Larson Davis SoundExpert LxT, Руководство пользователя

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LxT Manual Overall Tab
5-13
value of Criterion Time is set by selecting predefined setups,
as described in “Predefined Setups” or by entering
numerical values, as described in “Threshold and Criterion”.
For example, suppose a measurement was performed over a
time period of ten minutes. The value of TWA(8) would be
the same as the TWA measured over an eight hour period if
there were no other sound exposure other than that which
occurred during that ten minute period.
ProjTWA
The ProjTWA (Projected Time Weighted Average) is
calculated from data measured during the measurement run
time and calculated for the user-defined Criterion Time, in
this case 8 hours. Continuing with the example in the
previous paragraph, the ProjTWA for that ten minute
measurement represents the value of TWA that would be
measured if the noise measured during the ten minute period
had continued for eight hours.
L
ep,d
The Daily Personal Noise Exposure, L
ep,d
is calculated from
data measured during the run time of the measurement.
DOSE
Dose is based on data measured during the run time
calculated for the user-defined Criterion Time and Criterion
Level (100% definition). For example, suppose a
measurement was performed over a time period of ten
minutes. The value of Dose would be the same as the Dose
measured over an eight hour period if there were no other
sound exposure other than that which occurred during that
ten minute period.
ProjDOSE
Projected Dose is based on data measured during the run
time and calculated for the user-defined Criterion Time and
Criterion Level (100% definition). Continuing with the
example in the above paragraph, the Projected Dose for that
ten minute measurement represents the value of Dose that
would be measured if the noise measured during the ten
minute period had continued for eight hours.
The remainder of the display shows the parameters used for
the measurement: Frequency Weighting, Exchange Rate,
Threshold and Criterion (time and level).