



\ifthenelse {\boolean{paper}}
{
\abstract{ This paper proposes a methodology for
creating failure mode models of safety critical systems, which
have a common and integrateable notation
for mechanical, electronic and software domains.
The proposed methodology is bottom-up and 
modular.
}
}
{}

 
\section{Introduction}

\section{Some requirements for a failure mode methodolgy}
\begin{itemize}
\item All component failure modes must be considered in the model.
\item It should be easy to integrate mechanical, electronic and software models.
\item It should be re-usable, in that commonly used modules can be re-used in other designs/projects.
\item It should have a formal babsis, that is to say it should be able to produce mathematical proofs
for its results.
\item It should be capable of producing reliability and danger evaluation statistics.
\item It should be easy to use.
\end{itemize}


OK need to describe the need for it



AND then how we can solve all there problems


AND then a rough outline of what is needed


AND then a general description of symptom extraction

AND the hierarchy...


Probab about 3 pages
