To take the seismic zone that includes the great shock with M S8.5 as the statistical unit of estimating b value can often lead to more large variance, because the seismogenic zone of the great shock with M...To take the seismic zone that includes the great shock with M S8.5 as the statistical unit of estimating b value can often lead to more large variance, because the seismogenic zone of the great shock with M S8.5 are larger than that delineated in general seismic zone. Two-level statistical units are considered in this paper. The seismic province is the first level unit that is suitable for group of earthquakes including the great shock of M S8.5. A seismic province can be divided into several seismic zones. They can be taken as the second level unit for group of quakes in which the super magnitude of the greatest shock do not exceed 8. Because of the nonstationarity in time of seismic activity, the unbalancedness of data and differential of seismic temporal series feature in different areas need to be considered when we select the time period for estimating b value. According to local conditions, the time period is selected at one′s discretion in order to reflect seismicity level of this statistical unit in future 100 years.展开更多
海洋数据具有多源、多类、多维、海量等特点,是一种典型的大数据,海洋大数据上的快速查询是该领域各类应用的基本需求.提高查询速度的关键是建立一个完善的索引结构,为此提出了一种基于时间间隔B+-tree和HSP-tree的多层索引架构ML-index...海洋数据具有多源、多类、多维、海量等特点,是一种典型的大数据,海洋大数据上的快速查询是该领域各类应用的基本需求.提高查询速度的关键是建立一个完善的索引结构,为此提出了一种基于时间间隔B+-tree和HSP-tree的多层索引架构ML-index(multi-layer index),分别制定样本驱动的数据融合机制(adaptive method of data merging strategy)以确定分布式时态数据分区;并基于海洋数据特性、数据单元饱和度等,提出了一种自适应空间划分方法(adaptive space partition),在此基础上建立HSP-tree作为辅助索引.实验验证在海洋数据模式下,提出的多层索引结构保证了海洋数据的查询速度,逼近线性的时间复杂度.展开更多
文摘To take the seismic zone that includes the great shock with M S8.5 as the statistical unit of estimating b value can often lead to more large variance, because the seismogenic zone of the great shock with M S8.5 are larger than that delineated in general seismic zone. Two-level statistical units are considered in this paper. The seismic province is the first level unit that is suitable for group of earthquakes including the great shock of M S8.5. A seismic province can be divided into several seismic zones. They can be taken as the second level unit for group of quakes in which the super magnitude of the greatest shock do not exceed 8. Because of the nonstationarity in time of seismic activity, the unbalancedness of data and differential of seismic temporal series feature in different areas need to be considered when we select the time period for estimating b value. According to local conditions, the time period is selected at one′s discretion in order to reflect seismicity level of this statistical unit in future 100 years.
文摘海洋数据具有多源、多类、多维、海量等特点,是一种典型的大数据,海洋大数据上的快速查询是该领域各类应用的基本需求.提高查询速度的关键是建立一个完善的索引结构,为此提出了一种基于时间间隔B+-tree和HSP-tree的多层索引架构ML-index(multi-layer index),分别制定样本驱动的数据融合机制(adaptive method of data merging strategy)以确定分布式时态数据分区;并基于海洋数据特性、数据单元饱和度等,提出了一种自适应空间划分方法(adaptive space partition),在此基础上建立HSP-tree作为辅助索引.实验验证在海洋数据模式下,提出的多层索引结构保证了海洋数据的查询速度,逼近线性的时间复杂度.