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Author Figura, J.; Haughwout, C.; Cahoy, K.; Welle, R.; Hardy, B.; Pack, D.; Bosh, A. url  openurl
  Title Initial Demonstration of an Uplink LED Beacon to a Low Earth Orbiting CubeSat Type Journal Article
  Year 2018 Publication Journal of Small Satellites Abbreviated Journal (up)  
  Volume 7 Issue 2 Pages 719-732  
  Keywords Remote Sensing  
  Abstract In this study, an uplink light-emitting diode (LED) beacon that can enable a CubeSat to locate a laser communication ground station was designed, constructed, and tested, and detection of the beacon from low Earth orbit (LEO) with a CMOS camera on the AeroCube-5 CubeSat was demonstrated. The LED beacon described is an alternative to the near-infrared laser beacons commonly used in laser communication systems, and has the potential to be cheaper, easier to point, and to require less regulatory coordination than a laser beacon, while performing the same function. An optical design is detailed, consisting of an array of 80 green LEDs with a center wavelength of 528 nm, producing 15.9 watts of free-space optical power, focused to a beamwidth of 8.12 degrees full-widthhalf-max (FWHM). A link budget is presented that shows the beacon is detectable by a CubeSat-mounted camera with a 7.9 mm diameter aperture and a silicon CMOS detector. A prototype beacon comprised of an LED array, focusing optics, thermal control, and tracking mechanisms was designed and constructed, and laboratory measurements of the beam profile and optical power of the prototype beacon using an optical power meter are presented herein. A field test is also described, in which the beacon was deployed at Wallace Astrophysical Observatory in the early morning of May 15, 2017 and imaged with a camera on AeroCube-5. The array is successfully identified in a sequence of five images taken by the CubeSat, demonstrating the viability of LED uplink beacons with CubeSat imagers.  
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  Notes Approved no  
  Call Number NC @ ehyde3 @ Serial 2108  
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Author Min, B.; O'Keeffe, Z.; Zhang, F. url  doi
openurl 
  Title Whose Power Gets Cut? Using High-Frequency Satellite Images to Measure Power Supply Irregularity Type Book Whole
  Year 2017 Publication Policy Research Working Papers Abbreviated Journal (up)  
  Volume Issue Pages  
  Keywords Remote Sensing  
  Abstract In many parts of the developing world, access to electricity is uneven and inconsistent, characterized by frequent and long hours of power outages. Many countries now engage in systematic load shedding because of persistent power shortages. When and where electricity is provided can have important impacts on welfare and growth. But quantifying those impacts is difficult because utility-level data on power outages are rarely available and not always reliable. This paper introduces a new method of tracking power outages from outer space. This measure identifies outage-prone areas by detecting excess fluctuations in light outputs. To develop these measures, the study processed the complete historical archive of sub-orbital Defense Meteorological Satellite Program's Operational Linescan System (DMSP-OLS) nighttime imagery captured over South Asia on every night since 1993. The analysis computes annual estimates of the Power Supply Irregularity index for all 600,000 villages in India from 1993 to 2013. The Power Supply Irregularity index measures are consistent with ground-based measures of power supply reliability from the Indian Human Development Survey, and with feeder-level outage data from one of the largest utilities in India. The study's methods open new opportunities to study the determinants of power outages as well as their impacts on welfare.  
  Address  
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  Publisher The World Bank Place of Publication Editor  
  Language Summary Language Original Title  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number NC @ ehyde3 @ Serial 2109  
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Author Boyce, P.R. url  doi
openurl 
  Title The Present and Future of Lighting Research Type Journal Article
  Year 2018 Publication SDAR* Journal of Sustainable Design & Applied Research Abbreviated Journal (up)  
  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.
 
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  Call Number NC @ ehyde3 @ Serial 2113  
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Author Zapata, M.J.; Sullivan, S.M.P.; Gray, S.M. url  doi
openurl 
  Title Artificial Lighting at Night in Estuaries—Implications from Individuals to Ecosystems Type Journal Article
  Year 2018 Publication Estuaries and Coasts Abbreviated Journal (up)  
  Volume In press Issue Pages  
  Keywords Animals; Ecology  
  Abstract Artificial lighting at night (ALAN) produced by urban, industrial, and roadway lighting, as well as other sources, has dramatically increased in recent decades, especially in coastal environments that support dense human populations. Artificial “lightscapes” are characterized by distinct spatial, temporal, and spectral patterns that can alter natural patterns of light and dark with consequences across levels of biological organization. At the individual level, ALAN can elicit a suite of physiological and behavioral responses associated with light-mediated processes such as diel activity patterns and predator-prey interactions. ALAN has also been shown to modify community composition and trophic structure, with implications for ecosystem-level processes including primary productivity, nutrient cycling, and the energetic linkages between aquatic and terrestrial systems. Here, we review the state of the science relative to the impacts of ALAN on estuaries, which is an important step in assessing the long-term sustainability of coastal regions. We first consider how multiple properties of ALAN (e.g., intensity and spectral content) influence the interaction between physiology and behavior of individual estuarine biota (drawing from studies on invertebrates, fishes, and birds). Second, we link individual- to community- and ecosystem-level responses, with a focus on the impacts of ALAN on food webs and implications for estuarine ecosystem functions. Coastal aquatic communities and ecosystems have been identified as a key priority for ALAN research, and a cohesive research framework will be critical for understanding and mitigating ecological consequences.  
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  Call Number NC @ ehyde3 @ Serial 2116  
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Author Rea, M.; Skinner, N.; Bullough, J. url  doi
openurl 
  Title A Novel Barricade Warning Light System Using Wireless Communications Type Journal Article
  Year 2018 Publication SAE Technical Paper 2018-01-5036 Abbreviated Journal (up)  
  Volume In press Issue Pages  
  Keywords Lighting; Safety  
  Abstract Workers in construction and transportation sectors are at increased risk for work-related injuries and fatalities by nearby traffic. Barricade-mounted warning lights meeting current specifications do not always provide consistent and adequate visual guidance to drivers and can contribute to glare and reduced safety. Through an implementation of sensors and wireless communications, a novel, intelligent set of warning lights and a tablet-based interface were developed. The lights modulate between 100% and 10% of maximum intensity rather than between 100% and off in order to improve visual guidance and adjust their overall intensity based on ambient conditions. The lights can be synchronized or operated in sequential flash patterns at any frequency between 1 and 4 Hz, and sequential patterns automatically update based on global positioning satellite (GPS) locations displayed in the control interface. A successful field demonstration of the system verified that its functions were viewed favorably by transportation safety personnel.  
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  Notes Approved no  
  Call Number NC @ ehyde3 @ Serial 2117  
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