基于改进累积和控制图的GNSS变形信息的识别与预警

Identification and Forewarning of GNSS Deformation Information Based on a Modified Cumulative Sum Control Chart

累积和(cumulative sum,CUSUM)控制图是一种较为成熟的突变点识别方法,可以较为有效地对全球导航卫星系统(global navigation satellite system,GNSS)坐标序列中的变形信息进行识别与预警。然而,对于长时间的连续监测,GNSS坐标序列中不可避免地存在粗差或离群值,其对CUSUM控制图的检测效果有一定的影响。鉴于此,提出了采用基于中位数构建的改进CUSUM控制图进行GNSS坐标序列中变形信息的识别与预警,并给出了该方法的基本原理和算法流程。结果表明:采用改进CUSUM控制图进行变形信息识别和预警的准确度优于传统方法,其灾害预警的误报率显著减小,说明了采用改进CUSUM控制图的必要性和优越性。

Cumulative sum(CUSUM) control chart is a more mature method for outlier identification,which can effectively identify and forewarn the deformation information in the global navigation satellite system(GNSS) coordinate series, but for long-term continuous monitoring, gross errors inevitably exist in the GNSS coordinate series, which has a certain impact on the accuracy of the CUSUM control chart. Therefore, a modified CUSUM control chart based on median was proposed to identify and forewarn the deformation information in the GNSS coordinate series, and its principle and algorithm flow were given. The results show that the accuracy of deformation information identification and forewarning using modified CU-SUM control chart is better than traditional method, and the false alarm rate of the disaster warning are reduced, which shows the necessity and superiority of using the modified CUSUM control chart.