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Author Bará, S.
Title Variations on a classical theme: On the formal relationship between magnitudes per square arcsecond and luminance Type Journal Article
Year 2017 Publication International Journal of Sustainable Lighting Abbreviated Journal Intl J of Sustainable Lighting
Volume 19 Issue 2 Pages 77
Keywords Instrumentation; skyglow; luminance; magnitude; sky brigthness; photometry
Abstract The formal link between magnitudes per square arcsecond and luminance is discussed in this paper. Directly related to the human visual system, luminance is defined in terms of the spectral radiance of the source, weighted by the CIE V(l) luminous efficiency function, and scaled by the 683 lm/W luminous efficacy constant. In consequence, any exact and spectrum-independent relationship between luminance and magnitudes per square arcsecond requires that the last ones be measured precisely in the CIE V(l) band. The luminance value corresponding to mVC=0 (zero-point of the CIE V(l) magnitude scale) depends on the reference source chosen for the definition of the magnitude system. Using absolute AB magnitudes, the zero point luminance of the CIE V(l) photometric band is 10.96 x 104 cd·m-2.
Address Departamento de Física Aplicada, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Galicia, Spain; salva.bara(at)usc.es
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2586-1247 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number (down) IDA @ john @ Serial 2162
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Author Bará, S.; Escofet, J.
Title On lamps, walls, and eyes: The spectral radiance field and the evaluation of light pollution indoors Type Journal Article
Year 2018 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal J of Quant Spect and Rad Trans
Volume 205 Issue Pages 267-277
Keywords Instrumentation; Light pollution; Artificial light at night; Light field; Radiance field; Radiometry; Photometry
Abstract Light plays a key role in the regulation of different physiological processes, through several visual and non-visual retinal phototransduction channels whose basic features are being unveiled by recent research. The growing body of evidence on the significance of these effects has sparked a renewed interest in the determination of the light field at the entrance pupil of the eye in indoor spaces. Since photic interactions are strongly wavelength-dependent, a significant effort is being devoted to assess the relative merits of the spectra of the different types of light sources available for use at home and in the workplace. The spectral content of the light reaching the observer eyes in indoor spaces, however, does not depend exclusively on the sources: it is partially modulated by the spectral reflectance of the walls and surrounding surfaces, through the multiple reflections of the light beams along all possible paths from the source to the observer. This modulation can modify significantly the non-visual photic inputs that would be produced by the lamps alone, and opens the way for controlling—to a certain extent—the subject's exposure to different regions of the optical spectrum. In this work we evaluate the expected magnitude of this effect and we show that, for factorizable sources, the spectral modulation can be conveniently described in terms of a set of effective filter-like functions that provide useful insights for lighting design and light pollution assessment. The radiance field also provides a suitable bridge between indoor and outdoor light pollution studies.
Address Área de Óptica, Departamento de Física Aplicada, Universidade de Santiago de Compostela, Santiago de Compostela, Galicia, Spain; salva.bara(at)usc.es
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4073 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number (down) IDA @ john @ Serial 2163
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Author Jones, B.A.
Title Spillover health effects of energy efficiency investments: Quasi-experimental evidence from the Los Angeles LED streetlight program Type Journal Article
Year 2018 Publication Journal of Environmental Economics and Management Abbreviated Journal Journal of Environmental Economics and Management
Volume 88 Issue Pages 283-299
Keywords Human Health; LED; public health; outdoor lighting; Los Angeles; economics; energy efficiency; breast cancer; fossil fuel carbon emissions
Abstract Payback estimates of energy efficiency investments often ignore public health externalities. This is problematic in cases where spillover health effects are substantial, such as when the application of new technology alters environmental exposures. When health externalities are included in return on investment calculations, energy efficiency programs may look more or less attractive than suggested by conventional “energy savings only” estimates. This analysis exploits the quasi-experiment provided by the 2009 Los Angeles (LA) LED streetlight efficiency program to investigate the returns on investments inclusive of an originally estimated health externality. Using the synthetic control method, we find that the LED streetlight program is associated with a lagged increase in breast cancer mortality of 0.479 per 100,000. Inclusive of the effects of LEDs on breast cancer and avoided carbon emissions, the LA LED program provides a −146.2% 10-year return compared to +118.2% when health outcomes and carbon emissions are ignored.
Address Department of Economics, University of New Mexico, 1 UNM Drive, MSC 05 3060, Albuquerque, NM, 87131, USA; bajones(at)unm.edu
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0095-0696 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number (down) IDA @ john @ Serial 1976
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Author Gaynor, K.M.; Hojnowski, C.E.; Carter, N.H.; Brashares, J.S.
Title The influence of human disturbance on wildlife nocturnality Type Journal Article
Year 2018 Publication Science (New York, N.Y.) Abbreviated Journal Science
Volume 360 Issue 6394 Pages 1232-1235
Keywords
Abstract Rapid expansion of human activity has driven well-documented shifts in the spatial distribution of wildlife, but the cumulative effect of human disturbance on the temporal dynamics of animals has not been quantified. We examined anthropogenic effects on mammal diel activity patterns, conducting a meta-analysis of 76 studies of 62 species from six continents. Our global study revealed a strong effect of humans on daily patterns of wildlife activity. Animals increased their nocturnality by an average factor of 1.36 in response to human disturbance. This finding was consistent across continents, habitats, taxa, and human activities. As the global human footprint expands, temporal avoidance of humans may facilitate human-wildlife coexistence. However, such responses can result in marked shifts away from natural patterns of activity, with consequences for fitness, population persistence, community interactions, and evolution.
Address Department of Environmental Science, Policy, and Management, University of California-Berkeley, Berkeley, CA 94720, USA
Corporate Author Thesis
Publisher AAAS Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0036-8075 ISBN Medium
Area Expedition Conference
Notes PMID:29903973 Approved no
Call Number (down) IDA @ john @ Serial 1988
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Author Wren, W.; Locke, S.
Title Upgraded Rig Lighting Improves Night Time Visibility While Reducing Stray Light and the Threat to Dark Skies in West Texas Type Conference Article
Year 2015 Publication Society of Petroleum Engineers Abbreviated Journal Soc. Petrol. Engr.
Volume Issue Pages
Keywords Lighting; outdoor lighting; petroleum; oil and gas; lighting engineering
Abstract McDonald Observatory, part of the University of Texas at Austin, is a world-class astronomical-research facility representing hundreds of millions of dollars of public and private investment that is increasingly threatened by nighttime lighting from oil-and-gas-related activities in and around the Permian Basin. Established in the remote Davis Mountains of West Texas in 1932, the observatory is home to some of the world's largest telescopes and it has continued as a world-renowned research center. Dark night skies are crucial to its mission. Since 2010, however, the sky along the observatory's northern horizon, in the direction of the Permian Basin, has been steadily and rapidly brightening, due to new exploration for oil and gas. The pace has been accelerating: More than 2,000 applications were filed over the past year to drill in the region. In 2011, the State of Texas enacted a law that instructs the seven counties surrounding McDonald Observatory, an area covering some 28,000 square miles, to adopt outdoor lighting ordinances designed to preserve the dark night skies for ongoing astronomical research at the observatory. Most had already done so voluntarily, but additional effort is needed throughout the area to address fast-moving energy-exploration activities.

