From 38c62a90dc5a8e55aeae7ddab796279e6cf3e0b8 Mon Sep 17 00:00:00 2001 From: Robin Clark Date: Tue, 4 Oct 2011 21:10:09 +0100 Subject: [PATCH] Corrected FMMD - vs FMEA rigourous comparison figures --- presentations/fmea/fmea_pres.tex | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/presentations/fmea/fmea_pres.tex b/presentations/fmea/fmea_pres.tex index 535edaf..dcdafe7 100644 --- a/presentations/fmea/fmea_pres.tex +++ b/presentations/fmea/fmea_pres.tex @@ -823,10 +823,10 @@ analysis scenarios to consider is show in equation~\ref{eqn:anscen}. To see the effects of reducing `state~explosion' we can use an example. % with fixed numbers %for components in a functional group, and failure modes per component. -Let us take a system with 3 levels, +Let us take a system with 4 levels (with a top/system 0 level), with three components per functional group and three failure modes per component, and apply these formulae. -Having three levels (in addition to the top zero'th level) +Having 4 levels (in addition to the top zero'th level) will require 81 base level components. $$ @@ -840,7 +840,7 @@ $$ $$ %\begin{equation} % \label{eqn:anscen} - \sum_{n=0}^{3} {3}^{n}.3.3.(2) = 720 + \sum_{n=0}^{4} {3}^{n}.3.3.(2) = 2178 %\end{equation} $$ \end{frame} @@ -848,7 +848,7 @@ $$ \begin{frame} \frametitle{FMMD - Failure Mode Modular De-Composition} -Thus for FMMD we needed to examine 720 failure mode scenarios, and for traditional FMEA +Thus for FMMD we needed to examine 2178 failure mode scenarios, and for traditional FMEA type analysis methods 19440. % In practical example followed through, no more than 9 components have ever been required for a functional % group and the largest known number of failure modes has been 6.