Dual sensitivity mode system for monitoring processes and sensors

• US 6,107,919 A
• Filed: 02/24/1999
• Issued: 08/22/2000
• Est. Priority Date: 02/24/1999
• Status: Expired due to Term

• Current Assignee: ARCH Development Corporation (University of Chicago)
• Original Assignee: ARCH Development Corporation (University of Chicago)
• Inventors: Wegerich, Stephan W., Gross, Kenneth C., Wilks, Alan D.
• Primary Examiner(s): POPE, DARYL C
• Application Number:
  US09/256,884
• Time in Patent Office: 545 Days
• Field of Search: 340/514, 340/506, 340/511, 340/825.06, 324/527, 324/528
• US Class Current: 340/511
• CPC Class Codes: G08B 29/22 Provisions facilitating manual calibration, e.g. input or output provisions for testing; Holding of intermittent values to permit measurement

Abstract

A method and system for analyzing a source of data. The system and method involves initially training a system using a selected data signal, calculating at least two levels of sensitivity using a pattern recognition methodology, activating a first mode of alarm sensitivity to monitor the data source, activating a second mode of alarm sensitivity to monitor the data source and generating a first alarm signal upon the first mode of sensitivity detecting an alarm condition and a second alarm signal upon the second mode of sensitivity detecting an associated alarm condition. The first alarm condition and second alarm condition can be acted upon by an operator and/or analyzed by a specialist or computer program.

Claims

1. A method of analyzing a data source, comprising the steps of:

training a system using a desired data signal, the training including the step of calculating at least two levels of alarm sensitivity and associated pattern recognition parameters using a pattern recognition methodology;

activating a first mode of pattern recognition alarm sensitivity to monitor the data source at a first pattern recognition level of sensitivity;

upon activating the first mode of pattern recognition alarm sensitivity also activating a second mode of pattern recognition alarm sensitivity to continue to simultaneously monitor the data source at a second level of pattern recognition sensitivity;

generating a first alarm signal upon the first mode of pattern recognition sensitivity detecting an alarm condition; and

generating a second alarm signal upon the second mode of pattern recognition sensitivity detecting an alarm condition.

2. The method as defined in claim 1 wherein the step of training includes selecting an incoming data signal comprising at least one of an on-line data signal and an archived data signal.

3. The method as defined in claim 2 wherein the on-line data signal and the archived data signal are used to calculate pattern recognition parameters.

4. The method as defined in claim 3 wherein the pattern recognition parameters comprise SPRT parameters.

5. The method as defined in claim 4 wherein the SPRT pattern recognition parameters comprise a separate group associated with each level of alarm sensitivity.

6. The method as defined in claim 1 further including the step of notifying an operator if the first alarm signal is generated.

7. The method as defined in claim 1 further including the step of responding to the first alarm signal by modifying a process associated with the data source.

8. The method as defined in claim 1 further including the step of responding to the first alarm signal by dumping historical alarm signal data for at least one of detailed study and action by a system specialist.

9. The method as defined in claim 8 wherein the detailed study comprises carrying out a diagnosis using an expert system.

10. A method of analyzing a data source, comprising the steps of:

training a system using a data signal from at least one of an on-line data signal and an archived data signal, the training including the step of using a SPRT pattern recognition methodology to determine at least two different levels of SPRT pattern recognition alarm sensitivity with each of the levels having an associated SPRT pattern recognition parameter;

activating a first mode and simultaneously a second mode of SPRT pattern recognition alarm sensitivity to continue to monitor simultaneously the data source using the at least two different levels of SPRT pattern recognition alarm sensitivity; and

generating a first alarm if the first mode of SPRT pattern recognition alarm sensitivity detects an alarm condition and generating a second alarm if the second mode of SPRT pattern recognition alarm sensitivity detects an alarm condition.

11. The method as defined in claim 10 wherein the data source is selected from the group consisting of a business data source, a chemical process, a mechanical process, an electrical process, a medical process and a manufacturing process.

12. The method as defined in claim 10 wherein the step of activating a first mode comprises performing a set of SPRT decision tests which include (a) performing a positive mean test with a signal disturbance magnitude of M₁⁺, (b) performing a negative mean test with a signal disturbance magnitude of M₁^-, (c) performing a nominal variance test with variance gain factor V₁ and (d) performing an inverse variance test with variance gain factor 1/V₁.

13. The method as defined in claim 10 wherein the step of activating a second mode comprises performing a set of SPRT decision tests which include (a) performing a positive mean test with a signal disturbance magnitude of M₂⁺, (b) performing a negative mean test with a signal disturbance magnitude of M₂^-, (c) performing a nominal variance test with variance gain factor V₂ and (d) performing an inverse variance test with variance gain factor 1/V₂.

14. The method as defined in claim 10 further including the step of accumulating historical data characteristic of an alarm condition.

15. The method as defined in claim 14 further including a method of applying an expert system to the historical data.

16. The method as defined in claim 15 wherein the method of applying an expert system includes the steps of (a) determining type of statistical test which produced the alarm condition and (b) determining which source of data generated the alarm condition.

17. The method as defined in claim 16 wherein the step of determining which source of data generated the alarm condition includes determining which sources of data are redundant and which sources of data are monitoring a same system.

18. The method as defined in claim 16 wherein the step of determining type of statistical test is followed by establishing time of alarm and calculating alarm frequencies.

19. The method as defined in claim 16 further including the step of combining alarm information and source of data information into knowledge objects.

20. The method as defined in claim 19 further including the step of processing the knowledge objects to display a diagnosis of the source of the alarm condition.