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A Study on Features Extraction for HMM Based Anomalous Signal Detection from Waveform Images of ELF Magnetic Signals

Detection of seismic radiation emitted from the earth’s crust can be used for predicting earthquakes. We have been observing electromagnetic (EM) waves in the extremely low frequency (ELF) band. However, the database of seismic radiation signals is not large enough for developing detection methods for anomalous signals from the EM wave data. Previous studies on anomaly detection based on hidden Markov model yielded good results but have not addressed certain problems with the input data. In this paper, we discuss these problems and propose a revised method which achieves better performance in detecting anomalous signals from the waveform images of the ELF magnetic signals.