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Author Rabaza, O.; Galadi-Enriquez, D.; Estrella, A.E.; Dols, F.A. url  doi
openurl 
  Title All-sky brightness monitoring of light pollution with astronomical methods Type Journal Article
  Year 2010 Publication Journal of Environmental Management Abbreviated Journal J Environ Manage  
  Volume 91 Issue 6 Pages 1278-1287  
  Keywords *Astronomy; Calibration; *Environmental Pollutants; *Light  
  Abstract This paper describes a mobile prototype and a protocol to measure light pollution based on astronomical methods. The prototype takes three all-sky images using BVR filters of the Johnson-Cousins astronomical photometric system. The stars are then identified in the images of the Hipparcos and General Catalogue of Photometric Data II astronomical catalogues, and are used as calibration sources. This method permits the measurement of night-sky brightness and facilitates an estimate of which fraction is due to the light up-scattered in the atmosphere by a wide variety of man-made sources. This is achieved by our software, which compares the sky background flux to that of many stars of known brightness. The reduced weight and dimensions of the prototype allow the user to make measurements from virtually any location. This prototype is capable of measuring the sky distribution of light pollution, and also provides an accurate estimate of the background flux at each photometric band.  
  Address (down) Department of Civil Engineering, University of Granada, Severo Ochoa Str. s/n, 18071 Granada, Spain. ovidio@ugr.es  
  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 0301-4797 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:20199844 Approved no  
  Call Number IDA @ john @ Serial 192  
Permanent link to this record
 

 
Author Muheim, R.; Phillips, J.B.; Akesson, S. url  doi
openurl 
  Title Polarized light cues underlie compass calibration in migratory songbirds Type Journal Article
  Year 2006 Publication Science (New York, N.Y.) Abbreviated Journal Science  
  Volume 313 Issue 5788 Pages 837-839  
  Keywords Alaska; *Animal Migration; Animals; Calibration; Cues; *Flight, Animal; Geography; *Light; Magnetics; *Orientation; Seasons; Sparrows/*physiology; Sunlight  
  Abstract Migratory songbirds use the geomagnetic field, stars, the Sun, and polarized light patterns to determine their migratory direction. To prevent navigational errors, it is necessary to calibrate all of these compass systems to a common reference. We show that migratory Savannah sparrows use polarized light cues from the region of sky near the horizon to recalibrate the magnetic compass at both sunrise and sunset. We suggest that skylight polarization patterns are used to derive an absolute (i.e., geographic) directional system that provides the primary calibration reference for all of the compasses of migratory songbirds.  
  Address (down) Department of Animal Ecology, Lund University, Ecology Building, SE-223 62 Lund, Sweden. rmuheim@vt.edu  
  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 0036-8075 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16902138 Approved no  
  Call Number IDA @ john @ Serial 243  
Permanent link to this record
 

 
Author Allik, T.; Ramboyong, L.; Roberts, M.; Walters, M.; Soyka, T.; Dixon, R.; Cho, J. url  doi
openurl 
  Title Enhanced oil spill detection sensors in low-light environments Type Conference Article
  Year 2016 Publication Proc. SPIE 9827, Ocean Sensing and Monitoring VIII, 98270B (May 17, 2016) Abbreviated Journal Proc. SPIE 9827  
  Volume Issue Pages  
  Keywords Instrumentation; Sensors; Cameras; Long wavelength infrared; Short wave infrared radiation; Spectroscopy; Calibration; Remote sensing; Water; Near infrared; Night vision  
  Abstract Although advances have been made in oil spill remote detection, many electro-optic sensors do not provide real-time images, do not work well under degraded visual environments, nor provide a measure of extreme oil thickness in marine environments. A joint program now exists between BSEE and NVESD that addresses these capability gaps in remote sensing of oil spills. Laboratory experiments, calibration techniques, and field tests were performed at Fort Belvoir, Virginia; Santa Barbara, California; and the Ohmsett Test Facility in Leonardo, New Jersey. Weathered crude oils were studied spectroscopically and characterized with LWIR, and low-light-level visible/NIR, and SWIR cameras. We designed and fabricated an oil emulsion thickness calibration cell for spectroscopic analysis and ground truth, field measurements. Digital night vision cameras provided real-time, wide-dynamic-range imagery, and were able to detect and recognize oil from full sun to partial moon light. The LWIR camera provided quantitative oil analysis (identification) for >1 mm thick crude oils both day and night. Two filtered, co-registered, SWIR cameras were used to determine whether oil thickness could be measured in real time. Spectroscopic results revealed that oil emulsions vary with location and weathered state and some oils (e.g., ANS and Santa Barbara seeps) do not show the spectral rich features from archived Deep Water Horizon hyperspectral data. Multi-sensor imagery collected during the 2015 USCG Airborne Oil Spill Remote Sensing and Reporting Exercise and the design of a compact, multiband imager are discussed.  
  Address (down) Active EO Inc.  
  Corporate Author Thesis  
  Publisher SPIE Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1475  
Permanent link to this record
 

 
Author Letu, H.; Hara, M.; Tana, G.; Nishio, F. url  doi
openurl 
  Title A Saturated Light Correction Method for DMSP/OLS Nighttime Satellite Imagery Type Journal Article
  Year 2012 Publication IEEE Transactions on Geoscience and Remote Sensing Abbreviated Journal IEEE Trans. Geosci. Remote Sensing  
  Volume 50 Issue 2 Pages 389-396  
  Keywords DMSP-OLS; remote sensing; light at night; radiometry; calibration  
  Abstract Several studies have clarified that electric power consumption can be estimated from the Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) stable light imagery. As digital numbers (DNs) of stable light images are often saturated in the center of city areas, we developed a saturated light correction method for the DMSP/OLS stable light image using the nighttime radiance calibration image of the DMSP/OLS. The comparison between the nonsaturated part of the stable light image for 1999 and the radiance calibration image for 1996-1997 in major areas of Japan showed a strong linear correlation (R2 = 92.73) between the DNs of both images. Saturated DNs of the stable light image could therefore be corrected based on the correlation equation between the two images. To evaluate the new saturated light correction method, a regression analysis is performed between statistic data of electric power consumption from lighting and the cumulative DNs of the stable light image before and after correcting for the saturation effects by the new method, in comparison to the conventional method, which is, the cubic regression equation method. The results show a stronger improvement in the determination coefficient with the new saturated light correction method (R2 = 0.91, P = 1.7 ·10-6 <; 0.05) than with the conventional method (R2 = 0.81, P = 2.6 ·10-6 <; 0.05) from the initial correlation with the uncorrected data (R2 = 0.70, P = 4.5 · 10-6 <; 0.05). The new method proves therefore to be very efficient for saturated light correction.  
  Address (down)  
  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 0196-2892 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 204  
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