Measurement of cavitation bubble cluster downstream of sheet cavity

1. 北冰洋的气象资料来自ECMWF和日本气象厅。卫星遥感测得的海冰分布数据来自NSIDC。这些数据来自SSM/I传感器，安装在美国DMSP卫星上。由于海流数据非常有限，我们利用旋转槽进行了基础实验，并在相同条件下进行了数值模拟，考虑采用数值模拟技术。实验洋流显示出与北冰洋表面观测到的洋流相同的模式，这表明西伯利亚和阿拉斯加沿岸河流径流的影响是显著的。采用多层模式的数值模拟也显示出相同的模式，表明该计算机程序可以应用于北冰洋洋流的预测。采集到的数据全部转换成ArcView GIS数据库格式。正因为如此，数据的查看和分析变得很容易。利用本研究开发的gis数据库系统对北冰洋海冰进行了分析。虽然整个冰原的变化主要受风和气温的影响，但部分地区的海冰运动非常复杂。这样就可以提取出各个海域的海冰变化特征。开发了几个接口程序，将GIS与海冰变化预测程序连接起来。因此，开发了一个集数据、地理信息系统和预测计算于一体的系统。利用该系统进行了海冰变化预测计算，验证了该系统的有效性。

1. Meteorological data on the Arctic Ocean were obtained from ECMWF and Japan Meteorological Agency. Sea ice distribution data measured by satellite remote sensing were obtained from NSIDC.These data are of SSM/I sensor, which is installed on the US DMSP satellite.2. Since sea current data is very limited, we performed fundamental experiments using a rotating tank and also numerical simulation with the same condition, considering to use numerical simulation technique. The experimental current showed the same pattern as the observed surface current in the Arctic Ocean, suggesting that the effect of river run-off along the Siberian and Alaska coasts is significant. The numerical simulation using multi-layer model also showed the same pattern, suggesting that this computer program can be applied to predict the Arctic Ocean current.3. All of the collected data were transferred into ArcView GIS database format. Because of this, it has become easy to view and analyze the data.4. The GIS-database system developed in this research was used to analyze the sea ice in the Arctic Ocean. Although the whole ice field changed mainly due to wind and air temperature, some areas showed very complicated sea ice motion. As such, the characteristics of sea ice change can be extracted for each sea area.5. Several interface programs were developed to connect the GIS and sea ice change prediction programs. As a result, an integrated system of data, GIS and prediction computations was developed. Using this system, we executed sea ice change prediction computations, confirming the effectiveness of this system.