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Author Zhang, K.; Zhong, X.; Zhang, G.; Li, D.; Su, Z.; Meng, Y.; Jiang, Y.
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 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
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:30813556 Approved no
Call Number GFZ @ kyba @ Serial (down) 2238
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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 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 (down) 2215
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Author Fiorentin, P.; Boscaro, F.
Title A method for measuring the light output of video advertising reproduced by LED billboards Type Journal Article
Year 2019 Publication Measurement Abbreviated Journal Measurement
Volume 138 Issue Pages 25-33
Keywords Lighting; Energy; Instrumentation; Planning; Light-emitting diode displays; Photometry; Video recording; Image analysis; CCD image sensors; Luminance; Glare
Abstract Improving knowledge of the light output of digital billboards is important to better assess their effect on driver distraction when they are installed along roads. In this work the emission of an LED based billboard is measured when playing advertising video-clips. In particular the average and the maximum values of the luminance are evaluated. The same video-clips are also analyzed when shown on an LCD monitor, aiming at separating the variability of the videos and of the playing device. The results allow to evaluate an utilization factor of the billboard: the videos have an average luminance around 11% and a peak luminance of 35% of the maximum luminance obtainable from the billboard. The power consumption of the billboard is measured, aside the photometric analysis. The luminance of the device are found linearly dependent on both the power and the effective current absorbed by the device from the grid, with a discrepancy within 6%. It could be a useful information for billboard manufacturers to qualify their product when they do not own photometric instruments.
Address Department of Industrial Engineering, University of Padova, Padova, Italy; pietro.fiorentin(at)unipd.it
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0263-2241 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial (down) 2214
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Author Tauc, M.J.; Fristrup, K.M.; Repasky, K.S.; Shaw, J.A.
Title Field demonstration of a wing-beat modulation lidar for the 3D mapping of flying insects Type Journal Article
Year 2019 Publication OSA Continuum Abbreviated Journal OSA Continuum
Volume 2 Issue 2 Pages 332
Keywords Instrumentation; Animals
Abstract We describe a wing-beat modulation lidar system designed for the 3D mapping of flying insects in ecological or entomological studies. To better understand the signals from this instrument, we analyzed simulated signals to identify how they were affected by various imperfections, such as variations in the spacing and amplitude of each individual wing-beat reflection. In addition, a radiometric model was used to estimate signal-to-noise ratio to gain insight into the relationships between the optical system design and insect parameters (e.g., wing size, reflectivity, or diffusivity).
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 2578-7519 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial (down) 2209
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Author Li, X.; Li, X.; Li, D.; He, X.; Jendryke, M.
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 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.
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 2150-704X ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial (down) 2199
Permanent link to this record