Realistic modeling and rendering of dynamic tornado scene is recognized as a challenging task for researchers of computer graphics. In this paper a new physically based method for simulating and animating tornado scen...Realistic modeling and rendering of dynamic tornado scene is recognized as a challenging task for researchers of computer graphics. In this paper a new physically based method for simulating and animating tornado scene is presented. We first propose a Two-Fluid model based on the physical theory of tornado, then we simulate the flow of tornado and its interaction with surrounding objects such as debris, etc. Taking the scattering and absorption of light by the participating media into account, the illumination effects of the tornado scene can be generated realistically. With the support of graphics hardware, various kinds of dynamic tornado scenes can be rendered at interactive rates.展开更多
The correlation and composite analysis are carried out in this paper to study major factors affecting the track of tropical cyclones (TCs) after their landfall in the east of China. The mid-tropospheric environmental ...The correlation and composite analysis are carried out in this paper to study major factors affecting the track of tropical cyclones (TCs) after their landfall in the east of China. The mid-tropospheric environmental steering flow is found to dominate the movement of a TC even after landfall, with the inertia and Coriolis force two other subordinates. A key region is discovered covering the east of China and Yellow Sea, in which the environmental flow significantly affects the movement of TCs making landfall in this part of China. When the subtropical high in this region strengthens and extends westward, accompanied by northward shrink of the westerly trough, the TC tends to move westward after landfall and disappear inland. However, when the subtropical high in this region weakens and shrinks eastward, accompanied by southward push of the westerly trough, the TC tends to recurve after landfall and re-enter the sea at a location to the north of the site of landfall. The environment before the landfall of a TC has little impact on its post-landfall track, which is sensitive to the environmental change 12 – 24 hours after landfall. A 6-hour lag is found between the environmental change and the movement of a TC after landfall.展开更多
Employing Grossman and Helpman＇s ＂protection for sale＂ model, this article uses data on anti-dumping actions from 1999 to 2009 to perform a quantitative analysis of factors influencing India＇s determinations of an...Employing Grossman and Helpman＇s ＂protection for sale＂ model, this article uses data on anti-dumping actions from 1999 to 2009 to perform a quantitative analysis of factors influencing India＇s determinations of anti-dumping duties against China, and reveals the micro-formation mechanism of economic conflicts between China and India. We find that the political power of India＇s anti-dumping plaintiffs markedly increases the tariff level of its final determinations and that the relationship between the import penetration ratio and duty rates depends upon whether the plaintiffs are politically organized. Further, there is a significant positive correlation between India＇s anti-dumping duty rates and its unfavorable trade balance with China. This indicates that in determining anti-dumping duties, Indian authorities are clearly influenced by the political clout of their domestic interest groups. They are also motivated by the desire to keep down China and gain the upper hand in the face-off between the ＂dragon and the elephant.＂展开更多
基金Project supported by the National Basic Research Program (973) of China (No. 2002CB312101) and the National Natural Science Foundation of China (No. 60475013)
文摘Realistic modeling and rendering of dynamic tornado scene is recognized as a challenging task for researchers of computer graphics. In this paper a new physically based method for simulating and animating tornado scene is presented. We first propose a Two-Fluid model based on the physical theory of tornado, then we simulate the flow of tornado and its interaction with surrounding objects such as debris, etc. Taking the scattering and absorption of light by the participating media into account, the illumination effects of the tornado scene can be generated realistically. With the support of graphics hardware, various kinds of dynamic tornado scenes can be rendered at interactive rates.
基金Social Welfare Research Fund for the Research Institutes of Ministry of Science and Technology(2005DIB3J104)Open Fund for Meteorological Research of Zhejiang Province (KF2006008)
文摘The correlation and composite analysis are carried out in this paper to study major factors affecting the track of tropical cyclones (TCs) after their landfall in the east of China. The mid-tropospheric environmental steering flow is found to dominate the movement of a TC even after landfall, with the inertia and Coriolis force two other subordinates. A key region is discovered covering the east of China and Yellow Sea, in which the environmental flow significantly affects the movement of TCs making landfall in this part of China. When the subtropical high in this region strengthens and extends westward, accompanied by northward shrink of the westerly trough, the TC tends to move westward after landfall and disappear inland. However, when the subtropical high in this region weakens and shrinks eastward, accompanied by southward push of the westerly trough, the TC tends to recurve after landfall and re-enter the sea at a location to the north of the site of landfall. The environment before the landfall of a TC has little impact on its post-landfall track, which is sensitive to the environmental change 12 – 24 hours after landfall. A 6-hour lag is found between the environmental change and the movement of a TC after landfall.
基金an interim product of"Research into a Strategic System to Enable Chinese Enterprises to Cope with Trade Barriers against the Background of Prevailing International Trade Protectionism,"a project funded by the National Natural Science Foundation of China for Youth(71203228)
文摘Employing Grossman and Helpman＇s ＂protection for sale＂ model, this article uses data on anti-dumping actions from 1999 to 2009 to perform a quantitative analysis of factors influencing India＇s determinations of anti-dumping duties against China, and reveals the micro-formation mechanism of economic conflicts between China and India. We find that the political power of India＇s anti-dumping plaintiffs markedly increases the tariff level of its final determinations and that the relationship between the import penetration ratio and duty rates depends upon whether the plaintiffs are politically organized. Further, there is a significant positive correlation between India＇s anti-dumping duty rates and its unfavorable trade balance with China. This indicates that in determining anti-dumping duties, Indian authorities are clearly influenced by the political clout of their domestic interest groups. They are also motivated by the desire to keep down China and gain the upper hand in the face-off between the ＂dragon and the elephant.＂
