From d7dee62f42546febff4d223a9cceaac269841c6e Mon Sep 17 00:00:00 2001 From: "Robin P. Clark" Date: Wed, 11 Sep 2013 16:33:22 +0100 Subject: [PATCH] we removal now have 1,2,3 8 --- submission_thesis/CH8_Conclusion/copy.tex | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/submission_thesis/CH8_Conclusion/copy.tex b/submission_thesis/CH8_Conclusion/copy.tex index ee046d0..4cb4524 100644 --- a/submission_thesis/CH8_Conclusion/copy.tex +++ b/submission_thesis/CH8_Conclusion/copy.tex @@ -258,8 +258,8 @@ resistor{\lambda}_p = {\lambda}_{b}{\pi}_Q{\pi}_E Thus thermistor, bead type, `non~military~spec' is given a FIT of 315.0. % \frategloss -Using the RIAC finding the following table (table \ref{tab:stat_single}) can be created, -showing the FIT values for all single failure modes. +Using the RIAC finding the following (table~\ref{tab:stat_single}) can be created which +presents the FIT values for all single failure modes. %\glossary{name={FIT}, description={Failure in Time (FIT). The number of times a particular failure is expected to occur in a $10^{9}$ hour time period.}} \fmmdglossFIT % @@ -331,7 +331,7 @@ failure rate statistics to double failures can also be determined. %% % Considering the failure modes to be statistically independent -the FIT values for all the combinations +the FIT values for all the combinations of failures in the electronic examples from chapter~\ref{sec:chap5} in table~\ref{tab:ptfmea2} can be calculated. % The failure mode of most concern, the undetectable {\textbf{FLOATING}} condition, @@ -339,8 +339,9 @@ requires that resistors $R_1$ and $R_2$ both fail. % Multiplying the MTTF probabilities for these types of resistor failing gives the MTTF for both failing. % -The FIT value of 12.42 corresponds to -$12.42 \times {10}^{-9}$ failures per hour. Squaring this gives $ 154.3 \times {10}^{-18} $. +The FIT value of 12.42 corresponds to $12.42 \times {10}^{-9}$ failures per hour. +% +Squaring this gives $ 154.3 \times {10}^{-18} $. % This is an astronomically small MTTF, and so small that it would probably fall below a threshold to sensibly consider. @@ -359,7 +360,8 @@ In a large FMMD model, system/top level failures can be traced down to {\bc} {\fms}. % To determine the MTTF probability -for a system level failure, the MTTF statistics are added for all its possible causes. +for a system level failure, +the MTTF statistics are added for all its possible causes. % Thus even for large FMMD models accurate statistics for electronic sourced failures can be calculated.