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<DIV><FONT face=Arial size=2><SPAN class=031255516-12092008>Hi
All,</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=031255516-12092008></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=031255516-12092008>I'm trying to model
manually-operated windows, ie that can only be opened or closed when
someone is around to do it. Thus, I need a way to modify a variable only at
certain times - for example, so I can change my airchange rate
accroding to outdoor temp **only if** hr>8 and hr<21. I know of type
93 (input value recall), but can't think of how this helps. I also know about
chaining GT(), LT(), etc, to form logical operations, but everything I can think
of would assign a new value at each timestep. I need more of a real
if(condition)-then(action), but I know these don't exist in trnsys. Any
thoughts?</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=031255516-12092008></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN
class=031255516-12092008>Thanks,</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=031255516-12092008>Cramer</SPAN></FONT></DIV>
<DIV> </DIV>
<DIV align=left>
<P style="MARGIN: 0cm 0cm 0pt" align=left><B><FONT face=Arial size=1><SPAN
style="FONT-WEIGHT: bold; FONT-SIZE: 8pt; FONT-FAMILY: Arial">J. Cramer
Silkworth</SPAN></FONT></B><?xml:namespace prefix = o ns =
"urn:schemas-microsoft-com:office:office" /><o:p></o:p></P>
<P style="MARGIN: 0cm 0cm 0pt"><B><FONT face=Arial size=1><SPAN
style="FONT-WEIGHT: bold; FONT-SIZE: 8pt; FONT-FAMILY: Arial">Transsolar Climate
Engineering</SPAN></FONT></B><B><FONT size=1><SPAN
style="FONT-WEIGHT: bold; FONT-SIZE: 8pt"><o:p></o:p></SPAN></FONT></B></P>
<P style="MARGIN: 0cm 0cm 0pt"><FONT face=Arial size=1><SPAN
style="FONT-SIZE: 8pt; FONT-FAMILY: Arial">Technical consulting for energy
efficiency and environmental quality in buildings.</SPAN></FONT><FONT
size=1><SPAN style="FONT-SIZE: 8pt"><o:p></o:p></SPAN></FONT></P>
<P style="MARGIN: 0cm 0cm 0pt"><FONT face=Arial size=1><SPAN
style="FONT-SIZE: 8pt; FONT-FAMILY: Arial">145 Hudson
Street</SPAN></FONT><o:p></o:p></P>
<P style="MARGIN: 0cm 0cm 0pt"><FONT face=Arial size=1><SPAN
style="FONT-SIZE: 8pt; FONT-FAMILY: Arial">Suite 402</SPAN></FONT><FONT
size=1><SPAN style="FONT-SIZE: 8pt"><o:p></o:p></SPAN></FONT></P>
<P style="MARGIN: 0cm 0cm 0pt"><FONT face=Arial size=1><SPAN
style="FONT-SIZE: 8pt; FONT-FAMILY: Arial">New York, NY 10013</SPAN></FONT><FONT
size=1><SPAN style="FONT-SIZE: 8pt"><o:p></o:p></SPAN></FONT></P>
<P style="MARGIN: 0cm 0cm 0pt"><FONT face=Arial size=1><SPAN
style="FONT-SIZE: 8pt; FONT-FAMILY: Arial">Office: 212-219-2255</SPAN></FONT><o:p></o:p></P>
<P style="MARGIN: 0cm 0cm 0pt"><FONT face=Arial size=1><SPAN
style="FONT-SIZE: 8pt; FONT-FAMILY: Arial">Mobile: 347-283-2547</SPAN></FONT><FONT
size=1><SPAN style="FONT-SIZE: 8pt"><o:p></o:p></SPAN></FONT></P>
<P style="MARGIN: 0cm 0cm 0pt"><FONT face=Arial size=1><SPAN
style="FONT-SIZE: 8pt; FONT-FAMILY: Arial"><A
title=mailto:silkworth@transsolar.com
href="mailto:silkworth@transsolar.com">silkworth@transsolar.com</A></SPAN></FONT></P></DIV>
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