Figure 13. A pump ID06 operation sound data of 6 dB SNR ( left ) and − 6 dB SNR ( right ). Projections Figure 13. A pump ID06 operation sound data of 6 dB SNR (left) and − 6 dB SNR (right). Projections of the 320-dimensional log-Mel spectrogram feature onto the estimated 2D space by t-SNE. The blue of the 320-dimensional log-Mel spectrogram feature onto the estimated 2D space by t-SNE. The blue and red symbols represent the normal condition and the anomalous condition, respectively. and red symbols represent the normal condition and the anomalous condition, respectively.