Using the SAS software, the data of environmental factors vs. red tide biomass were analysed during the process of Skeletonema costatum red tide which broke out in the Changjiang Estuary on June 9～15, 1990. The resul...Using the SAS software, the data of environmental factors vs. red tide biomass were analysed during the process of Skeletonema costatum red tide which broke out in the Changjiang Estuary on June 9～15, 1990. The results of the multivariate statistical analysis show that the environmental factors are similar in their developing and maintenance periods and that the values of environmental factors begin to be restored to normal levels during the disappearing period.The results obtained from using the methods of correlation, variable cluster and main component analyses are basically identical. The important factors contributing to the occurrence of this red tide are atmospherical pressure, water temperature, salinity, pH, No3-, -N, Po43--P and Fe, among which,salinity, Fe and PO43--P are the leading factors which have triggered the occurrence of the red tide as determined by the step-by-step regression analysis. Meanwhile, the linear discrimination functions have been established for the red tide. The environmental factor data of another occurring process of Skeletonema costatum red tide in the Changjiang Estuary have been chosen for red tide discrimination with satisfactory results.展开更多
为了更好地削弱倾角歧视影响,将叠前时间偏移/反偏移与输出道成像方式的共反射面元叠加算法(Common Reflection Surface Stack by the Output Imaging Scheme,以下简称CRS-OIS)相结合,把常规预处理后的地震数据进行叠前时间偏移映射到...为了更好地削弱倾角歧视影响,将叠前时间偏移/反偏移与输出道成像方式的共反射面元叠加算法(Common Reflection Surface Stack by the Output Imaging Scheme,以下简称CRS-OIS)相结合,把常规预处理后的地震数据进行叠前时间偏移映射到成像空间,在该空间内实施CRS-OIS处理,再用相同的速度场将其反偏移到叠前数据空间。基于这种处理流程不仅得到信噪比明显提高的叠前地震数据,同时削弱了CRS叠加方法固有的倾角歧视影响。理论数据与实际资料的处理结果均证实了该法的有效性和实用性。展开更多
文摘Using the SAS software, the data of environmental factors vs. red tide biomass were analysed during the process of Skeletonema costatum red tide which broke out in the Changjiang Estuary on June 9～15, 1990. The results of the multivariate statistical analysis show that the environmental factors are similar in their developing and maintenance periods and that the values of environmental factors begin to be restored to normal levels during the disappearing period.The results obtained from using the methods of correlation, variable cluster and main component analyses are basically identical. The important factors contributing to the occurrence of this red tide are atmospherical pressure, water temperature, salinity, pH, No3-, -N, Po43--P and Fe, among which,salinity, Fe and PO43--P are the leading factors which have triggered the occurrence of the red tide as determined by the step-by-step regression analysis. Meanwhile, the linear discrimination functions have been established for the red tide. The environmental factor data of another occurring process of Skeletonema costatum red tide in the Changjiang Estuary have been chosen for red tide discrimination with satisfactory results.
文摘为了更好地削弱倾角歧视影响,将叠前时间偏移/反偏移与输出道成像方式的共反射面元叠加算法(Common Reflection Surface Stack by the Output Imaging Scheme,以下简称CRS-OIS)相结合,把常规预处理后的地震数据进行叠前时间偏移映射到成像空间,在该空间内实施CRS-OIS处理,再用相同的速度场将其反偏移到叠前数据空间。基于这种处理流程不仅得到信噪比明显提高的叠前地震数据,同时削弱了CRS叠加方法固有的倾角歧视影响。理论数据与实际资料的处理结果均证实了该法的有效性和实用性。
文摘针对经典的李氏指数法(Lyapunov Exponential Method)等混沌相变判别方法复杂度高的问题,提出了一种应用锁相环技术判别混沌相变的新方法。首先,理论推导了混沌系统的解析特性,分析了系统在不同相态下含有的频率成分;然后,构建了针对混沌系统的数字锁相环模型,研究锁相环下混沌态和大周期态呈现的频率特性;最后,提出了一种基于锁相环技术的混沌相变判别新方法。仿真实验显示,相比于李氏指数法,所提方法判别速度快一个数量级,检测差错率为0时,性能提高近2 d B。新方法应用锁相环技术,简便易行,判别速度快,为混沌相变判别的工程应用提供了新的手段。
