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挖掘运动对象的周期行为

Mining Periodic Behaviors for Moving Objects
课程网址: http://videolectures.net/kdd2010_li_mpbm/  
主讲教师: Zhenhui Li
开课单位: 宾夕法尼亚州立大学
开课时间: 2010-10-01
课程语种: 英语
中文简介:
周期性是移动物体经常发生的现象。寻找周期性行为对于理解物体运动至关重要。然而,周期性行为可能是复杂的,涉及多个交错周期,部分时间跨度,以及时空噪声和异常值。在本文中,我们解决了挖掘移动物体的周期性行为的问题。它涉及两个子问题:如何检测复杂运动中的周期,以及如何挖掘周期性运动行为。我们的主要假设是观察到的运动是由与某些参考位置相关的多个交错周期性行为产生的。基于这个假设,我们提出了一个两阶段算法,即Periodica,来解决这个问题。在第一阶段,提出观察点的概念来捕获参考位置。通过观察点,可以使用组合傅立叶变换和自相关的方法来检索运动中的多个周期。在第二阶段,提出概率模型来表征周期性行为。对于特定时期,通过分层聚类从部分运动序列统计推广周期性行为。对合成数据集和实际数据集的实证研究证明了我们的方法的有效性。
课程简介: Periodicity is a frequently happening phenomenon for moving objects. Finding periodic behaviors is essential to understanding object movements. However, periodic behaviors could be complicated, involving multiple interleaving periods, partial time span, and spatiotemporal noises and outliers. In this paper, we address the problem of mining periodic behaviors for moving objects. It involves two sub-problems: how to detect the periods in complex movement, and how to mine periodic movement behaviors. Our main assumption is that the observed movement is generated from multiple interleaved periodic behaviors associated with certain reference locations. Based on this assumption, we propose a two-stage algorithm, Periodica, to solve the problem. At the first stage, the notion of observation spot is proposed to capture the reference locations. Through observation spots, multiple periods in the movement can be retrieved using a method that combines Fourier transform and autocorrelation. At the second stage, a probabilistic model is proposed to characterize the periodic behaviors. For a specific period, periodic behaviors are statistically generalized from partial movement sequences through hierarchical clustering. Empirical studies on both synthetic and real data sets demonstrate the effectiveness of our method.
关 键 词: 周期性行为; 物体运动; 傅立叶变换
课程来源: 视频讲座网
最后编审: 2019-05-11:lxf
阅读次数: 69