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Author den Outer, P.; Lolkema, D.; Haaima, M.; van der Hoff, R.; Spoelstra, H.; Schmidt, W.
Title Intercomparisons of nine sky brightness detectors Type Journal Article
Year 2011 Publication Sensors (Basel, Switzerland) Abbreviated Journal Sensors (Basel)
Volume 11 Issue 10 Pages 9603-9612
Keywords Calibration; Darkness; *Extraterrestrial Environment; Humans; Light; Luminescent Measurements; Netherlands; *Optical Phenomena; Optics and Photonics/*instrumentation/*methods; Sky Quality Meter; artificial lighting; intercalibration; intercomparison; light pollution; night sky brightness
Abstract Nine Sky Quality Meters (SQMs) have been intercompared during a night time measurement campaign held in the Netherlands in April 2011. Since then the nine SQMs have been distributed across The Netherlands and form the Dutch network for monitoring night sky brightness. The goal of the intercomparison was to infer mutual calibration factors and obtain insight into the variability of the SQMs under different meteorological situations. An ensemble average is built from the individual measurements and used as a reference to infer the mutual calibration factors. Data required additional synchronization prior to the calibration determination, because the effect of moving clouds combined with small misalignments emerges as time jitter in the measurements. Initial scatter of the individual instruments lies between +/-14%. Individual night time sums range from -16% to +20%. Intercalibration reduces this to 0.5%, and -7% to +9%, respectively. During the campaign the smallest luminance measured was 0.657 +/- 0.003 mcd/m(2) on 12 April, and the largest value was 5.94 +/- 0.03 mcd/m(2) on 2 April. During both occurrences interfering circumstances like snow cover or moonlight were absent.
Address (down) National Institute for Public Health and the Environment, A. van Leeuwenhoeklaan 9, 3720 BA Bilthoven, The Netherlands. peter.den.outer@rivm.nl
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 1424-8220 ISBN Medium
Area Expedition Conference
Notes PMID:22163715; PMCID:PMC3231263 Approved no
Call Number IDA @ john @ Serial 196
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Author Korompeli, A.; Kavrochorianou, N.; Molcan, L.; Muurlink, O.; Boutzouka, E.; Myrianthefs, P.; Fildissis, G.
Title Light affects heart rate's 24-h rhythmicity in intensive care unit patients: an observational study Type Journal Article
Year 2019 Publication Nursing in Critical Care Abbreviated Journal Nurs Crit Care
Volume 24 Issue 5 Pages 320-325
Keywords Lighting; Human Health; Heart Rate; ICU; Circadian Rhythm
Abstract BACKGROUND: Intensive care unit (ICU) patients experience two affronts to normal 24-h rhythms: largely internal events such as medication and external factors such as light, noise and nursing interventions. AIMS AND OBJECTIVES: We investigated the impact of light variance within an ICU on 24-h rhythmicity of three key physiological parameters: heart rate (HR), mean arterial blood pressure (MAP) and body temperature (BT) in this patient population. DESIGN: Patients were assigned to beds either in the 'light' or 'dark' side within a single ICU. An actigraph continuously recorded light intensity for a 24-72-h period. METHODS: Measurements of HR, MAP and BT were recorded every 30 min. RESULTS: HR, MAP and BT did not follow 24-h rhythmicity in all patients. Higher light exposure in the Light Side of the ICU (122.3 versus 50.6 lx) was related to higher HR (89.4 versus 79.8 bpm), which may translate to clinically relevant outcomes in a larger sample. Duration of stay, the one clinical outcome measured in this study, showed no significant variation between the groups (p = 0.147). CONCLUSIONS: ICU patients are exposed to varying light intensities depending on bed positioning relative to natural sunlight, affecting the 24-h rhythm of HR. Larger, well-controlled studies also investigating the effect of relevant light intensity are indicated. RELEVANCE TO CLINICAL PRACTICE: Light is a variable that can be manipulated in the constrained environment of an ICU, thus offering an avenue for relatively unobtrusive interventions.
Address (down) National and Kapodistrian University of Athens, University ICU, Ag. Anargyroi General Hospital, Athens, Greece
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 1362-1017 ISBN Medium
Area Expedition Conference
Notes PMID:31087602 Approved no
Call Number GFZ @ kyba @ Serial 2502
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Author Lewis, A.L.
Title Visual Performance as a Function of Spectral Power Distribution of Light Sources at Luminances Used for General Outdoor Lighting Type Journal Article
Year 1999 Publication Journal of the Illuminating Engineering Society Abbreviated Journal Journal of the Illuminating Engineering Society
Volume 28 Issue 1 Pages 37-42
Keywords Vision; spectral power distribution; SPD; lighting
Abstract (none)
Address (down) Michigan College of Optometry, Ferris State University, Big Rapids, Michigan
Corporate Author Thesis
Publisher Taylor & Francis Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0099-4480 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 2223
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Author Tähkämö, L.; Ylinen, A.; Puolakka, M.; Halonen, L.
Title Life cycle cost analysis of three renewed street lighting installations in Finland Type Journal Article
Year 2012 Publication The International Journal of Life Cycle Assessment Abbreviated Journal Int J Life Cycle Assess
Volume 17 Issue 2 Pages 154-164
Keywords LED; LED lighting; Life cycle costs; Light-emitting diode; Payback time; Road lighting; Street lighting
Abstract Purpose

