结合上海轨道交通AFC(Automatic Fare Collection)运营管理数据仓库海量高维数据的特点,通过对传统和游标两种不同访问数据编程方法的比较和应用,研究和提出利用游标技术提高数据仓库数据统计效率的方法,并给出这两种数据访问方法关于...结合上海轨道交通AFC(Automatic Fare Collection)运营管理数据仓库海量高维数据的特点,通过对传统和游标两种不同访问数据编程方法的比较和应用,研究和提出利用游标技术提高数据仓库数据统计效率的方法,并给出这两种数据访问方法关于部分统计效率的对比结果。展开更多
The formation of oil-water emulsion often occurs when oil is spilled into the ocean. Oil weighting factor of oil-water emulsion is one of the most important parameters for emergent oil-spill microwave monitoring. A ne...The formation of oil-water emulsion often occurs when oil is spilled into the ocean. Oil weighting factor of oil-water emulsion is one of the most important parameters for emergent oil-spill microwave monitoring. A new method is proposed here to evaluate the oil weighting factor based on fractional Weierstrass scattering model. By using the proposed method, we analyze the Uninhabited Aerial Vehicle Synthetic Aperture Radar(UAVSAR) L-band fully polarimetric data acquired during 2010 Deepwater Horizon oil spill disaster event in the Gulf of Mexico. The result shows that our method performs well in evaluating oil weighting factor of oil-covered area.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 61331021)
文摘The formation of oil-water emulsion often occurs when oil is spilled into the ocean. Oil weighting factor of oil-water emulsion is one of the most important parameters for emergent oil-spill microwave monitoring. A new method is proposed here to evaluate the oil weighting factor based on fractional Weierstrass scattering model. By using the proposed method, we analyze the Uninhabited Aerial Vehicle Synthetic Aperture Radar(UAVSAR) L-band fully polarimetric data acquired during 2010 Deepwater Horizon oil spill disaster event in the Gulf of Mexico. The result shows that our method performs well in evaluating oil weighting factor of oil-covered area.