diff --git a/standards/paper.aux b/standards/paper.aux index cf635bc..1e55ec5 100644 --- a/standards/paper.aux +++ b/standards/paper.aux @@ -2,10 +2,19 @@ \bibstyle{plain} \bibdata{vmgbibliography,mybib} \@writefile{toc}{\contentsline {section}{\numberline {1}Introduction}{1}} -\@writefile{toc}{\contentsline {section}{\numberline {2}European Safety Standards Legal Framework}{1}} -\@writefile{toc}{\contentsline {section}{\numberline {3}North American Legal Framework}{1}} +\@writefile{toc}{\contentsline {subsection}{\numberline {1.1}Product Life Cycle}{1}} +\@writefile{toc}{\contentsline {section}{\numberline {2}European or `EN' Standards}{1}} +\@writefile{toc}{\contentsline {subsection}{\numberline {2.1}Scope}{1}} +\@writefile{toc}{\contentsline {subsection}{\numberline {2.2}Approval Process}{1}} +\@writefile{toc}{\contentsline {subsection}{\numberline {2.3}Legal Framework}{1}} +\@writefile{toc}{\contentsline {subsection}{\numberline {2.4}References}{1}} +\@writefile{toc}{\contentsline {section}{\numberline {3}North American Standards}{1}} +\@writefile{toc}{\contentsline {subsection}{\numberline {3.1}Scope}{1}} +\@writefile{toc}{\contentsline {subsection}{\numberline {3.2}Approval Process}{1}} +\@writefile{toc}{\contentsline {subsection}{\numberline {3.3}Legal Framework}{1}} +\@writefile{toc}{\contentsline {subsection}{\numberline {3.4}References}{1}} \@writefile{toc}{\contentsline {section}{\numberline {4}Cross Referencing}{1}} -\@writefile{toc}{\contentsline {section}{\numberline {5}EN298}{1}} -\@writefile{toc}{\contentsline {section}{\numberline {6}UL1998}{1}} -\@writefile{toc}{\contentsline {section}{\numberline {7}EN230}{1}} -\@writefile{toc}{\contentsline {section}{\numberline {8}EN61508}{1}} +\@writefile{toc}{\contentsline {section}{\numberline {5}Standard in detail: EN298}{2}} +\@writefile{toc}{\contentsline {section}{\numberline {6}Standard in detail: UL1998}{2}} +\@writefile{toc}{\contentsline {section}{\numberline {7}Standard in detail: EN230}{2}} +\@writefile{toc}{\contentsline {section}{\numberline {8}Standard in detail: EN61508}{2}} diff --git a/standards/paper.log b/standards/paper.log index 2331d84..e4e599c 100644 --- a/standards/paper.log +++ b/standards/paper.log @@ -1,4 +1,4 @@ -This is pdfTeXk, Version 3.141592-1.40.3 (Web2C 7.5.6) (format=pdflatex 2010.2.1) 4 APR 2010 13:40 +This is pdfTeXk, Version 3.141592-1.40.3 (Web2C 7.5.6) (format=pdflatex 2010.5.22) 11 JUN 2010 23:04 entering extended mode %&-line parsing enabled. **paper.tex @@ -360,45 +360,45 @@ LaTeX Font Info: Overwriting symbol font `AMSb' in version `normal' (Font) U/msb/m/n --> U/msb/m/n on input line 34. 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The resistance -of this is directly related to temperature, and may be determined by -look-up tables or a suitable polynomial expression. - - -\begin{figure}[h] - \centering - \includegraphics[width=150pt,bb=0 0 273 483,keepaspectratio=true]{./pt100/vrange.jpg} - % pt100.jpg: 714x180 pixel, 72dpi, 25.19x6.35 cm, bb=0 0 714 180 - \caption{PT100 expected voltage ranges} - \label{fig:pt100vrange} -\end{figure} - - -The voltage ranges we expect from this three stage potential divider -are shown in figure \ref{fig:pt100vrange}. Note that there is -an expected range for each reading, for a given temperature span. -Note that the low reading goes down as temperature increases, and the higher reading goes up. -For this reason the low reading will be reffered to as {\em sense-} -and the higher as {\em sense+}. - -\subsection{Accuracy despite variable \\ resistance in cables} - -For electronic and accuracy reasons a four wire circuit is preffered -because of resistance in the cables. Resistance from the supply - causes a slight voltage -drop in the supply to the PT100. As no significant current -is carried by the two `sense' lines the resistance back to the ADC -causes only a negligible voltage drop, and thus the four wire -configuration is more accurate. - -\subsection{Calculating Temperature