperature of 4100K provide the highest detection distance, including statistically significantly better detection distance when compared to HPS luminaires of higher wattage. The non-uniformity of the lighting on the roadway surface provides a visibility enhancement and greater contrast for visibility. Contrast of objects, both positive and negative, is a better indicator of visibility than is average luminance level. Dimming the LED luminaires to fifty percent of IES RP-8 levels did not significantly reduce object detection distance in dry pavement conditions. Participants perceived dimming of sidewalks as less acceptable than dimming to the same level on the roadway. Asymmetric lighting did reduce glare and performed similarly to the symmetric lighting at the same color temperature (4100K).  
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  Notes Approved no  
  Call Number LoNNe @ kyba @ Serial 1763  
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