The structural characteristics of 2004 typhoon Aere's precipitation are analyzed using the high-resolution data from the Tropical Rainfall Measuring Mission(TRMM) of the National Aeronautics Space Administration(N...The structural characteristics of 2004 typhoon Aere's precipitation are analyzed using the high-resolution data from the Tropical Rainfall Measuring Mission(TRMM) of the National Aeronautics Space Administration(NASA).It is found that the typhoon's characteristics vary at different stages of its development.To analyze the asymmetric causation of precipitation distribution,data from the National Center for Environmental Prediction(NCEP) reanalysis are used to calculate the vertical integral of the water vapor flux vector.The results show that because of this process,along with the unique phenomenon of twin-typhoon circulation,the easterly air current of the typhoon's northern side and the southwesterly air current of its southern side play a joint role in transporting water vapor.Furthermore,its transport effects vary greatly at the different stages of development,showing the peculiarity of the water source for this typhoon process.The distributions of the typhoon convection area—characterized by heavy precipitation and a maximum-value area of the water vapor flux,as well as a strong ascending-motion area—differ at different stages of the typhoon's development.The non-uniform distribution of water vapor flux and the vertical motion bring about asymmetrical distribution of the typhoon precipitation.展开更多
In a thin-walled, homogeneous, straight, long, circular, and incompressible fluid filled elastic tube, small but finite long wavelength nonlinear waves can be describe by a KdV (Korteweg de Vries) equation, while the ...In a thin-walled, homogeneous, straight, long, circular, and incompressible fluid filled elastic tube, small but finite long wavelength nonlinear waves can be describe by a KdV (Korteweg de Vries) equation, while the carrier wave modulations are described by a nonlinear Schr?dinger equation (NLSE). However if the elastic tube is slowly inhomogeneous, then it is found, in this paper, that the carrier wave modulations are described by an NLSE-like equation. There are soliton-like solutions for them, but the stability and instability regions for this soliton-like waves will change, depending on what kind of inhomogeneity the tube has.展开更多
Obliquely incident water wave scattering by an uneven channel-bed in the form of a small bottom undulation in a two-layer fluid is investigated within the frame work of three-dimensional linear water wave theory. The ...Obliquely incident water wave scattering by an uneven channel-bed in the form of a small bottom undulation in a two-layer fluid is investigated within the frame work of three-dimensional linear water wave theory. The upper fluid is assumed to be bounded above by a rigid lid, while the lower one is bounded below by a bottom surface having a small deformation and the channel is unbounded in the horizontal directions. Assuming irrotational motion, perturbation technique is employed to calculate the first-order corrections to the velocity potentials in the two fluids by using Fourier transform approximately, and also to calculate the reflection and transmission coefficients in terms of integrals involving the shape function representing the bottom deformation. Consideration of a patch of sinusoidal ripples shows that the reflection coefficient is an oscillatory function of the ratio of twice the component of the wave number along x-axis and the ripple wave number. When this ratio approaches one, the theory predicts a resonant interaction between the bed and interface, and the reflection coefficient becomes a multiple of the number of ripples. High reflection of incident wave energy occurs if this number is large.展开更多
The surface quality of the substrate is a crucial factor in building "clean" quantum-dimensional systems. There are a number of micro-nano metric methods for the analysis state of surface: the atomic force microsco...The surface quality of the substrate is a crucial factor in building "clean" quantum-dimensional systems. There are a number of micro-nano metric methods for the analysis state of surface: the atomic force microscopy, the scanning tunneling microscopy and others. The SE (surface electron) over substrate has a "soft" hydrogen-like spectrum in the normal direction and the SEs mobility along is sensitive to the inhomogeneities of the substrate and this is analyzed in work. The values of electron mobility and energy of thermal activation are basic parameters of transport process which essentially depend on the helium film thickness. For analysis of nano-size inhomogeneities of substrate here we apply a new method providing a uniformity of the film thickness on substrate and fixing of measuring cell with supply wires. The plunger with electro-mechanic driver into a hermetic chamber is used for variation the helium level and consequently the film thickness. Considering values the conductivity and the variation of potential along surface is estimated the effective size of roughness from several nanometers (for non-saturated helium film) to 10^2 nm (for saturated film).展开更多