from \\ the sense line voltages} - -The current flowing though the -whole circuit can be measured on the PCB by reading a third -sense voltage from one of the load resistors. Knowing the current flowing -through the circuit -and knowing the voltage drop over the PT100, we can calculate its -resistance by ohms law $V=I.R$, $R=\frac{V}{I}$. -Thus a little loss of supply current due to resistance in the cables -does not impinge on accuracy. -The resistance to temperature conversion is achieved -through the published PT100 tables\cite{eurothermtables}. - -\section{Safety case for 4 wire circuit} - -This sub-section looks at the behaviour of the PT100 four wire circuit -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}. -Thus for each component, an analysis is made for each of it failure modes, -with respect to its effect on the -circuit. Each one of these scenarios is termed a `test case'. -The resultant circuit behaviour for each of these test cases is noted. -The worst case for this type of -analysis would be a fault that we cannot detect. -Where this occurs a circuit re-design is probably the only sensible course of action. - - - -\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}. -%Should wires become disconnected these will have the same effect as -%given resistors going open. -For the purpose of this analyis; -$R_{1}$ is the \ohms{2k2} from 5V to the thermistor, -$R_3$ is the PT100 thermistor and $R_{2}$ connects the thermistor to ground. - -We can define the terms `High Fault' and `Low Fault' here, with reference to figure -\ref{fig:pt100vrange}. Should we get a reading outside the safe green zone -in the diagram we can consider this a fault. -Should the reading be above its expected range this is a `High Fault' -and if below a `Low Fault'. - -Table \ref{ptfmea} plays through the scenarios of each of the resistors failing -in both SHORT and OPEN failure modes, and hypothesises an error condition in the readings. -The range {0\oc} to {300\oc} will be analysed using potential divider equations to -determine out of range voltage limits in section \ref{ptbounds}. - -\begin{table}[ht] -\caption{PT100 FMEA Single Faults} % title of Table -\centering % used for centering table -\begin{tabular}{||l|c|c|l|l||} -\hline \hline - \textbf{Test} & \textbf{Result} & \textbf{Result } & \textbf{General} \\ - \textbf{Case} & \textbf{sense +} & \textbf{sense -} & \textbf{Symtom Description} \\ -% R & wire & res + & res - & description -\hline -\hline - $R_1$ SHORT & High Fault & - & Value Out of Range Value \\ \hline -$R_1$ OPEN & Low Fault & Low Fault & Both values out of range \\ \hline - \hline -$R_3$ SHORT & Low Fault & High Fault & Both values out of range \\ \hline - $R_3$ OPEN & High Fault & Low Fault & Both values out of range \\ \hline -\hline -$R_2$ SHORT & - & Low Fault & Value Out of Range Value \\ - $R_2$ OPEN & High Fault & High Fault & Both values out of range \\ \hline -\hline -\end{tabular} -\label{ptfmea} -\end{table} - -From table \ref{ptfmea} it can be seen that any component failure in the circuit -should cause a common symptom, that of one or more of the values being `out of range'. -Temperature range calculations and detailed calculations -on the effects of each test case are found in section \ref{pt100range} -and \ref{pt100temp}. - - - -\subsection{Range and PT100 Calculations} -\label{pt100temp} -PT100 resistors are designed to -have a resistance of \ohms{100} at {0\oc} \cite{aoe},\cite{eurothermtables}. -A suitable `wider than to be expected range' was considered to be {0\oc} to {300\oc} -for a given application. -According to the Eurotherm PT100 -tables \cite{eurothermtables}, this corresponded to the resistances \ohms{100} -and \ohms{212.02} respectively. From this the potential divider circuit can be -analysed and the maximum and minimum acceptable voltages determined. -These can be used as bounds results to apply the findings from the -PT100 FMEA analysis in section \ref{fmea}. - -As the PT100 forms a potential divider with the \ohms{2k2} load resistors, -the upper and lower readings can be calculated thus: - - -$$ highreading = 5V.