Biomedical Engineering Reference
In-Depth Information
Elasticity.
The ability of an object
or material to resume its normal
shape after being compressed; the
measure of stiffness of an object or
material.
Electromagnetic Interference
(EMI).
Disturbance that affects
an electrical circuit due to either
electromagnetic induction or
electromagnetic radiation emitted
from an external source.
Electromagnetic Radiation (EMR).
A
kind of radiation that includes visible
light, radio waves, gamma rays, and
x-rays, in which electric and magnetic
fields vary simultaneously; wireless
hearing assistive technologies use
certain frequency bands on the EM
radiation spectrum.
FlashVP6.
A proprietary video codec
(file) developed by On2 Technologies
that is used in Adobe Flash Player 8
and newer versions.
FM Boot.
See
Audio Shoe
.
Frequency.
The rate at which a
vibration occurs that constitutes a
wave, either in a material (as in sound
waves), or in an electromagnetic field
(as in radio waves and light), usually
measured per second.
Frequency Hopping Spread Spectrum
(FHSS) Technology.
Wireless
technology in which the transmission
frequencies are determined by a
spreading, or hopping, code. The
receiver must be set to the same
hopping code and must listen to the
incoming signal at the right time and
correct frequency in order to properly
receive the signal.
Frequency Lowering.
A way of
increasing the access to high-
frequency sounds, by digital
manipulation, to a lower-frequency
range where sounds are more likely to
be audible.
Frequency Modulation (FM).
A way of
encoding signals over an alternating
current wave through forced
change in frequency; the manner
of transmission for some hearing
assistive technologies (HATs).
Giant Magnetoresistor (GMR).
An
electronic component that produces
a large change in resistance of a
conducting layer. “Giant” refers
to its very large electrical signal.
GMR is used in hearing aids with
autotelecoils.
Global System for Mobile (GSM)
Communications Technology.
An
open, digital cellular technology that
transmits voice and data services for
mobile devices over the 900 MHz
band.
H.264.
See
MPEG-4
.
Head Shadow Effect.
A region of
reduced amplitude of a sound in one
ear because it is obstructed by the
head. The obstruction caused by the
head can account for a significant
attenuation of overall intensity as well
as cause a filtering effect.
Hearing Aid.
An electroacoustic device
that is designed to amplify sound
for the wearer. The aim of these
medical, FDA-regulated devices is to
make speech more intelligible, and to
correct impaired hearing as measured
by audiometry.
