Added ASIL subsection

mybib.bib

@@ -306,7 +306,7 @@ ISSN={Doi:10.1145/2330667.2330683},}
  issn = {1022-7091},
  pages = {459--475},
  numpages = {17},
- url = {http://dl.acm.org/citation.cfm?id=590564.590572},
+ url = {http://dl.acm.org/citation.cfm\?id=590564.590572},
  acmid = {590572},
  publisher = {J. C. Baltzer AG, Science Publishers},
  address = {Red Bank, NJ, USA},
@@ -672,6 +672,35 @@ ISSN={0149-144X},}
   YEAR =         "2004"
 }
 
+@INPROCEEDINGS{6464473,
+author={Ward, D.D. and Crozier, S.E.},
+booktitle={System Safety, incorporating the Cyber Security Conference 2012, 7th IET International Conference on},
+title={The uses and abuses of ASIL decomposition in ISO 26262},
+year={2012},
+pages={1-6},
+keywords={automotive electrics;automotive electronics;},
+doi={10.1049/cp.2012.1523},
+}
+
+@article{Kafka20122,
+title = "The Automotive Standard ISO 26262, the Innovative Driver for Enhanced Safety Assessment; Technology for Motor Cars ",
+journal = "Procedia Engineering ",
+volume = "45",
+number = "0",
+pages = "2 - 10",
+year = "2012",
+note = "2012 International Symposium on Safety Science and Technology",
+issn = "1877-7058",
+doi = "http://dx.doi.org/10.1016/j.proeng.2012.08.112",
+url = "http://www.sciencedirect.com/science/article/pii/S1877705812031244",
+author = "Peter Kafka",
+keywords = "Historical perspective",
+keywords = "main normative items",
+keywords = "Functional unit and functional safety",
+keywords = "Hardware and software assessment",
+keywords = "Life cycle considerations",
+keywords = "Impact on safety assessment performed in automotive industry "
+}
 
 @ARTICLE{bubba,
   AUTHOR =       "Ron Mancini",

submission_thesis/CH2_FMEA/copy.tex

@@ -1457,12 +1457,55 @@ The overall aim of SIL is to classify the safety of a system,
 by statistically determining how frequently it can fail dangerously.
 \fmmdglossFMEDA
 %
+\subsection{Automotive Safety Integrity Levels}
 %
-%\subsection{ FMEDA - Failure Modes Effects and Diagnostic Analysis}
-%\subsection{ FMEDA - Failure Modes Effects and Diagnostic Analysis}
-%FMEA can be used as a term simple to mean Failure Mode Effects Analysis, and is
-%part of product approval for many regulated products in the EU and the USA...
+\label{sec:asil}
 %
+The EN61508 variant for automotive use, as defined in standard ISO~26262, is known as the Automotive SIL (ASIL)~\cite{Kafka20122}.
+%
+Safety instrumented functions (SIFs) for vehicles are assigned ASIL ratings.
+%
+ASIL classifications are rated from A to D, where D is the most safety critical.
+%
+For instance very critical functions such as the brakes and steering will have the highest ASIL rating of D.
+%
+The automotive industry generally uses bought in modules % which must have been tested and approved, 
+typically built by specialist companies.
+%
+These modules themselves must have been tested and approved so, for a car manufacturer
+designing from scratch is not generally financially feasible.
+%
+This means that to implement an ASIL SIF designers  will usually have to rely on bought in modules. 
+%
+However, these bought in modules may not be rated to the ASIL level required by the SIF.
+%  %
+% ASIL functions are therefore often implemented in a modular fashion.
+%
+Because of the modular paradigm  forced on the designers by having to buy in components
+a process has been developed called `ASIL~de-composition'~\cite{6464473}.
+%
+This allows a highly safety critical function to be implemented
+with lower ASIL rated components, as long as it can be shown that they
+have independent failure causes and implement redundancy. % for the SIF.
+%
+This is in effect a top down de-composition of safety requirements.
+%
+This is rather like the demand for multiple engines on an aircraft
+that must make a long journeys over the sea to statistically limit
+the likelihood of one failure cause --- i.e. one engine failure --- causing a serious incident.
+%
+The drawback to this redundancy concept is an unexpected common failure mode~\cite{allfour}.
+%
+The ASIL philosophy does represent a modular approach to safety analysis.
+%
+This makes it of interest to this study, which later proposes a modular failure mode analysis methodology.
+%
+
+
+
+
+
+
 \section{FMEA used for Safety Critical Approvals}
 \fmmdglossDFMEA
 \subsection{DESIGN FMEA: Safety Critical Approvals FMEA}
@@ -1482,6 +1525,8 @@ judged to be in critical sections of the product.
 This could be considered as a design check method, deliberately
 looking for weaknesses at a theoretical level.
 %
+Because design FMEA meetings can have the format of a meeting and discussion
+it can have the following drawbacks:
 %\subsection{DESIGN FMEA: Safety Critical Approvals FMEA}
 %
 % \begin{figure}[h]