\frac{2k2+pt100}{2k2+2k2+pt100} $$ -$$ lowreading = 5V.\frac{2k2}{2k2+2k2+pt100} $$ -So by defining an acceptable measurement/temperature range, -and ensuring the -values are always within these bounds we can be confident that none of the -resistors in this circuit has failed. - -To convert these to twelve bit ADC (\adctw) counts: - -$$ highreading = 2^{12}.\frac{2k2+pt100}{2k2+2k2+pt100} $$ -$$ lowreading = 2^{12}.\frac{2k2}{2k2+2k2+pt100} $$ - - -\begin{table}[ht] -\caption{PT100 Maximum and Minimum Values} % title of Table -\centering % used for centering table -\begin{tabular}{||c|c|c|l|l||} -\hline \hline - \textbf{Temperature} & \textbf{PT100 resistance} & -\textbf{Lower} & \textbf{Higher} & \textbf{Description} \\ -\hline -% {-100 \oc} & {\ohms{68.28}} & 2.46V & 2.53V & Boundary of \\ -% & & 2017\adctw & 2079\adctw & out of range LOW \\ \hline - {0 \oc} & {\ohms{100}} & 2.44V & 2.56V & Boundary of \\ - & & 2002\adctw & 2094\adctw & out of range LOW \\ \hline - {+300 \oc} & {\ohms{212.02}} & 2.38V & 2.62V & Boundary of \\ - & & 1954\adctw & 2142\adctw & out of range HIGH \\ \hline -\hline -\end{tabular} -\label{ptbounds} -\end{table} - -Table \ref{ptbounds} gives ranges that determine correct operation. In fact it can be shown that -for any single error (short or opening of any resistor) this bounds check -will detect it. - - -\section{Single Fault FMEA Analysis \\ of PT100 Four wire circuit} - -\subsection{Single Fault Modes as PLD} - -The component~failure~modes in table \ref{ptfmea} can be represented as contours -on a PLD diagram. -Each test case, is defined by the contours that enclose -it. The test cases here deal with single faults only -and are thus enclosed by one contour each. - - -\begin{figure}[h] - \centering - \includegraphics[width=400pt,bb=0 0 518 365,keepaspectratio=true]{./pt100/pt100_tc.jpg} - % pt100_tc.jpg: 518x365 pixel, 72dpi, 18.27x12.88 cm, bb=0 0 518 365 - \caption{PT100 Component Failure Modes} - \label{fig:pt100_tc} -\end{figure} - -This circuit supplies two results, sense+ and sense- voltage readings. -To establish the valid voltage ranges for these, and knowing our -valid temperature range for this example ({0\oc} .. {300\oc}) we can calculate -valid voltage reading ranges by using the standard voltage divider equation \ref{eqn:vd} -for the circuit shown in figure \ref{fig:vd}. - - -\begin{figure}[h] - \centering - \includegraphics[width=100pt,bb=0 0 183 170,keepaspectratio=true]{./pt100/voltage_divider.png} - % voltage_divider.png: 183x170 pixel, 72dpi, 6.46x6.00 cm, bb=0 0 183 170 - \caption{Voltage Divider} - \label{fig:vd} -\end{figure} -%The looking at figure \ref{fig:vd} the standard voltage divider formula (equation \ref{eqn:vd}) is used. - -\begin{equation} -\label{eqn:vd} - V_{out} = V_{in}.\frac{Z2}{Z2+Z1} -\end{equation} - - - -\subsection{Proof of Out of Range \\ Values for Failures} -\label{pt110range} -Using the temperature ranges defined above we can compare the voltages -we would get from the resistor failures to prove that they are -`out of range'. There are six test cases and each will be examined in turn. - -\subsubsection{ TC1 : Voltages $R_1$ SHORT } -With pt100 at 0\oc -$$ highreading = 5V $$ -Since the highreading or sense+ is directly connected to the 5V rail, -both temperature readings will be 5V.. -$$ lowreading = 5V.\frac{2k2}{2k2+100\Omega} = 4.78V$$ -With pt100 at the high end of the temperature range 300\oc. -$$ highreading = 5V $$ -$$ lowreading = 5V.\frac{2k2}{2k2+212.02\Omega} = 4.56V$$ - -Thus with $R_1$ shorted both readingare outside the -proscribed range in table \ref{ptbounds}. - -\subsubsection{ TC2 : Voltages $R_1$ OPEN } - -In this case the 5V rail is disconnected. All voltages read are 0V, and -therefore both readings are outside the -proscribed range in table \ref{ptbounds}. - - -\subsubsection{ TC 3 : Voltages $R_2$ SHORT } - -With pt100 at 0\oc -$$ lowreading = 0V $$ -Since the lowreading or sense- is directly connected to the 0V rail, -both temperature readings will be 0V. -$$ lowreading = 5V.