Simulation and Calculation of 10.6μm Laser Time Broadening and Space Broadening Characteristics in Near-Earth Dust

2013 ◽  
Vol 401-403 ◽  
pp. 437-440 ◽  
Author(s):  
Ni Chen Yang ◽  
Hong Xia Wang ◽  
You Zhang Zhu
Keyword(s):  
Monte Carlo ◽  
Time Delay ◽  
Size Distribution ◽  
Scattering Theory ◽  
Mie Scattering ◽  
Dust Particles ◽  
Distribution Model ◽  
Laser Scattering ◽  
Transmission Distance ◽  
Mie Scattering Theory

Based on the Mie scattering theory and the gamma size distribution model, 10.6μm laser scattering characteristics in dust particles are calculated and analyzed.On this basis,the time broadening and space broadening characteristics of the laser are analyzed by using Monte Carlo method.Transmittance change with the transmission distance are quantitative calculated and the time detention and space broadening characteristics of the laser passed through dust for different transmission distances are calculated and analyzed. The results show that the transmittance decreases with increasing transmission distance, and the transmittance is close to 0 when transmission distance is close to 200m; The time delay of 10.6μm laser is more significant with the increaseing transmission distance; The space broadening of 10.6μm laser is more obvious and the energy is more dispersed with the increaseing transmission distance.

scholarly journals Prediction of Aerosol Particle Size Distribution Based on Neural Network

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Yali Ren ◽  
Jiandong Mao ◽  
Hu Zhao ◽  
Chunyan Zhou ◽  
Xin Gong ◽  
...  
Keyword(s):  
Neural Network ◽  
Integral Equation ◽  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Bp Neural Network ◽  
Scattering Theory ◽  
Mie Scattering ◽  
Aerosol Particle Size ◽  
Mie Scattering Theory

Aerosol plays a very important role in affecting the earth-atmosphere radiation budget, and particle size distribution is an important aerosol property parameter. Therefore, it is necessary to determine the particle size distribution. However, the particle size distribution determined by the particle extinction efficiency factor according to the Mie scattering theory is an ill-conditioned integral equation, namely, the Fredholm integral equation of the first kind, which is very difficult to solve. To avoid solving such an integral equation, the BP neural network prediction model was established. In the model, the aerosol optical depth obtained by sun photometer CE-318 and kernel functions obtained by Mie scattering theory were used as the inputs of the neural network, particle size distributions collected by the aerodynamic particle sizer APS 3321 were used as the output, and the Levenberg–Marquardt algorithm with the fastest descending speed was adopted to train the model. For verifying the feasibility of the prediction model, some experiments were carried out. The results show that BP neural network has a better prediction effect than that of the RBF neural network and is an effective method to obtain the aerosol particle size distribution of the whole atmosphere column using the data of CE-318 and APS 3321.

Study of Oceanic Suspended Particles Density Detecting Technology Based on Mie Scattering Theory

2012 ◽  
Vol 192 ◽  
pp. 425-429
Author(s):  
Hong Lin ◽  
Xin Min Wang ◽  
Chuan Lin Zhou ◽  
Wei Zhong Li
Keyword(s):  
Scattering Theory ◽  
New Technology ◽  
Suspended Particles ◽  
Mie Scattering ◽  
Airborne Lidar ◽  
Optical Scattering ◽  
Laser Scattering ◽  
Scattering Ratio ◽  
Mie Scattering Theory ◽  
Scattering Signal

A new technology about ocean suspended particles density detecting by Mie scattering theory is proposed. This technology is based on analyzing and studying the transmission characteristics of the laser in the seawater. Based on Mie scattering theory, the optical scattering characteristics of oceanic suspended particles is researched, and a new method of calculating the scattering coefficient and backward scattering ratio is putted forward. By detecting the laser scattering signal under the seawater, the density information of ocean suspended particles can be gain and detect. A ocean suspended particles density detecting model based on airborne lidar system is firstly established through analyzing the absorbing and scattering characteristics of the suspended particles. By simulating and calculating, it is proved that the technology can detect and monitor the density of ocean suspended particles effectively, and therefore it can predict the density change of ocean suspended particles also.

scholarly journals Predicted Light Scattering from Particles Observed in Human Age-Related Nuclear Cataracts Using Mie Scattering Theory

2007 ◽  
Vol 48 (1) ◽  
pp. 303 ◽  
Author(s):  
M. Joseph Costello ◽  
So¨nke Johnsen ◽  
Kurt O. Gilliland ◽  
Christopher D. Freel ◽  
W. Craig Fowler
Keyword(s):  
Light Scattering ◽  
Scattering Theory ◽  
Mie Scattering ◽  
Age Related ◽  
Mie Scattering Theory

Model Calculations of the F-Corona and inner Zodiacal Light

2020 ◽  
Author(s):  
Saliha Eren ◽  
Ingrid Mann
Keyword(s):  
Size Distribution ◽  
White Light ◽  
Scattered Light ◽  
Mie Scattering ◽  
Dust Particles ◽  
Line Of Sight ◽  
The Sun ◽  
Zodiacal Light ◽  
Model Calculations ◽  
Zodiacal Dust

<p>The white-light Fraunhofer corona (F-corona) and inner Zodiacal light are generated by interplanetary (Zodiacal) dust particles that are located between Sun and observer. At visible wavelength the brightness comes from sunlight scattered at the dust particles. F-corona and inner Zodiacal light were recently observed from STEREO (Stenborg et al. 2018) and Parker Solar Probe (Howard et al. 2019) spacecraft which motivates our model calculations. We investigate the brightness by integration of scattered light along the line of sight of observations. We include a three-dimensional distribution of the Zodiacal dust that describes well the brightness of the Zodiacal light at larger elongations, a dust size distribution derived from observations at 1AU and assume Mie scattering at silicate particles to describe the scattered light over a large size distribution from 1 nm to 100 µm. From our simulations, we calculate the flattening index of the F-corona, which is the ratio of the minor axis to the major axis found for isophotes at different distances from the Sun, respectively elongations of the line of sight. Our results agree well with results from STEREO/SECCHI observational data where the flattening index varies from 0.45° and 0.65° at elongations between 5° and 24°. To compare with Parker Solar Probe observations, we investigate how the brightness changes when the observer moves closer to the Sun. This brightness change is influenced by the dust number density along the line of sight and by the changing scattering geometry.</p><p>-Stenborg G., Howard R. A., and Stauffer J. R., 2018: Characterization of the White-light Brightness of the F-corona between 5° and 24° Elongation, Astrophys. J. 862: 168 (21pp).</p><p>-Howard, R.A. and 25 co-authors, 2019: Near-Sun observations of an F-corona decrease and K-corona fine structure, Nature 576, 232–236.</p>

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