The definition of PMC equation model (that is equation description of PMC model)was first set up.PMC model is a kind of most common system-level fault model.Owing to the characteristics that traditional graph theory diagnosis algorithm couldn't be without "

t

-diagnosabe" and "believe the most" (that is supposing the number of fault processors less than half the number of all processors in the system)

the concepts of "absolute fault base"etc.were defined

and the tool of "body grouping"was fully wielded

finally a concrete method——equation diagnosis algorithm was found

on seeking all consistent fault patterns for the class of models without supposing "

t

-diagnosable" or "believe the most".