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Author Kyba, C.C.M.; Giuliani, G.; Franziskakis, F.; Tockner, K.; Lacroix, P. url  doi
openurl 
  Title Artisanal and Small-Scale Mining Sites in the Democratic Republic of the Congo Are Not Associated with Nighttime Light Emissions Type Journal Article
  Year 2019 Publication J Abbreviated Journal J  
  Volume 2 Issue 2 Pages 152-161  
  Keywords Remote Sensing  
  Abstract Maintaining records of artisanal and small-scale mining sites in developing countries requires considerable effort, so it would be beneficial if Earth observation data from space could assist in the identifying and monitoring of such sites. Artificial light emissions are common at industrial-scale mining sites and have been associated with small-scale illegal mining in some contexts. Here, we examine whether known artisanal and small-scale mining sites in the Democratic Republic of the Congo (DRC) are associated with observations of night light emissions by the Visible Infrared Imaging Radiometer Suite Day/Night Band (DNB). Light emissions from the mining sites were not observed: the radiance observed from the sites was near zero and nearly identical to that observed for a set of randomly-chosen locations in the same region. While it is the case that DNB night lights’ products provide useful data in other resource extraction contexts, they do not appear to be useful for identifying artisanal mining sites in the DRC.  
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  Series Volume Series Issue Edition  
  ISSN 2571-8800 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2295  
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Author Ogando-Martínez, A.; Troncoso-Pastoriza, F.; Eguía-Oller, P.; Granada-Álvarez, E.; Erkoreka, A. url  doi
openurl 
  Title Model Calibration Methodology to Assess the Actual Lighting Conditions of a Road Infrastructure Type Journal Article
  Year 2020 Publication Infrastructures Abbreviated Journal Infrastructures  
  Volume 5 Issue 1 Pages 2  
  Keywords Lighting  
  Abstract Street lighting plays an important role in the comfort and safety of drivers and pedestrians, so the control and management of the lighting systems operation and consumption is an essential service for a city. In this document, a methodology is presented to calibrate lighting models in order to assess the lighting performance through simulation techniques. The objective of this calibration is to identify the maintenance factor of the street lamps, determine the real average luminance coefficient of the road pavement and adapt the reflection properties of the road material. The method is applied in three stages and is based on the use of Radiance and GenOpt software suits for the modeling, simulation, and calibration of lighting scenes. The proposed methodology achieves errors as low as 13% for the calculation of illuminance and luminance, evincing its potential to assess the actual lighting conditions of a road.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2412-3811 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2802  
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Author Kolláth, Z.; Száz, D.; Tong, K.P.; Kolláth, K. url  doi
openurl 
  Title The Colour of the Night Sky Type Journal Article
  Year 2020 Publication Journal of Imaging Abbreviated Journal J. Imaging  
  Volume 6 Issue 9 Pages 90  
  Keywords Skyglow; Natural light; Instrumentation  
  Abstract The measurement of night sky quality has become an important task in night sky conservation. Modern measurement techniques involve mainly a calibrated digital camera or a spectroradiometer. However, panchromatic devices are still prevalent to this day, even in the absence of determining the spectral information of the night sky. In the case of multispectral measurements, colour information is currently presented in multiple ways. One of the most frequently used metrics is correlated colour temperature (CCT), which is not without its limitation for the purpose of describing especially the colour of natural night sky. Moreover, visually displaying the colour of the night sky in a quantitatively meaningful way has not attracted sufficient attention in the community of astronomy and light pollution research—most photographs of the night sky are post-processed in a way for aesthetic attractiveness rather than accurate representation of the night sky. The spectrum of the natural night sky varies in a wide range depending on solar activity and atmospheric properties. The most noticeable variation in the visible range is the variation of the atomic emission lines, primarily the green oxygen and orange sodium emission. Based on the accepted models of night sky emission, we created a random spectral database which represents the possible range of night sky radiance distribution. We used this spectral database as a learning set, to create a colour transformation between different colour spaces. The spectral sensitivity of some digital cameras is also used to determine an optimal transformation matrix from camera defined coordinates to real colours. The theoretical predictions were extended with actual spectral measurements in order to test the models and check the local constituents of night sky radiance. Here, we present an extended modelling of night sky colour and recommendations of its consistent measurement, as well as methods of visualising the colour of night sky in a consistent way, namely using the false colour enhancement.  
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  Series Volume Series Issue Edition  
  ISSN 2313-433X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 3120  
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Author Kolláth, Z.; Száz, D.; Kolláth, K.; Tong, K.P. url  doi
openurl 
  Title Light Pollution Monitoring and Sky Colours Type Journal Article
  Year 2020 Publication Journal of Imaging Abbreviated Journal J. Imaging  
  Volume 6 Issue 10 Pages 104  
  Keywords Skyglow; Instrumentation; light pollution; imaging radiometry; colorimetry  
  Abstract The measurement of night sky quality has become an important task in nature conservation. The primary device used for this task can be a calibrated digital camera. In addition, colour information can be derived from sky photography. In this paper, we provide a test on a concept to gather information about the possible sources of night sky brightness based on digital camera images. This method helps to understand changes in night sky quality due to natural and artificial changes in the environment. We demonstrate that a well-defined colour–colour diagram can differentiate between the different natural and artificial sources of night sky radiance. The colour information can be essential when interpreting long-term evolution of light pollution measurements.  
  Address Department of Physics, Eötvös Loránd University (ELTE) BDPK, 9700 Szombathely, Hungary; zkollath( at ) gmail.com  
  Corporate Author Thesis  
  Publisher MDPI Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2313-433X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 3170  
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Author Jechow, A.; Hölker, F. url  doi
openurl 
  Title Snowglow—The Amplification of Skyglow by Snow and Clouds can Exceed Full Moon Illuminance in Suburban Areas Type Journal Article
  Year 2019 Publication Journal of Imaging Abbreviated Journal J. Imaging  
  Volume 5 Issue 8 Pages 69  
  Keywords Skyglow  
  Abstract Artificial skyglow, the fraction of artificial light at night that is emitted upwards from Earth and subsequently scattered back within the atmosphere, depends on atmospheric conditions but also on the ground albedo. One effect that has not gained much attention so far is the amplification of skyglow by snow, particularly in combination with clouds. Snow, however, has a very high albedo and can become important when the direct upward emission is reduced when using shielded luminaires. In this work, first results of skyglow amplification by fresh snow and clouds measured with all-sky photometry in a suburban area are presented. Amplification factors for the zenith luminance of 188 for snow and clouds in combination and 33 for snow alone were found at this site. The maximum zenith luminance of nearly 250 mcd/m2 measured with snow and clouds is a factor of 1000 higher than the commonly used clear sky reference of 0.25 mcd/m2. Compared with our darkest zenith luminance of 0.07 mcd/m2 measured for overcast conditions in a very remote area, this leads to an overall amplification factor of ca. 3500. Horizontal illuminance measurements show values of up to 0.79 lx, exceeding maximum possible full-moon illuminance levels by more than a factor of two. Additional measurements near the Arctic Circle for clear and overcast conditions are presented and strategies for further studies are discussed. We propose the term “snowglow” to describe the amplification of skyglow by snow with and without clouds.  
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  Series Volume Series Issue Edition  
  ISSN 2313-433X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2699  
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