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Author Fu, D.; Xia, X.; Duan, M.; Zhang, X.; Li, X.; Wang, J.; Liu, J. url  doi
openurl 
  Title Mapping nighttime PM 2.5 from VIIRS DNB using a linear mixed-effect model Type Journal Article
  Year 2018 Publication Atmospheric Environment Abbreviated Journal Atmospheric Environment  
  Volume 178 Issue Pages 214-222  
  Keywords Remote Sensing  
  Abstract Estimation of particulate matter with aerodynamic diameter less than 2.5 μm (PM2.5) from daytime satellite aerosol products is widely reported in the literature; however, remote sensing of nighttime surface PM2.5 from space is very limited. PM2.5 shows a distinct diurnal cycle and PM2.5 concentration at 1:00 local standard time (LST) has a linear correlation coefficient (R) of 0.80 with daily-mean PM2.5. Therefore, estimation of nighttime PM2.5 is required toward an improved understanding of temporal variation of PM2.5 and its effects on air quality. Using data from the Day/Night Band (DNB) of the Visible Infrared Imaging Radiometer Suite (VIIRS) and hourly PM2.5 data at 35 stations in Beijing, a mixed-effect model is developed here to estimate nighttime PM2.5 from nighttime light radiance measurements based on the assumption that the DNB-PM2.5 relationship is constant spatially but varies temporally. Cross-validation showed that the model developed using all stations predict daily PM2.5 with mean determination coefficient (R2) of 0.87 ±± 0.12, 0.83 ±0.10±0.10, 0.87 ±± 0.09, 0.83 ±± 0.10 in spring, summer, autumn and winter. Further analysis showed that the best model performance was achieved in urban stations with average cross-validation R2 of 0.92. In rural stations, DNB light signal is weak and was likely smeared by lunar illuminance that resulted in relatively poor estimation of PM2.5. The fixed and random parameters of the mixed-effect model in urban stations differed from those in suburban stations, which indicated that the assumption of the mixed-effect model should be carefully evaluated when used at a regional scale.  
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  Corporate Author Thesis  
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  Language (up) Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1352-2310 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number LoNNe @ kyba @ Serial 1814  
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Author Ma, T.; Yin, Z.; Zhou, A. url  doi
openurl 
  Title Delineating Spatial Patterns in Human Settlements Using VIIRS Nighttime Light Data: A Watershed-Based Partition Approach Type Journal Article
  Year 2018 Publication Remote Sensing Abbreviated Journal Remote Sensing  
  Volume 10 Issue 3 Pages 465  
  Keywords Remote Sensing  
  Abstract As an informative proxy measure for a range of urbanization and socioeconomic variables, satellite-derived nighttime light data have been widely used to investigate diverse anthropogenic activities in human settlements over time and space from the regional to the national scale. With a higher spatial resolution and fewer over-glow and saturation effects, nighttime light data derived from the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument with day/night band (DNB), which is on the Suomi National Polar-Orbiting Partnership satellite (Suomi-NPP), may further improve our understanding of spatiotemporal dynamics and socioeconomic activities, particularly at the local scale. Capturing and identifying spatial patterns in human settlements from VIIRS images, however, is still challenging due to the lack of spatially explicit texture characteristics, which are usually crucial for general image classification methods. In this study, we propose a watershed-based partition approach by combining a second order exponential decay model for the spatial delineation of human settlements with VIIRS-derived nighttime light images. Our method spatially partitions the human settlement into five different types of sub-regions: high, medium-high, medium, medium-low and low lighting areas with different degrees of human activity. This is primarily based on the local coverage of locally maximum radiance signals (watershed-based) and the rank and magnitude of the nocturnal radiance signal across the whole region, as well as remotely sensed building density data and social media-derived human activity information. The comparison results for the relationship between sub-regions with various density nighttime brightness levels and human activities, as well as the densities of different types of interest points (POIs), show that our method can distinctly identify various degrees of human activity based on artificial nighttime radiance and ancillary data. Furthermore, the analysis results across 99 cities in 10 urban agglomerations in China reveal inter-regional variations in partition thresholds and human settlement patterns related to the urban size and form. Our partition method and relative results can provide insight into the further application of VIIRS DNB nighttime light data in spatially delineated urbanization processes and socioeconomic activities in human settlements.  
