From 6cf0515b17184c860c013e450662f9d34352797c Mon Sep 17 00:00:00 2001 From: Robin Clark Date: Mon, 9 May 2011 19:37:04 +0100 Subject: [PATCH] proof read, wish had done this b4 senifn to sups --- noninvopamp/noninvopamp.tex | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/noninvopamp/noninvopamp.tex b/noninvopamp/noninvopamp.tex index 263d165..d54554a 100644 --- a/noninvopamp/noninvopamp.tex +++ b/noninvopamp/noninvopamp.tex @@ -260,7 +260,7 @@ regions) see figure~\ref{fig:fgampa}. Let us consider, for the sake of example, that the voltage follower (very low gain of 1.0) amplification chracteristics from -TC1 and TC6 can be considered as low output from the OPAMP for the application +TC2 and TC6 can be considered as low output from the OPAMP for the application in hand (say milli-volt signal amplification). For this amplifier configuration we have three failure modes, $AMPHigh, AMPLow, LowPass$.%see figure~\ref{fig:fgampb}. @@ -279,9 +279,9 @@ We can now derive a `component' to represent this amplifier configuration (see f %failure mode contours). -\clearpage +%\clearpage -\section{Directed Acyclic Failure Mode Graph} +\section{Failure Mode as a Directed Acyclic Graph} We can now represent the FMMD analysis as a directed graph, see figure \ref{fig:noninvdag0}. With the information structured in this way, we can trace the high level failure mode symptoms @@ -411,11 +411,11 @@ back to their potential causes. -\clearpage +%\clearpage \section{Extracting Fault Trees from the DAG} -We can derive an FTA diagram for a top level event, by tracing back through the DAG. +We can derive an FTA~\cite{nucfta}~\cite{nasafta} diagram for a top level event, by tracing back through the DAG. Where we come to a node with more than one error source, this becomes an or gate in the FTA diagram. Tracing back from the top level event $AMP Low$ we are lead to the $OPAMP latch down$ and $OP amp Noop$. These two events can cause the symptom $AMP Low$. @@ -499,8 +499,8 @@ The FTA diagram directly derived from the FMMD DAG is shown in figure \ref{fig:n %% To render them correctly replace '-20' with 'right' and add the 'absolute' %% option to the tikzpicture environment. The absolute option makes the %% node labels ignore the rotation of the parent node. - \node [or] at (g1.south) [label=-20:G01] {}; - \node [or] at (g2.south) [label=-20:G02] {}; + %\node [or] at (g1.south) [label=-20:G01] {}; + \node [or] at (g2.south) [label=-20:G01] {}; \node [or] at (g4.south) [label=-20:G02] {}; % \node [and] at (g3.south) [label=-20:G03] {}; % \node [or] at (g4.south) [label=-20:G04] {}; @@ -515,15 +515,15 @@ The FTA diagram directly derived from the FMMD DAG is shown in figure \ref{fig:n \end{tikzpicture} \label{fig:noninvfta} -\caption{Example FTA for a Gas Supply with two Shutoff Valves} +\caption{Example FTA Derived from the DAG for symptom `Amp Low'} \end{figure} -\clearpage +%\clearpage -\clearpage +%\clearpage show an example fault tree, showing the causes and logical (only OR's here) @@ -549,4 +549,5 @@ statistical literature is available ~\cite{mil1991}~\cite{fmd91}. Software used to edit these diagrams, keeps the model in a directed acyclic graph data structure for this purpose. +\clearpage %\end{document} \ No newline at end of file