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<DIV>Yeonsook,</DIV>
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<DIV>Since we use the Perez algorithm to split Global Horizontal into Direct and
Diffuse in our global weather data platform as part of the input stream to
support building and energy modeling, we would love to see your results when
they are available. </DIV>
<DIV>Part of the data we used to calibrate the Global and Direct came from the
University of Oregon’s network of radiation sensors in the Northwest. I do
not know what they have in Diffuse but we found their multiple, co-located
sensors to be very useful in our studies of Global and Direct radiation.</DIV>
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<DIV>- Chuck</DIV>
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style="FONT-FAMILY: 'Calibri'; COLOR: #000000; FONT-SIZE: 12pt">_________________<BR>Chuck
Khuen<BR>Principal<BR>Weather Analytics Inc.<BR>781-856-5383</DIV>
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<DIV style="font-color: black"><B>From:</B> <A title=yeonsook.heo@gmail.com
href="mailto:yeonsook.heo@gmail.com">Yeonsook Heo</A> </DIV>
<DIV><B>Sent:</B> Friday, August 19, 2011 12:57 PM</DIV>
<DIV><B>To:</B> <A title=bldg-sim@lists.onebuilding.org
href="mailto:bldg-sim@lists.onebuilding.org">bldg-sim@lists.onebuilding.org</A>
</DIV>
<DIV><B>Subject:</B> [Bldg-sim] Reliable dataset of diffuse irradiance measured
on horizontal and vertical surfaces</DIV></DIV></DIV>
<DIV> </DIV></DIV>
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style="FONT-STYLE: normal; DISPLAY: inline; FONT-FAMILY: 'Calibri'; COLOR: #000000; FONT-SIZE: small; FONT-WEIGHT: normal; TEXT-DECORATION: none">Hi
all,<BR><BR><BR>We are working on quantifying uncertainty in diffuse irradiance
calculated by the Perez model. <BR>We quantify uncertainty by comparing Perez
model outcomes against measured diffuse irradiance on tilted surfaces through a
mathematical formulation that can identify where the Perez model falls short for
its predictability. <BR><BR>For this analysis, we need the two measured data
from the same period on the same location: <BR>(1) measured diffuse irradiance
on tilted surfaces <BR>(2) measured diffuse irradiance on horizontal surfaces
(used as input for the Perez model)<BR><BR>We have hard time obtaining enough
data for analysis. <BR><BR>Can anyone know where we can access reliable dataset
including the two measured data?<BR><BR><BR><BR>Thanks,<BR>Yeonsook<BR
clear=all><BR><BR>-- <BR><BR>Ph.D student<BR>High Performance
Buildings<BR>College of Architecture<BR>Georgia Institute of Technology<BR><BR>
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