Duration - Revision history

Scottcal at 21:26, 8 October 2015

2015-10-08T21:26:26Z

Scottcal at 21:26, 8 October 2015

2015-10-08T21:26:08Z

Scottcal at 19:49, 8 October 2015

2015-10-08T19:49:45Z

Scottcal at 19:49, 8 October 2015

2015-10-08T19:49:03Z

Scottcal: /* Verification */

2015-10-06T22:31:16Z

Verification

Scottcal: /* Verification */

2015-10-06T22:31:08Z

Verification

Scottcal at 22:30, 6 October 2015

2015-10-06T22:30:58Z

Maechlin at 20:19, 6 October 2015

2015-10-06T20:19:07Z

Maechlin: /* Related Entries */

2015-10-06T20:17:50Z

Related Entries

Maechlin: Created page with 'Duration calculations are used to define the duration of shaking from an earthquake. Currently, the BBP has 2 codes for calculating Arias intensity and then significant duration…'

2015-10-06T20:17:35Z

Created page with 'Duration calculations are used to define the duration of shaking from an earthquake. Currently, the BBP has 2 codes for calculating Arias intensity and then significant duration…'

New page

Duration calculations are used to define the duration of shaking from an earthquake.

Currently, the BBP has 2 codes for calculating Arias intensity and then significant duration for acceleration seismograms. One is by CG and works on PEER-format seismograms; the other is by SR and is a more general function which takes an array of floats (the seismogram) as input. Both are short Python codes, about 8 lines of code. The BBP does not have any codes to calculate the energy integral or the significant duration for velocity seismograms, or the CAV.

The CyberShake platform prefers a C implementation. If we try to use a Python implementation from the BBP, we either have to call Python from C, or invoke a separate job to calculate the durations. In our design, we would prefer to just call a C function from the already-existing post-processing code, since it will mean we don't have to add another job for each rupture, and we don't have to read the seismogram in from disk an extra time. Additionally, if we use the BBP code, we would have to add an implementation of the energy integral and the CAV anyway. Since the calculation is very simple, it also seems less important to use the identical code.

We plan write a CyberShake C implementation and use SR implementation in the BBP to verify the CyberShake C duration code. Additionally, we plan to store 4 significant durations in the database (acceleration and velocity for 5/75 and 5/95), but the other values (the Arias duration, the energy integral, the CAV, and the 20/80 significant durations) will only exist in output files, much like how we produce PSA and RotD at periods we don't insert into the database.

== Verification ==

== Related Entries ==
*[[CyberShake]]
*[[BBP]]

@@ Line 17: / Line 17: @@
 ! C, velocity duration 5-95%
 |-
-| [http://http://hypocenter.usc.edu/research/cybershake/duration_seismograms/Seismogram_PAS_3878_280_0.grm Seismogram_PAS_3878_280_0.grm], RV 0
+| [http://hypocenter.usc.edu/research/cybershake/duration_seismograms/Seismogram_PAS_3878_280_0.grm Seismogram_PAS_3878_280_0.grm], RV 0
 | 15.650000
 | 15.650001
@@ Line 23: / Line 23: @@
 | 22.800001
 |-
-| [http://http://hypocenter.usc.edu/research/cybershake/duration_seismograms/Seismogram_PAS_3878_239_58.grm Seismogram_PAS_3878_239_58.grm], RV 36
+| [http://hypocenter.usc.edu/research/cybershake/duration_seismograms/Seismogram_PAS_3878_239_58.grm Seismogram_PAS_3878_239_58.grm], RV 36
 | 25.900000
 | 25.900000
@@ Line 29: / Line 29: @@
 | 64.950005
 |-
-| [http://http://hypocenter.usc.edu/research/cybershake/duration_seismograms/Seismogram_PAS_3878_128_1296.grm Seismogram_PAS_3878_128_1296.grm], RV 510
+| [http://hypocenter.usc.edu/research/cybershake/duration_seismograms/Seismogram_PAS_3878_128_1296.grm Seismogram_PAS_3878_128_1296.grm], RV 510
 | 11.950000
 | 11.950000

@@ Line 17: / Line 17: @@
 ! C, velocity duration 5-95%
 |-
-| Seismogram_PAS_3878_280_0.grm, RV 0
+| [http://http://hypocenter.usc.edu/research/cybershake/duration_seismograms/Seismogram_PAS_3878_280_0.grm Seismogram_PAS_3878_280_0.grm], RV 0
 | 15.650000
 | 15.650001
@@ Line 23: / Line 23: @@
 | 22.800001
 |-
-| Seismogram_PAS_3878_239_58.grm, RV 36
+| [http://http://hypocenter.usc.edu/research/cybershake/duration_seismograms/Seismogram_PAS_3878_239_58.grm Seismogram_PAS_3878_239_58.grm], RV 36
 | 25.900000
 | 25.900000
@@ Line 29: / Line 29: @@
 | 64.950005
 |-
-| Seismogram_PAS_3878_128_1296.grm, RV 510
+| [http://http://hypocenter.usc.edu/research/cybershake/duration_seismograms/Seismogram_PAS_3878_128_1296.grm Seismogram_PAS_3878_128_1296.grm], RV 510
 | 11.950000
 | 11.950000

@@ Line 12: / Line 12: @@
 {|  border="1"
 ! Input seismogram
-! Python, significant duration (velocity) 5-75
+! Python, velocity duration 5-75%
-! C, significant duration (velocity) 5-75
+! C, velocity duration 5-75%
-! Python, significant duration (velocity) 5-95
+! Python, velocity duration 5-95%
-! C, significant duration (velocity) 5-95
+! C, velocity duration 5-95%
 |-
 | Seismogram_PAS_3878_280_0.grm, RV 0

@@ Line 12: / Line 12: @@
 {|  border="1"
 ! Input seismogram
-! Python Dv 5-75
+! Python, significant duration (velocity) 5-75
-! C Dv 5-75
+! C, significant duration (velocity) 5-75
-! Python Dv 5-95
+! Python, significant duration (velocity) 5-95
-! C Dv 5-95
+! C, significant duration (velocity) 5-95
 |-
 | Seismogram_PAS_3878_280_0.grm, RV 0

@@ Line 10: / Line 10: @@
 We expect to have two implementations of Duration (in C and Python). For the common output types, we will input the same seismogram to both methods and show that the methods produce equivalent results. For input, we use CyberShake seismograms.  The Python implementation is taken from rzz2015.py, while the C implementation is derived from Matlab code provided by Nenad Bijelic.  These verification tests are documented here:
-{ border="1" |
+{|  border="1"
 ! Input seismogram
 ! Python Dv 5-75

@@ Line 8: / Line 8: @@
 == Verification ==
-We expect to have two implementations of Duration (in C and Python). For the common output types, we will input the same seismogram to both methods and show that the methods produce equivalent results. These verification tests are documented here:
+We expect to have two implementations of Duration (in C and Python). For the common output types, we will input the same seismogram to both methods and show that the methods produce equivalent results. For input, we use CyberShake seismograms.  The Python implementation is taken from rzz2015.py, while the C implementation is derived from Matlab code provided by Nenad Bijelic.  These verification tests are documented here:
 == Related Entries ==
 *[[CyberShake]]
 *[[Broadband Platform]]

← Older revision		Revision as of 20:19, 6 October 2015
Line 8:		Line 8:

	== Verification ==		== Verification ==
		+	We expect to have two implementations of Duration (in C and Python). For the common output types, we will input the same seismogram to both methods and show that the methods produce equivalent results. These verification tests are documented here: