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Author Zhang, G.; Li, L.; Jiang, Y.; Shen, X.; Li, D.
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
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:30513817 Approved no
Call Number GFZ @ kyba @ Serial 2125
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Author Jiang, W.; He, G.; Long, T.; Guo, H.; Yin, R.; Leng, W.; Liu, H.; Wang, G.
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.
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 1424-8220 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 1997
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Author Boyce, P.R.
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.
Address
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Language Summary Language Original Title
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Notes Approved no
Call Number NC @ ehyde3 @ Serial 2113
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Author Correa-Cano, M.E.; Goettsch, B.; Duffy, J.P.; Bennie, J.; Inger, R.; Gaston, K.J.
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
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 2045-2322 ISBN Medium
Area Expedition Conference
Notes PMID:29531261; PMCID:PMC5847551 Approved no
Call Number GFZ @ kyba @ Serial 1824
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Author Linden, B.; Huisman, J.; Rinkevich, B.
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
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 2045-2322 ISBN Medium
Area Expedition Conference
Notes PMID:29618779 Approved no
Call Number GFZ @ kyba @ Serial 1849
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