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Author Zhang, K.; Zhong, X.; Zhang, G.; Li, D.; Su, Z.; Meng, Y.; Jiang, Y. url  doi
openurl 
  Title Thermal Stability Optimization of the Luojia 1-01 Nighttime Light Remote-Sensing Camera's Principal Distance Type Journal Article
  Year 2019 Publication Sensors (Basel, Switzerland) Abbreviated Journal Sensors (Basel)  
  Volume 19 Issue (up) 5 Pages 990  
  Keywords Instrumentation; Luojia 1-01; nighttime light remote-sensing camera; principal distance; optical-passive athermal design; thermal stability  
  Abstract The instability of the principal distance of the nighttime light remote-sensing camera of the Luojia 1-01 satellite directly affects the geometric accuracy of images, consequently affecting the results of analysis of nighttime light remote-sensing data. Based on the theory of optical passive athermal design, a mathematical model of optical-passive athermal design for principal distance stabilization is established. Positive and negative lenses of different materials and the mechanical structures of different materials are matched to optimize the optical system. According to the index requirements of the Luojia 1-01 camera, an image-telecentric optical system was designed under the guidance of the established mathematical model. In the temperature range of -20 degrees C to +60 degrees C, the principal distance of the system changes from -0.01 mum to +0.28 mum. After on-orbit testing, the geometric accuracy of the designed nighttime light remote-sensing camera is better than 0.20 pixels and less than index requirement of 0.3 pixels, which indicating that the principal distance maintains good stability on-orbit and meets the application requirements of nighttime light remote sensing.  
  Address School of Remote Sensing and Information Engineering, Wuhan University, Wuhan 430079, China. jiangyh@whu.edu.cn  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 1424-8220 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30813556 Approved no  
  Call Number GFZ @ kyba @ Serial 2238  
Permanent link to this record
 

 
Author Barentine, J.C. url  doi
openurl 
  Title Methods for Assessment and Monitoring of Light Pollution around Ecologically Sensitive Sites Type Journal Article
  Year 2019 Publication Journal of Imaging Abbreviated Journal J. Imaging  
  Volume 5 Issue (up) 5 Pages 54  
  Keywords Instrumentation; Skyglow; Remote Sensing; Review  
  Abstract Since the introduction of electric lighting over a century ago, and particularly in the decades following the Second World War, indications of artificial light on the nighttime Earth as seen from Earth orbit have increased at a rate exceeding that of world population growth during the same period. Modification of the natural photic environment at night is a clear and imminent consequence of the proliferation of anthropogenic light at night into outdoor spaces, and with this unprecedented change comes a host of known and suspected ecological consequences. In the past two decades, the conservation community has gradually come to view light pollution as a threat requiring the development of best management practices. Establishing those practices demands a means of quantifying the problem, identifying polluting sources, and monitoring the evolution of their impacts through time. The proliferation of solid-state lighting and the changes to source spectral power distribution it has brought relative to legacy lighting technologies add the complication of color to the overall situation. In this paper, I describe the challenge of quantifying light pollution threats to ecologically-sensitive sites in the context of efforts to conserve natural nighttime darkness, assess the current state of the art in detection and imaging technology as applied to this realm, review some recent innovations, and consider future prospects for imaging approaches to provide substantial support for darkness conservation initiatives around the world.  
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  ISSN 2313-433X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2498  
Permanent link to this record
 

 
Author Hampf, D.; Rowell, G.; Wild, N.; Sudholz, T.; Horns, D.; Tluczykont, M. url  doi
openurl 
  Title Measurement of night sky brightness in southern Australia Type Journal Article
  Year 2011 Publication Advances in Space Research Abbreviated Journal Advances in Space Research  
  Volume 48 Issue (up) 6 Pages 1017-1025  
  Keywords Observatories and site testing; Airglow and aurorae; Photometric, polarimetric, and spectroscopic instrumentation  
  Abstract Night sky brightness is a major source of noise both for Cherenkov telescopes as well as for wide-angle Cherenkov detectors. Therefore, it is important to know the level of night sky brightness at potential sites for future experiments.

The measurements of night sky brightness presented here were carried out at Fowler’s Gap, a research station in New South Wales, Australia, which is a potential site for the proposed TenTen Cherenkov telescope system and the planned wide-angle Cherenkov detector system HiSCORE.

