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

JMC proof read

Browse Source
This commit is contained in:
Robin Clark 2012-06-21 20:48:27 +01:00
parent 9a2b15345d
commit e797ce5082
1 changed files with 7 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
submission_thesis/CH4_FMMD/copy.tex
View File

@ -481,6 +481,7 @@ defined by $ G_v = 1 + \frac{R2}{R1} $ at the output.
As the resistors work to provide a specific function, that of a potential divider,
we can treat them as a collection of components with a specific functionality---which can be termed a `{\fg}'.
This {\fg} has two members, $R1$ and $R2$.
%
Using the EN298 specification for resistor failure~\cite{en298}[App.A],
we can assign failure modes of $OPEN$ and $SHORT$ to the resistors individually (assignment of failure modes
is discussed in more detail in section~\ref{sec:resistorfm}).
@ -502,7 +503,7 @@ We represent a resistor and its failure modes as a directed acyclic graph (DAG)
\path (R) edge (RSHORT);
\path (R) edge (ROPEN);
\end{tikzpicture}
\caption{DAG representing a resistor and its failure modes}
\caption{DAG representing a resistor and its failure modes.}
\label{fig:rdag}
\end{figure}
@ -521,7 +522,7 @@ Each {\fc} is analysed to determine the `symptom'
of the potential dividers' operation. For instance
if resistor $R_1$ were to become open, then the potential~divider would not be grounded and the
voltage output from it would float high (+ve).
This would mean the symptom of the failed potential divider would be voltage high output.%We can now consider the {\fg}
This would mean the symptom of the failed potential divider would be voltage high output. %We can now consider the {\fg}
%as a component in its own right, and its symptoms as its failure modes.
{ \small
@ -998,7 +999,7 @@ Failure Scenario & A single failure mode (or a combination), used to
\subsection{Parts, Components and Base Components.}
A component is anything we use to build %a product or
A component is anything we use to build a %a product or
system.
It could be something %quite complicated
like an %integrated
@ -1023,7 +1024,7 @@ and say that we want to define an atomic entity. % used as a building block.
%The term component, in American English, can mean a building block or a part.
%In British-English a component generally is given to mean the definition for part above.
We define {\bc} to be the lowest level---or entities we begin with in our analysis---of component that we use as a building block.
This is a choice made by the analyst, often guided by the standards to which the analysis is being performed to.
This is a choice made by the analyst, often guided by the standards to which the analysis is being performed. % to.
%
Both op-amps and transistors have published statistical failure rates and yet an op-amp is constructed from transistors.
%
@ -1041,7 +1042,7 @@ to which we are approving/analysing a system.
%% FUCKING STEREO SUB_SYSTEM EXAMPLE, THE FUCKING CHILDRENS SECTION
\subsection{definition of terms: sound system example.}
\subsection{Definition of terms: sound system example.}
%000000elpful here to define the terms, `system', `functional~group', `component', `base~component', `symptom' and `derived~component/sub-system'.
%These are listed in table~\ref{tab:symexdef}.
@ -1125,7 +1126,7 @@ the symptoms of failure of the {\fg} are the failure modes of this new `{\dc}'.
Electrical components have data-sheets associated with them. The data sheets
supply detailed information on the component as supplied by the manufacturer.
%
Because they are design related they rarely rarely show %clearly detail the
Because they are design related they rarely show %clearly detail the
failure modes of the component, with environmental factors and MTTF~\cite{sccs}[p.165] statistics.
Given the growing usage of FMEA/FMEDA in industry this may change.
Currently, failure mode information is generally only available for generic component types~\cite{mil1991, fmd91}.