The deep structure features around Tancheng M8 /2 earthquake occurred in 1668 have been analyzed. Based on the crustal velocity structure obtained from travel-time tomographic inversion, especially the low velocity zo...The deep structure features around Tancheng M8 /2 earthquake occurred in 1668 have been analyzed. Based on the crustal velocity structure obtained from travel-time tomographic inversion, especially the low velocity zones in middle crust and Moho depths, the deep velocity structure distribution in the area of 34° ~ 36°N, 118° ~ 119°E is scanned along the latitude, longitude and oblique directions, and the corresponding crustal velocity profiles are obtained. By comparison, we take the area with velocity features coincident to the deep structure of the 1668 Tancheng M8/2 earthquake as the deduced epicenter, which is at 34. 8° ~35. 2°N, 118. 2° ~ 118. 7°E, and the reasonable location is 35. isN, 118. 6°E, and the focal depth is 20km.展开更多
Sensitivities of eigen-solutions to control variables play an important role in microgrid studies,such as coordinated optimal design of controllers and parameters,robust stability analysis on control variables,oscilla...Sensitivities of eigen-solutions to control variables play an important role in microgrid studies,such as coordinated optimal design of controllers and parameters,robust stability analysis on control variables,oscillation modes analysis on a system,etc.Considering the importance of sensitivities and the complexity of state matrix in a microgrid,parameter perturbations are utilized in this paper to analyze the construction characteristics of state matrix.Then,the sensitivities of eigenvalues and eigenvectors to control variables are obtained based on the first-order matrix perturbation theory,which makes the complex derivations of sensitivity formulas and repeated solutions of eigenvalue problem unnecessary.Finally,the effectiveness of the matrix perturbation based approach for sensitivity calculation in a microgrid is verified by a numerical example on a low-voltage microgrid prototype.展开更多
基金funded jointly by the National Natural Science Foundation of China(Grant No.40974031)Science and Technology Development Program of Jiangsu Province(BE2009691)
文摘The deep structure features around Tancheng M8 /2 earthquake occurred in 1668 have been analyzed. Based on the crustal velocity structure obtained from travel-time tomographic inversion, especially the low velocity zones in middle crust and Moho depths, the deep velocity structure distribution in the area of 34° ~ 36°N, 118° ~ 119°E is scanned along the latitude, longitude and oblique directions, and the corresponding crustal velocity profiles are obtained. By comparison, we take the area with velocity features coincident to the deep structure of the 1668 Tancheng M8/2 earthquake as the deduced epicenter, which is at 34. 8° ~35. 2°N, 118. 2° ~ 118. 7°E, and the reasonable location is 35. isN, 118. 6°E, and the focal depth is 20km.
基金supported by the National Natural Science Foundation of China (Grant No. 50595412)the National Basic Research Program of China ("973" Program) (Grant No. 2009CB219700)
文摘Sensitivities of eigen-solutions to control variables play an important role in microgrid studies,such as coordinated optimal design of controllers and parameters,robust stability analysis on control variables,oscillation modes analysis on a system,etc.Considering the importance of sensitivities and the complexity of state matrix in a microgrid,parameter perturbations are utilized in this paper to analyze the construction characteristics of state matrix.Then,the sensitivities of eigenvalues and eigenvectors to control variables are obtained based on the first-order matrix perturbation theory,which makes the complex derivations of sensitivity formulas and repeated solutions of eigenvalue problem unnecessary.Finally,the effectiveness of the matrix perturbation based approach for sensitivity calculation in a microgrid is verified by a numerical example on a low-voltage microgrid prototype.