Cochlea a protein motor called prestin on their outer membranes; it generates additional movement that couples back to the fluid–membrane wave. This "active amplifier" is essential in the ear's ability to amplify weak sounds. The active amplifier also leads to the phenomenon of soundwave vibrations being emitted from the cochlea back into the ear canal through the middle ear (otoacoustic emissions). Otoacoustic emissions are due to a wave exiting the cochlea via the oval window, and propagating back through the middle ear to the eardrum, and out the ear canal, where it can be picked up by a microphone. Otoacoustic emissions
Human-body model Human-body model The human-body model (HBM) is the most commonly used model for characterizing the susceptibility of an electronic device to damage from electrostatic discharge (ESD). The model is a simulation of the discharge which might occur when a human touches an electronic device. The HBM definition most widely used is the test model defined in the United States military standard, MIL-STD-883, Method 3015.9, Electrostatic Discharge Sensitivity Classification. This method establishes a simplified equivalent electrical circuit and the necessary test procedures required to model an HBM ESD event. An internationally widely used standard is JEDEC standard JS-001. HBM is used