Download justifying software systems safety using arguments

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CHAPTER 6. TESTING AND VALIDATION
Figure 6.1: Autonomous vehicle scenario.
Table 6.1: Retrieving some information about the safety case represented in figure 6.1.
Query
Top level goal
Support goals
Evidence supporting goal g2
Undeveloped Goals
Check if Abox is consistent
Get all contexts of a specific
goal
RacerPro query
RacerPro
answer
(concept − instances TopLevelGoal )
g1
(concept − instances SupportGoal )))
g2 , g3 , g4 , g5
(retrieve − individual − fillers g2 has − evidence) e1 , e2 , e3 , e4
(concept − instances UndevelopedGoals)
g3 , g4 , g5
(abox − consistent?)
(individual − fillers g1 inContextOf )
c1 , c2
The second safety case is taken from medical industry and refers to the Therac 25,
a case study in safety failure. In figure 6.4 is a diagram build wit our tool representing
the case of Therac 25 presented in [12].