[1S5-GS-2] 機械学習：

[1S5-GS-2-03] 物理科学における非常に高精度な機械学習を必要とするアプリケーション：機械学習の手法開発への影響とニューロモルフィックコンピューティングの可能性の検討

〇Sergei Manzhos¹, Manabu Ihara¹, Johann Lüder², Chu-Chen Chueh³, Wen-Ya Lee³, Qun Gao Chen³ (1. Institute of Science Tokyo, 2. National Sun Yat-sen University, 3. National Taiwan University)

キーワード：Machine learning, extremely high accuracy regime, neuromorphic computing

We will demonstrate examples of applications from computational chemistry and materials informatics where "normal", i.e. similar to that typically observed in other applications, accuracy of machine learning (ML) (exemplified by correlation coefficients R between reference and predicted values on the order of 0.9 or even less) is sufficient (such as ML of materials properties) as well as examples of applications where high, with test set R values better than 0.9999 or even 0.99999, accuracy is categorically required. We will demonstrate how this on one hand makes shine nonlinear ML methods where otherwise a polynomial regression would suffice, but on the other hand presents challenges, not observed in more mundane applications, for machine learning with neuromorphic devices that are currently actively researched and that are subject to circuit noise and other circuit instabilities as well as to batch variability of the neuron activation function. We show by numeric simulations how these factors prevent obtaining high ML accuracy. On the example of machine learning of the kinetic energy functional for orbital-free DFT, we show that while restrictions on the shape of the activation function are not critical, circuit noise and instabilities can prevent obtaining the required ML accuracy.