NAME

dbwfmeas - make waveform measurments from a database

SYNOPSIS


dbwfmeas [-p parameter_file] [-v] [-outrecno] [-exitonerror]
         {detection|arrival|time staexpr chanexpr tstart twin} dbin [dbout]

DESCRIPTION

dbwfmeas is a program that reads waveform data from a database, performs some kinds of waveform measurement and writes out the results of the measurements to the database.

OPTIONS

PROGRAM PARAMETER FILE

The dbwfmeas parameter file contains information that defines the particular measurements to be made. Currently there are seven recognized measurement types;

An example dbwfmeas parameter file is as follows:


#
#	dbwfmeas.pf contains the parameters for making waveform
#	measurements
#

global_defaults &Arr{
    remove_mean      yes    # Remove mean from waveform data
                            #   after filtering before making
                            #   measurements
    use_det_filter   yes    # Use filter parameters from input
                            #   detection rows instead of
                            #   from this parameter file
    calib_from_calibration  no # Should calib values come
                               #   from the database calibration
                               #   table (yes) or directly from
                               #   the waveform wfdisc rows (no)?
}

measurements &Tbl{
    &Arr{
        type     peakd       # peak displacement measurements
        tlead    10.0        # lead time window in seconds
        tlag     10.0        # lag time window in seconds
        tpad     10.0        # time pad in seconds to remove
                             #   filter transients
        filter   BW 1. 5 0 0 # pre-filter
        channels &Tbl{       # channels to process
        #    sta_expr    chan_expr      [wfchan_expr]
            .*           HL.
        }
    }
    &Arr{
        type     spec        # make Power Spectral Density estimate
        twin     10.0        # taper window length
        tdur     1000.0      # duration of time series to use
        offset   10.0        # offset in seconds between windows
        taper    gaussian    # taper type (only gaussian at present)
        rsptype  V           # units of output - D = displacement
                             #                   V = velocity
                             #                   A = acceleration
                             #                   C = counts
        channels &Tbl{       # channels to process
        #    sta_expr    chan_expr
            .*           [BHE]..
        }
    }
    &Arr{
        type	peakv		# peak ground velocity measurement
        lead	10.0		# lead time window in seconds
        lag	20.0		# lag time window in seconds
        pad	10.0		# time pad in seconds to remove
                                #   filter transients
        ptype   vector
        oype    wfmgme          # write output to wfgme rows
        channels &Tbl{		# channels to process
#               sta_expr chan_expr wfchan_expr
                .*       HGZ       HG.
        }
    }
    &Arr{
        type	peaka		# peak ground acceleration measurement
        lead	10.0		# lead time window in seconds
        lag	20.0		# lag time window in seconds
        pad	10.0		# time pad in seconds to remove
                                #   filter transients
        ptype   vector
        oype    wfmgme          # write output to wfgme rows
        channels &Tbl{		# channels to process
#               sta_expr chan_expr wfchan_expr
                .*       HGZ       HG.
        }
    }
    &Arr{
        type	peakwa		# peak Wood-Anderson measurement
        lead	10.0		# lead time window in seconds
        lag	20.0		# lag time window in seconds
        pad	10.0		# time pad in seconds to remove
                                #   filter transients
        ptype   biggest
        oype    wfmgme_flush    # write output to wfgme rows and flush
        channels &Tbl{		# channels to process
#               sta_expr chan_expr wfchan_expr
                .*       HGZ       HG[NE]
        }
    }
}

The parameter file is broken into two main sections; the global_defaults array, which is used to define the values of parameters to be used as global default values, and the measurements table, which contains unnamed parameter arrays corresponding to the different measurements that are to be made. The particular measurements are made in the order in which they are specified in the measurements table. Each of the measurement arrays contain parameters for that measurement and a table of channels to be processed. Any missing parameters from a measurement array will be taken from the global defaults array. Each of the measurement arrays must contain a type parameter, which defines the measurement type, and a channels table, which lists the station-channels to be processed. Each row in the channels table must contain either a simple character string with two fields, the first a sta expression and the second a chan expression, or another unnamed parameter array which must contain at least a sta_expr parameter and a chan_expr parameter. These unnamed arrays within the channels table may also contain any of the other parameters for that measurement type, and any such parameters over-ride the measurement parameters for the stations and channels that match that sta_expr and chan_expr. When input channels match more than one row in the channels table, then the last row which matches is used.

peak measurement arrays are used to set up data channels and parameters for making peak waveform amplitude measurements. The peak measurements are made in units that are natural to the data, nm/sec for velocity sensor data, milli-Gs (mg) for acceleration sensor data. The sensor type is obtained from the database, as specified through the dbname command line argument. Peak waveform measurements are made for both a time window immediately after the detection/arrival time, refered to as a signal peak value, and for a time window immediately prior to the detection/arrival time, refered to as a noise peak value. The signal peak value is written into the val1 field of the output wfmeas row and the noise peak value is written into the val2 field. The time corresponding to the signal peak value is written into the tmeas field. The parameters for peak measurements are defined below.

peaka measurements are used to set up data channels and parameters for making peak ground acceleration measurements. The peak acceleration measurements are made in milli-Gs (mg) for all sensor types. Data from velocity sensors are automatically differentiated to convert to acceleration. All other information and processing are as for the peak measurement type. Note that instrument deconvolution is not performed here, only simple differentiation.

peakv measurements are used to set up data channels and parameters for making peak ground velocity measurements. The peak velocity measurements are made in nm/sec for all sensor types. Data from acceleration sensors are automatically integrated to convert to velocity. All other information and processing are as for the peak measurement type. Note that instrument deconvolution is not performed here, only simple integration.

peakd measurements are used to set up data channels and parameters for making peak ground displacement measurements. The peak displacement measurements are made in nm for all sensor types. Data from acceleration sensors are automatically integrated twice to convert to displacement. Data from velocity sensors are automatically integrated once to convert to displacement. All other information and processing are as for the peak measurement type. Note that instrument deconvolution is not performed here, only simple integration.

peakwa measurements are used to set up data channels and parameters for making peak equivalent Wood-Anderson measurements. The peak Wood-Anderson measurements are made in equivalent mm of Wood-Anderson drum recorder for all sensor types. Data from sensors are automatically integrated to convert to displacement and then forward filtered with a Wood-Anderson instrument filter. All other information and processing are as for the peak measurement type. Note that instrument deconvolution is not performed here, only simple integration and Wood-Anderson filtering.

AUTHOR

Danny Harvey, Frank Vernon
Boulder Real Time Technologies, Inc.

Table of Contents
Antelope Release 4.7 Linux 2.4.19-4GB 2005-12-21
Boulder Real Time Technologies, Inc For more information, contact support@brtt.com