“…Then, four algorithms—auto-associative neural network, factor analysis, Mahalanobis distance, and singular value decomposition—were applied and their accuracy was compared. Other studies include research using 1D Convolutional Neural Networks [ 16 ], support vector machines [ 17 , 18 , 19 , 20 ], Gaussian process regression [ 21 ], and Genetic algorithms [ 18 , 22 ]. Although these studies propose machine learning methods based on interesting experimental data, they basically remain at the level of damage detection, because it is very difficult to prepare test specimens with various damage geometries in the order of 10 2 or more in experiments.…”