METHODS AND SYSTEMS FOR STATISTICAL BASED MONITORING AND POWER MANAGEMENT

• US 20080077355A1
• Filed: 09/21/2006
• Published: 03/27/2008
• Est. Priority Date: 09/21/2006
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Casler, David C., De Groen, Piet C., Mitchell, Joan L.
• Granted Patent: US 7,343,267 B1
• Time in Patent Office: Days
• US Class Current: 702/179
• CPC Class Codes: G06Q 10/10 Office automation; Time management
• CPC Class Codes: G06Q 50/26 Government or public services business processes related to the transportation industry G06Q50/40

Abstract

Embodiments of the present invention provide devices and techniques for detecting anomalies in monitored environments. In one embodiment of the invention, data may be acquired by monitoring an environmental variable. Based on the acquired data, statistics may be calculated which model the behavior of the environmental variable. Based on the calculated statistics, a long-term behavior and a short-term behavior of the statistics may also be calculated. A difference between the long-term statistics and the short-term statistics may then be calculated. If the difference between the long-term statistical behavior and short-term statistical behavior exceeds a dynamic or predefined threshold, an action may be taken.

Claims

1. A computer-implemented method of detecting an anomaly in a signal, comprising:

calculating a first plurality of values based on a set of statistics which model the signal, wherein the first plurality of values is calculated over a first period of time;

calculating a second plurality of values based on the set of statistics which model the signal, wherein the second plurality of values is calculated over a second period of time;

calculating a third plurality of values, wherein the third plurality of values is calculated using the first plurality of values and the second plurality of values, and wherein the third plurality of values is calculated based on a least an autocorrelation of the signal;

calculating a difference between at least one of the third plurality of values and a corresponding long-term value, wherein the long-term value is calculated over a third period of time, and wherein the third period of time is greater than the first and second periods of time;

comparing the difference to a threshold wherein the difference exceeding the threshold is indicative of the anomaly in the signal;

if the difference exceeds the threshold, performing an action wherein performing the action requires a relative increase in power consumption; and

transmitting an alert signal or a portion of the signal indicating when the difference exceeds the threshold.

2. The computer-implemented method of claim 1, wherein the second period of time can begin later or differ in duration as compared to the first period of time.

3. The computer-implemented method of claim 1, further comprising, calculating the threshold based on the set of statistics which model the signal.

4. The computer-implemented method of claim 1, wherein the action comprises sending an alert to a base unit or at least a portion of the signal to the base unit.

5. The computer-implemented method of claim 4, wherein the portion of the signal sent to the remote device contains an anomaly.

6. The computer-implemented method of claim 1, wherein the threshold is predefined.

7. The computer-implemented method of claim 1, further comprising calculating the set of statistics which models by calculating at least one of a mean of the signal, a variance of the signal, or an variance of the autocorrelation of the signal.

8. The computer-implemented method of claim 7, wherein:

calculating the first plurality of values comprises calculating at least one of an average of the mean of the signal over the first period of time, an average of the variance of the signal over the first period of time, a variance of the mean of the signal over the first period of time, and a variance of the variance of the signal over the first period of time;

calculating the second plurality of values comprises calculating at least one of an average of the mean of the signal over the second period of time, an average of the variance of the signal over the second period of time, a variance of the mean of the signal over the second period of time, and a variance of the variance of the signal over the second period of time; and

calculating the third plurality of values comprises calculating at least one of an average of the variance of the autocorrelation of the signal over the first and second periods of time or a variance of the variance of the autocorrelation of the signal over the first and second periods of time.

9. A computer readable storage medium containing a program for detecting an anomaly in a signal which, when executed, performs an operation, comprising:

calculating a first plurality of values based on a set of statistics which model the signal, wherein the first plurality of values is calculated over a first period of time;

calculating a second plurality of values based on the set of statistics which model the signal, wherein the second plurality of values is calculated over a second period of time;

calculating a third plurality of values, wherein the third plurality of values is calculated using the first set of values and the second set of values and wherein the third plurality of values is calculated based on at least an autocorrelation of the signal;

calculating a difference between at least one of the third plurality of values and a corresponding long-term value, wherein the long-term value is calculated over a third period of time, and wherein the third period of time is greater than the first and second periods of time;

comparing the difference to a threshold wherein the difference exceeding the threshold is indicative of the anomaly in the signal;

if the difference or exceeds the threshold, performing an action wherein performing the action requires a relative increase in power consumption; and

transmitting an alert signal or a portion of the signal indicating when the difference exceeds the threshold.

