EAST-NBI experimental data processing method based on improved OPTICS algorithm

Abstract Generally, the accuracy of the key-values extraction algorithm of experimental data will affect the adjustment of the operating parameters of the experimental device, especially when the NBI (Neutral Beam Injector) ion source breakdown occurs. The instability of the internal plasma of the ion source caused by the mismatch of operating parameters is the main cause of breakdown of the NBI ion source. For the problem of poor accuracy of the existing key-values extraction algorithms for experimental data, this paper proposes an improved algorithm based on Ordering Points To Identify the Clustering Structure (OPTICS). By improving the judgment of the core-points of the data and the method of searching for core-objects, the time complexity of the algorithm is reduced and the accuracy of the experimental data extraction is improved. The results show that the improved OPTICS algorithm can reach the accuracy of the experimental requirements, meet the data analysis requirements of the EAST-NBI long pulse operation, and can also provide a reference for the failure analysis during the experimental operation.