中国物理B ›› 2026, Vol. 35 ›› Issue (4): 45203-045203.doi: 10.1088/1674-1056/ae37f5
Haipeng Quan(全海鹏)1,2,†, Liqing Xu(徐立清)2, Chaowei Mai(麦晁玮)3, Yan Chao(晁燕)2,‡, Yuhang Wang(王宇航)4, and EAST Team2
Haipeng Quan(全海鹏)1,2,†, Liqing Xu(徐立清)2, Chaowei Mai(麦晁玮)3, Yan Chao(晁燕)2,‡, Yuhang Wang(王宇航)4, and EAST Team2
摘要: Sawtooth phenomena are a central topic in tokamak fusion research; nevertheless, different sawtooth classes differ markedly in underlying physics, statistical abundance and diagnostic definition. This paper focuses exclusively on regular complete sawtooth — ideal, 1/1 internal-kink-driven events with full magnetic reconnection — which are the most frequent, unambiguously identifiable and theoretically best characterized (hereafter, all references to "sawtooth" denote this specific class). Compound crashes, partial-reconnection events and fast-ion-induced giant sawtooth are deliberately excluded because of their limited data volume and still-contested classification criteria, the inclusion of which would introduce intolerable label noise and theoretical ambiguity. To this aim, we propose a machine-learning-based temporal binary-classification framework that converts multi-diagnostic, high-resolution signals into precise labels distinguishing "oscillation" from "quiet" windows for this specific category, thereby supplying critical timing information for active control. A large-scale database covering 124 discharges and hundreds of millions of samples was constructed, and three representative algorithms — logistic regression, decision tree and random forest — were trained and compared. Among them, logistic regression achieved the best and most robust performance, reaching 95 % accuracy on an independent test set and significantly outperforming the other models. Furthermore, shapley additive explanations (SHAP) was innovatively employed to quantify the contribution magnitude and direction of key physical features to the onset of regular 1/1 sawtooth, substantially enhancing model interpretability and physical fidelity. The study provides an efficient and robust predictor for the active intervals of ordinary 1/1 sawtooth; the uncovered correlations between physical drivers and sawtooth behavior lay a solid foundation for deepening the understanding of regular sawtooth evolution and for optimizing control strategies, thereby holding significant promise for improving the operational stability of fusion plasmas.
中图分类号: (Macroinstabilities (hydromagnetic, e.g., kink, fire-hose, mirror, ballooning, tearing, trapped-particle, flute, Rayleigh-Taylor, etc.))