Difference between revisions of "Geopsy: H/V and Spectrum Toolboxes: Time Tab"
(New page: == Use == This toolbox tab contains the parameters to select the part of the signal used for H/V or Spectrum processing on which window sele...) |
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== Time window area == | == Time window area == | ||
| − | Short-duration disturbances of the signal can be avoided during [[H/V_spectral_ratio|H/V]] or [[Spectral_amplitudes|Spectrum]] processing by using an anti-trigger window selection to remove the transients. The objective is to keep the most stationary parts of ambient vibrations, and to avoid the transients often associated with specific sources (footsteps, close traffic). This objective is exactly the opposite of the usual goal of seismologists who want to detect signals, and have developed specific trigger algorithm to track the unusual transients possibly indicating the satrt of an earthquake. Here an anti-trigger algorithm is used, which is exactly the opposite: it detects transients but it tries to avoid them. For more information on this topic it it suggested to consult <ref>Guidelines for the implementation of the H/V spectral ratio technique on ambient vibrations measurements, processing and interpretation, [http://SESAME-FP5.obs.ujf-grenoble.fr], 62 pages, April 2005</ref>. | + | Short-duration disturbances of the signal can be avoided during [[H/V_spectral_ratio|H/V]] or [[Spectral_amplitudes|Spectrum]] processing by using an anti-trigger window selection to remove the transients. The objective is to keep the most stationary parts of ambient vibrations, and to avoid the transients often associated with specific sources (footsteps, close traffic). This objective is exactly the opposite of the usual goal of seismologists who want to detect signals, and have developed specific trigger algorithm to track the unusual transients possibly indicating the satrt of an earthquake. Here an anti-trigger algorithm is used, which is exactly the opposite: it detects transients but it tries to avoid them. For more information on this topic it it suggested to consult the SESAME user guidelines <ref>Guidelines for the implementation of the H/V spectral ratio technique on ambient vibrations measurements, processing and interpretation, [http://SESAME-FP5.obs.ujf-grenoble.fr], 62 pages, April 2005</ref>. |
[[Image:HV_SPEC_toolb_time_global.png|thumb|right|300px]] | [[Image:HV_SPEC_toolb_time_global.png|thumb|right|300px]] | ||
Revision as of 11:02, 10 March 2010
Use
This toolbox tab contains the parameters to select the part of the signal used for H/V or Spectrum processing on which window selection is performed. The two series of paramaters are described in two areas:
- the global time range area
- the time windows area
A third area gives information on the number of selected windows obtained after applying to the signal the parameters of the two precedent areas.
At the very bottom two buttons indicate wether to load parameters from previouly processed data or to start signal processing signal processing.
Global time range area
Select the portion of the signal that will be processed (learn more).
Time window area
Short-duration disturbances of the signal can be avoided during H/V or Spectrum processing by using an anti-trigger window selection to remove the transients. The objective is to keep the most stationary parts of ambient vibrations, and to avoid the transients often associated with specific sources (footsteps, close traffic). This objective is exactly the opposite of the usual goal of seismologists who want to detect signals, and have developed specific trigger algorithm to track the unusual transients possibly indicating the satrt of an earthquake. Here an anti-trigger algorithm is used, which is exactly the opposite: it detects transients but it tries to avoid them. For more information on this topic it it suggested to consult the SESAME user guidelines [1].
