Abstract: A system for controlling the uniformity of combustion over a range of operating conditions in a combustor with a plurality of fuel nozzles. The system includes a number of optical sensors, each sensor comprising an optical probe that collects naturally occurring optical radiation emanating from a segment of the combustor or combustor exhaust, and at least one transducer that receives the radiation collected by the probes, compares the intensity of collected radiation from each sensor in a plurality of spectral pass-bands that are indicative of the fuel/air ratio in the combustor segments, and produces output signals that are indicative of the state of combustion in the combustor segments. A control system receives the output signals from the transducers and in response controls the fuel flow to the fuel nozzles to achieve an output from each of the sensors that has been determined to be indicative of a predetermined state of combustion.

Abstract: A method of automatically determining a measure of atmospheric aerosol optical properties using a multi- or hyper-spectral, multi-pixel image. A plurality of spectrally-diverse pixels are resolved from the image. A statistical spectral deviation of the spectrally-diverse pixels is determined, and then corrected for non-aerosol transmittance losses. One or more wavelength-dependent aerosol optical depths are derived from the statistical spectral deviation. Wavelength-dependent gaseous optical depths can be derived from the statistical spectral deviation.

Abstract: A method of automatically compensating a multi- or hyper-spectral, multi-pixel image for atmospheric effects, comprising resolving a plurality of spectrally-diverse pixels from the image, determining a spectral baseline from the spectrally-diverse pixels, determining a statistical spectral deviation of the spectrally-diverse pixels, normalizing the statistical spectral deviation by applying a scale factor, and compensating image pixels with both the spectral baseline and the normalized spectral deviation.

Abstract: A method of automatically compensating a multi- or hyper-spectral, multi-pixel image for atmospheric effects, comprising resolving a plurality of spectrally-diverse pixels from the image, determining a spectral baseline from the spectrally-diverse pixels, determining a statistical spectral deviation of the spectrally-diverse pixels, normalizing the statistical spectral deviation by applying a scale factor, and compensating image pixels with both the spectral baseline and the normalized spectral deviation.