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<DIV dir=ltr align=left><SPAN class=706350716-15022007><FONT face=Arial
color=#0000ff size=2>Hi Michail and Phani,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=706350716-15022007><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=706350716-15022007><FONT face=Arial
color=#0000ff size=2>That is correct, there are no variance reduction techniques
currently implemented.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=706350716-15022007><FONT face=Arial
color=#0000ff size=2>VR for SPECT were developed and are currently being
implemented in GATE by the Ghent group.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=706350716-15022007><FONT face=Arial
color=#0000ff size=2>VR for PET are under development. <SPAN
class=224501416-15022007>The calculations in the phantom and the scanner are
separated by the Brest group. </SPAN>The strategies will be discussed
at the next OpenGATE meeting.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=706350716-15022007><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=706350716-15022007><FONT face=Arial><FONT
color=#0000ff><FONT size=2><SPAN class=224501416-15022007>Best
Regards</SPAN>,</FONT></FONT></FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=706350716-15022007><FONT face=Arial
color=#0000ff size=2>Assen</FONT></SPAN></DIV></DIV><BR>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>From:</B> gate-users-bounces@lists.healthgrid.org
[mailto:gate-users-bounces@lists.healthgrid.org] <B>On Behalf Of </B>Phani
MANCHIRAJU<BR><B>Sent:</B> Thursday, February 15, 2007 10:53 AM<BR><B>To:</B>
Mikhail Shilov<BR><B>Cc:</B> gate-users@lists.healthgrid.org<BR><B>Subject:</B>
Re: [Gate-users] Variance Reduction in Gate<BR></FONT><BR></DIV>
<DIV></DIV>Hi,<BR><BR>You could use different random number seeds for the
simulations, this should help in variance reduction. From what I know, there is
no other way in which variance reduction could be achieved. No idea about how
importance sampling could be done in Gate.<BR><BR>Phani<BR><BR>
<DIV><SPAN class=gmail_quote>On 2/15/07, <B class=gmail_sendername>Mikhail
Shilov</B> <<A href="mailto:mshilov1@jhmi.edu">mshilov1@jhmi.edu</A>>
wrote:</SPAN>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">Greetings
All,<BR><BR>I just wanted to confirm that there is no variance reduction
techniques<BR>such as importance sampling implemented in Gate as of today. Is
that<BR>right?<BR>Thanks<BR><BR><BR><BR>Mikhail A. Shilov<BR>The Johns Hopkins
University<BR>Department of Radiology<BR>Division of Medical Imaging
Physics<BR>Tel: 443-287-7315<BR>Fax: 410-614-1977<BR>mailto:
<A
href="mailto:mshilov1@jhmi.edu">mshilov1@jhmi.edu</A><BR>_______________________________________________
<BR>Gate-users mailing list<BR><A
href="mailto:Gate-users@lists.healthgrid.org">Gate-users@lists.healthgrid.org</A><BR><A
href="http://lists.healthgrid.org/mailman/listinfo/gate-users">http://lists.healthgrid.org/mailman/listinfo/gate-users
</A><BR></BLOCKQUOTE></DIV><BR>
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