On the assumption that seismic source is simplified as linear rupture fault with finite length, this paper qualitatively studies the seismic source effects on space correlation of strong ground motion. Based on expand...On the assumption that seismic source is simplified as linear rupture fault with finite length, this paper qualitatively studies the seismic source effects on space correlation of strong ground motion. Based on expanding expression of Fourier spectrum of strong ground motion with space coordinate variables, this paper also gives a expression of describing correlation of strong ground motion field. According to far-field condition, the theoretical formula of the expression can be obtained. Furthermore, this paper presents a theoretical formula of estimation the radius of strong ground motion field, which depends on expansion condition of Fourier spectrum of strong ground motion, with space variables. At last, taking one earthquake as an example, this paper gives three-dimension patterns of radius of the field with epicenter distance and azimuth as well as frequency.展开更多
Half-space Green's function due to a spatially harmonic line load has been expressed as a sum of the full-space Green's functions and a 2-D integral representation of the reflected waves by the free surface of...Half-space Green's function due to a spatially harmonic line load has been expressed as a sum of the full-space Green's functions and a 2-D integral representation of the reflected waves by the free surface of the half-space.By using the obtained half-space Green's function,an integral rep- resentation of the scattered waves by a cylindrical obstacle is then derived.Finally,by analyzing the far-zone behavior of the integrands of the integral representation.the far-field pattern of the scattered waves in a half-space obtained.展开更多
The motion planning problem of a free flying space robot (FFSR) is investigated and from the attitude disturbance characteristics of a multi arm FFSR, a new method based on the fixed attitude restricted (FAR) Gene...The motion planning problem of a free flying space robot (FFSR) is investigated and from the attitude disturbance characteristics of a multi arm FFSR, a new method based on the fixed attitude restricted (FAR) Generalized Jacobian Matrix of a multi arm FFSR is proposed to enable the coordinated motion of all the other arms while one arm is tracing a given path so that there is no disturbance on the body, and the problem of attitude disturbance with an operating multi arm FFSR is thereby better resolved. The simulation run with a dual arm FFSR system verifies the effectiveness of this algorithm.展开更多
文摘On the assumption that seismic source is simplified as linear rupture fault with finite length, this paper qualitatively studies the seismic source effects on space correlation of strong ground motion. Based on expanding expression of Fourier spectrum of strong ground motion with space coordinate variables, this paper also gives a expression of describing correlation of strong ground motion field. According to far-field condition, the theoretical formula of the expression can be obtained. Furthermore, this paper presents a theoretical formula of estimation the radius of strong ground motion field, which depends on expansion condition of Fourier spectrum of strong ground motion, with space variables. At last, taking one earthquake as an example, this paper gives three-dimension patterns of radius of the field with epicenter distance and azimuth as well as frequency.
文摘Half-space Green's function due to a spatially harmonic line load has been expressed as a sum of the full-space Green's functions and a 2-D integral representation of the reflected waves by the free surface of the half-space.By using the obtained half-space Green's function,an integral rep- resentation of the scattered waves by a cylindrical obstacle is then derived.Finally,by analyzing the far-zone behavior of the integrands of the integral representation.the far-field pattern of the scattered waves in a half-space obtained.
文摘The motion planning problem of a free flying space robot (FFSR) is investigated and from the attitude disturbance characteristics of a multi arm FFSR, a new method based on the fixed attitude restricted (FAR) Generalized Jacobian Matrix of a multi arm FFSR is proposed to enable the coordinated motion of all the other arms while one arm is tracing a given path so that there is no disturbance on the body, and the problem of attitude disturbance with an operating multi arm FFSR is thereby better resolved. The simulation run with a dual arm FFSR system verifies the effectiveness of this algorithm.