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great a short abstract was required. NO ONE TOLD ME

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submission_thesis/colophon/copy.tex
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@ -118,7 +118,7 @@ Typeset in \LaTeX \today.
\renewcommand{\baselinestretch}{1.5}
\clearpage
\chapter*{Declaration}
@ -136,3 +136,128 @@ Signed
\\
Dated
\clearpage
\section*{Abstract}
\subsection*{Failure Mode Modular De-Composition}
%
% This should be a three hundred word summary of the work and findings
% Supervisors did not warn me this was required.
% I found out by reading the OU ``how to get a PhD'' book in the bath, and then wading through the Brighton University
% regulations where it is stated on page 14 of a 30+ page document filled with mostly n/a regulations to me.
% Ho HUM. No wonder these shits have trouble working in the real world.
%
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% BEGINING --- Introduce the field
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
The certification process of safety critical products for European and other international
standards typically demand environmental stress, endurance and electro magnetic compatibility testing.
%
Theoretical, or `static~testing' also a requirement.
%
Failure Mode effects Analysis (FMEA) is a tool used for static testing.
FMEA is a bottom-up technique that aims to assess the effects
of all component failure modes in a system.
%
Its use is traditionally limited to hardware systems. % only.
%
With the growing complexity of modern electronics traditional FMEA
is suffering from state explosion and re-use of analysis problems.
%
Also with the now ubiquitous use of micro-controllers in smart~instruments and control systems,
software is increasingly being seen as a `missing~factor' for FMEA. % analysis.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Middle work and findings
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
This thesis presents a new modular variant of FMEA, Failure Mode Modular Decomposition (FMMD).
%
FMMD has been designed to integrate mechanical/electronic and software
failure models, by treating them all as components in terms of their failure modes.
%
For instance, software functions,
electronic and mechanical components
can all be assigned sets of failure modes.
%
FMMD builds failure mode models from the bottom-up by incrementally analysing
{\fgs} of components, using the results of analysis to create higher level {\dcs},
which in turn can be used to build {\fgs}.
%
In this way a hierarchical failure mode model
is built.
%
Software functions are treated as components by FMMD and can thus be incorporated seamlessly into
the failure mode hierarchical model.
%
A selection of examples, electronic circuits and hardware/software hybrids are analysed using
this new methodology.
%
The results of these analyses are then discussed from the perspective of safety critical application.
%
Performance in terms of test efficiency is greatly improved by FMMD and
the examples analysed and theoretical models are used to demonstrate this.
%
%Because FMMD is modular and hierarchical, and deals with all its objects in
%terms of their failure mode behaviour, it is ideally suited to creating integrated software and hardware models.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% End what has been achieved ---- all in 300ish word OK here we go.
%Conclusions are presented listing the
%and FMMD is compared with traditional HFMEA and SFMEA.
This thesis presents a methodology that solves the state explosion problems of FMEA;
provides integrated hardware and software failure mode models;
facilitates multiple failure mode analysis;
encourages re-use of analysis work
and can be used to produce traditional format FMEA reports.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% The certification process of safety critical products for European and other international
% standards often demand environmental stress, endurance and Electro Magnetic Compatibility (EMC) testing.
% Theoretical, or `static testing',is often also required. Failure Mode effects Analysis (FMEA) is a tool used for static testing.
% Its use is traditionally applied to hardware (electrical and mechanical) systems.
% With the increasing use of micro-controllers in smart~instruments and control systems,
% software is increasingly being seen as the `missing factor' in FMEA analysis.
% This paper presents a new modular variant of FMEA, Failure Mode Modular Decomposition (FMMD).
% Because FMMD is modular and hierarchical, and deals with all its objects in
% % terms of their failure mode behaviour, it is ideally suited to creating integrated software and hardware models.
% FMEA is a bottom-up technique that aims to assess the effects
% of all component failure modes on a system. It is used both as a design tool (to determine weaknesses),
% and is a requirement of certification of safety critical products. FMEA has been successfully applied to
% mechanical, electrical and hybrid electro-mechanical systems. Work on software FMEA (SFMEA) is beginning,
% but at present no technique for SFMEA that integrates hardware and software models exists.
% Software in current embedded systems practise sits on top of most modern safety critical control systems
% [and inside many data collection/actuator modules (smart~instruments)], and defines their most important
% system wide behaviour, interfaces and communications. Currently standards that demand FMEA for hardware
% (e.g. EN298, EN61508), do not specify it for software, but instead specify, computer architecture, good software practise,
% review processes and language feature constraints. Where FMEA traces component failure modes to resultant system failures,
% software has been left in a non-analytical limbo of best practises and constraints. Where SFMEA has been applied---for some
% automotive and highly safety critical systems---it has always been performed separately from hardware FMEA (HFMEA).
% %
% At present the hardware/software interface is a source for confusion and misunderstanding, and in many organisations,
% the actual design teams for software and hardware work in separate departments. Subtle errors of electronic systems for instance,
% may not be picked up by software specialists, and vice versa. It would be desirable to have a methodology that provides seamless
% software and hardware integration in its failure modelling. FMMD has been designed to integrate mechanical/electronic and software
% failure models, by treating all modular components in terms of their failure modes. For instance, a software function,
% or an electronic or a mechanical component can be assigned a known set of failure modes.
% This paper presents an overview of the FMMD methodology and then an FMMD analysis of a simple software/hardware hybrid sub-system.
%
%
% The example system chosen is a 4->20mA input circuit consisting of a resistive element, multiplexer (MUX),
% Analogue to Digital Converter (ADC) and two software functions. The purpose of this system is to convert an
% electrical current signal into a value for use in software. FMMD is applied to the hardware (resistive element, MUX and ADC)
% and to the software components (two `C' functions), producing one integrated failure mode model.
% The 4->20mA input circuitry used in the example and its related software, are accepted practise and in
% common use, and therefore its failure mode behaviour is well known and understood. For this reason it is a
% good example to use for comparing the results from FMMD analysis with known failure mode behaviour
% from the field/direct experience of engineers. The failure model is then discussed and compared with
% heuristic knowledge of 4->20mA inputs, circuitry and software.
% Conclusions are then presented listing the benefits and draw-backs of analysing the
% hardware/software hybrid system using FMMD, and FMMD is compared with traditional HFMEA and SFMEA.