针对无线体域网(wireless body area network,WBAN)异常数据检测方法忽视人体异常数据的连续性,缺乏异常数据集检测等问题,提出一种基于Hampel滤波器和DBSCAN分层的WBAN异常数据检测方法。根据时间相关性利用Hampel滤波器检测异常数据点...针对无线体域网(wireless body area network,WBAN)异常数据检测方法忽视人体异常数据的连续性,缺乏异常数据集检测等问题,提出一种基于Hampel滤波器和DBSCAN分层的WBAN异常数据检测方法。根据时间相关性利用Hampel滤波器检测异常数据点,保证数据的连续性,使用改进的基于滑动时间窗的DBSCAN算法,检测异常数据集。实验结果表明,所提方法和其它方法相比,实现了分层的异常数据检测,在保证检测精度的同时准确标注出了异常数据集,具有空间复杂度小的优势。展开更多
How to process aggregate queries over data streams efficiently and effectively have been becoming hot re search topics in both academic community and industrial community. Aiming at the issues, a novel Linked-tree alg...How to process aggregate queries over data streams efficiently and effectively have been becoming hot re search topics in both academic community and industrial community. Aiming at the issues, a novel Linked-tree algorithm based on sliding window is proposed in this paper. Due to the proposal of concept area, the Linked-tree algorithm reuses many primary results in last window and then avoids lots of unnecessary repeated comparison operations between two successive windows. As a result, execution efficiency of MAX query is improved dramatically. In addition, since the size of memory is relevant to the number of areas but irrelevant to the size of sliding window, memory is economized greatly. The extensive experimental results show that the performance of Linked-tree algorithm has significant improvement gains over the traditional SC （Simple Compared） algorithm and Ranked-tree algorithm.展开更多
文摘针对无线体域网(wireless body area network,WBAN)异常数据检测方法忽视人体异常数据的连续性,缺乏异常数据集检测等问题,提出一种基于Hampel滤波器和DBSCAN分层的WBAN异常数据检测方法。根据时间相关性利用Hampel滤波器检测异常数据点,保证数据的连续性,使用改进的基于滑动时间窗的DBSCAN算法,检测异常数据集。实验结果表明,所提方法和其它方法相比,实现了分层的异常数据检测,在保证检测精度的同时准确标注出了异常数据集,具有空间复杂度小的优势。
基金Supported by the National Natural Science Foun-dation of China (60573089) the National 985 Project Fundation(985-2-DB-Y01)
文摘How to process aggregate queries over data streams efficiently and effectively have been becoming hot re search topics in both academic community and industrial community. Aiming at the issues, a novel Linked-tree algorithm based on sliding window is proposed in this paper. Due to the proposal of concept area, the Linked-tree algorithm reuses many primary results in last window and then avoids lots of unnecessary repeated comparison operations between two successive windows. As a result, execution efficiency of MAX query is improved dramatically. In addition, since the size of memory is relevant to the number of areas but irrelevant to the size of sliding window, memory is economized greatly. The extensive experimental results show that the performance of Linked-tree algorithm has significant improvement gains over the traditional SC （Simple Compared） algorithm and Ranked-tree algorithm.
