Guralp Systems Scream User Manual

Page 132

Scream! 4.5

3. Whilst holding down the shift-key (

), drag a box across

the streams. The selected data will be highlighted.
Alternatively, drag with

to select two streams (see “Paused

4. When you release the mouse button, a menu will pop up

showing the extensions available.

5. Click on the name of the extension you want to run. The

standard Scream! Package (depending on installer) includes a

number of useful extensions:

ART Analysis Package : Güralp Systems' suite of tools for strong

motion analysis. See the separate ART documentation
(MAN-SWA-0003) for full details of this package.

PSD in Velocity Units and PSD in Acceleration Units : These
extensions produce instant power spectral density plots of the

selected time series.

Sine Wave Calibration, Step Calibration and Broadband Noise
Calibration : These extensions help you to calibrate sensors

using an input sinusoidal, step or pseudo-random noise signal.
These signals can be generated by Güralp Systems DM24 and

CD24 digitisers, allowing you to calibrate sensors quickly and
easily.

Relative Orientation : This extension applies the
Güralp-Blacknest correlation method to determine the

orientation of an instrument (usually a borehole instrument). It
uses coherence techniques to estimate the angle between the

horizontal components of two sensors, where one is rotated
with respect to the other.

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