Figure 11. A pump ID06 operation sound data of 6 dB SNR ( left ) and − 6 dB SNR ( right ). Projections Figure 11. A pump ID06 operation sound data of 6 dB SNR (left) and − 6 dB SNR (right). Projections of 64 × 313 dimensions log-Mel spectrogram features onto the estimated 2D space by t-SNE. The of 64 × 313 dimensions log-Mel spectrogram features onto the estimated 2D space by t-SNE. The blue and red dots represent the normal condition and the anomalous condition, respectively. blue and red dots represent the normal condition and the anomalous condition, respectively.