Forecasting of the realtime data monitored by differential optical absorption spectroscopy method

Feng, Qisheng; Liu, Wenqing; Zhou, Bin; Zhen-bi, LI; Cui, Yanjun

doi:10.7498/aps.52.1307

Cited by 2 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Spline interpolation or polynomial fitting are used to obtain the differential absorption spectrum and calculate the concentration. For gas mixtures, different algorithms can be used to analyze the absorption spectrum to determine concentrations; these methods include least squares, 9 neural network, 10 and Kalman filter. 11 The algorithm for gas mixtures has some disadvantages.…”

Section: Introductionmentioning

confidence: 99%

Continuous monitoring of NO in flue gas based on wavelet decomposition

2011

View full text Add to dashboard Cite

In this paper, a new algorithm for nitric oxide (NO) measurement based on multi-scale wavelet decomposition is proposed. The algorithm uses one-dimensional discrete multi-scale wavelet decomposition to analyze the transmission spectrum of flue gas. Through the different scales of decomposition, the relation between the absorption characteristics of NO gas and the reconstruction of wavelet coefficients is found. The DB9 wavelet can obtain the most obvious absorption characteristics of the NO gas. After calibration, the algorithm is used to measure the concentration of the mixture of NO and SO(2). The results show that the algorithm is efficient towards SO(2) absorption interference with a full-scale error less than ± 0.4% in laboratory conditions. The algorithm was then applied to field measurements with an overall standard deviation of 8.37 mg m(-3), which is better than 18.92 mg m(-3) determined by the least squares method. Under the interference of desulfurization, the full-scale measurement errors are less than ± 2%. In addition, the algorithm avoids using the reference spectrum, thereby reducing the aging of the light source effectively. It has strong anti-interference capability, good durability, and practicality in the continuous monitoring of NO.

show abstract

Section: Introductionmentioning

confidence: 99%

Continuous monitoring of NO in flue gas based on wavelet decomposition

2011

View full text Add to dashboard Cite

show abstract

A convolution algorithm of differential coefficients of liquid water based on vibrational Raman scattering

Han¹,

Chen²,

Li³

et al. 2013

Acta Phys. Sin.

View full text Add to dashboard Cite

Inelastic vibrational Raman scattering by liquid water is one significant limitation to the accuracy of the retrieval of trace gas constituents in atmosphere over waters, particularly over clear ocean waters, while using satellite data with differential optical absorption spectroscopy technique (DOAS). The effect which is similar to the Ring effect in atmosphere results in the filling-in of Fraunhofer lines, which is known as solar absorption lines. The inelastic component of the liquid water scattering causes a net increase of radiance in the line because more radiations shift to the wavelength of an absorption line than from this wavelength to other wavelengths. The solar spectrum transmitting atmosphere is convolved with vibrational Raman scattering coefficient of liquid water, divided by the original computed spectrum, with a cubic polynomial subtracted off, to create differential water Ring spectrum. This method is suggested in order to obtain an effective differential water Ring coeffient for the DOAS fitting process, which could be used to improve the accuracy of the retrieval of the trace gases concentration. The method does not rely on radiative transfer model of water, which would be time-consuming and depending on lot of parameters. Therefore, it is very fast and convenient.

show abstract

Forecasting of the realtime data monitored by differential optical absorption spectroscopy method

Cited by 2 publications

References 0 publications

Continuous monitoring of NO in flue gas based on wavelet decomposition

Continuous monitoring of NO in flue gas based on wavelet decomposition

A convolution algorithm of differential coefficients of liquid water based on vibrational Raman scattering

Contact Info

Product

Resources

About