FITrate description?

[Lei Chen]

Hi experts,
I read the "Eversholt FaultTree Description Language"
manual(version 1.8). Several properties are applicable to fault event,
which are listed in table 2-1. All the properties except FITrate are
explained in detail underlying the table. Then what does the FITrate
property mean? For example, specifically, what is the effect of
FITrate=10 in the event declaration of " event
***@acside/pdb, FITrate=10;"? Forgive me for the
maybe silly question, I can't find a place explaining it.

Thanks,
Lei Chen

[Steve Hanson]

Hi Lei,

Post by Lei Chen
Hi experts,
I read the "Eversholt FaultTree Description Language"
manual(version 1.8). Several properties are applicable to fault event,
which are listed in table 2-1. All the properties except FITrate are
explained in detail underlying the table.

You're right, it does seem to be missing. I'd better fix that.

Post by Lei Chen
Then what does the FITrate property mean? For example, specifically,
what is the effect of FITrate=10 in the event declaration of " event
maybe silly question, I can't find a place explaining it.

Basically it tells you the relative frequency at which faults of a
particular class are expected to be seen on a particular resource.

It is only used for multi-entry suspect lists to allow calculation of
relative probabilities for each suspect in the suspect list. So if you
have two suspects, one with a FITrate of 100 and one with a FITrate of
300, then the "certainty" fields added to the suspect are 25% and 75%
respectively (as the latter is deemed 3 times more likely to occur).
Note again that the FITrate fields are only relative to each other. If
no FITrate property is present then all suspects in the list are given
equal probability.

Steve

Post by Lei Chen
Thanks,
Lei Chen
_______________________________________________
fm-discuss mailing list