HY-1C卫星运行轨道的计算研究

轨道数据是卫星资料处理过程涉及的重要参数,高质量HY-1 C卫星产品离不开准确的轨道计算.本文从两行报(Two-Line Orbital Element,TLE)中提取数据,使用STK(Satellite Tool Kit)软件准确模拟出卫星轨道并输出星历表,通过比较两种计算HY-1 C卫星轨道算法的精度,评估摄动因素...     

面向海洋观测与模式数据的客户端软件设计与实现

针对面向海洋观测与模式数据的客户端软件开发工作量大和通用性低的问题,结合传感器观测数据和模式数据的特点,提出了面向海洋观测与模式数据的客户端软件设计模型,通过原型系统验证了模型设计的有效性。该设计模型对于海洋观测与模式数据客户端软件的高效率开发具有重要作用。     

基于相空间重构与模糊神经网络的海温垂直分布预测模型

在海温预报中引入混沌理论,将相空间重构与模糊神经网络相结合,提出了海温垂直建模预测模型。通过相空间重构,把海温时间序列拓展为多维序列,而多维序列包含着各态历经的信息,从而挖掘出了丰富的海温变化空间的信息,有利于模糊神经网络的训练。利用建立好的模糊神经网络模型,较好地对海温的垂直结构进行了建模、训练和预测。实际的预测结果表明,该模型预报精度较高,超前1~5个月的预测值的相对误差均控制在10%以内,预测结果可以为业务工作提供一定的参考与借鉴。     

地壳形变对航天测控站站址坐标影响的分析

航天测控站分布在全球不同的板块,其站址坐标随地壳形变而发生变化。分析了中国大陆区域的地壳形变运动速率,讨论了地壳形变对航天测控站站址坐标的影响,提出了改正措施。     

Process-based model for nearshore hydrodynamics, sediment transport and morphological evolution in the surf and swash zones

Hydrodynamics and sediment transport in the nearshore zone were modeled numerically taking into account turbulent unsteady flow. The flow field was computed using the Reynolds Averaged Navier–Stokes equations with a k–ε turbulence closure model, while the free surface was tracked using the Volume-Of-Fluid technique. This hydrodynamical model was supplemented with a cross-shore sediment transport formula to calculate profile changes and sediment transport in the surf and swash zones. Based on the numerical solutions, flow characteristics and the effects of breaking waves on sediment transport were studied. The main characteristic of breaking waves, i.e. the instantaneous sediment transport rate, was investigated numerically, as was the spatial distribution of time-averaged sediment transport rates for different grain sizes. The analysis included an evaluation of different values of the wave friction factor and an empirical constant characterizing the uprush and backwash. It was found that the uprush induces a larger instantaneous transport rate than the backwash, indicating that the uprush is more important for sediment transport than the backwash. The results of the present model are in reasonable agreement with other numerical and physical models of nearshore hydrodynamics. The model was found to predict well cross-shore sediment transport and thus it provides a tool for predicting beach morphology change.