By using iterative method to solve the vector radiative transfer equation of discrete scatterers with randomly rough under-boundary, the back-scattering coefficient is derived, and is applied to the two-scale model of...By using iterative method to solve the vector radiative transfer equation of discrete scatterers with randomly rough under-boundary, the back-scattering coefficient is derived, and is applied to the two-scale model of sea surface with foam scatterers driven by strong wind. By employing the modified probability density function of Cox and Munk's, and Pierson's sea spectrum, numerical results of polarized back-scatter ing are calculated. The functional dependence on wind speed and direction, observation angle, polarization and other parameters are discussed, and theoretical results are favorably matched with experimental data.展开更多
The damaged and strain subsurface layers of semi insulating(SI) GaAs substrate were characterized non destructively by Raman back scattering.The study shows that the thicknesses of the damaged and strain layers are...The damaged and strain subsurface layers of semi insulating(SI) GaAs substrate were characterized non destructively by Raman back scattering.The study shows that the thicknesses of the damaged and strain layers are less than 3μm.The damaged and strain layer can be removed after being etched in H 2SO 4·H 2O 2·H 2O for 1.5 min.展开更多
The compression of soil grain and pore fluid as well as viscid coupling of pore fluid and soil skeleton is considered, the scattering problem of incident plane P1 wave （fast compressional wave） by an infinite cylind...The compression of soil grain and pore fluid as well as viscid coupling of pore fluid and soil skeleton is considered, the scattering problem of incident plane P1 wave （fast compressional wave） by an infinite cylindrical shell deeply embedded in isotropic saturated soils is studied by adopting the amended Biot model, amplitude equations about potential functions of scattering and refracting fields are obtained, and the effect of dimensionless frequencies and shell thickness on the back-scattering spectra and dynamic stress concentration factors of two types of cylindrical shells with high and low rigidity are numerically computed and analyzed.展开更多
The effect of scattering on the transmission of subwavelength Si nanorod arrays is investigated. It is found that the distance between the nanorods has important effect on the transmission because the scattered light ...The effect of scattering on the transmission of subwavelength Si nanorod arrays is investigated. It is found that the distance between the nanorods has important effect on the transmission because the scattered light varies largely with it. When the nanorods are close to each other, the back-scattered light and the light reflected by the surface of substrates interfere destructively and lead to a high transmission. When the distance of the nanorods increases, the intensity of the scattered light decrease and this makes the transmission decrease. The reflection and the transmission of the nanorod arrays can be adjusted by changing the distance between the neighbouring nanorods.展开更多
The multi-parameter inversion of elastic wave equation in a half-space within the Born approximation is studied. A method of simultaneously reconstructing the configurations of the density and Lame parameters of the m...The multi-parameter inversion of elastic wave equation in a half-space within the Born approximation is studied. A method of simultaneously reconstructing the configurations of the density and Lame parameters of the medium was presented by use of a wideband measuring schemes in which transmitters and receivers scan over the half-space surface. It is shown that the reflected waves generated by horizontal and vertical pulses on the surface can be decomposed into P-->P, P-->S, S-->P and S-->S types of scattering components. As is expected, these components contain enough information for desired restruction. From them the density and two Lame parameters are determined explicitly, and the results obtained have the form of filtered back-propagation as in the acoustic diffraction tomography.展开更多
基金This work was supported by the National Natural Science Foundation of ChinaFok Ying Tung Education Foundation
文摘By using iterative method to solve the vector radiative transfer equation of discrete scatterers with randomly rough under-boundary, the back-scattering coefficient is derived, and is applied to the two-scale model of sea surface with foam scatterers driven by strong wind. By employing the modified probability density function of Cox and Munk's, and Pierson's sea spectrum, numerical results of polarized back-scatter ing are calculated. The functional dependence on wind speed and direction, observation angle, polarization and other parameters are discussed, and theoretical results are favorably matched with experimental data.
文摘The damaged and strain subsurface layers of semi insulating(SI) GaAs substrate were characterized non destructively by Raman back scattering.The study shows that the thicknesses of the damaged and strain layers are less than 3μm.The damaged and strain layer can be removed after being etched in H 2SO 4·H 2O 2·H 2O for 1.5 min.
文摘The compression of soil grain and pore fluid as well as viscid coupling of pore fluid and soil skeleton is considered, the scattering problem of incident plane P1 wave （fast compressional wave） by an infinite cylindrical shell deeply embedded in isotropic saturated soils is studied by adopting the amended Biot model, amplitude equations about potential functions of scattering and refracting fields are obtained, and the effect of dimensionless frequencies and shell thickness on the back-scattering spectra and dynamic stress concentration factors of two types of cylindrical shells with high and low rigidity are numerically computed and analyzed.
文摘The effect of scattering on the transmission of subwavelength Si nanorod arrays is investigated. It is found that the distance between the nanorods has important effect on the transmission because the scattered light varies largely with it. When the nanorods are close to each other, the back-scattered light and the light reflected by the surface of substrates interfere destructively and lead to a high transmission. When the distance of the nanorods increases, the intensity of the scattered light decrease and this makes the transmission decrease. The reflection and the transmission of the nanorod arrays can be adjusted by changing the distance between the neighbouring nanorods.
文摘The multi-parameter inversion of elastic wave equation in a half-space within the Born approximation is studied. A method of simultaneously reconstructing the configurations of the density and Lame parameters of the medium was presented by use of a wideband measuring schemes in which transmitters and receivers scan over the half-space surface. It is shown that the reflected waves generated by horizontal and vertical pulses on the surface can be decomposed into P-->P, P-->S, S-->P and S-->S types of scattering components. As is expected, these components contain enough information for desired restruction. From them the density and two Lame parameters are determined explicitly, and the results obtained have the form of filtered back-propagation as in the acoustic diffraction tomography.
