Leveraging air/water current variability for sensor network verification and source localization

• US 9,766,220 B2
• Filed: 02/08/2016
• Issued: 09/19/2017
• Est. Priority Date: 02/08/2016
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Chang, Josephine B., Hamann, Hendrik F., Lu, Siyuan, Muralidhar, Ramachandran, Van Kessel, Theodore G.
• Primary Examiner(s): BETSCH, REGIS J
• Application Number:
  US15/017,943
• Publication Number:
  US 20170227509A1
• Time in Patent Office: 589 Days
• CPC Class Codes: G01N 33/0031 comprising two or more sensors, e.g. a sensor array
• CPC Class Codes: G01N 33/0036 specially adapted to detect a particular component physical analysis of gaseous biological material G01N33/497
• CPC Class Codes: G01N 33/0062 concerning the measuring method or the display, e.g. intermittent measurement or digital display
• CPC Class Codes: G01N 33/007 Arrangements to check the analyser calibrating gas analysers G01N33/0006
• CPC Class Codes: G01N 33/0075 for multiple spatially distributed sensors, e.g. for environmental monitoring
• CPC Class Codes: G01N 33/18 Water
• CPC Class Codes: G01P 5/00 Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft application of speed-measuring devices for measuring volume of fluid G01F

Abstract

A method for measuring pollution that includes providing a plurality of analyte sensors arranged in a grid over a sensing area, wherein the analyte sensors measure a pollutant, and positioning at least one current sensor in the sensing area. A pollution source is localized using a pollution source locator including a dispersion model and at least one hardware processor to interpolate a location of a pollution source from variations in current measured from the current sensors and measurements of pollutants from the analyte sensors.

Claims

1. A method for measuring pollution comprising:

providing a plurality of analyte sensors arranged in a grid over a sensing area, wherein the analyte sensors measure a pollutant relative to a background analyte reading;

positioning at least one current sensor in the sensing area for measuring wind current, water current or a combination thereof, wherein changes in current are measured with the current sensor;

validating operation of at least one of said analyte sensors in said grid with said at least one current sensor, wherein when said current sensor measures a current rate above a background current rate said at least one of said analyte sensors in said corresponding to said current sensor measuring said current rate above the background current can not sense accurate pollutant measurements; and

localizing a pollution source using a pollution source locator including a dispersion model and at least one hardware processor to interpolate a location of a pollution source from variations in current measured from the current sensors and measurements of pollutants from the analyte sensors from sites on the grid that are above the background analyte reading.

2. The method of claim 1, wherein said pollution comprises air pollution, water pollution or a combination thereof.

3. The method of claim 1, further comprising validating analyte sensor operation when said at least one current sensor measures a current rate.

4. The method of claim 3, wherein said validating analyte sensor operation comprises monitoring whether analyte sensors are operating at a uniform background reading.

5. The method of claim 4, wherein if said analyte sensors are operating at a uniform background reading said analyte sensors have been validated, and wherein if said analyte sensors are not operating at a uniform background reading said analyte sensors need calibration.

6. The method of claim 1, wherein said localizing the pollution source using the pollution source locator comprises:

monitoring said current sensors for changes in current speed, current direction or a combination thereof for at least two current changing events;

measuring pollutants from said plurality of said analyte sensors for each of said at least two current changing events; and

inputting data from at least one of said pollutants measured by said plurality of said analyte sensors, location of said analyte sensors reading said pollutants, and said current speed, said current direction or said combination thereof by said current sensors into said dispersion model to said interpolate said location of said pollution source.

7. The method of claim 6, wherein said dispersion model comprises:

8. The method of claim 1, wherein said pollutant is an air pollutant selected from the group consisting of sulfur oxide (SO_x), sulfur dioxide (SO₂), nitrogen oxide (NO_x), nitrogen dioxide (NO₂), sulfuric acid (H₂SO₄), carbon monoxide (CO), carbon dioxide (CO₂), volatile organic compounds (VOCs), methane (CH₄), non-methane volatile organic compounds (NMVOCs), particulate matter (PM), atmospheric particulate matter, fine particles, persistent free radicals, toxic metals, mercury, lead, chlorofluorocarbons, ammonia, natural gas, propane, smog (black carbon) and combinations thereof.

