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Author Zhang, G.; Li, L.; Jiang, Y.; Shen, X.; Li, D. url  doi
openurl 
  Title On-Orbit Relative Radiometric Calibration of the Night-Time Sensor of the LuoJia1-01 Satellite Type Journal Article
  Year 2018 Publication (down) Sensors (Basel, Switzerland) Abbreviated Journal Sensors (Basel)  
  Volume 18 Issue 12 Pages  
  Keywords Instrumentation; Remote Sensing  
  Abstract The LuoJia1-01 satellite can acquire high-resolution, high-sensitivity nighttime light data for night remote sensing applications. LuoJia1-01 is equipped with a 4-megapixel CMOS sensor composed of 2048 x 2048 unique detectors that record weak nighttime light on Earth. Owing to minute variations in manufacturing and temporal degradation, each detector's behavior varies when exposed to uniform radiance, resulting in noticeable detector-level errors in the acquired imagery. Radiometric calibration helps to eliminate these detector-level errors. For the nighttime sensor of LuoJia1-01, it is difficult to directly use the nighttime light data to calibrate the detector-level errors, because at night there is no large-area uniform light source. This paper reports an on-orbit radiometric calibration method that uses daytime data to estimate the relative calibration coefficients for each detector in the LuoJia1-01 nighttime sensor, and uses the calibrated data to correct nighttime data. The image sensor has a high dynamic range (HDR) mode, which is optimized for day/night imaging applications. An HDR image can be constructed using low- and high-gain HDR images captured in HDR mode. Hence, a day-to-night radiometric reference transfer model, which uses daytime uniform calibration to calibrate the detector non-uniformity of the nighttime sensor, is herein built for LuoJia1-01. Owing to the lack of calibration equipment on-board LuoJia1-01, the dark current of the nighttime sensor is calibrated by collecting no-light desert images at new moon. The results show that in HDR mode (1) the root mean square of mean for each detector in low-gain (high-gain) images is better than 0.04 (0.07) in digital number (DN) after dark current correction; (2) the DN relationship between low- and high-gain images conforms to the quadratic polynomial mode; (3) streaking metrics are better than 0.2% after relative calibration; and (4) the nighttime sensor has the same relative correction parameters at different exposure times for the same gain parameters.  
  Address State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan 430079, China. drli@whu.edu.cn  
  Corporate Author Thesis  
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  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:30513817 Approved no  
  Call Number GFZ @ kyba @ Serial 2125  
Permanent link to this record
 

 
Author Jiang, W.; He, G.; Long, T.; Guo, H.; Yin, R.; Leng, W.; Liu, H.; Wang, G. url  doi
openurl 
  Title Potentiality of Using Luojia 1-01 Nighttime Light Imagery to Investigate Artificial Light Pollution Type Journal Article
  Year 2018 Publication (down) Sensors Abbreviated Journal Sensors  
  Volume 18 Issue 9 Pages 2900  
  Keywords Remote Sensing; Instrumentation  
  Abstract The successful launch of Luojia 1-01 complements the existing nighttime light data with a high spatial resolution of 130 m. This paper is the first study to assess the potential of using Luojia 1-01 nighttime light imagery for investigating artificial light pollution. Eight Luojia 1-01 images were selected to conduct geometric correction. Then, the ability of Luojia 1-01 to detect artificial light pollution was assessed from three aspects, including the comparison between Luojia 1-01 and the Suomi National Polar-Orbiting Partnership Visible Infrared Imaging Radiometer Suite (NPP-VIIRS), the source of artificial light pollution and the patterns of urban light pollution. Moreover, the advantages and limitations of Luojia 1-01 were discussed. The results showed the following: (1) Luojia 1-01 can detect a higher dynamic range and capture the finer spatial details of artificial nighttime light. (2) The averages of the artificial light brightness were different between various land use types. The brightness of the artificial light pollution of airports, streets, and commercial services is high, while dark areas include farmland and rivers. (3) The light pollution patterns of four cities decreased away from the urban core and the total light pollution is highly related to the economic development. Our findings confirm that Luojia 1-01 can be effectively used to investigate artificial light pollution. Some limitations of Luojia 1-01, including its spectral range, radiometric calibration and the effects of clouds and moonlight, should be researched in future studies.  
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  Series Editor Series Title Abbreviated Series Title  
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  ISSN 1424-8220 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1997  
Permanent link to this record
 

