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Author Treanor, P. J. url  openurl
  Title A simple propagation law for artificial night-sky illumination Type Journal Article
  Year 1973 Publication The Observatory Abbreviated Journal  
  Volume 93 Issue Pages 117-120  
  Keywords Skyglow  
  Abstract The problem of locating new large astronomical observatories in sites which have a suitably dark night sky (artificial excess of the order of omi) is becoming increasingly difficult in Europe and the United States, on account of extensive urban development, the high luminous efficiency of modern discharge lighting, and the scattering of light in an atmosphere contaminated by aerosols. To investigate the artificial illumination of the sky over large regions on the basis of necessarily limited observations, one needs an expression for the zenith brightness produced by towns of known site and distance.

The exact derivation of such a law is exceedingly complex, involving the computation of the radiation transfer in an atmosphere with absorption, multiple scattering, and complicated physical and geometrical parameters. Notwithstanding these difficulties, it is possible to obtain a useful physical insight into the general form of this law by considering a very simplified model, consisting of a homogeneous atmosphere, in which vertical heights are small in relation to the horizontal distances between town and observatory, and which the scattering is limited to a cone of small angle whose axis lies in the direction of the incident beam. The limited scale height and optical thickness of the real atmosphere, and the forward-scattering characteristics of aerosols lend some plausibility to these simplifications.
 
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  Call Number IDA @ intern @ Serial 2633  
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Author Garstang, R. H. url  openurl
  Title Improved scattering formula for calculations of artificial night-sky illumination Type Journal Article
  Year 1984 Publication The Observatory Abbreviated Journal  
  Volume 104 Issue Pages 196-197  
  Keywords Skyglow  
  Abstract In recent years there has been increased interest in measuring the artificial illumination produced in the night sky cities of various sizes at a range of distances from the observer. Examples of such measurements include the work of Treanor on three Italian cities, that of Walker on the cities of various sized in California, and a study by Berry of light pollution in Southern Ontario. There seem to have been few attempts to provide theoretical interpretations of these measurements other than that contained in the paper by Treanor. He developed a simple empirical formula (his equation (6)) for the zenith brigthness due to a distant city as a function of the distance of the observer from the city. Treanor's formula was used by Berry, with a modification which we mention later.

Treanor based his formula on a very ingenious method of estimating the contribution to the zenith brightness of aerosol scattering between the city, treated as a point source, and an element of the atmosphere in the direction of the observer's zenith. Readers are referred to Treanor's paper for details of his derivation. We give here a simple extension of his work which leads to a scattering formula valid under less restrictive assumptions.
 
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  Notes Approved no  
  Call Number IDA @ intern @ Serial 2638  
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Author Garstang, R. H. url  openurl
  Title Predictions of Future Light Pollution for Ground-Based Observatory Sites Type Journal Article
  Year 1989 Publication Bulletin of the American Astronomical Society Abbreviated Journal  
  Volume 21 Issue Pages 759  
  Keywords Skyglow  
  Abstract In a paper now in press (P.A.S.P. March 1989) we have given details of an improved model for calculating the light pollution caused by one or more cities at an observatory or prospective observatory site. The principal difference in the new model from our earlier one is the inclusion of the effects of the curvature of the Earth, which are significant for the large cities at large distances from mountain observatories.  
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  Notes Approved no  
  Call Number IDA @ intern @ Serial 2545  
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Author Garstang, R.H. url  openurl
  Title Light Pollution at Mount Wilson: The Effects of Population Growth and Air Pollution Type Journal Article
  Year 2000 Publication Memorie della Società Astronomia Italiana Abbreviated Journal  
  Volume 71 Issue 1 Pages  
  Keywords Skyglow  
  Abstract This is the first part of a study of the historical growth of light pollution at Mount Wilson Observatory. The night sky brightness at Mount Wilson due to light pollution from Los Angeles basin was calculated for the years 1910 to 1990, neglecting changes in lighting technology, and without any air pollution ('smog'). The very large effect of population growth is shown. We made a simple extension of our night sky brightness program to include a layer of smog. Two possibilities of constant density and finite thickness. The ground level density is determined by the visibility. We assume a smog layer whose density increases from zero in 1920 to appropriate values for the years from 1950. We added this layer to out model and repeated the Mount Wilson calculations. An average smog layer reduces the visual brightness at the present time by about 6 percent.  
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  Call Number IDA @ intern @ Serial 2544  
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Author Dunster, G.P.; de la Iglesia, L.; Ben-Hamo, M.; Nave, C.; Fleischer, J.G.; Panda, S.; de la Iglesia, H.O. url  doi
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  Title Sleepmore in Seattle: Later school start times are associated with more sleep and better performance in high school students Type Journal Article
  Year 2018 Publication Science Advances Abbreviated Journal Sci. Adv.  
  Volume 4 Issue 12 Pages eaau6200  
  Keywords Human Health  
  Abstract Most teenagers are chronically sleep deprived. One strategy proposed to lengthen adolescent sleep is to delay secondary school start times. This would allow students to wake up later without shifting their bedtime, which is biologically determined by the circadian clock, resulting in a net increase in sleep. So far, there is no objective quantitative data showing that a single intervention such as delaying the school start time significantly increases daily sleep. The Seattle School District delayed the secondary school start time by nearly an hour. We carried out a pre-/post-research study and show that there was an increase in the daily median sleep duration of 34 min, associated with a 4.5% increase in the median grades of the students and an improvement in attendance.  
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  ISSN 2375-2548 ISBN Medium  
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  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2131  
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