robin/Robin_PHD
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

nr compiles as thesis now

Browse Source
This commit is contained in:
Robin Clark 2011-02-14 09:32:34 +00:00
parent 952bbf04ca
commit 99c751c966
2 changed files with 19 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
nr/nr.tex
View File

@ -75,6 +75,8 @@ Assume resistors not from same batch.
Show how parameter change is cancelled out, use sum of squares statistics
to show by how much.
\ifthenelse {\boolean{paper}}
{
\begin{figure}
\begin{tikzpicture}[line width=1pt]
\draw (0,0) -- ++(0,1cm);
@ -118,3 +120,7 @@ to show by how much.
\end{tikzpicture}
\caption{A `network resistor'}
\end{figure}
}
{
electComp not in main thesis director yet
}

21
survey/survey.tex
View File

@ -266,6 +266,8 @@ of corrective action.
\item Possibility to miss the effects of failure modes at SYSTEM level.
\item Possibility to miss environmental effects.
\item No possibility to model base component level double failure modes.
\item Does not model component failure modes
that may cause more than one type of SYSTEM failure.
\end{itemize}
\paragraph{Note.} FMEA is sometimes used in its literal sense, that is to say
@ -383,6 +385,8 @@ The $C_r$ value, for a given serverity $s$ is calculated thus
under which the equipment is operating.
\item Possibility to miss environmental affects.
\item No possibility to model base component level double failure modes.
\item As with all failure mode methodologies based on FMEA, does not model component failure modes
that may cause more than one type of SYSTEM failure.
\end{itemize}
@ -495,10 +499,11 @@ $\lambda_{SD}$, $\lambda_{SU}$, $\lambda_{DD}$, $\lambda_{DU}$).
These new failures are added to the model.
%SD, SU, DD, DU.
\glossary{name={SD},description={Safe Detected; a SYSTEM level failure mode that is considered safe, and is detected by self checking mechanisms}}
\glossary{name={SU},description={Safe Undetected; a SYSTEM level failure mode that is considered safe, and is not detected by self checking mechanisms}}
\glossary{name={DD},description={Dangerous Detected; a SYSTEM level failure mode that is considered dangerous, and is detected by self checking mechanisms}}
\glossary{name={DU},description={Dangerous Undetected; a SYSTEM level failure mode that is considered dangerous, and is not detected by self checking mechanisms}}
\glossary{name={SU},description={Safe Undetected; a SYSTEM level failure mode that is considered safe, and is not detected by self checking mechanisms. See FMEDA~\cite{en61508}}}
\glossary{name={SD},description={Safe Detected; a SYSTEM level failure mode that is considered safe, and is detected by self checking mechanisms. See FMEDA~\cite{en61508}}}
\glossary{name={DD},description={Dangerous Detected; a SYSTEM level failure mode that is considered dangerous, and is detected by self checking mechanisms. See FMEDA~\cite{en61508}}}
\glossary{name={DU},description={Dangerous Undetected; a SYSTEM level failure mode that is considered dangerous, and is not detected by self checking mechanisms. See FMEDA~\cite{en61508}}}
With these classifications, and statistics for each component
we can now calculate statistics for the diagnostic coverage (how good at `self checking' the system is)
@ -590,14 +595,12 @@ With one component failure mode per row,
all the statistical factors for SIL rating can be produced\footnote{A SIL rating will apply
to an installed plant, i.e. a complete installed and working SYSTEM. SIL ratings for individual components or
sub-systems are meaningless, and the nearest equivalent would be the FIT/PFD and SFF and diagnostic coverage figures.}.
\glossary{name={FIT}, description={Failure in Time (FIT). The number of times a particular failure is expected to occur in a $10^{9}$ hour time period.}}
\subsubsection{FMEDA and failure outcome prediction accuracy.}
FMEDA suffers from the same problems of
lack of component failure mode outcome prediction accuracy, as FMEA in section \ref{pfmea}.
@ -651,6 +654,8 @@ and its international analog standard IOC5108.
\item Statistical nature allows a proportion of undetected failures for given S.I.L. level.
\item Allows a small proportion of `undetectable' error conditions.
\item No possibility to model base component level double failure modes.
\item As with all failure mode methodologies based on FMEA, does not model component failure modes
that may cause more than one type of SYSTEM failure.
\end{itemize}
%AND then how we can solve all there problems