In recent years, Sub-Committee on Undersea Feature Names (SCUFN) has been conducting deliberations on naming undersea features that are entirely or mainly (more than 50%) outside the external limits of the territorial sea, adhering to the principles of not involving sovereignty dispute between countries. In order to participate in undersea feature naming and embody the international responsibility, obligation and influence of the State, Chinese State Oceanic Administration submitted seven undersea name proposals to SCUFN in 2011 for the first time. The “Niao Chao” proposal utilized data of Multi-Beam Echo Sounder were acquired by Chinese research vessel “Dayangyihao” at the Eastern Pacific Rise in Sep 2008.
In this paper, we introduce Total Propagated Error Computation(TPEC)algorithm to improve the efficiency of Multi-Beam Echo-Sounder data(MBES)processing and to avoid losing terrain details in trend surface model and median filter model. The workflow of TPEC algorithm can be summarized as follows: Firstly, compute the Total Propagated Error of MBES data. Next, according to the IHO standard, eliminate noises automatically. Further, generate a plurality of depth and associated uncertainty estimation of grid nodes. Finally, construct “the best” Digital Terrain Model(DTM)based on the principles of density and neighbourhood. Processing of submarine terrain data and establishment of digital terrain model were based on Total Propagated Error Computation algorithm. Material preparation, figure plotting and submission of proposal followed the standardization and procedure of SCUFN.
To evaluate the efficiency and quality of the TPEC algorithm, TPEC algorithm and conventional method are used respectively to process the same MBES data. The conventional method uses man-machine editor to reject gross errors and construct DTM by beam inverse weighting algorithm. TPEC algorithm removes gross errors automatically by filter based on the computation of Total Propagated Error, and builds DTM by the combined estimation of the depth and related Uncertainty. The data processing speed of TPEC algorithm is 5 times of the conventional method. Furthermore, the TPEC model shows much more terrain details than the man-machine model. TPEC algorithm suitable for the research of complex seabed terrain environment such as EPR, provides a possible technological method for the study of international undersea feature naming.
Keywords:
Total Propagated Error Computation(TPEC)Algorithm, Multi-Beam Echo-Sounder，Sub-Committee on Undersea Feature Names (SCUFN), undersea feature naming, Eastern Pacific Rise(EPR)
