Outsource Industries Inc. OSIPSSLTX 用户手册
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Appendix A
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The Sound Localization Guidebook Prototype
The Sound Localization Guidebook Prototype
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Appendix A
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77
traffi c on the parallel street remains as an indication of
relative position.
relative position.
These are just some examples of situations in which
the exercises in this manual can be applied to everyday
tasks. However, the skills developed in this manual can
be elaborated upon to develop more sophisticated uses
of sound for O&M tasks. There are many subtle acoustic
phenomena that people learn through trial and error
(Worchel & Mauney, 1950) and use unconsciously (Juurmaa,
1970a). Being able to localize discrete sounds in the
environment and paying more attention to sounds around
a person can lead that person to be aware of different kinds
of sounds around them. For example, when a discrete
sound source is blocked by an object, that sound lowers
in intensity. The resulting “sound shadow” can be used to
detect objects. With practice, very slender objects such as
poles and small trees can be detected in this way. Moving
past such a sound shadow makes it more apparent than just
standing in front of it.
the exercises in this manual can be applied to everyday
tasks. However, the skills developed in this manual can
be elaborated upon to develop more sophisticated uses
of sound for O&M tasks. There are many subtle acoustic
phenomena that people learn through trial and error
(Worchel & Mauney, 1950) and use unconsciously (Juurmaa,
1970a). Being able to localize discrete sounds in the
environment and paying more attention to sounds around
a person can lead that person to be aware of different kinds
of sounds around them. For example, when a discrete
sound source is blocked by an object, that sound lowers
in intensity. The resulting “sound shadow” can be used to
detect objects. With practice, very slender objects such as
poles and small trees can be detected in this way. Moving
past such a sound shadow makes it more apparent than just
standing in front of it.
As a person practices being able to localize different kinds
of sounds in different environments, perhaps beginning
with more obvious phenomena such as sound shadows,
it will become apparent that there are other ways to use
sound. The physics behind sound phenomena do not have
to be understood for a person to be able to make practical
use of the effects. While the human perceptual system is
not sensitive enough to use echoes the same way bats or
dolphins can, in limited situations we can use echoes to
determine distances. This is generally when the distances are
of sounds in different environments, perhaps beginning
with more obvious phenomena such as sound shadows,
it will become apparent that there are other ways to use
sound. The physics behind sound phenomena do not have
to be understood for a person to be able to make practical
use of the effects. While the human perceptual system is
not sensitive enough to use echoes the same way bats or
dolphins can, in limited situations we can use echoes to
determine distances. This is generally when the distances are
very large and there is a lot of space between several large
objects (like on a grassy area among several buildings on a
college campus).
objects (like on a grassy area among several buildings on a
college campus).
Refl ective environments (those with walls or borders of
some sort) or the presence of large objects create a fi eld
of refl ected sound that the human auditory system can
use, beyond the localization of direct sounds. The acoustic
fi eld, comprised of direct sounds and all of the refl ections
off walls, ceilings, and objects, is somewhat analogous to
the visual fi eld (Schwartz, 1984). Movement through this
acoustic fi eld allows a person to gain information about the
surroundings. The ratio of direct sound to refl ected sound
in this acoustic fi eld can be used to determine distances
to sounds (Zahorik, 2002b), and the pattern of refl ected
sound can provide information about the size and structure
of a room (Clifton, Freyman, & Meo, 2002). How quickly
the reverberations fade away or whether they are refl ected
more strongly from one area than another (because of
room geometry or building materials, for example) make
different rooms or objects sound different from each other.
Rooms of different sizes will sound different whether the
person is actively making noise (footsteps, cane taps) or just
standing still but moving through the sound fi eld helps the
perception. The size and shape of the room and, to some
degree, the material the walls are made of and how many
windows there are, affects how sound bounces around in
the room. There is always sound around you, even if you are
trying to be very quiet. So just standing in the middle of a
large room will sound different from standing in the middle
of a small room. With practice and consistent exposure to a
some sort) or the presence of large objects create a fi eld
of refl ected sound that the human auditory system can
use, beyond the localization of direct sounds. The acoustic
fi eld, comprised of direct sounds and all of the refl ections
off walls, ceilings, and objects, is somewhat analogous to
the visual fi eld (Schwartz, 1984). Movement through this
acoustic fi eld allows a person to gain information about the
surroundings. The ratio of direct sound to refl ected sound
in this acoustic fi eld can be used to determine distances
to sounds (Zahorik, 2002b), and the pattern of refl ected
sound can provide information about the size and structure
of a room (Clifton, Freyman, & Meo, 2002). How quickly
the reverberations fade away or whether they are refl ected
more strongly from one area than another (because of
room geometry or building materials, for example) make
different rooms or objects sound different from each other.
Rooms of different sizes will sound different whether the
person is actively making noise (footsteps, cane taps) or just
standing still but moving through the sound fi eld helps the
perception. The size and shape of the room and, to some
degree, the material the walls are made of and how many
windows there are, affects how sound bounces around in
the room. There is always sound around you, even if you are
trying to be very quiet. So just standing in the middle of a
large room will sound different from standing in the middle
of a small room. With practice and consistent exposure to a
17820 Sound Local.ind 76-77
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