Airborne gravimetry has become a vital technique in local gravity field approximation, and upward/downward continuation of gravity data is a key process of airborne gravimetry. In these procedures, the integral domain...Airborne gravimetry has become a vital technique in local gravity field approximation, and upward/downward continuation of gravity data is a key process of airborne gravimetry. In these procedures, the integral domain is divided into two parts, namely the near-zone and the far-zone. The far-zone contributions are approximated by the truncation coefficients and a global geo-potential model, and their values are controlled by several issues. This paper investigates the effects of flight height, the size of near-zone cap, and Remove- Compute-Restore （RCR） technique upon far-zone contributions. Results show that at mountainous area the far-zone contributions can be ignored when EIGEN-6C of 360 degree is removed from the gravity data, together with a near-zone cap of 1°and a flight height less than 10 km, while at flat area EIGEN-6C of 180 degree is feasible.展开更多
With the help of a simple Lie algebra, an isospectral Lax pair, whose feature presents decomposition of element(1, 2) into a linear combination in the temporal Lax matrix, is introduced for which a new integrable hier...With the help of a simple Lie algebra, an isospectral Lax pair, whose feature presents decomposition of element(1, 2) into a linear combination in the temporal Lax matrix, is introduced for which a new integrable hierarchy of evolution equations is obtained, whose Hamiltonian structure is also derived from the trace identity in which contains a constant γ to be determined. In the paper, we obtain a general formula for computing the constant γ. The reduced equations of the obtained hierarchy are the generalized nonlinear heat equation containing three-potential functions,the m Kd V equation and a generalized linear Kd V equation. The algebro-geometric solutions(also called finite band solutions) of the generalized nonlinear heat equation are obtained by the use of theory on algebraic curves. Finally, two kinds of gauge transformations of the spatial isospectral problem are produced.展开更多
基金supported by the National Natural Science Foundation of China (41504013,41174062)the Open Research Fund Program of the Key Laboratory of Geospace Environment and Geodesy,Ministry of Education,China (14-01-03)the Doctoral Scientific Research Foundation of Guangdong University of Technology(253151010)
文摘Airborne gravimetry has become a vital technique in local gravity field approximation, and upward/downward continuation of gravity data is a key process of airborne gravimetry. In these procedures, the integral domain is divided into two parts, namely the near-zone and the far-zone. The far-zone contributions are approximated by the truncation coefficients and a global geo-potential model, and their values are controlled by several issues. This paper investigates the effects of flight height, the size of near-zone cap, and Remove- Compute-Restore （RCR） technique upon far-zone contributions. Results show that at mountainous area the far-zone contributions can be ignored when EIGEN-6C of 360 degree is removed from the gravity data, together with a near-zone cap of 1°and a flight height less than 10 km, while at flat area EIGEN-6C of 180 degree is feasible.
基金Supported by the Innovation Team of Jiangsu Province hosted by China University of Mining and Technology(2014)the National Natural Science Foundation of China under Grant No.11371361+1 种基金the Fundamental Research Funds for the Central Universities(2013XK03)the Natural Science Foundation of Shandong Province under Grant No.ZR2013AL016
文摘With the help of a simple Lie algebra, an isospectral Lax pair, whose feature presents decomposition of element(1, 2) into a linear combination in the temporal Lax matrix, is introduced for which a new integrable hierarchy of evolution equations is obtained, whose Hamiltonian structure is also derived from the trace identity in which contains a constant γ to be determined. In the paper, we obtain a general formula for computing the constant γ. The reduced equations of the obtained hierarchy are the generalized nonlinear heat equation containing three-potential functions,the m Kd V equation and a generalized linear Kd V equation. The algebro-geometric solutions(also called finite band solutions) of the generalized nonlinear heat equation are obtained by the use of theory on algebraic curves. Finally, two kinds of gauge transformations of the spatial isospectral problem are produced.
