A Landsat data transformation method which was proposed by the author was applied to extract useful information from data of 769 ground feature classification units of worldwide scope.Three most important characterist...A Landsat data transformation method which was proposed by the author was applied to extract useful information from data of 769 ground feature classification units of worldwide scope.Three most important characteristic values--the general radiance level L,the visible-infrared radiation balance B and the band radiance variation vector (direction and speed) V were calculated.Then the 769 class units were sorted into 106 groups based on their natural characteristics.The means and standard deviations of L,B and V values for all the groups were calculated.The distributions of the 106 groups or the 769 units on the number axes of L,B and V,in the planes of L-B,L-V and B-V,and in the space of L-B-V were investigated.Finally,the typical numerical characteristics of the various ground features are discussed in consideration of their worldwide variations in the present paper.展开更多
Emprical mode decomposition(EMD) is a method and principle of decomposing signal dealing with Hilbert-Huang transform (HHT) in signal analysis, while directly-mean EMD is an improved EMD method presented by N.E.Huang,...Emprical mode decomposition(EMD) is a method and principle of decomposing signal dealing with Hilbert-Huang transform (HHT) in signal analysis, while directly-mean EMD is an improved EMD method presented by N.E.Huang, the inventor of HHT, which is aimed at solving the problems of EMD principle. Although the directly-mean HMD method is very remarkable with its advantages and N. E. Huang has given a method to realize it, he did not find the theoretic evidence of the method so that the feasibility of the idea and correctness of realizing the directly-mean EMD method is still indeterminate. For this a deep research on the forming process of complex signal is made and the involved stationary point principle and asymptotic stationary point principle are demonstrated, thus some theoretic evidences and the correct realizing way of directly-mean EMD method is firstly presented. Some simulation examples for demonstrating the idea presented are given.展开更多
A constitutive relation to describe pseudo-elastic deformation in shape memory alloys is pres- ented in this paper. It is capable of describing deformation behaviour of polycrystalline materials under triaxial stress ...A constitutive relation to describe pseudo-elastic deformation in shape memory alloys is pres- ented in this paper. It is capable of describing deformation behaviour of polycrystalline materials under triaxial stress state as well as of monocrystalline materials under one-dimensional condition. Total strain rate is sup- posed to be composed of elastic strain rate and transformation strain rate. Deformation behaviour of Cu-Zn-Sn alloy and Ti-Ni alloy is simulated by use of the proposed constitutive relation. It is shown that simulated results are in a good agreement with experimental data.展开更多
文摘A Landsat data transformation method which was proposed by the author was applied to extract useful information from data of 769 ground feature classification units of worldwide scope.Three most important characteristic values--the general radiance level L,the visible-infrared radiation balance B and the band radiance variation vector (direction and speed) V were calculated.Then the 769 class units were sorted into 106 groups based on their natural characteristics.The means and standard deviations of L,B and V values for all the groups were calculated.The distributions of the 106 groups or the 769 units on the number axes of L,B and V,in the planes of L-B,L-V and B-V,and in the space of L-B-V were investigated.Finally,the typical numerical characteristics of the various ground features are discussed in consideration of their worldwide variations in the present paper.
基金This project is supported by National Natural Science Foundation of China(No.50275154).
文摘Emprical mode decomposition(EMD) is a method and principle of decomposing signal dealing with Hilbert-Huang transform (HHT) in signal analysis, while directly-mean EMD is an improved EMD method presented by N.E.Huang, the inventor of HHT, which is aimed at solving the problems of EMD principle. Although the directly-mean HMD method is very remarkable with its advantages and N. E. Huang has given a method to realize it, he did not find the theoretic evidence of the method so that the feasibility of the idea and correctness of realizing the directly-mean EMD method is still indeterminate. For this a deep research on the forming process of complex signal is made and the involved stationary point principle and asymptotic stationary point principle are demonstrated, thus some theoretic evidences and the correct realizing way of directly-mean EMD method is firstly presented. Some simulation examples for demonstrating the idea presented are given.
基金The project supported by National Natural Science Foundation of China.
文摘A constitutive relation to describe pseudo-elastic deformation in shape memory alloys is pres- ented in this paper. It is capable of describing deformation behaviour of polycrystalline materials under triaxial stress state as well as of monocrystalline materials under one-dimensional condition. Total strain rate is sup- posed to be composed of elastic strain rate and transformation strain rate. Deformation behaviour of Cu-Zn-Sn alloy and Ti-Ni alloy is simulated by use of the proposed constitutive relation. It is shown that simulated results are in a good agreement with experimental data.
