Evaluation of Inversion Algorithms on DIRSIG Generated Plume Model Simulations

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Evaluation of Inversion Algorithms on DIRSIG
Generated Plume Model Simulations

• Chia Y. Chang, John R. Schott, Scott D. Brown
• Center for Imaging Science
• Rochester Institute of Technology

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Outline

• Objective
• Significance
• Background
• Research Outline
• Method of Analysis
• Results
• Questions

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Objective

• Examine spectral signature of plumes using three
  inversion algorithms to
• Detect
• Identify
• Quantify

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Significance

• Intelligence Community
• nuclear proliferation
• EPA
• pollution monitors
• DOE
• factory efficiency

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Background

• Ph.D. Research
• S. Didi Kuo
• Code Development
• 3rd Generation Code
• Previous Work
• Cooling Tower Plumes
• Factory Stack Plumes

Hawkeye
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Research Scenario

• Chemical
• trichloroethylene (C2HCl3)
• Simple Case
• grass, concrete, asphalt
• Complex Case
• Nevada Test Site (NTS)

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Trichloroethylene (C2HCl3)

• Metal Degreaser
• 3 Dominant Peaks
• 10-13.5 micron
• Good Chemical Properties for Study

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Simple Scenes
Concrete Grass Asphalt
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Complex Scene
Smoke Stack
Smoke Stack
Reflectance Panels
Reflectance Panels
Nevada Test Site (NTS)
DIRSIGs NTS
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Complex Scene

• Trichloroethylene (C2HCl3) plume
• released over a complex scene. (11.8um)

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Original Analysis

• Spectral Signature
• 0, 5, 10, 20, 40, 50, 75 meters downwind
• Homogeneous Grass Background
• SEBASS Sensor

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Results of Preliminary Study
0 meters
5 meters
10 meters
20 meters
40 meters
50 meters
75 meters
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Old Plume

• Too Simple of a Model
• Atmospheric Stability
• Ambient Air Temperature
• No Meteorological Effects
• Wind Speed
• Wind Direction

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Meteorological File
Wind Direction Wind Velocity Ambient Air
Temperature Atmospheric Stability Stack
Temperature Stack Velocity Release Rate
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Side View

• Incorporation of meteorological file
• results in a complex plume. (11.8 um)

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Method of Analysis

• Detect
• Contrast Ratio
• Identify
• Background Subtraction
• Quantify
• Special Ratio Technique

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Contrast Ratio

Plume Radiance
Background Radiance
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Background Subtraction
Non-plume Pixel

LplumeLobserved - Lbackground
Plume Pixel
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Special Ratio Technique

Radiance Reaching a Sensor
Plume Transmission
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Volume Mixing Ratio
Absorbance

Plume Transmission
VMR
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Background Subtraction
Simple Cases
Complex Case
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Downwind Radiance Profile
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Conclusion

• Plume Characteristics
• Temperature, Chemical, Concentration
• Background Scene
• Grass, Concrete, Gravel, NTS
• Atmosphere
• Wind, Ambient Air Temperature

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QUESTIONS?