基金A key project of National Foundation of Natural Science (40533015)Foundation for Meteorological Research of Jiangsu Province (K200715)a project of Foundation for Fundamental Theoretic Research of Institute of Meteorology,PLA University of Science and Technology
文摘The structural characteristics of 2004 typhoon Aere's precipitation are analyzed using the high-resolution data from the Tropical Rainfall Measuring Mission(TRMM) of the National Aeronautics Space Administration(NASA).It is found that the typhoon's characteristics vary at different stages of its development.To analyze the asymmetric causation of precipitation distribution,data from the National Center for Environmental Prediction(NCEP) reanalysis are used to calculate the vertical integral of the water vapor flux vector.The results show that because of this process,along with the unique phenomenon of twin-typhoon circulation,the easterly air current of the typhoon's northern side and the southwesterly air current of its southern side play a joint role in transporting water vapor.Furthermore,its transport effects vary greatly at the different stages of development,showing the peculiarity of the water source for this typhoon process.The distributions of the typhoon convection area—characterized by heavy precipitation and a maximum-value area of the water vapor flux,as well as a strong ascending-motion area—differ at different stages of the typhoon's development.The non-uniform distribution of water vapor flux and the vertical motion bring about asymmetrical distribution of the typhoon precipitation.
基金The project supported by National Natural Science Foundation of China under Grant No.10247008the Natural Science Foundation of Northwest Normal University under Grant No.NWNU-KJCXGC-215
文摘In a thin-walled, homogeneous, straight, long, circular, and incompressible fluid filled elastic tube, small but finite long wavelength nonlinear waves can be describe by a KdV (Korteweg de Vries) equation, while the carrier wave modulations are described by a nonlinear Schr?dinger equation (NLSE). However if the elastic tube is slowly inhomogeneous, then it is found, in this paper, that the carrier wave modulations are described by an NLSE-like equation. There are soliton-like solutions for them, but the stability and instability regions for this soliton-like waves will change, depending on what kind of inhomogeneity the tube has.
基金partially supported by a research grant from Department of Science and Technology(DST),India(No.SB/FTP/MS-003/2013)
文摘Obliquely incident water wave scattering by an uneven channel-bed in the form of a small bottom undulation in a two-layer fluid is investigated within the frame work of three-dimensional linear water wave theory. The upper fluid is assumed to be bounded above by a rigid lid, while the lower one is bounded below by a bottom surface having a small deformation and the channel is unbounded in the horizontal directions. Assuming irrotational motion, perturbation technique is employed to calculate the first-order corrections to the velocity potentials in the two fluids by using Fourier transform approximately, and also to calculate the reflection and transmission coefficients in terms of integrals involving the shape function representing the bottom deformation. Consideration of a patch of sinusoidal ripples shows that the reflection coefficient is an oscillatory function of the ratio of twice the component of the wave number along x-axis and the ripple wave number. When this ratio approaches one, the theory predicts a resonant interaction between the bed and interface, and the reflection coefficient becomes a multiple of the number of ripples. High reflection of incident wave energy occurs if this number is large.
文摘The surface quality of the substrate is a crucial factor in building "clean" quantum-dimensional systems. There are a number of micro-nano metric methods for the analysis state of surface: the atomic force microscopy, the scanning tunneling microscopy and others. The SE (surface electron) over substrate has a "soft" hydrogen-like spectrum in the normal direction and the SEs mobility along is sensitive to the inhomogeneities of the substrate and this is analyzed in work. The values of electron mobility and energy of thermal activation are basic parameters of transport process which essentially depend on the helium film thickness. For analysis of nano-size inhomogeneities of substrate here we apply a new method providing a uniformity of the film thickness on substrate and fixing of measuring cell with supply wires. The plunger with electro-mechanic driver into a hermetic chamber is used for variation the helium level and consequently the film thickness. Considering values the conductivity and the variation of potential along surface is estimated the effective size of roughness from several nanometers (for non-saturated helium film) to 10^2 nm (for saturated film).