Infrasound Data Processing at Geoscience Australia David J

Infrasound Data Processing at Geoscience Australia David J Brown ITW 2007, Tokyo

Overview • Current State of the automatic infrasound processing system operating at GA. – signal detection – source location – job queuing – example – summary ITW 2007, Tokyo

Signal Detection Parameter Space, Image Space, S Hough Transform ITW 2007, Tokyo P

Source location Initial state M=0. 24 Iteration one M=0. 24 The Neighbourhood algorithm: minimise the misfit • distribute points in computational domain Iteration two M=0. 004 Iteration three M=0. 004 • find the region about each point that is closer to that point than any other (voronoi cell) • distribute the same number of points randomly in the first few voronoi cells with the smallest values of misfit ITW 2007, Tokyo

Source location – access travel-time data using lat/lon information via a minimal perfect hash Unique 16 -digit string (24. 0948, 63. 4349) (23. 8670, 76. 7989) (35. 2644, 75. 0000) 24. 0948. 063. 4349 23. 8670. 076. 7989 35. 2644. 075. 0000 data file generated for each station and stored as a shared memory segment on the host travel-time and azimuthal deviation information assuming each grid point is a source location and acoustic propagation for some prescribed climatological model is determined and stored in a vector accessible using an index that is a hash of the lat/lon string ITW 2007, Tokyo

job queuing • main operation controlled by the Infer Listener GUI – an instance will need to run on each host that wants to process data colour panel shows state of processing for each hour for each station Start/Stop button to toggle operation of the current instance. Stop All button to stop operation of all instances Infer Listener is constantly trawling the infer noticeboard looking for jobs to run. Currently processing jobs are displayed in this panel ITW 2007, Tokyo

job queuing • main operation controlled by the Infer Listener GUI – an instance will need to run on each host that wants to process data Infer Listener is constantly trawling the infer noticeboard looking for jobs to run. Currently processing jobs are displayed in this panel ITW 2007, Tokyo

job queuing noticeboard job 1. x job 2. x job 3. x job 4. x arg 1 arg 1 arg 3 arg 4 arg 1 arg 3 arg 4 - date s m m s 300 60 listener grabs job from noticeboard - hostname 3 listener hostname 1 listener updates noticeboard forks listener hostname 2 hostname 1 listener child pid noticeboard job 1. x job 2. x job 3. x job 4. x arg 1 arg 2 arg 3 arg 4 arg 2 arg 3 arg 4 ITW 2007, Tokyo hostname 1 hostname 2 hostname 3 hostname 1 date s m m s 300 60 pid=1234 pid=2345 pid=3456 pid=4567

job queuing hostname 3 listener updates noticeboard if job is re-entrant listener hostname 1 listener constantly checking for defunct child processes (i. e. zombies) hostname 2 listener noticeboard job 2. x arg 1 arg 2 arg 3 job 3. x arg 1 arg 2 ITW 2007, Tokyo - date m m 300 60 -

job queuing • Infer Noticeboard – starting jobs list INFER_LISTNER/bin/check_alert_type=Volcano Region=‘New Britain’ sta_list IS 04 IS 05 IS 07 INFER_LISTNER/bin/check_alert_type=Volcano Region=‘Java’ sta_list IS 04 IS 05 IS 07 2 INFER_LISTNER/bin/check_alert_type=Volcano Region=‘Lesser Sunda’ sta_list IS 04 IS 05 IS 07 INFER_LISTNER/bin/check_alert_type=Standard Region=‘All’ sta_list IS 04 IS 05 IS 07 5 INFER_LISTNER/bin/check_event INFER_LISTNER/bin/infer_det 6 INFER_LISTNER/bin/infer_loc sta_list IS 04 IS 05 IS 07 INFER_LISTNER/bin/tickle_man INFER_LISTNER/bin/remove_logs ITW 2007, Tokyo 8 9 7 1 4 3

job queuing • Infer Noticeboard – starting jobs list 1 2 3 checks the arrival table for significant signals from a volcanic region for the sta list INFER_LISTNER/bin/check_alert_type=Volcano Region=‘Java’ sta_list IS 04 IS 05 IS 07 4 checks the arrival table for significant signals from any region INFER_LISTNER/bin/check_alert_type=Standard Region=‘All’ sta_list IS 04 IS 05 IS 07 ITW 2007, Tokyo

