\ifthenelse {\boolean{paper}} { \abstract{ %% What I have done %% %% What I have found %% %% Sell it %% } } { %%% CHAPTER INTO NEARLT THE SAME AS ABSTRACT \section{Introduction} This chapter %% What I have done %% %% What I have found %% %and considering some constraints determined from %the evaluation of the four established methodologies, %% Sell it %% } %{ \huge This might become a chapter in its own right after fmmdset } \section{From UML Model to Object Model} Let us consider a theoretical FMMD model. For the sake of simplicity consider that all components and functional groups have only two failure modes that we will label $a$ and $b$. We can start with some base components, of types C and K say, $\{ C_1, C_2, C_3, K_4, C_5, C_6, K_7 \}$. Thus applying the function $fm$ to any of the components gives error modes identified by a or b. For the sake of example, let us say that each component has two failure modes $a$ and $b$. So the function $fm$ applied to $C_1$ yields $C_{1 a}$ and $C_{1 b}$: i.e. $fm(C_1) = \{ C_{1 a}, C_{1 b} \}$. HOW UML OBJECT MODEL OF COMPONENT AND ITS ERROR MODES \ifthenelse {\boolean{paper}} { We can organise these into functional groups (where the superscript represents the FMMD hierarchy level, or $\alpha$ value, thus: } { We can organise these into functional groups (where the superscript represents the $\alpha$ value, see section \ref{alpha}), thus: } $$ FG^0_1 = \{C_1, C_2\},$$ $$ FG^0_2 = \{C_1, C_3, K_4\},$$ $$ FG^0_3 = \{C_5, C_6, K_7\}.$$ Note that in this model the base~component $C_1$ has been used in two separate functional groups. Also that the component type $K$ has been used by two different functional groups. \paragraph{Symptom Extraction.} A processes of symptom extraction is now applied to the functional groups. Again for the sake of example, let us say that each functional group has one or two symptoms again subscripted by $a$ and $b$. Applying symptom abstraction to $FG^0_1$ i.e. $\bowtie fm ( FG^0_1 ) = \{ FG^0_{1 a}, FG^0_{1 b} \} $ We can now create a new derived component, $DC^1_1$, whose failure modes are the symptoms of $FG^0_1 $ thus $ fm ( {DC}^1_1 ) = \{ FG^0_{1 a}, FG^0_{1 b} \} $. UML OBJECT MODEL OF DERIVED COMPONENT TOO \subsection{Using Derived Components in Functional Groups} HERE should how the hierarchy is built, how the inheritance works etc HAVE an example. totally theoretical. HAVE Common mode failure detection AND Common dependency detection \subsection{Directed Acyclic Graph} Show how the hierarchy can be represented as a DAG draw a dag \subsection{Traversing the datamodel} Show how we can find multiple causes for a SYSTEM level error \subsubsection{Common mode failure detection} Describe what a common mode failure is. show how common mode failures can be detected by using the parts list (same components can all have their error modes turned on, and the effect can be seen on the system, automatically tracing common mode failures. \subsubsection{Common dependency detection} The same component can be relied on by different functional groups within a system For instance a power supply spur (i.e. supplying a particular isolated voltage say) could have many functional groups depending or linked to its failure modes. Show how FMMD makes this tracable % clear the page if its a paper to keep the diagram out of the references \ifthenelse {\boolean{paper}} { \clearpage } { } \section{Current Static Failure Mode Methodologies} \ifthenelse {\boolean{paper}} { paper } { chapter } \vspace{60pt} \today