product event
3.An event-driven process chain (EPC) model for product development was discussed and a formal representation of EPC presented.
9.These subjects accepted various combinative auditory tests with pure tone threshold audiometry (PTA), acoustic impedance audiometry, 40 Hertz Auditory Event-related Potential(40 Hz AERP), Auditory brainstem response test (ABR), Auditory mulit-frequency steady-state responses(ASSR), Distortion product otoacoustic emissions(DPOAEs).
10.Methods:92 posttraumatic patients (113 ears) complained hearing loss were treated by our hospital. They were examined by test of pure tone hearing threshold (PTHT), test of acoustic immittance (AI), test of 40Hz auditory event related potentials (40 Hz AERP), test of auditory brainstem response(ABR) and test of distortion product otoacoustic emission(DPOAE).