\frac{100\Omega}{2k2+100\Omega} = 0.218V$$ -With pt100 at the high end of the temperature range 300\oc. -$$ highreading = 5V $$ -$$ lowreading = 5V.\frac{212.02\Omega}{2k2+212.02\Omega} = 0.44V$$ - -Thus with $R_2$ shorted both readings are outside the -proscribed range in table \ref{ptbounds}. - -\subsubsection{ TC : 4 Voltages $R_2$ OPEN } -Here there is no potential divider operating and both sense lines -will read 5V, outside of the proscribed range. - - -\subsubsection{ TC 5 : Voltages $R_3$ SHORT } - -Here the potential divider is simply between -the two 2k2 load resistors. Thus it will read a nominal; -2.5V. - -Assuming the load resistors are -precision components, and then taking an absolute worst case of 1\% either way. - -$$ 5V.\frac{2k2*0.99}{2k2*1.01+2k2*0.99} = 2.475V $$ - -$$ 5V.\frac{2k2*1.01}{2k2*1.01+2k2*0.99} = 2.525V $$ - -These readings both lie outside the proscribed range. -Also the sense+ and sense- readings would have the same value. - -\subsubsection{ TC 6 : Voltages $R_3$ OPEN } - -Here the potential divider is broken. The sense- will read 0V and the sense+ will -read 5V. Both readings are outside the proscribed range. - -\subsection{Summary of Analysis} - -All six test cases have been analysed and the results agree with the hypothesis -put in Table \ref{ptfmea}. The PLD diagram, can now be used to collect the -symptoms. In this case there is a common and easily detected symptom for all these single -resistor faults : Voltage out of range. - -A spider can be drawn on the PLD diagram to this effect. - -In practical use, by defining an acceptable measurement/temperature range, -and ensuring the -values are always within these bounds we can be confident that none of the -resistors in this circuit has failed. - - -\begin{figure}[h] - \centering - \includegraphics[width=400pt,bb=0 0 518 365,keepaspectratio=true]{./pt100/pt100_tc_sp.jpg} - % pt100_tc.jpg: 518x365 pixel, 72dpi, 18.27x12.88 cm, bb=0 0 518 365 - \caption{PT100 Component Failure Modes} - \label{fig:pt100_tc_sp} -\end{figure} - - -The PT100 circuit can now be treated as a component in its own right, and has one failure mode, -{\textbf OUT\_OF\_RANGE}. It can now be represnted as a PLD see figure \ref{fig:pt100_singlef}. - -\begin{figure}[h] - \centering - \includegraphics[width=100pt,bb=0 0 167 194,keepaspectratio=true]{./pt100/pt100_singlef.jpg} - % pt100_singlef.jpg: 167x194 pixel, 72dpi, 5.89x6.84 cm, bb=0 0 167 194 - \caption{PT100 Circuit Failure Modes : From Single Faults Analysis} - \label{fig:pt100_singlef} -\end{figure} - - - - -%Interestingly we can calculate the failure statistics for this circuit now. -%Mill 1991 gives resistor stats of ${10}^{11}$ times 6 (can we get special stats for pt100) ??? -\clearpage -\subsection{Mean Time to Failure} - -Using the MIL1991\cite{mil1991} specifications for resistor and thermistor -failure statistics we calculate the reliability of this circuit. -MIL1991 gives MTTF for a wide range of common components. -It does not specify how the components will fail (in this case OPEN or SHORT). {Some standards, notably EN298 only consider resistors failing in OPEN mode}. -FMD-97 Gives 27\% OPEN and 3\% SHORTED, for resistors under certain electrical and environmental stresses. This example -compromises and uses a 90:10 ratio, for resistor failure. -Thus for this example resistors are expevcted to fail OPEN in 90\% of cases and SHORTED -in the other 10\%. - -A standard fixed film resistor, for use in a benign environment, non military spec at -temperatures up to 60\oc is given a probability of 13.8 failures per billion ($10^9$) -hours of operation. This figure is referred to as a FIT\footnote{FIT values are measured as the number of failures per billion hours of operation, (roughly 1.1 Million