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Author Kocifaj, M.; Solano Lamphar, H.A. url  doi
openurl 
  Title Angular Emission Function of a City and Skyglow Modeling: A Critical Perspective Type Journal Article
  Year 2016 Publication (down) Publications of the Astronomical Society of the Pacific Abbreviated Journal Pasp  
  Volume 128 Issue 970 Pages 124001  
  Keywords Skyglow  
  Abstract The radiative transfer equation (RTE) is a common approach to solving the transfer of electromagnetic energy in heterogeneous disperse media, such as atmospheric environment. One-dimensional RTE is a linear boundary value problem that is well suited to plane-parallel atmosphere with no diffuse intensity entering the top of the atmosphere. In nighttime regime, the ground-based light sources illuminate the atmosphere at its bottom interface. However, the light-pollution models conventionally use radiant intensity function rather than radiance. This might potentially result in a number of misconceptions. We focused on similarities and fundamental differences between both functions and clarified distinct consequences for the modeling of skyglow from finite-sized and semi-infinite light-emitting flat surfaces. Minimum requirements to be fulfilled by a City Emission Function (CEF) are formulated to ensure a successful solution of standard and inverse problems. It has been shown that the horizon radiance of a flat surface emitting in accordance with Garstang's function (GEF) would exceed any limit, meaning that the GEF is not an appropriate tool to model skyglow from distant sources. We developed two alternative CEFs to remedy this problem through correction of direct upward emissions; the most important strengths of the modified CEFs are detailed in this paper. Numerical experiments on sky luminance under well-posed and ill-posed boundary conditions were made for two extreme uplight fractions (F) and for three discrete distances from the city edge. The errors induced by replacing radiance with radiant intensity function in the RTE are generally low (15%–30%) if F is as large as 0.15, but alteration of the luminance may range over 1–3 orders of magnitude if F approaches zero. In the latter case, the error margin can increase by a factor of 10–100 or even 1000, even if the angular structure of luminance patterns suffers only weak changes. This is why such a shift in luminance magnitudes can be mistakenly interpreted as the effect of inaccurate estimate of lumens per head of the population rather than the effect of cosine distortion due to ill-posed inputs to the RTE. For that reason, a thorough revision (and/or remediation) of theoretical and computational models is suggested.  
  Address  
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  Series Volume Series Issue Edition  
  ISSN 0004-6280 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number LoNNe @ kyba @ Serial 1564  
Permanent link to this record
 

 
Author Zielinska-Dabkowska, K. url  openurl
  Title Case study of “Walk”: a video installation integrated into the facade of a store in Zurich/CH Type Journal Article
  Year 2016 Publication (down) Professional Lighting Design Abbreviated Journal Prof Lighting Des  
  Volume Issue 101 Pages 52-58  
  Keywords Lighting; planning; commentary  
  Abstract With the rapid development of solid state lighting technology and the availability of LED light sources, coupled with the benefits they offer such as energy efficiency, long lifespan and the fact that they can be controlled and programmed, we are now finding LEDs being more widely used for animated advertising. In spite of the pace at which SSL is developing, or perhaps because of this, there is a distinct lack of evaluation guidelines or recommendations for professional designers. It is therefore essential that more research is carried out on this issue on an international scale, and that experts in the field get their heads together in order to formulate some basic guidelines that can be applied in practice.  
  Address Faculty of Architecture & Design, Hochschule Wismar, Wismar, Germany; k.zielinska-dabkowska(at)hs-wismar.de  
  Corporate Author Thesis  
  Publisher Verlag 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 1479  
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Author Scheffler, T.; Kyba, C.C.M. url  openurl
  Title Measuring Social Jetlag in Twitter Data Type Conference Article
  Year 2016 Publication (down) Proceedings of the Tenth International AAAI Conference on Web and Social Media (ICWSM 2016) Abbreviated Journal  
  Volume Issue Pages 675-678  
  Keywords Human Health; Sunlight; Society  
  Abstract Social constraints have replaced the natural cycle of light and darkness as the main determinant of wake-up and activity times for many people. In this paper we show how Twitter activity can be used as a source of large-scale, naturally occurring data for the study of circadian rhythm in humans. Our year-long initial study is based on almost 1.5 million observations by over 200,000 users. The progression of the onset of Twitter activity times on free days in the course of the year is consistent with previous survey-based research on wake

times. We show that the difference in wake-up time (implicating lack of sleep) on weekdays compared to Sundays is between 1 hour and over 2 hours depending on the time of year. The data also supports the assertion that Daylight Saving Time greatly disrupts the easing of social jetlag in the Spring transition.
 
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  ISSN ISBN Medium  
  Area Expedition Conference ICWSM 2016  
  Notes Approved no  
  Call Number LoNNe @ kyba @ Serial 1453  
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Author Lucas, M.A.; Chahl, J.S. url  doi
openurl 
  Title Challenges for biomimetic night time sky polarization navigation Type Conference Article
  Year 2016 Publication (down) Proceedings of the SPIE Abbreviated Journal Proc SPIE  
  Volume 9797 Issue Pages  
  Keywords Animals; detection of light; biology; polarization; navigation  
  Abstract Studies on some species of insects have shown them to use the polarization pattern cast by the moon in the night sky to control heading. Additional heading cues are of value to autonomous systems, since the earth’s magnetic field is not uniform, often not available and is substantially modified by local phenomena. In addition to the required low-light sensitivity of a night time polarization compass, additional complexities caused by the relative intensity of terrestrial sources must be overcome. We will show that the end result will tend to be a less reliable compass than the equivalent day time polarization device.  
  Address Univ. of South Australia, Australia  
  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 1430  
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Author ffrench-Constant, R.; Somers-Yeates, R.; Bennie, J.; Economou, T.; Hodgson, D.; Spalding, A.; McGregor, P. url  doi
openurl 
  Title Light pollution is associated with earlier tree budburst across the United Kingdom Type Journal Article
  Year 2016 Publication (down) Proceedings of the Royal Society B: Biological Sciences Abbreviated Journal Proc Roy Soc B Biol Sci  
  Volume 283 Issue 1833 Pages 1-9  
  Keywords Plants; light pollution, phenology, species interactions, tree budburst, temperature, urban heat islands; United Kingdom  
  Abstract The ecological impact of night-time lighting is of concern because of its well-demonstrated effects on animal behaviour. However, the potential of light pollution to change plant phenology and its corresponding knock-on effects on associated herbivores are less clear. Here, we test if artificial lighting can advance the timing of budburst in trees. We took a UK-wide 13 year dataset of spatially referenced budburst data from four deciduous tree species and matched it with both satellite imagery of night-time lighting and average spring temperature. We find that budburst occurs up to 7.5 days earlier in brighter areas, with the relationship being more pronounced for later-budding species. Excluding large urban areas from the analysis showed an even more pronounced advance of budburst, confirming that the urban ‘heat-island’ effect is not the sole cause of earlier urban budburst. Similarly, the advance in budburst across all sites is too large to be explained by increases in temperature alone. This dramatic advance of budburst illustrates the need for further experimental investigation into the impact of artificial night-time lighting on plant phenology and subsequent species interactions. As light pollution is a growing global phenomenon, the findings of this study are likely to be applicable to a wide range of species interactions across the world.  
  Address Centre for Ecology and Conservation, and 2 Environment and Sustainability Institute, University of Exeter, Penryn TR10 9EZ, UK; rf222(at)exeter.ac.uk  
  Corporate Author Thesis  
  Publisher Royal Society Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
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  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1472  
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