A portable instrument was developed and measurements of the night sky brightness were taken in February and August 2010. Brightness levels were measured for a range of different sky regions and in various spectral bands.

The night sky brightness in the relevant wavelength regime for photomultipliers was found to be at the same level as measured in similar campaigns at the established Cherenkov telescope sites of Khomas, Namibia, and at La Palma. The brightness of dark regions in the sky is about 2 × 1012 photons/(s sr m2) between 300 nm and 650 nm, and up to four times brighter in bright regions of the sky towards the galactic plane. The brightness in V band is 21.6 magnitudes per arcsec2 in the dark regions. All brightness levels are averaged over the field of view of the instrument of about 1.3 × 10−3 sr.

The spectrum of the night sky brightness was found to be dominated by longer wavelengths, which allows to apply filters to separate the night sky brightness from the blue Cherenkov light. The possible gain in the signal to noise ratio was found to be up to 1.2, assuming an ideal low-pass filter.
 
  Address Department of Physics, University of Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany  
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  Series Volume Series Issue Edition  
  ISSN 0273-1177 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 189  
Permanent link to this record
 

 
Author Bierman, A.; Figueiro, M.G.; Rea, M.S. url  doi
openurl 
  Title Measuring and predicting eyelid spectral transmittance Type Journal Article
  Year 2011 Publication Journal of Biomedical Optics Abbreviated Journal J Biomed Opt  
  Volume 16 Issue (up) 6 Pages 067011  
  Keywords Instrumentation; Human Health  
  Abstract The purpose of the present study was to objectively quantify the spectral transmittance of the eyelid. Reported here are data acquired using a technique that was developed to provide practical and accurate measurements of eyelid transmittance across the visible portion of the electromagnetic spectrum. The empirical data were analyzed in terms of the absorption and scattering characteristics of the constituents of skin to develop a method for predicting eyelid transmission. Results showed that the eyelid has a much higher optical density at short wavelengths than previously published. The mean +/- standard deviation (s.d.) optical density of the eyelid from 450 to 650 nm was 2.1 +/- 0.3 with an optical density range among subjects of approximately 1.0. The study results indicate that skin pigmentation is poorly correlated with eyelid transmission; eyelid transmission is most affected by wavelength-independent macromolecules in the eyelid as well as its overall thickness.  
  Address Rensselaer Polytechnic Institute, Lighting Research Center, 21 Union Street, Troy, New York 12180, USA  
  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 1083-3668 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:21721832 Approved no  
  Call Number LoNNe @ kyba @ Serial 1530  
Permanent link to this record
 

 
Author Li, X.; Li, X.; Li, D.; He, X.; Jendryke, M. url  doi
openurl 
  Title A preliminary investigation of Luojia-1 night-time light imagery Type Journal Article
  Year 2019 Publication Remote Sensing Letters Abbreviated Journal Remote Sensing Letters  
  Volume 10 Issue (up) 6 Pages 526-535  
  Keywords Remote Sensing; Instrumentation  
  Abstract Launched on 2 June 2018, Luojia-1 satellite records night-time light imagery at 130 m resolution, which is higher than most of the existing night-time light images to date. This study evaluated radiometric and spatial properties of the Luojia-1 satellite imagery for cities of Los Angeles, Wuhan and Rome as well as the change detection capability for Zunyi city. For the radiometric property, the analysis shows that the Luojia-1 images correlate well with the radiance of the Visible Infrared Imaging Radiometer Suite (VIIRS)’s Day and Night Band (DNB), and that the Luojia-1 images have a wider range of radiance values, as well as higher radiance values (e.g., 40%–90% higher) than the VIIRS DNB images. Using wavelet decomposition and change detection analysis to evaluate spatial property and change detection capability, it was found that the Luojia-1 images provide abundant spatial detail information, with about 20%–54% energy of wavelet component of the images stored in 100–400 m resolutions, and they can help to track the electrification of new roads and buildings at a fine resolution. This study shows that the Luojia-1 images are an effective data source for analysing spatiotemporal distribution of night-time light and its associated socioeconomic attributes.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2150-704X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2199  
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