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Author Su, Z.; Zhong, X.; Zhang, G.; Li, Y.; He, X.; Wang, Q.; Wei, Z.; He, C.; Li, D.
Title High Sensitive Night-time Light Imaging Camera Design and In-orbit Test of Luojia1-01 Satellite Type Journal Article
Year 2019 Publication Sensors Abbreviated Journal (down) Sensors
Volume 19 Issue 4 Pages 797
Keywords Remote Sensing; Instrumentation
Abstract Luojia1-01 satellite is the first scientific experimental satellite applied for night-time light remote sensing data acquisition, and the payload is an optical camera with high sensitivity, high radiation measurement accuracy and stable elements of interior orientation. At the same time, a special shaped hood is designed, which significantly improved the ability of the camera to suppress stray light. Camera electronics adopts the integrated design of focal plane and imaging processing, which greatly reduces the volume and weight of the system. In this paper, the design of the optical camera is summarized, and the results of in-orbit imaging performance tests are analyzed. The results show that the dynamic modulation transfer function (MTF) of the camera is better than 0.17, and the SNR is better than 35 dB under the condition of 10 lx illuminance and 0.3 reflectivity and all indicators meet the design requirements. The data obtained have been widely applied in many fields such as the process of urbanization, light pollution analysis, marine fisheries detection and military.
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 2215
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Author Bará, S.; Tapia, C.; Zamorano, J.
Title Absolute Radiometric Calibration of TESS-W and SQM Night Sky Brightness Sensors Type Journal Article
Year 2019 Publication Sensors Abbreviated Journal (down) Sensors
Volume 19 Issue 6 Pages 1336
Keywords Instrumentation; calibration; SQM; TESS; photometer; sky brightness
Abstract We develop a general optical model and describe the absolute radiometric calibration of the readings provided by two widely-used night sky brightness sensors based on irradiance-to-frequency conversion. The calibration involves the precise determination of the overall spectral sensitivity of the devices and also the constant G relating the output frequency of the light-to-frequency converter chip to the actual band-weighted and field-of-view averaged spectral radiance incident on the detector (brightness). From these parameters, we show how to define a rigorous astronomical absolute photometric system in which the sensor measurements can be reported in units of magnitudes per square arcsecond with precise physical meaning.
Address Departmento Física Aplicada, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Galicia, Spain; salva.bara(at)usc.es
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 1424-8220 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 2263
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Author Coesfeld, J.; Kuester, T.; Kuechly, H.U.; Kyba, C.C.M.
Title Reducing Variability and Removing Natural Light from Nighttime Satellite Imagery: A Case Study Using the VIIRS DNB Type Journal Article
Year 2020 Publication Sensors Abbreviated Journal (down) Sensors
Volume 20 Issue 11 Pages 3287
Keywords Remote Sensing; Instrumentation
Abstract Temporal variation of natural light sources such as airglow limits the ability of night light sensors to detect changes in small sources of artificial light (such as villages). This study presents a method for correcting for this effect globally, using the satellite radiance detected from regions without artificial light emissions. We developed a routine to define an approximate grid of locations worldwide that do not have regular light emission. We apply this method with a 5 degree equally spaced global grid (total of 2016 individual locations), using data from the Visible Infrared Imaging Radiometer Suite (VIIRS) Day-Night Band (DNB). This code could easily be adapted for other future global sensors. The correction reduces the standard deviation of data in the Earth Observation Group monthly DNB composites by almost a factor of two. The code and datasets presented here are available under an open license by GFZ Data Services, and are implemented in the Radiance Light Trends web application.
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 2988
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Author Shimomura, M.; Yoshida, H.; Fujiuchi, N.; Ariizumi, T.; Ezura, H.; Fukuda, N.
Title Continuous blue lighting and elevated carbon dioxide concentration rapidly increase chlorogenic acid content in young lettuce plants Type Journal Article
Year 2020 Publication Scientia Horticulturae Abbreviated Journal (down) Scientia Horticulturae
Volume 272 Issue Pages 109550
Keywords Plants
Abstract Chlorogenic acid (CGA) is a strong antioxidant that potentially reduces oxidative damage in human cells. In this study, the effects of environmental factors such as photoperiod, light quality and intensity, and CO2 concentration on the growth and CGA content of lettuce (Lactuca sativa L.) were evaluated. CGA content in fresh lettuce increased under high light intensity treatments, doubling in concentration under 200 μmol m−2 s-1 compared to 100 μmol m−2 s-1. Elevated CO2 concentration also increased CGA content in fresh lettuce, quadrupling in concentration when grown at 1000 ppm compared to 400 ppm. Furthermore, there was a compound effect of light intensity and CO2 concentration whereby a light intensity level of 200 μmol m−2 s-1 and CO2 of 1000 ppm produced an even higher concentration of CGA, 199 mg per 100 g of fresh lettuce. Increased CGA concentration because of continuous lighting and elevated CO2 was observed under both fluorescent light and blue LED, but not under red LED treatment. Increased day length also induced higher CGA content in lettuce plants. These results show that continuous lighting, including blue spectrum and elevated CO2 concentration can cause higher CGA accumulation in lettuce plants. The observed increase in CGA content was induced only for 2 days after treatment was initiated. One possible interpretation of the data is that physiological stress caused by excess photosynthesis under continuous lighting results in higher CGA content to protect the plant body from high levels of reactive oxidative species. In addition, blue light and CO2 could be stimulus signals for inducing high CGA accumulation via metabolite changes.
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 0304-4238 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 3090
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Author Duan, H.; Cao, Z.; Shen, M.; Liu, D.; Xiao, Q.
Title Detection of illicit sand mining and the associated environmental effects in China's fourth largest freshwater lake using daytime and nighttime satellite images Type Journal Article
Year 2019 Publication Science of The Total Environment Abbreviated Journal (down) Science of The Total Environment
Volume 647 Issue Pages 606-618
Keywords Remote Sensing; Regulation
Abstract Illegal sand mining activities are rampant in coastal and inland water around the world and result in increased water turbidity, reduced water transparency, damage to fish spawning sites and adverse effects on the health of aquatic ecosystems. However, many sand dredging vessels hide during the day and work at night, rendering conventional monitoring measures ineffective. In this study, illegal sand dredging activities and the associated aquatic environmental effects were investigated in Lake Hongze (the fourth largest freshwater lake in China) using both conventional daytime satellite data, including MODIS/Aqua and Landsat TM/ETM data as well as VIIRS Day/Night Band (DNB) nighttime light (NTL) data, the following results were obtained. (1) The Landsat data revealed that sand dredging vessels first appeared in February 2012 and their number (monthly average: 658) peaked in 2016, and sand dredging stopped after March 2017. (2) The VIIRS NTL data were satisfactory for monitoring nighttime illegal dredging activities, and they more accurately reflected the temporal and spatial distribution characteristics of dredging vessels due to their high frequency. (3) Observations from the MODIS data acquired since 2002 showed three distinct stages of changes in the suspended particulate matter (SPM) concentrations of Lake Hongze that were consistent with the temporal distributions of sand dredging vessels. (4) The contribution of dredging vessels to the increases in SPM concentration was quantitatively determined, and nighttime sand dredging activities were found to have disturbed the waters more significantly. (5) The effectiveness of government measures implemented at various stages to control illegal sand dredging activities were scientifically evaluated. This study provides technological support for government monitoring and the control of illegal sand dredging activities and can serve as a valuable reference for water bodies similar to Lake Hongze worldwide. The evaluation method developed in this study could potentially be applied at a global scale.
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 0048-9697 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 1970
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