years). The smaller the FIT number the more reliable the fault~mode}, Failure in time. - -A thermistor, bead type, non military spec is given a FIT of 3150. - -Using the RIAC finding we can draw up the following table (table \ref{tab:stat_single}), -showing the FIT values for all faults considered. - - - -\begin{table}[h+] -\caption{PT100 FMEA Single // Fault Statistics} % title of Table -\centering % used for centering table -\begin{tabular}{||l|c|c|l|l||} -\hline \hline - \textbf{Test} & \textbf{Result} & \textbf{Result } & \textbf{MTTF} \\ - \textbf{Case} & \textbf{sense +} & \textbf{sense -} & \textbf{per $10^9$ hours of operation} \\ -% R & wire & res + & res - & description -\hline -\hline -TC:1 $R_1$ SHORT & High Fault & - & 12.42 \\ \hline -TC:2 $R_1$ OPEN & Low Fault & Low Fault & 1.38 \\ \hline - \hline -TC:3 $R_3$ SHORT & Low Fault & High Fault & 2835 \\ \hline -TC:4 $R_3$ OPEN & High Fault & Low Fault & 315 \\ \hline -\hline -TC:5 $R_2$ SHORT & - & Low Fault & 12.42 \\ -TC:6 $R_2$ OPEN & High Fault & High Fault & 1.38 \\ \hline -\hline -\end{tabular} -\label{tab:stat_single} -\end{table} - -The FIT for the circuit as a whole is the sum of MTTF values for all the -test cases. The PT100 circuit here has a FIT of 3177.6. This is a MTTF of -about 360 years per circuit. - -A Probablistic tree can now be drawn, with a FIT value for the PT100 -circuit and FIT values for all the component fault modes that it was calculated from. -We can see from this that that the most likely fault is the thermistor going OPEN. -This circuit is 8 times more likely to fail in this way than in any other. -Were we to need a more reliable temperature sensor this would probably -be the fault~mode we would scrutinise first. - - -\begin{figure}[h+] - \centering - \includegraphics[width=400pt,bb=0 0 856 327,keepaspectratio=true]{./pt100/stat_single.jpg} - % stat_single.jpg: 856x327 pixel, 72dpi, 30.20x11.54 cm, bb=0 0 856 327 - \caption{Probablistic Fault Tree : PT100 Single Faults} - \label{fig:stat_single} -\end{figure} - - -The PT100 analysis presents a simple result for single faults. -The next analysis phase looks at how the circuit will behave under double simultaneous failure -conditions. - -\clearpage -\section{ PT100 Double Simultaneous \\ Fault Analysis} - -% typeset in {\Huge \LaTeX} \today - diff --git a/standards/standards_paper.tex b/standards/standards_paper.tex index e4fa253..783735b 100644 --- a/standards/standards_paper.tex +++ b/standards/standards_paper.tex @@ -1,18 +1,50 @@ % % Make the revision and doc number macro's then they are defined in one place +\ifthenelse {\boolean{paper}} +{ \begin{abstract} This chapter describes the legal frameworks and standards organisations that exist in Europe and North America. Some specific standards (that the author has experience with directly) are reviewed. \end{abstract} +} +{} \section{Introduction} -\section{European Safety Standards Legal Framework} -\section{North American Legal Framework} +\subsection{Product Life Cycle} +i +difffernent areas +EN61508 REQ to SPEC to DESIGN + + +EN298 +DESIGN TO PRODUCT + +FM +PRODUCT VERIFICATION MONITORING + +Different agencies - approval is testing of new product +and verification to standard - manufacturing overwatch / supervision +word on tip of tounge - + +\section{European or `EN' Standards} + +\subsection{Scope} +\subsection{Approval Process} +\subsection{Legal Framework} +\subsection{References} + +\section{North American Standards} + +\subsection{Scope} +\subsection{Approval Process} +\subsection{Legal Framework} +\subsection{References} + Protection against being sued mainly ! UL - underwriters laboratories.... etc @@ -21,10 +53,10 @@ Protection against being sued mainly ! UL - underwriters laboratories.... etc Stabndards of ten reference other - i.e. EMC testing in EN298 refers toEN blah blah to level blah blah -\section{EN298} +\section{Standard in detail: EN298} -\section{UL1998} +\section{Standard in detail: