Patent ID: 7567878

Claim:
A method for evaluating an anomaly measurement x′ in a machine condition monitoring system including a processor, wherein measurements x i are evaluated in a one-class classifier having a decision region R 1 for the class C 1 such that an evaluation function ƒ(x) is greater than or equal to a threshold T for a measurement x within the region, and less than T outside the region the method comprising the steps of: training the one-class classifier to establish the decision region R 1 from a set of training samples {x 1 , x 2 , . . . , x N }; receiving the anomaly measurement x′; determining that the anomaly measurement is outside the region R 1 ; determining, using the processor, a distance from the measurement x′ to a boundary of the region R 1 ; and evaluating the anomaly measurement x′ based on the distance; wherein the step of determining a distance from the measurement x′ to the region R 1 further comprises the steps of: finding a closest sample q, in the region R 1 , to the measurement x′; defining an average point m between the x′ and q; if a difference between ƒ(m) and T is greater than a permissible error, then if ƒ(m)<T, assign m to x′ and return to the defining step; and if ƒ(m)>T, assign m to q and return to the defining step; and if the difference is less than the permissible error, assigning a distance from the measurement x′ to m as the distance from the measurement x′ to a boundary of the region R 1 .