Outdoor lighting is facing major changes due to the EU legislation on ecodesign of energy-related products, such as the ban of high-pressure mercury (HPM) lamps widely used in outdoor lighting. This article presents life cycle costs (LCC) of three examples of replacing HPM lamps in street lighting in Finland. The purpose of the article is to assess how the development of light-emitting diode (LED) technology affects LCCs and how the division of LCCs differentiates in the cases.

Methods

Two of the cases change from HPM lamps to high-pressure sodium (HPS) lamps. In the third one, HPM lamps are replaced by LED luminaires. LED technology predictions of price and luminous efficacy are included in different scenarios. The calculations consider investment and operating costs and residual value.

Results and discussion

Each replacement reduces the energy costs approximately by half compared to the original HPM lamp luminaires. Energy costs dominate the LCCs of the HPS lamp installations while investment cost is the dominating one in LED luminaire case. The changes from HPM to HPS technology have payback times lower than 9 years, while changing to LED luminaires is not economic. However, the electricity price is low in this case. The payback times of LED installations can be as low as 6 years if the luminaires are installed in 2015 and an average electricity price is used.

Conclusions

The LCCs of real-life case studies cannot be directly compared, since their luminous properties vary. There is a need for a method for including luminous properties in LCC calculations.
Address (down) Lighting Unit, School of Electrical Engineering, Aalto University, P.O. Box 13340, 00076, Aalto, Finland
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 0948-3349 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 332
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Author Sweater-Hickcox, K.; Narendran, N.; Bullough, J.; Freyssinier, J.
Title Effect of different coloured luminous surrounds on LED discomfort glare perception Type Journal Article
Year 2013 Publication Lighting Research and Technology Abbreviated Journal Lighting Research and Technology
Volume 45 Issue 4 Pages 464-475
Keywords perception; subjective; LED; LED lighting; spectral power distribution; SPD
Abstract Recently, there has been increased interest in energy-efficient lighting as energy resources become higher in demand. Anecdotal evidence suggests that certain populations believe light-emitting diodes (LED) produce more glare than traditional technologies. This may be due to a number of factors such as spectral power distribution (SPD), source luminance, or beam intensity distribution. A study was conducted to assess the effect of different SPDs on the perception of discomfort glare from an LED source. For the range of conditions evaluated, the presence of any luminous surround significantly reduced the perception of discomfort glare from the LED array. The blue luminous surround reduced discomfort glare perception significantly less than the white or the yellow luminous surrounds. The implications for solid-state lighting systems are discussed.
Address (down) Lighting Research Center, Rensselaer Polytechnic Institute, Troy, NY, USA
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 1477-1535 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 338
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