UL1998} -\section{EN230} +\section{Standard in detail: EN230} -\section{EN61508} +\section{Standard in detail: EN61508} diff --git a/symptom_ex_process/mybib.bib b/symptom_ex_process/mybib.bib deleted file mode 100644 index b996d80..0000000 --- a/symptom_ex_process/mybib.bib +++ /dev/null @@ -1,153 +0,0 @@ - - -% my bib file. - - -% $Id: mybib.bib,v 1.2 2008/09/26 16:31:31 robin Exp $ - - -@ARTICLE{valueoflife, - AUTHOR = "W.K. Viscusi", - TITLE = "The value of life: Estimates with risks by occupation and industry", - JOURNAL = "Harvard John M. Olin Canter for Law ISSN 1045-6333", - YEAR = "2003" -} - - -@ARTICLE{nucfta, - AUTHOR = "US Nuclear reg commission", - TITLE = "Fault Tree Handbook", - JOURNAL = "Nuclear Safety Analysis Handbook", - YEAR = "1981" -} - -@ARTICLE{nasafta, - AUTHOR = "NASA", - TITLE = "Fault Tree Handbook with Aerospace Applications", - JOURNAL = "NASA Handbook", - YEAR = "2002" -} - - -@BOOK{mil1991, - AUTHOR = "United~States~DOD", - TITLE = "Reliability Prediction of Electronic Equipment", - PUBLISHER = "DOD", - YEAR = "1991" -} - - -@BOOK{sccs, - AUTHOR = "Neil~Storey", - TITLE = "Safety-Critical Computer Systems ISBN 0-201-42787-7", - PUBLISHER = "Prentice Hall", - YEAR = "1996" -} - -@BOOK{sem, - AUTHOR = "J.~Woodcock,~Martin~Loomes", - TITLE = "Software Engineering Mathematics ISBN 0-273-02673-9", - PUBLISHER = "Pitman", - YEAR = "1988" -} - -@BOOK{f77, - AUTHOR = "A.~Balfour D.H.~Marwick", - TITLE = "Programming in Standard Fortran 77 ISBN 0-435-77486-7", - PUBLISHER = "Heinemann Educational Books", - YEAR = "1979" -} - -@BOOK{ctw, - AUTHOR = "Gregory~J.E.~Rawlins", - TITLE = "Compared to What ? An introduction to the analysis of algorithms ISBN 0-7167-8243-x", - PUBLISHER = "Computer Science Press", - YEAR = "1991" -} - - - -@BOOK{alg, - AUTHOR = "Alan~Gibbons", - TITLE = "Algorithmic Graph Theory ISBN 0-521-28881-9", - PUBLISHER = "Cambridge University Press", - YEAR = "1985" -} - -@BOOK{found, - AUTHOR = "Ian~Stewart, David~Tall", - TITLE = "The Foundations of Mathematics : ISBN 0-19-853165-6", - PUBLISHER = "Oxford University Press", - YEAR = "1977" -} - -@BOOK{shin, - AUTHOR = "Sun-Joo~Shin", - TITLE = "The Iconic Logic of Peirces Graphs", - PUBLISHER = "Bradford", - YEAR = "2002" -} - - -@BOOK{idmfssz, - AUTHOR = " D~C~Ince", - TITLE = " An Introduction to Discrete Mathematics, Formal System Specification and Z : Oxford : ISBN 0-19-853836-7", - PUBLISHER = "Oxford University Press", - YEAR = "1988" -} - - -@BOOK{wdycwopt, - AUTHOR = " Richard~P~Feynman", - TITLE = " What do you care what other people think: Harper Collins : ISBN 0-586-21855-6", - PUBLISHER = " harpercollins", - YEAR = "1988" -} - - -@MISC{gnuplot, - author = "Various Open~source~Project", - title = "GNUPlot 4 Home Page", - howpublished = "Available from http://www.gnuplot.info/", - year = "2005" -} - -@MISC{eulerviz, - author = "Peter~Rodgers, John~Howse, Andrew~Fish", - title = "Visualization of Euler Diagrams", - howpublished = "http://www.cmis.bton.ac.uk/research/vmg/papers/EulerViz.pdf", - year = "2005" -} - -@MISC{eulerprop, - author = "Peter~Rodgers, John~Howse, Gem~Stapleton", - title = "Properties of Euler Diagrams", - howpublished = "http://www.cmis.bton.ac.uk/research/vmg/papers/", - year = "2007" -} -@MISC{en298, - author = "E N Standard", - title = "Gas Burner Controllers with forced draft", - howpublished = "EN298", - year = "2003" -} - -@MISC{en61508, - author = "E N Standard", - title = "Functional safety of electrical/electronic/programmable electronic safety related systems", - howpublished = "EN61508", - year = "2002" -} -@MISC{javaarea, - author = "Sun~Micro~Systems", - title = "Java Area Operations", - howpublished = "Available from http://java.sun.com/j2se/1.3/docs/api/java/awt/geom/Area.html", - year = "2000" -} -@MISC{javaarea, - author = "Sun~Micro~Systems", - title = "Java Area Operations", - howpublished = "Available from http://java.sun.com/j2se/1.3/docs/api/java/awt/geom/Area.html", - year = "2000" -} -