Sand cay is a special kind of islet formed by coral detritus and bioclast, which is common in Nansha Islands of China. Some sand cays play an important role in ocean strategy and economy, but surprisingly we know litt...Sand cay is a special kind of islet formed by coral detritus and bioclast, which is common in Nansha Islands of China. Some sand cays play an important role in ocean strategy and economy, but surprisingly we know little about them, especially those recently formed sand cays. In this research, we monitor migration of a new sand cay in Nanxun Jiao（Gaven Reef） using a series of Quick Bird and World View-2 satellite images between June 2006 and August 2013. We conduct a regression between migration distance and wind observational data to examine the migration patterns of the new sand cay. The migration distance is calculated based on the sand cay locations extracted based on Normalized Difference Water Index（NDWI）. The wind observational data downloaded from NOAA are reformed into four wind direction vectors. Based on the results of regression, we concluded that the migration of the new sand cay on Nanxun Jiao was significantly associated with the east, west and north wind.East wind was the main influence factor of the migration; its impact strength was almost twice as the west and north wind. The south wind has little effect on the migration of the sand cay, which is partly blocked by the artificial structure in the south.展开更多
Green sand casting is still a main method in the world at present and it isvery significant to develop the technology of controlling green sand quality. A new concept, fromcontents test to contents control, is advance...Green sand casting is still a main method in the world at present and it isvery significant to develop the technology of controlling green sand quality. A new concept, fromcontents test to contents control, is advanced. In order to realize the new idea, a new method toon-line test active clay and moisture of green sand - double powers energizing alternately (DPEA)method is put forwards. The principle of the new method is to energize standard sand sample with ACand DC powers and to test the electric parameters, and then, to calculate active clay and moistureof green sand by using artificial neural network (ANN). Based on this new method, a directoptimizing system for controlling green sand quality is developed. Techniques about testing andcontrolling methods, hardware and software are discussed.展开更多
基金National Sea Islands Protection and Management Programme
文摘Sand cay is a special kind of islet formed by coral detritus and bioclast, which is common in Nansha Islands of China. Some sand cays play an important role in ocean strategy and economy, but surprisingly we know little about them, especially those recently formed sand cays. In this research, we monitor migration of a new sand cay in Nanxun Jiao（Gaven Reef） using a series of Quick Bird and World View-2 satellite images between June 2006 and August 2013. We conduct a regression between migration distance and wind observational data to examine the migration patterns of the new sand cay. The migration distance is calculated based on the sand cay locations extracted based on Normalized Difference Water Index（NDWI）. The wind observational data downloaded from NOAA are reformed into four wind direction vectors. Based on the results of regression, we concluded that the migration of the new sand cay on Nanxun Jiao was significantly associated with the east, west and north wind.East wind was the main influence factor of the migration; its impact strength was almost twice as the west and north wind. The south wind has little effect on the migration of the sand cay, which is partly blocked by the artificial structure in the south.
基金Provincial Outstanding Youth Foundation of Heilongjiang, China.
文摘Green sand casting is still a main method in the world at present and it isvery significant to develop the technology of controlling green sand quality. A new concept, fromcontents test to contents control, is advanced. In order to realize the new idea, a new method toon-line test active clay and moisture of green sand - double powers energizing alternately (DPEA)method is put forwards. The principle of the new method is to energize standard sand sample with ACand DC powers and to test the electric parameters, and then, to calculate active clay and moistureof green sand by using artificial neural network (ANN). Based on this new method, a directoptimizing system for controlling green sand quality is developed. Techniques about testing andcontrolling methods, hardware and software are discussed.
