公开(公告)号：US11307569B2

公开(公告)日：2022-04-19

申请号：US16282087

申请日：2019-02-21

Applicant: Oracle International Corporation

Inventor： Kenny C. Gross ,  Ashin George ,  DeJun Li

IPC: G05B23/02 ,  G06N5/04 ,  G06K9/62 ,  G06N7/00 ,  G06Q10/06

Abstract: The system receives a set of present time-series signals gathered from sensors in the asset. Next, the system uses an inferential model to generate estimated values for the set of present time-series signals, and performs a pairwise differencing operation between actual values and the estimated values for the set of present time-series signals to produce residuals. The system then performs a sequential probability ratio test (SPRT) on the residuals to produce SPRT alarms with associated tripping frequency (TF). While the TF exceeds a TF threshold, the system iteratively adjusts sensitivity parameters for the SPRT to reduce the TF, and performs the SPRT again on the residuals. The system then uses a logistic regression model to compute a risk index for the asset based on the TF. If the risk index exceeds a threshold, the system generates a notification indicating that the asset needs to be replaced.

公开(公告)号：US20200218801A1

公开(公告)日：2020-07-09

申请号：US16244006

申请日：2019-01-09

Applicant: Oracle International Corporation

Inventor： Kenny C. Gross ,  Ashin George

IPC: G06F21/55 ,  G06N20/00 ,  G06N7/00

Abstract: The disclosed embodiments relate to a system that determines whether an inferential model is susceptible to spillover false alarms. During operation, the system receives a set of time-series signals from sensors in a monitored system. The system then trains the inferential model using the set of time-series signals. Next, the system tests the inferential model for susceptibility to spillover false alarms by performing the following operations for one signal at a time in the set of time-series signals. First, the system adds degradation to the signal to produce a degraded signal. The system then uses the inferential model to perform prognostic-surveillance operations on the time-series signals with the degraded signal. Finally, the system detects spillover false alarms based on results of the prognostic-surveillance operations.