Geopsy: Multiply - Revision history

Marc at 09:09, 12 March 2010

2010-03-12T09:09:05Z

Clotaire Michel at 15:08, 10 March 2010

2010-03-10T15:08:12Z

Clotaire Michel at 10:16, 10 March 2010

2010-03-10T10:16:02Z

Pierre-Yves Bard: /* Data Conversion */

2010-03-09T08:48:24Z

Data Conversion

Pierre-Yves Bard at 08:42, 9 March 2010

2010-03-09T08:42:17Z

Clotaire Michel: New page: '''Multiply''', reached from the Waveform menu, multiplies the signals in the active signal viewer by a constant value. This is especial...

2010-03-09T08:19:12Z

New page: '''Multiply''', reached from the Waveform menu, multiplies the signals in the active signal viewer by a constant value. This is especial...

New page

'''Multiply''', reached from the [[Geopsy: Waveform Menu|Waveform menu]], multiplies the signals in the active [[Geopsy: Signal Viewer|signal viewer]] by a constant value. This is especially useful for data conversion from counts to velocity or acceleration, for example.
By clicking on Multiply, a pop-up window appears and lets the user enter the value of the multiplication factor.

"Multiply" modifies the [[Geopsy: Temporary Signal|temporary signals]] in the active viewer.

==Data Conversion==
Currently, signals are not converted or corrected by the response file of the acquisition system when [[Geopsy: Import signal files|imported in Geopsy]]. "Multiply" is the only way to convert data from counts or volts delivered by the digitizer into velocity or acceleration. For a recording in velocity, the conversion factor C is computed as follows:

<math>C[(m/s)/count]=\frac{StationConversion [V/count]}{Gain [-] . SensorSensitivity [V/(m/s)] }</math>.

StationConversion is the gain of the station, it represents the inverse of the number of counts used by the station to write a 1 Volt value delivered by the sensor. It may depend on the sampling frequency. Depending on the digitizer it may also be modified by a manual Gain (power of 2) used to adapt the number of bits used to maximize it depending on the signal amplitude. SensorSensitivity is the sensitivity of the sensor, i.e. the number of Volts output for a unit m/s velocity.

===Examples of conversion factors===
*Quanterra Q330 digitizer with Lennartz 5s sensor: <math>C=5.96047e-9 [(m/s)/count]</math>
*Nanometrics Taurus digitizer with Kinemetrics Episensor accelerometer: <math>C=1.58946e-9 [(m/s^2)/count]</math>

@@ Line 1: / Line 1: @@
 [[Image:Multiply.png|thumb|right|200px|Multiply Value pop-up window]]
-'''Multiply''', reached from the [[Geopsy: Waveform Menu|Waveform menu]], multiplies the signals in the active [[Geopsy: Signal Viewer|signal viewer]] by a constant value. This is especially useful for data conversion from counts to velocity or acceleration, for instance.
+'''Multiply''', reached from the [[Geopsy: Waveform menu|Waveform menu]], multiplies the signals in the active [[Geopsy: Signal Viewer|signal viewer]] by a constant value. This is especially useful for data conversion from counts to velocity or acceleration, for instance.
 By clicking on ''Multiply'', a pop-up window appears and lets the user enter the value of the multiplication factor.
 ''Multiply'' should not be used for [[Geopsy: Data Conversion|data conversion]].
-''Multiply'' modifies the [[Geopsy: Temporary Signal|temporary signals]] in the active viewer.
+''Multiply'' creates new [[Geopsy: Temporary Signal|temporary signals]] displayed in the active viewer.

@@ Line 1: / Line 1: @@
 '''Multiply''', reached from the [[Geopsy: Waveform Menu|Waveform menu]], multiplies the signals in the active [[Geopsy: Signal Viewer|signal viewer]] by a constant value. This is especially useful for data conversion from counts to velocity or acceleration, for instance.
-By clicking on Multiply, a pop-up window appears and lets the user enter the value of the multiplication factor.
+By clicking on ''Multiply'', a pop-up window appears and lets the user enter the value of the multiplication factor.
 ''Multiply'' should not be used for [[Geopsy: Data Conversion|data conversion]].
 ''Multiply'' modifies the [[Geopsy: Temporary Signal|temporary signals]] in the active viewer.

← Older revision		Revision as of 08:42, 9 March 2010
Line 1:		Line 1:
−	'''Multiply''', reached from the [[Geopsy: Waveform Menu\|Waveform menu]], multiplies the signals in the active [[Geopsy: Signal Viewer\|signal viewer]] by a constant value. This is especially useful for data conversion from counts to velocity or acceleration, for ~~example~~.	+	'''Multiply''', reached from the [[Geopsy: Waveform Menu\|Waveform menu]], multiplies the signals in the active [[Geopsy: Signal Viewer\|signal viewer]] by a constant value. This is especially useful for data conversion from counts to velocity or acceleration, for instance.
	By clicking on Multiply, a pop-up window appears and lets the user enter the value of the multiplication factor.		By clicking on Multiply, a pop-up window appears and lets the user enter the value of the multiplication factor.

@@ Line 5: / Line 5: @@
 ==Data Conversion==
-Currently, signals are not converted or corrected by the response file of the acquisition system when [[Geopsy: Import signal files|imported in Geopsy]]. "Multiply" is the only way to convert data from counts or volts delivered by the digitizer into velocity or acceleration. For a recording in velocity, the conversion factor C is computed as follows:
+Currently, signals are not converted or corrected by the response file of the acquisition system when [[Geopsy: Import signal files|imported in Geopsy]]. "Multiply" is the only way to convert data from counts or volts delivered by the digitizer into velocity or acceleration.
 <math>C[(m/s)/count]=\frac{StationConversion [V/count]}{Gain [-] . SensorSensitivity [V/(m/s)]  }</math>.
@@ Line 14: / Line 15: @@
 *Quanterra Q330 digitizer with Lennartz 5s sensor: <math>C=5.96047e-9 [(m/s)/count]</math>
 *Nanometrics Taurus digitizer with Kinemetrics Episensor accelerometer: <math>C=1.58946e-9 [(m/s^2)/count]</math>