10. The computer readable storage medium of claim 9, wherein the second period of time can begin later or differ in duration as compared the first period of time.

11. The computer readable storage medium of claim 9, wherein the operations further comprise, calculating the threshold based on the set of statistics which model the signal.

12. The computer readable storage medium of claim 9, wherein the action comprises at least one of sending an alert to a base unit or at least a portion of the signal to the base unit.

13. The computer readable storage medium of claim 9, further comprising calculating the set of statistics which models by calculating at least one of a mean of the signal, a variance of the signal, or a variance of the autocorrelation of the signal;

and

wherein calculating the first plurality of values comprises calculating at least one of an average of the mean of the signal over the first period of time, an average of the variance of the signal over the first period of time, a variance of the mean of the signal over the first period of time, and a variance of the variance of the signal over the first period of time;

calculating the second plurality of values comprises calculating at least one of an average of the mean of the signal over the second period of time, an average of the variance of the signal over the second period of time, a variance of the mean of the signal over the second period of time, and a variance of the variance of the signal over the second period of time; and

calculating the third plurality of values comprises calculating at least one of an average of the variance of the autocorrelation of the signal over the first and second periods of time or a variance of the variance of the autocorrelation of the signal over the first and second periods of time.

14. An apparatus for detecting an anomaly in a signal, comprising:

a sensor; and

a signal processing unit coupled with the sensor, wherein the signal processing unit performs operations comprising;

calculating a first plurality of values based on a set of statistics which model the signal, wherein the first plurality of values is calculated over a first period of time;

calculating a second plurality of values based on the set of statistics which model the signal, wherein the second plurality of values is calculated over a second period of time;

calculating a third plurality of values, wherein the third plurality of values is calculated using first plurality of values and the second plurality of values and wherein the third plurality of values is calculated based on at least an autocorrelation of the signal;

calculating a difference between at least one of the third plurality of values and a corresponding long-term value, wherein the long-term value is calculated over a third period of time, and wherein the third period of time is greater than the first and second periods of time;

comparing the difference to a threshold, wherein the difference exceeding the threshold is indicative of the anomaly in the signal;

if the difference exceeds the threshold, performing an action wherein performing the action requires an increase in power consumption; and

transmitting an alert signal or a portion of the signal indicating when the difference exceeds the threshold.

15. The apparatus of claim 14, further comprising a storage device coupled to the signal processing unit, wherein at least a portion of the signal is stored by the signal processing unit in the storage device.

16. The apparatus of claim 14, wherein the system further comprises a signal transmission device coupled with the signal processing unit, and wherein the action comprises transmitting data.

17. The apparatus of claim 16, wherein data comprises at least one of an alert or a portion of the signal.

18. The apparatus of claim 14, wherein the operations further comprise, calculating the threshold based on the set of statistics which model the signal.

19. The apparatus of claim 14, further comprising calculating the set of statistics which models by calculating at least one of a mean of the signal, a variance of the signal, or a variance of the autocorrelation of the signal.

20. The apparatus of claim 19, wherein:

the operation of calculating the first plurality of values comprises calculating at least one of an average of the mean of the signal over the first period of time, an average of the variance of the signal over the first period of time, a variance of the mean of the signal over the first period of time, and a variance of the variance of the signal over the first period of time;

the operation of calculating the second plurality of values comprises calculating at least one of an average of the mean of the signal over the second period of time, an average of the variance of the signal over the second period of time, a variance of the mean of the signal over the second period of time, and a variance of the variance of the signal over the second period of time; and

the operation of calculating the third plurality of values comprises calculating at least one of an average of the variance of the autocorrelation of the signal over the firs and second periods of time or a variance of the variance of the autocorrelation of the signal over the first and second periods of time.