Methods Based on the original low frequency and single ingredient SY-IA tympanometry, the study mainly focused on such aspects as multiple frequency probe tone circuit, constant pressure sound control system, micropressor control system and multiple frequency acoustic immitance & phase angle detection circuit.

The algorithm utilizes density function to initialize cluster centers to select initial cluster centers objectively,it can be used in both on-line detection and retrospective detection,and the quantity of clusters is affected little by the order in which the news stories are processed.