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Author Luginbuhl, C.B.; Boley, P.A.; Davis, D.R. url  doi
openurl 
  Title The impact of light source spectral power distribution on sky glow Type Journal Article
  Year 2014 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer  
  Volume 139 Issue Pages 21-26  
  Keywords (up) Light pollution; Sky glow; Blue-rich light sources; LED; light emitting diode; lighting  
  Abstract The effect of light source spectral power distribution on the visual brightness of anthropogenic sky glow is described. Under visual adaptation levels relevant to observing the night sky, namely with dark-adapted (scotopic) vision, blue-rich (“white”) sources produce a dramatically greater sky brightness than yellow-rich sources. High correlated color temperature LEDs and metal halide sources produce a visual brightness up to 8× brighter than low-pressure sodium and 3× brighter than high-pressure sodium when matched lumen-for-lumen and observed nearby. Though the sky brightness arising from blue-rich sources decreases more strongly with distance, the visual sky glow resulting from such sources remains significantly brighter than from yellow sources out to the limits of this study at 300 km.  
  Address  
  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 0022-4073 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 178  
Permanent link to this record
 

 
Author Galadí-Enríquez, D. url  doi
openurl 
  Title Beyond CCT: The spectral index system as a tool for the objective, quantitative characterization of lamps Type Journal Article
  Year 2018 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal JQSRT  
  Volume 206 Issue Pages 399-408  
  Keywords (up) Lighting  
  Abstract Correlated color temperature (CCT) is a semi-quantitative system that roughly describes the spectra of lamps. This parameter gives the temperature (measured in kelvins) of the black body that would show the hue more similar to that of the light emitted by the lamp. Modern lamps for indoor and outdoor lighting display many spectral energy distributions, most of them extremely different to those of black bodies, what makes CCT to be far from a perfect descriptor from the physical point of view. The spectral index system presented in this work provides an accurate, objective, quantitative procedure to characterize the spectral properties of lamps, with just a few numbers. The system is an adaptation to lighting technology of the classical procedures of multi-band astronomical photometry with wide and intermediate-band filters. We describe the basic concepts and we apply the system to a representative set of lamps of many kinds. The results lead to interesting, sometimes surprising conclusions. The spectral index system is extremely easy to implement from the spectral data that are routinely measured at laboratories. Thus, including this kind of computations in the standard protocols for the certification of lamps will be really straightforward, and will enrich the technical description of lighting devices.  
  Address  
  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 GFZ @ kyba @ Serial 1835  
Permanent link to this record
 

 
Author Kocifaj, M. url  doi
openurl 
  Title Towards a Comprehensive City Emission Function (CCEF) Type Journal Article
  Year 2018 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal JQSRT  
  Volume 205 Issue Pages 253-266  
  Keywords (up) Lighting; Skyglow  
  Abstract The comprehensive city emission function (CCEF) is developed for a heterogeneous light-emitting or blocking urban environments, embracing any combination of input parameters that characterize linear dimensions in the system (size and distances between buildings or luminaires), properties of light-emitting elements (such as luminous building façades and street lighting), ground reflectance and total uplight-fraction, all of these defined for an arbitrarily sized 2D area. The analytical formula obtained is not restricted to a single model class as it can capture any specific light-emission feature for wide range of cities. The CCEF method is numerically fast in contrast to what can be expected of other probabilistic approaches that rely on repeated random sampling. Hence the present solution has great potential in light-pollution modeling and can be included in larger numerical models. Our theoretical findings promise great progress in light-pollution modeling as this is the first time an analytical solution to city emission function (CEF) has been developed that depends on statistical mean size and height of city buildings, inter-building separation, prevailing heights of light fixtures, lighting density, and other factors such as e.g. luminaire light output and light distribution, including the amount of uplight, and representative city size. The model is validated for sensitivity and specificity pertinent to combinations of input parameters in order to test its behavior under various conditions, including those that can occur in complex urban environments. It is demonstrated that the solution model succeeds in reproducing a light emission peak at some elevated zenith angles and is consistent with reduced rather than enhanced emission in directions nearly parallel to the ground.  
  Address  
  Corporate Author Thesis  
  Publisher ScienceDirect 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 Approved no  
  Call Number LoNNe @ kyba @ Serial 1757  
Permanent link to this record
 

 
Author Lamphar, H. url  doi
openurl 
  Title Spatio-temporal association of light pollution and urban sprawl using remote sensing imagery and GIS: A simple method based in Otsu's algorithm Type Journal Article
  Year 2020 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer  
  Volume 251 Issue Pages 107060  
  Keywords (up) Remote Sensing  
  Abstract Automatic thresholding methods are used to detect spatio-temporal changes in the land subject to different natural and anthropogenic processes. Image segmentation plays an important role in this analysis, where urban sprawl detection take place with daylight images. However, recently some investigators have used nocturnal images in remote sensing imagery research. Such georeferenced data represent a good tool for analysis of the light pollution and urban sprawl. There are various physical processes involved in the radiative transfer of the light projected from the cities. Though, with a correct method based on background subtraction, any satellite remotely sensed nocturnal image can be useful in detecting urban sprawl. We base this work on thresholding processes of georeferenced nocturnal satellite images. We used a method combining digital classification techniques, geographic information systems and statistical analyzes. The proposed method is helpful because of a simple implementation and time saving. The pixel intensity of nocturnal images can offer a tool to calculate aspects related to electricity consumption and the efficiency of public lighting. We hope the results motivates other authors to study relationships with other social, natural and economic issues.  
  Address  
  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 0022-4073 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2990  
Permanent link to this record
 

 
Author Min, M.; Zheng, J.; Zhang, P.; Hu, X.; Chen, L.; Li, X.; Huang, Y.; Zhu, L. url  doi
openurl 
  Title A low-light radiative transfer model for satellite observations of moonlight and earth surface light at night Type Journal Article
  Year 2020 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer  
  Volume in press Issue Pages 106954  
  Keywords (up) Remote Sensing; Instrumentation  
  Abstract Lunar sun-reflected light can be effectively measured through a low-light band or a day/night band (DNB) implemented on space-based optical sensors. Based on moonlight, nocturnal observations for artificial light sources at night can be achieved. However, to date, an open-sourced and mature Low-Light Radiative Transfer Model (LLRTM) for the further understanding of the radiative transfer problem at night is still unavailable. Therefore, this study develops a new LLRTM at night with the correction of the lunar and active surface light sources. First, the radiative transfer equations with an active surface light source are derived for the calculation based on the lunar spectral irradiance (LSI) model. The simulation from this new LLRTM shows a minimal bias when compared with the discrete ordinates radiative transfer (DISORT) model. The simulated results of radiance and reflectance at the top of the atmosphere (TOA) also show that the surface light source has a remarkable impact on the radiative transfer process. In contrast, the change in the lunar phase angle has minimal influence. Also, comparing with space-based DNB radiance observations, LLRTM shows the potential to simulate space-based low-light imager observations under an effective surface light source condition during the night.  
  Address  
  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 0022-4073 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2850  
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