9. The method of claim 1, wherein said analyte sensor comprises an active element selected from the group consisting of an electrochemical cell, a metal oxide semiconductor, UV adsorption active element, light scattering sensor element, and combinations thereof.

10. A system for determining the source of a pollutant comprising:

a receiver for receiving measurements of current variations from a current sensor positioned in a sensing area for measuring wind current, water current or a combination thereof, and for receiving pollutant measurements from a plurality of analyte sensors positioned on a grid of the sensing area;

a sensor validator that determines using current measurements form the current sensor whether the analyst sensors are functioning, wherein said sensor validator validates analyte sensor operation when said current sensor measures a current rate above a background current rate so that the analyte sensor can not sense pollutant measurements, wherein said validating analyte sensor operation includes monitoring whether said analyte sensors are operating at a uniform background reading; and

a pollution source locator including a dispersion model and at least one hardware processor to interpolate a location of a pollution source from variations in current measured from the current sensors and measurements of pollutants from the analyte sensors from sites on the grid that are above a background reading.

11. The system of claim 10, wherein said pollution comprises air pollution, water pollution or a combination thereof.

12. The system of claim 10, wherein said sensor validator validates analyte sensor operation when said current sensor measures a current rate above a background current rate, wherein said validating analyte sensor operation includes monitoring whether said analyte sensors are operating at a uniform background reading.

13. The system of claim 12, wherein if said analyte sensors are operating at a uniform background reading said analyte sensors have been validated, and wherein if said analyte sensors are not operating at a uniform background reading said analyte sensors need calibration.

14. The system of claim 12, wherein said pollution source locator monitors said current sensors for changes in current speed, current direction or a combination thereof for at least two current changing events to determine when to monitor readings from said analyte sensors when determining said location of said pollution source.

15. The system of claim 14, wherein in response to a change in at least one of the current speed and the current direction, the pollution source locator inputs data from the pollutants measured by the plurality of the analyte sensors, location of the analyte sensors reading said pollutants, and the current speed, the current direction or combination thereof by said current sensors into the dispersion model to said interpolate the location of the pollution source.

16. The system of claim 15, wherein said dispersion model comprises:

17. The system of claim 10, wherein said pollutant is an air pollutant selected from the group consisting of sulfur oxide (SO_x), sulfur dioxide (SO₂), nitrogen oxide (NO_x), nitrogen dioxide (NO₂), sulfuric acid (H₂SO₄), carbon monoxide (CO), carbon dioxide (CO₂), volatile organic compounds (VOCs), methane (CH₄), non-methane volatile organic compounds (NMVOCs), particulate matter (PM), atmospheric particulate matter, fine particles, persistent free radicals, toxic metals, mercury, lead, chlorofluorocarbons, ammonia, natural gas, propane, smog (black carbon) and combinations thereof.

18. The system of claim 10, wherein said analyte sensor comprises an active element selected from the group consisting of an electrochemical cell, a metal oxide semiconductor, UV adsorption active element, light scattering sensor element, and combinations thereof.

19. A non-transitory computer readable storage medium is provided that includes a computer readable program for determining a source of air pollution, the computer readable program when executed on a computer causes the computer to perform the steps of:

receiving measurements of current variations from a current sensor positioned in a sensing area for measuring wind current, water current or a combination thereof;

receiving pollutant measurements from a plurality of analyst sensors positioned on a grid of the sensing area;

determining at current values above a background current value that do not allow for accurate measurement of pollutants by the analyte sensors, the current values above said background current value received from the current sensors whether the analyte sensors are calibrated, wherein calibrated analyte sensors read a uniform background reading at said current values above said background current value; and

localizing a pollution source with a pollution source locator including a dispersion model and at least one hardware processor to interpolate a location of a pollution source from variations in current measured from the current sensors and measurements of pollutants from the analyte sensors from sites on the grid.

20. The non-transitory computer readable storage medium of claim 19, wherein said pollution comprises air pollution, water pollution or a combination thereof.