Internal engine

Results access

To access to the propagation results generated by the internal engine :

  1. In the Project Explorer view, open the folder propagation / InternalEngine
  2. Select the right folder corresponding to the wanted analysis. The folder name contains the analysis date and time, to be able to find it easily
  3. Select the result file corresponding to the wanted feared event
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  5. Open the file to display the generated fault tree : 
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  7. To expand only one node, click on the on the left of each node.
  8. To expand or collapse the whole tree, click on the corresponding button in the editor tool bar  :
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Propagation rules

The global analysis use some rules to define how the failures are propagated between the components, according to the failure modes used. Thus, these rules define if a failure is propagated from a failure mode to an other, following the data links between the components ports. Here are the existing rules :

Source failure mode  \ Target failure mode
Absent Untimely Erroneous Specific erroneous No effect
Absent X



Untimely
X


Erroneous

X X
Specific erroneous


X
No effect




For example :

Specific behaviour

Loop management

During the propagation, some loops can be found. A loop is detected when on a branch the same failure item is found twice.

There is two kinds of loop :

When a loop is detected, the propagation is stopped on the current branch. This information is shown in propagation tree by a loop icon :

Internal engine preferences

To open the internal engine preferences page, click on Window > Preferences > Global Analysis > Propagation > Internal Engine

Propagation limit

This option is the maximum of node elements kept by the propagation. If this limitation is reached before the propagation ended, the propagation will be stopped.

Be careful : This value has a direct impact on memory print of Eclipse Safety Framework and on your propagation results.

Feared events association inheritance

Behaviour

When the global analysis is performed with the internal engine on a feared events family, the failure modes associated to this family will inherit of all the feared events linked to this family. 

Example

Let the following library :


If the feared events and feared events families associations is the following :

Then the propagation result performed on the F1 family will be :

Indeed, the inheritance has been applied like this :