GEMINI-a logic system for fault diagnosis based on set functions

A logic system is described which is based on images and inverse images of sets under functions designed specifically to deduce logic values in circuits under multiple fault conditions. Pairs, or larger clusters, of input vectors are analyzed in a two-phase algorithm. First, in forward propagation, the sets of possible values (images) for all lines of a diagnosed circuit are determined. Next, in backward implication, the sets of values on internal lines are deduced (inverse images) based on the observed response. Any fault producing a value that does not belong to these sets is tested unconditionally.<>