Probabilistic neural network for multi-criteria fire detector

• US 20060006997A1
• Filed: 09/01/2005
• Published: 01/12/2006
• Est. Priority Date: 06/16/2000
• Status: Active Grant

• Current Assignee: Navy The USA As Represented By The Secretary of The
• Original Assignee: US Government In The Name of The Secretary of Navy
• Inventors: Hammond, Mark H., Rose-Pehrsson, Susan, Gottuk, Daniel T., Schaffer, Ronald E., Hart, Sean J.
• Granted Patent: US 7,170,418 B2
• Time in Patent Office: Days
• US Class Current: 340/522
• CPC Class Codes: G08B 17/00 Fire alarms; Alarms responsive to explosion
• CPC Class Codes: G08B 29/183 Single detectors using dual technologies G08B13/1672, G08B13/2448, G08B13/2494 take precedence
• CPC Class Codes: G08B 31/00 Predictive alarm systems characterised by extrapolation or other computation using updated historic data

Abstract

A multi-criteria event detection system, comprising a plurality of sensors, wherein each sensor is capable of detecting a signature characteristic of a presence of an event and providing an output indicating the same. A processor for receiving each output of the plurality of sensors is also employed. The processor includes a probabilistic neural network for processing the sensor outputs. The probabilistic neural network comprises a nonlinear, nor-parametric pattern recognition algorithm that operates by defining a probability density function for a plurality of data sets that are each based on a training set data and an optimized kernel width parameter. The plurality of data sets includes a baseline, non-event, first data set; a second, event data set; and a third, nuisance data set. The algorithm provides a decisional output indicative of the presence of a fire based on recognizing and discrimination between said data sets, and whether the outputs suffice to substantially indicate the presence of an event, as opposed to a non-event or nuisance situation.

Claims

1. A multi-criteria event detection system comprising:

a plurality of sensors, wherein each said sensor is capable of detecting a signature characteristic of a presence of an event and providing an output indicating the same;

a processor for receiving each of said outputs of said plurality of sensors, said processor including a probabilistic neural network for processing said outputs, and wherein said probabilistic neural network comprises a nonlinear, non-parametric pattern recognition algorithm that operates by defining a probability density function for a plurality of data sets that are each based on a training set data and an optimized kernel width parameter, and wherein said plurality of data sets includes;

a baseline, non-event, first data set;

a second, event data set; and

a third, nuisance data set;

wherein said algorithm provides a decisional output indicative of the presence of the event based on recognizing and discriminating between said data sets and whether said outputs suffice to substantially indicate the presence of the event as opposed to the non-event or a nuisance situation.

2. A system as in claim 1, wherein said algorithm comprises just one such optimized kernel width parameter that along with on of said training set data defines said probability density function for each said data set.

3. A system as in claim 2, wherein said algorithm further comprises a cross-validation protocol for determining said optimized kernel width parameter.

4. A system as in claim 1, wherein said sensors are environmental sensors.

5. A system as in claim 1, wherein said sensors include at least one of temperature sensors, oxygen sensors, photoelectric smoke detectors, ionization smoke detectors, residual ionization smoke detectors, optical density meters, relative humidity sensors, nitric oxide detectors, nitrogen dioxide sensors, hydrogen cyanide sensors, hydrogen chloride sensors, hydrogen sulfide sensors, sulphur dioxide sensors, carbon monoxide sensors, carbon dioxide sensors, ethylene sensors, hydrogen sensors, and measuring ionization chambers.

6. A system as in claim 1, wherein said event is hazardous to persons or property, and said non-event is not hazardous to persons or property.

7. A method for detecting the presence of an event, comprising:

establishing a plurality of data sets, said data sets including;

a baseline, non-event, first data set;

a second, event data set; and

a third nuisance data set;

training each of said data sets to respond to an input and provide a representative output;

sensing a plurality of signatures;

encoding each of said plurality of signatures in a numerical output representative of a point or location in a multidimensional space;

inputting each said numerical output to a probabilistic neural network, said network defining a probability density function for each said data set based on said training set data and an optimized kernel width parameter; and

correlating said numerical outputs to a location in said multidimensional space to determine the presence or absence of the event at said location.

8. A method as in claim 7, wherein only one said optimized kernel width parameter and one of said training set data defines said probability density function for each said data set.

9. A method as in claim 7, further comprising:

determining said optimized kernel width parameter through cross-validation.

10. A method as in claim 7, wherein said sensing includes sensing at least one of temperature, oxygen, smoke, optical density meters, relative humidity, nitric oxide, nitrogen dioxide, hydrogen cyanide, hydrogen chloride, hydrogen sulfide, sensors, carbon monoxide, carbon dioxide, ethylene, hydrogen, and ionization.

11. A method as in claim 7, wherein said event is hazardous to persons or property, and said non-event is not hazardous to persons or property.