User authentication system based on human exhaled breath physics
Fig 5
Flow chart showing the algorithm pipeline, including time series normalization, filtering, feature extraction, feature reduction, and data splitting into training and testing. The time signal shown here is one of the segments of the original time series. Note that the representation of blue bar for training dataset and green bar for testing dataset will be consistent in further discussions in this manuscript. The training data of all users were used for building nC2 binary classifier models, which becomes the process known as enrollment.