From 3bc024e5457f6f96aabc76fad3a9a7f97ea8c31f Mon Sep 17 00:00:00 2001 From: Robin Clark Date: Sun, 13 May 2012 17:42:11 +0100 Subject: [PATCH] final fiddling around. This is as was sent for the second CH4 review. This time Andrew might look at it. --- mybib.bib | 2 +- submission_thesis/CH4_FMMD/copy.tex | 34 ++++++++++++------------- submission_thesis/CH5_Examples/copy.tex | 1 + submission_thesis/Makefile | 1 + 4 files changed, 20 insertions(+), 18 deletions(-) diff --git a/mybib.bib b/mybib.bib index d9ed807..b1e5c9b 100644 --- a/mybib.bib +++ b/mybib.bib @@ -2,7 +2,7 @@ @BOOK{dmfnt, AUTHOR = "R Garnier, J Taylor", - TITLE = "Discrte Mathematics for New Technology ISBN 0-7503-0135-X", + TITLE = "Discrete Mathematics for New Technology ISBN 0-7503-0135-X", PUBLISHER = "IoP", YEAR = "1992" } diff --git a/submission_thesis/CH4_FMMD/copy.tex b/submission_thesis/CH4_FMMD/copy.tex index 6ee7e2e..1d9ff49 100644 --- a/submission_thesis/CH4_FMMD/copy.tex +++ b/submission_thesis/CH4_FMMD/copy.tex @@ -51,23 +51,19 @@ to build higher level groups. \section{Introduction} -This -\ifthenelse {\boolean{paper}} -{ -paper -} -{ -chapter -} -starts with a worked example using the new methodology, Failure Mode Modular De-composition (FMMD). +This chapter +starts with an overview of current failure modelling techniques, and then worked example using the new methodology, +Failure Mode Modular De-composition (FMMD). This is followed by a discussion on the design of the FMMD methodology and then an ontological description is given using UML class models. A notation is then described to index and classify objects created in FMMD hierarchical models. +\subsection{Overview of current failure mode modelling techniques} + We briefly analyse four current methodologies. Comprehensive overviews of these methodologies may be found -in ~\cite{safeware,sccs}. +in ~\cite{safeware,sccs,nasafta,nucfta,bfmea}. \paragraph{Fault Tree Analysis (FTA).} FTA~\cite{nasafta,nucfta} is a top down methodology in which a hierarchical diagram is drawn for @@ -1030,7 +1026,7 @@ The symptoms of failure of the {\fg} are the failure modes of this new `derived %1991 reliability manual\cite{mil1991} applies a FIT of 100 for this generic type of component} Electrical components have detailed data-sheets associated with them. A useful extension of this could -be failure modes of the component, with environmental factors and MTTF statistics. +be failure modes of the component, with environmental factors and MTTF~\cite{sccs}[p.165] statistics. Currently this sort of failure mode information is generally only available for generic component types \cite{mil1991}. \begin{table}[h] @@ -1573,8 +1569,8 @@ failure modes being the failure symptoms of the {\fg} from which it was derived. %where its failure modes, are the symptoms from {\fg}. % Note that the {\dc} must have a higher abstraction level than the {\fg} -from which it was derived---or---in other words, the symptom abstraction process `$\derivedc$' increments -the abstraction level $abslev$, as stated in equation~\ref{eqn:abslevinc}. +from which it was derived---or---in other words, the symptom abstraction process `$\derivec$' increments +the abstraction level $\abslev$, as stated in equation~\ref{eqn:abslevinc}. The symptom abstraction process is described formally and algorithmically in sections~\ref{sec:formalfmmd} and \ref{sec:algorithmfmmd} respectively. @@ -1845,9 +1841,13 @@ component level failure modes. This allows cut sets~\cite{nasafta}[Ch.1p3] to be determined by traversing the DAG from top level events down to their causes. % -This has the added advantage of each {\fg} to {\dc} stage being a documented -failure mode reasoning entity. Compare this to traditional FMEA where -we only have one stage, base component failure mode to top level event. +An added advantage of FMMD, is that there are typically several stages of reasoning +to go from a base component failure mode to a system/top level event. +% +Each of these reasoning stages are represented by {\fg} to {\dc} analysis processes, traversing up the FMMD hierarchy. +% +Compare this to traditional FMEA where +we only have one reasoning stage, that of base component failure mode to top level event. % \item{ It should be capable of producing reliability and danger evaluation statistics.} % The minimal cuts sets for the system level failures can have computed MTTF @@ -1889,7 +1889,7 @@ An example demonstrating multiple failure mode analysis may be found in section~ { %\tiny \begin{table}[ht] \caption{Features of static Failure Mode analysis methodologies} % title of Table -%\centering % used for centering table +\centering % used for centering table \begin{tabular}{||l|c|c|c|c|c||} \hline \hline % \textbf{Des.} & \textbf{FTA} & \textbf{FMEA} & \textbf{FMECA} & \textbf{FDEMA} & \textbf{FMMD} \\ diff --git a/submission_thesis/CH5_Examples/copy.tex b/submission_thesis/CH5_Examples/copy.tex index 245cbf1..3a06cdc 100644 --- a/submission_thesis/CH5_Examples/copy.tex +++ b/submission_thesis/CH5_Examples/copy.tex @@ -63,6 +63,7 @@ As all forms of FMEA are bottom-up processes, we start with the lowest or most b \subsection{Determining the failure modes of components} \label{sec:determine_fms} In order to apply any form of Failure Mode Effects Analysis (FMEA) we need to know the ways in which the components we are using can fail. +A good introduction to hardware and software failure modes may be found in~\cite{sccs}[pp.114-124]. Typically when choosing components for a design, we look at manufacturers' data sheets, which describe the environmental ranges and tolerances, and can indicate how a component may fail/behave under certain conditions or environments. diff --git a/submission_thesis/Makefile b/submission_thesis/Makefile index 50ef246..40388aa 100644 --- a/submission_thesis/Makefile +++ b/submission_thesis/Makefile @@ -12,6 +12,7 @@ clean: rm ${CHAPTERS} bib: + pdflatex thesis # do this first otherwise bibtex gets its knickers in a twist bibtex thesis chapters_sub_make: