Horizontal winds in the mesosphere (80-100 km) were measured by meteor radar in Wuhan, China (30° N, 114° E) over a 45-month interval in 2002-2005 and the data examined to investigate the monthly mean be...Horizontal winds in the mesosphere (80-100 km) were measured by meteor radar in Wuhan, China (30° N, 114° E) over a 45-month interval in 2002-2005 and the data examined to investigate the monthly mean behavior of the Ol tide. A clear seasonal variation in amplitude of the O1 tide ranging from -0.3 m/s to 2.6 m/s was observed. In most months, the northward and eastward components differed by about 7 lunar hours with the eastward component leading. Comparison of the amplitudes of the M2 and O1 tides suggests the O1 tide is quite stronger over Wuhan, China. The amplitude ratio of the O1 tide to the M2 tide is quite stronger than that the gravitational potential being 0.41. The vertical wavelength of the O1 tide differs on a monthly basis. Height profiles of the O1 tide showed obvious height variation. The O1 tide is stronger in January and July. In different month, the vertical wavelength for the O1 tide changes considerably at the same height. The year's variation trend of the northward and eastward components is very similar in both phase and amplitude.展开更多
Taizhou Bridge, located at the middle of Jiangsu Province, connecting Taizhou City and Zhenjiang City, started in Dec. 2007. The bridge is the first kilometer level three-pylon suspension bridge in the world, and it a...Taizhou Bridge, located at the middle of Jiangsu Province, connecting Taizhou City and Zhenjiang City, started in Dec. 2007. The bridge is the first kilometer level three-pylon suspension bridge in the world, and it adopts longitudinal herringbone shape steel middle pylon for the first time in the world. The foundation of the middle tower is the deepest underwater caisson in soil on earth. A great many of technical innovations such as the design techniques of three-pylon suspension bridge,precisely locating and bottom-sealing techniques of the large scale caisson foundation, manufacturing, combination techniques of steel and concrete in the middle tower, welding of extra thick steel plate, manufacture and control techniques of abnormal sections of the middle tower and so on were introduced.展开更多
基金Acknowledgements This research was supported by National Natural Science Foundation of China (41104095)
文摘Horizontal winds in the mesosphere (80-100 km) were measured by meteor radar in Wuhan, China (30° N, 114° E) over a 45-month interval in 2002-2005 and the data examined to investigate the monthly mean behavior of the Ol tide. A clear seasonal variation in amplitude of the O1 tide ranging from -0.3 m/s to 2.6 m/s was observed. In most months, the northward and eastward components differed by about 7 lunar hours with the eastward component leading. Comparison of the amplitudes of the M2 and O1 tides suggests the O1 tide is quite stronger over Wuhan, China. The amplitude ratio of the O1 tide to the M2 tide is quite stronger than that the gravitational potential being 0.41. The vertical wavelength of the O1 tide differs on a monthly basis. Height profiles of the O1 tide showed obvious height variation. The O1 tide is stronger in January and July. In different month, the vertical wavelength for the O1 tide changes considerably at the same height. The year's variation trend of the northward and eastward components is very similar in both phase and amplitude.
基金National Science and Technology Support Program of China ( No. 2009BAG15B01)Key Programs for Science and Technology Development of Chinese Transportation Industry( No. 2008-353-332-190)
文摘Taizhou Bridge, located at the middle of Jiangsu Province, connecting Taizhou City and Zhenjiang City, started in Dec. 2007. The bridge is the first kilometer level three-pylon suspension bridge in the world, and it adopts longitudinal herringbone shape steel middle pylon for the first time in the world. The foundation of the middle tower is the deepest underwater caisson in soil on earth. A great many of technical innovations such as the design techniques of three-pylon suspension bridge,precisely locating and bottom-sealing techniques of the large scale caisson foundation, manufacturing, combination techniques of steel and concrete in the middle tower, welding of extra thick steel plate, manufacture and control techniques of abnormal sections of the middle tower and so on were introduced.