 
Author Boyce, P.R. url  doi
openurl 
  Title The Present and Future of Lighting Research Type Journal Article
  Year 2018 Publication (down) SDAR* Journal of Sustainable Design & Applied Research Abbreviated Journal  
  Volume 6 Issue 1 Pages  
  Keywords Commentary; Lighting; Vision; Human Health  
  Abstract The aim of this paper is to consider where lighting research is today and what its future might be. There is little doubt that, today, lighting research is an active field. A brief review of the topics being studied reveals that they range from residual studies on visibility and visual discomfort, through attempts to identify the influence of lighting on factors beyond visibility such as mood and behaviour, to the whole new field of light and health. But activity alone is not enough to justify a future. For lighting research to have a future it is necessary for it to

be influential. To become influential, research needs to focus its attention on outcomes that matter to people and the elements of those outcomes on which lighting is known to have a major influence. Further, researchers will have to be determined to overcome the barriers to changing lighting practice. By doing this, lighting research may change the world for the better, to be an important topic, not an irrelevance.
 
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  Notes Approved no  
  Call Number NC @ ehyde3 @ Serial 2113  
Permanent link to this record
 

 
Author Correa-Cano, M.E.; Goettsch, B.; Duffy, J.P.; Bennie, J.; Inger, R.; Gaston, K.J. url  doi
openurl 
  Title Erosion of natural darkness in the geographic ranges of cacti Type Journal Article
  Year 2018 Publication (down) Scientific Reports Abbreviated Journal Sci Rep  
  Volume 8 Issue 1 Pages 4347  
  Keywords Plants; Remote Sensing  
  Abstract Naturally dark nighttime environments are being widely eroded by the introduction of artificial light at night (ALAN). The biological impacts vary with the intensity and spectrum of ALAN, but have been documented from molecules to ecosystems. How globally severe these impacts are likely to be depends in large part on the relationship between the spatio-temporal distribution of ALAN and that of the geographic ranges of species. Here, we determine this relationship for the Cactaceae family. Using maps of the geographic ranges of cacti and nighttime stable light composite images for the period 1992 to 2012, we found that a high percentage of cactus species were experiencing ALAN within their ranges in 1992, and that this percentage had increased by 2012. For almost all cactus species (89.7%) the percentage of their geographic range that was lit increased from 1992-1996 to 2008-2012, often markedly. There was a significant negative relationship between the species richness of an area, and that of threatened species, and the level of ALAN. Cacti could be particularly sensitive to this widespread and ongoing intrusion of ALAN into their geographic ranges, especially when considering the potential for additive and synergistic interactions with the impacts of other anthropogenic pressures.  
  Address Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall, TR10 9FE, UK  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2045-2322 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:29531261; PMCID:PMC5847551 Approved no  
  Call Number GFZ @ kyba @ Serial 1824  
Permanent link to this record
 

 
Author Linden, B.; Huisman, J.; Rinkevich, B. url  doi
openurl 
  Title Circatrigintan instead of lunar periodicity of larval release in a brooding coral species Type Journal Article
  Year 2018 Publication (down) Scientific Reports Abbreviated Journal Sci Rep  
  Volume 8 Issue 1 Pages 5668  
  Keywords Animals  
  Abstract Larval release by brooding corals is often assumed to display lunar periodicity. Here, we show that larval release of individual Stylophora pistillata colonies does not comply with the assumed tight entrainment by the lunar cycle, and can better be classified as a circatrigintan pattern. The colonies exhibited three distinct reproductive patterns, characterized by short intervals, long intervals and no periodicity between reproductive peaks, respectively. Cross correlation between the lunar cycle and larval release of the periodic colonies revealed an approximately 30-day periodicity with a variable lag of 5 to 10 days after full moon. The observed variability indicates that the lunar cycle does not provide a strict zeitgeber. Other factors such as water temperature and solar radiation did not correlate significantly with the larval release. The circatrigintan patterns displayed by S. pistillata supports the plasticity of corals and sheds new light on discussions on the fecundity of brooding coral species.  
  Address Israel Oceanographic and Limnological Research, National Institute of Oceanography, Tel-Shikmona, P.O. Box 8030, Haifa, 31080, Israel  
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  Series Volume Series Issue Edition  
  ISSN 2045-2322 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:29618779 Approved no  
  Call Number GFZ @ kyba @ Serial 1849  
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