better refs, 2 weeks in no C2H5O.

This commit is contained in:
Robin Clark 2011-02-26 18:38:32 +00:00
parent ff8493147d
commit 5f34b2c6e1
3 changed files with 16 additions and 9 deletions

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@ -2,6 +2,12 @@
% my bib file.
@ARTICLE{fmd91,
AUTHOR = "Reliability Analysis Center",
TITLE = "Failure Mode/Mechanisms Distributions 1991",
JOURNAL = "United States Department of Commerce",
YEAR = "1991"
}
% $Id: mybib.bib,v 1.3 2009/11/28 20:05:52 robin Exp $
@article{Clark200519,

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@ -156,7 +156,7 @@ for the effects of component failures.
All components have a set of known `failure modes'.
In other words we know that a given component can fail in several distinct ways.
Studies have been published which list common component types
and their sets of failure modes, often with MTTF statistics \cite{mil1991}.
and their sets of failure modes~\cite{fmd91}, often with MTTF statistics~\cite{mil1991}.
Thus for each component, an analysis is made for each of its failure modes,
with respect to its effect on the
circuit. Each one of these scenarios is termed a `test case'.
@ -170,9 +170,10 @@ Where this occurs a circuit re-design is probably the only sensible course of ac
\subsection{Single Fault FMEA Analysis \\ of PT100 Four wire circuit}
\label{fmea}
This circuit simply consists of three resistors.
Resistors according to the DOD Electronic component fault handbook
1991, fail by either going OPEN or SHORT circuit \cite{mil1991}.
The PT100 circuit consists of three resistors, two `current~supply'
wires and two `sensor' wires.
Resistors according to the European Standard EN298:2003~\cite{en298}[App.A]
, are considered to fail by either going OPEN or SHORT circuit.
%Should wires become disconnected these will have the same effect as
%given resistors going open.
For the purpose of this analyis;

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@ -104,10 +104,10 @@ failsafes meant that the objective was to iron out common failures
not to rigorously detect all possible failures.
Consequently it was not designed to guarantee to covering all component failure modes,
and has no rigorous in-built safeguards to ensure coverage of all possible
system level outcomes.
system level outcomes~\cite{nasafta}[Section 1.2].
FTA, like all top~down methodologies introduces the very serious problem
of missing component failure modes \cite{faa}[Ch.9].
of missing component failure modes~\cite{faa}[Ch.9].
\paragraph{Outline of FTA Methodology}
FTA works by taking an undesireable event
@ -277,7 +277,7 @@ FMEA described in this section (\ref{pfmea}) is sometimes called `production FME
\subsection{FMECA}
Failure mode, effects, and criticality analysis (FMECA)~\cite{FMD-91} extends FMEA
Failure mode, effects, and criticality analysis (FMECA)~\cite{fmd91} extends FMEA
by associaing failure probabilities with component failure modes.
Essentially this adds a failure outcome criticallity factor to FMEA.
This is a bottom up methodology, which builds on an existing FMEA
@ -326,7 +326,7 @@ this can be the number of operating cycles or demands expected.
\paragraph{Severity `s' value}
Component failure modes can cause failures that have levels of severity or seriousness.
Typical classifications are as follows:~\cite{FMD-91}
Typical classifications are as follows:~\cite{fmd91}
\begin{itemize}
\item Category I - Catastrophic
\item Category II - Critical
@ -364,7 +364,7 @@ $s$ thus:
%%-WIKI- FMECA tends to be preferred over FMEA in space and North Atlantic Treaty Organization (NATO) military applications,
%%-WIKI- while various forms of FMEA predominate in other industries.
A second result, representing the overall reliability and safety of a component or item\cite{FMD-91}[2-17] $C$,
A second result, representing the overall reliability and safety of a component or item~\cite{fmd91}[2-17] $C$,
termed a criticallity number $C_r$ for the component.
We can consider $C$ to be a flat set of component failure modes, using $cfm$ as a variable to represent them.
% where $f \in F$)