The Detection of Abnormal Data in Marine Survey
Huang Motao, Zhai Guojun, Wang Rui Ouyang Yongzhong, Guan Zheng (Tianjin Institute of Hydrographic Surveying and Charting, Tianjin, 300061)
Blunder detection is a topic of great interest to surveyors and mappers because undetected blunders significantly distort the observed parameters, e.g., soundings. Based on an analysis of the characteristic of marine surveying, a robust method for the detection of abnormal data (include blunders) in marine measurements is proposed in this paper, which is called the robust interpolation comparison test based on robust M estimation by an iterative calculation procedure. Some questions involved in the implement of the suggested method are discussed in detail. Compared to the existing methods, the new method has more strong capacity of locating abnormal data. A simulation study and an actual numerical example for the process of multibeam soundings are given to test the performance of the proposed method. The results have illustrated the effectiveness of the method in the detection and identification of multiple blunders. The use of the new method will play an important role in improving the quality and reliability of marine measurements in our country.