Use of laser heterodyne spectrometry in determining monochromatic atmospheric transmission

1979 ◽  
Vol 9 (10) ◽  
pp. 1245-1250
Author(s):  
V I Astakhov ◽  
N V Vanin ◽  
V V Galaktionov ◽  
V M Dorokhov ◽  
V M Zakharov ◽  
...  
1973 ◽  
Vol 12 (6) ◽  
pp. 1106 ◽  
Author(s):  
S. R. King ◽  
D. T. Hodges ◽  
T. S. Hartwick ◽  
D. H. Barker

Author(s):  
S. A. Sadovnikov

Introduction: Successful monitoring of environmental parameters requires the development of flexible software complexes with evolvable calculation functionality. Purpose: Developing a modular system for numerical simulation of atmospheric laser gas analysis. Results: Based on differential absorption method, a software system has been developed which provides the calculation of molecular absorption cross-sections, molecular absorption coefficients, atmospheric transmission spectra, and lidar signals. Absorption line contours are calculated using the Voigt profile. The prior information sources are HITRAN spectroscopic databases and statistical models of the distribution of temperature, pressure and gas components in the atmosphere. For modeling lidar signals, software blocks of calculating the molecular scattering coefficient and aerosol absorption/scattering coefficients were developed. For testing the applicability of various laser sources in the problems of environmental monitoring of the atmosphere, a concentration reconstruction error calculation block was developed for the atmospheric gas components, ignoring the interfering absorption of laser radiation by foreign gases. To verify the correct functioning of the software, a program block was developed for comparing the results of the modeling of atmospheric absorption and transmission spectra by using the standard SPECTRA information system. The discrepancy between the calculation of the atmospheric transmission spectra obtained using the developed system as compared to the SPECTRA results is less than 1%. Thus, a set of the presented program blocks allows you to carry out complex modeling of remote atmospheric gas analysis. Practical relevance: The software complex allows you to rapidly assess the possibilities of using a wide range of laser radiation sources for the problems of remote gas analysis.


1983 ◽  
Author(s):  
N. Jenkins ◽  
C. Ko ◽  
T. W. Fox ◽  
R. Cammilleri ◽  
L. Caretto

2021 ◽  
Vol 13 (14) ◽  
pp. 2697
Author(s):  
Bo Liu ◽  
Qi Xiao ◽  
Yuhao Zhang ◽  
Wei Ni ◽  
Zhen Yang ◽  
...  

To address the problem of intelligent recognition of optical ship targets under low-altitude squint detection, we propose an intelligent recognition method based on simulation samples. This method comprehensively considers geometric and spectral characteristics of ship targets and ocean background and performs full link modeling combined with the squint detection atmospheric transmission model. It also generates and expands squint multi-angle imaging simulation samples of ship targets in the visible light band using the expanded sample type to perform feature analysis and modification on SqueezeNet. Shallow and deeper features are combined to improve the accuracy of feature recognition. The experimental results demonstrate that using simulation samples to expand the training set can improve the performance of the traditional k-nearest neighbors algorithm and modified SqueezeNet. For the classification of specific ship target types, a mixed-scene dataset expanded with simulation samples was used for training. The classification accuracy of the modified SqueezeNet was 91.85%. These results verify the effectiveness of the proposed method.


2011 ◽  
Vol 20 (03) ◽  
pp. 299-317
Author(s):  
E. STRAZZERI ◽  
O. CATALANO ◽  
B. SBARUFATTI

In the context of detection of Ultra High Energy Cosmic Ray (UHECR) showers from space the details of fluorescence light production and transmission in the atmosphere are given. An analytical model of the fluorescence yield, in dependence on nitrogen molecular parameters and the atmospheric conditions, is presented. Seasonal and geographical variations of the total fluorescence photon yield between 300 nm and 400 nm in air excited by 0.85 MeV electrons are shown as a function of the altitude, using different atmospheric models. In the frame of a satellite-based UHECR experiment the fluorescence yield has been corrected by the overall atmospheric transmission which takes into account, in the simplest approximation, the wavelength-dependent scattering and absorption of the fluorescence light from air molecules, from stratospheric ozone, and from aerosol. The effect of the atmospheric attenuation on the fluorescence yield is shown as a function of the altitude of the emission point of light.


1976 ◽  
Vol 15 (2) ◽  
pp. 364 ◽  
Author(s):  
Wesley A. Traub ◽  
Mark T. Stier

2021 ◽  
Vol 50 (4) ◽  
pp. 57-65
Author(s):  
黄俊 Jun HUANG ◽  
黄印博 Yinbo HUANG ◽  
卢兴吉 Xingji LU ◽  
曹振松 Zhensong CAO ◽  
齐刚 Gang QI ◽  
...  

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