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LW
A[d
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Speed [km/h]
R7
ASJ:GEV
LW=46.9 +30logV
LW=48.5 +28.6logV
LWA determination of passenger car
Measurement site :R7
S A K A M O T O L A B . [Measurement and Evaluation of
Sound Environment in Urban City ] Advanced Mobility Research Center
Environmental Acoust ic Engineer ing
http://www.acoust . i i s .u -tokyo.ac. jp Department of Architecture, Graduate school of Engineer ing
Measurement and Evaluat ion of Sound Environment in Urban City Acoust ic laboratory(Ce-101, Ce-B01)
Welcome to aural demonstration using sound
field simulator!
Measurement and Evaluation of Sound Environment in Urban City
Our laboratory treats various acoustical issues about measurement and evaluation of sound environment in urban city. Evaluation methods of acoustical environment and techniques of control and prediction of sound will be introduced. ◆Development of prediction methods:Numerical analysis ◆Room acoustic design:Auditorium, Music practice room, Open-type classrooms ◆Acoustic measurement:Sound propagation, Sound insulation and absorption ◆Development of sound field simulation:6 channel recording-reproduction system ◆Subjective evaluation:Concert halls, Living environments, Public spaces, Offices, Healthcare facilities, other small spaces such as a car cabin
Sound environment of railway station Measurement of acoustic properties by using a parametric loudspeaker
A parametric loudspeaker, which has super sharp directivity, is expected to enable in-situ measurement of acoustic properties of materials without extraneous diffraction from sample edge or obstructive reflections from room boundaries. Basic examination on the measurement method is being studied experimentally.
Subjective evaluation of noise with tonal components
Tonal components in environmental noise may increase the annoyance to the noise. Auditory experiments are conducted to know how the frequency characteristics affect the subjective perception such as loudness and annoyance.
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-10 -5 0 5 10 15 20
M40
LL
(M)
[phon]
Tonal Audibility [dB]
40 Hz
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-10 -5 0 5 10 15 20
M200
LL
(M) [p
hon]
Tonal Audibility [dB]
200 Hz
⬜︎ Standard stimuli ● Comparison stimuli
Results of loudness matching test. (back ground noise : -4 oct /dB)
In a railway station, an appropriate announcement is very important for users’ convenience and safety. A field survey and a subjective experiment were conducted. By using a 3D sound field simulation system, listening difficulty and loudness of the announcement were evaluated.
Subjective evaluation by using 3D sound field simulation system
Field measurement
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データ 1 14:04:39 平成 30/03/29
新宿
品川
東京
大宮
上野
S/N
● UN ST.× OM ST.▲ TK ST.□ SN ST.◆ SJ ST.
-5 0 5 10 15 20SNR [dB]
List
enin
g d
iffi
cult
y
5. Extremely
4. Very
3. Moderately
2. Slightly
1. Not at all
Relationships between listening difficulty and SNR
Parametric loudspeaker
Free field measurement
In-situ measurement
Development of prediction method of road traffic noise
Road traffic noise is one of the most important issues for environmental assessment and accurate prediction method is essential for appropriate maintenance of living environment. Such a prediction method has been developed from viewpoints of sound emission and propagation.
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Par
amet
er a
[dB
]
L M GEV HVLV
Vehicle class
LWA = a +30log10Vn 11
n 15n 18 n 15 n 16
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