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  Language (up) Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2072-4292 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1820  
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Author Nagare, R.; Plitnick, B.; Figueiro, M. url  doi
openurl 
  Title Effect of exposure duration and light spectra on nighttime melatonin suppression in adolescents and adults Type Journal Article
  Year 2018 Publication Lighting Research & Technology Abbreviated Journal Lighting Research & Technology  
  Volume 51 Issue 4 Pages 530-543  
  Keywords Human Health  
  Abstract This study investigated how light exposure duration affects melatonin suppression, a well-established marker of circadian phase, and whether adolescents (13–18 years) are more sensitive to short-wavelength (blue) light than adults (32–51 years). Twenty-four participants (12 adolescents, 12 adults) were exposed to three lighting conditions during successive 4-h study nights that were separated by at least one week. In addition to a dim light (<5 lux) control, participants were exposed to two light spectra (warm (2700 K) and cool (5600 K)) delivering a circadian stimulus of 0.25 at eye level. Repeated measures analysis of variance revealed a significant main effect of exposure duration, indicating that a longer duration exposure suppressed melatonin to a greater degree. The analysis further revealed a significant main effect of spectrum and a significant interaction between spectrum and participant age. For the adolescents, but not the adults, melatonin suppression was significantly greater after exposure to the 5600 K intervention (43%) compared to the 2700 K intervention (29%), suggesting an increased sensitivity to short-wavelength radiation. These results will be used to extend the model of human circadian phototransduction to incorporate factors such as exposure duration and participant age to better predict effective circadian stimulus.  
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  Language (up) 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 GFZ @ kyba @ Serial 1821  
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Author Posch, T.; Binder, F.; Puschnig, J. url  doi
openurl 
  Title Systematic measurements of the night sky brightness at 26 locations in Eastern Austria Type Journal Article
  Year 2018 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer  
  Volume 211 Issue Pages 144-165  
  Keywords Skyglow  
  Abstract We present an analysis of the zenithal night sky brightness (henceforth: NSB) measurements at 26 locations in Eastern Austria focussing on the years 2015-2016, both during clear and cloudy to overcast nights. All measurements have been performed with ’Sky Quality Meters’ (SQMs). For some of the locations, simultaneous aerosol content measurements are available, such that we were able to find a correlation between light pollution and air pollution at those stations. For all locations, we examined the circalunar periodicity of the NSB, seasonal variations as well as long-term trends in the recorded light pollution. The latter task proved difficult, however, due to varying meteorological conditions, potential detector ’aging’ and other effects. For several remote locations, a darkening of the overcast night sky by up to 1 magnitude is recorded – indicating a very low level of light pollution –, while for the majority of the examined locations, a brightening of the night sky by up to a factor of 15 occurs due to clouds. We present suitable ways to plot and analyze huge long-term NSB datasets, such as mean-NSB histograms, circalunar, annual (’hourglass’) and cumulative (’jellyfish’) plots. We show that five of the examined locations reach sufficiently low levels of light pollution – with NSB values down to 21.8 magSQM/arcsec2 – as to allow the establishment of dark sky reserves, even to the point of reaching the ’gold tier’ defined by the International Dark Sky Association. Based on the ’hourglass’ plots, we find a strong circalunar periodicity of the NSB in small towns and villages ( <  5.000 inhabitants), with amplitudes of of up to 5 magnitudes. Using the ’jellyfish’ plots, on the other hand, we demonstrate that the examined city skies brighten by up to 3 magnitudes under cloudy conditions, which strongly dominate in those cumulative data representations. Nocturnal gradients of the NSB of 0.0–0.14 magSQM/arcsec2/hr are found. The long-term development of the night sky brightness was evaluated based on the 2012-17 data for one of our sites, possibly indicating a slight ( 2%) decrease of the mean zenithal NSB at the Vienna University Observatory.  
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  Language (up) 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 1825  
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Author Ngarambe, Jack; Kim, Gon url  doi
openurl 
  Title Sustainable Lighting Policies: The Contribution of Advertisement and Decorative Lighting to Local Light Pollution in Seoul, South Korea Type Journal Article
  Year 2018 Publication Sustainability Abbreviated Journal Sustainability  
  Volume 10 Issue 4 Pages 1007  
  Keywords Lighting; Regulation  
  Abstract We carried out field measurements to determine the contribution of advertisement and decorative lighting to local light pollution in Seoul. We used the lighting limits set by the “Light Pollution Prevention Act”, which regulates light pollution, as measuring criteria. Our results show that both advertisement and decorative lighting are significant contributors to local light pollution in Seoul. Thirty percent of advertisement lighting measured in our study areas exceeded the legal limits. Moreover, we found that certain types of advertisement lighting are more likely to cause light pollution than the others. In addition, 73% of the decorative lighting found in our sample areas exceeded the legal limits. Based on our findings, we suggest that local light pollution policies establish a curfew time when all advertisement and decorative lighting must be completely turned off. Such an approach is essential in reducing lighting levels in outdoor environments. Furthermore, it lessens the burden on law enforcement personnel, who otherwise must ensure that advertisement and decorative lighting levels are kept within the legal limits. In light of the ongoing debate over the role of lighting in public well-being and the sustainability of cities, the present study provides a discussion on the status and management policy of light pollution caused by advertisement and decorative lighting.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language (up) Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2071-1050 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1829  
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