A joint project between McDonald Observatory and Pioneer Energy Services (PES) has demonstrated that many of the adverse effects of oilfield lighting can be mitigated, without jeopardizing safety, through proper shielding and aiming of light fixtures. Beginning July, 2013, PES granted the observatory access to a working rig, Pioneer Rig #29. Every time the rig moved to a new location, there was an opportunity to install shields, re-aim floodlights, and evaluate effectiveness.

This joint project demonstrated that, in many cases, nighttime visibility on the rig can be significantly improved. Many light fixtures, which had been sources of blinding glare due to of lack of shielding, poor placement, or poor aiming, were made better and safer, using optional glare shields that are offered by manufacturers for a variety of fixture models. Proper shielding and aiming of existing fixtures improves visibility and reduces wasted uplight. New lighting systems that take advantage of light-emitting-diode technology also promise better directionality, reduced fuel consumption, and darker skies overhead.

The oil-and-gas industry has been lighting its exploration and production activities in much same way for more than 100 years, with little to no consideration of environmental impacts. The opportunity exists to adopt new lighting practices and technologies that improve safety, reduce costs, and help preserve our vanishing night skies so that important ongoing scientific exploration can continue.
Address
Corporate Author Thesis
Publisher Society of Petroleum Engineers Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes SPE E&P Health, Safety, Security and Environmental Conference-Americas held in Denver, Colorado, USA, 16–18 March 2015 Approved no
Call Number (down) IDA @ john @ Serial 1993
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