job queuing • regions file Alert Name: Volcano ========================= Region: New Britain lat lon Location: name: Manam -4. 10 145. 06 name: Rabaul -4. 271 152. 203 name: Langila -5. 525 148. 42 name: Garbuna_Group -5. 45 150. 03 name: Pago -5. 58 150. 52 name: Ulawun -5. 05 151. 33 name: Lolabau -4. 92 151. 158 Region: Location: name: Java Region: Location: name: Lesser Sunda Merapi Ruang Kelut Batu_Tara Soputan -7. 542 -8. 125 -7. 93 -7. 792 1. 108 110. 442 114. 042 112. 308 123. 579 124. 730 Alert Name: Standard ========================= Region: All lat lon Location: name: All - ITW 2007, Tokyo

job queuing • alert email issued – alert name + region name in subject heading Volcano Alert: New Britain ========================= Station: IS 04 Azimuth: 56. 4 Frequency: 1. 0 Time(UTC): 2007304 18: 38: 23 Fstat: 24. 8 Duration: 320. 0 Arid: 37829 ITW 2007, Tokyo

job queuing • Infer Noticeboard – starting jobs list 5 checks the origin table formed events+sends email alert INFER_LISTNER/bin/check_event 6 Infrasonic Event: ========================= Lat: -22. 1459 Lon: 134. 5100 Time(UTC): 2007304 05: 22: 18 Ndef: 3 checks the wfdisc table for unprocessed data, places entries onto noticeboard to initiate detector INFER_LISTNER/bin/infer_det ITW 2007, Tokyo

job queuing • Infer Noticeboard – starting jobs list 7 queues consecutive four hour intervals for location for stations in the sta_list INFER_LISTNER/bin/infer_loc sta_list IS 04 IS 05 IS 07 8 tickle shared memory segment used in source location if non-constant velocity model used INFER_LISTNER/bin/tickle_man 9 remove processing log files INFER_LISTNER/bin/remove_logs ITW 2007, Tokyo

job queuing • NFS atomic-level file-locking (discretionary) noticeboard hostname 1 listener hostname 2 listener ITW 2007, Tokyo hostname 4 logfile Oracle • arrival • detection • infra_features • site • wfdisc • lastid • affiliation • origin listener hostname 3 listener

job queuing: • software design – no commercial software or expert knowledge to install – standard languages • ANSI-C • python • fortran – free-ware • FFTW http: //www. fftw. org/ • Oracle 10 g. XE http: //www. oracle. com/technology/software/products/ database/xe/htdocs/102 xelinsoft. html • python 2. 4, Pmw http: //www. python. org/ • NA http: //rses. anu. edu. au/~malcolm/na/na. html • Lock. File http: //mail. python. org/pipermail/mailman-developers/ 2000 -April/006657. html ITW 2007, Tokyo http: //pmw. sourceforge. net/

Example: The Taree Bolide, December 06, 2004 IS 07 125. 5 deg 19: 24: 08 IS 05 23. 8 deg 18: 27: 48 ITW 2007, Tokyo Large explosion woke residents along northern NSW coast Significant acoustic signals recorded on IS 05, IS 07

Example: The Taree Bolide, December 06, 2004 wfdisc data for 7 hours known to contain signals is loaded into Oracle db Listener ready to start ITW 2007, Tokyo

Example: The Taree Bolide, December 06, 2004 • infer_det has run and has queued all hours for processing. • Alert checking code continually being re-loaded. • each instance is limited to two concurrent processes. ITW 2007, Tokyo

Example: The Taree Bolide, December 06, 2004 • after some time 5 hours of data have successfully passed detection, one hour is currently processing and one hour is queued for processing • check alert has run and found several significant signals: • IS 07 125. 5 deg 2. 0 Hz • IS 05 23. 8 deg 2. 0 Hz • IS 05 110. 0 deg 0. 06 Hz • IS 05 125. 0 deg. 0. 06 Hz Infrasound Automatic Alert ===================== Station: IS 05 Azimuth: 23. 8 Frequency: 2. 0 Time(UTC): 2007309 18: 27: 48 Fstat: 24. 8 Duration: 60. 0 Arid: 2010 ITW 2007, Tokyo

Example: The Taree Bolide, December 06, 2004 • all hours have successfully passed detection and infer_loc has queued them for location • needs 4 consecutive hours that have passed detection ITW 2007, Tokyo

Example: The Taree Bolide, December 06, 2004 • processing complete: • one event formed and check_event has generated email Infrasonic Event: ===================== Lat: -30. 6793 Lon: 153. 5019 Time(UTC): 2007309 17: 11: 07 Ndef: 2 ITW 2007, Tokyo

Summary • Purpose of the infrasound processing system is to provide non-expert users: – a facility for detecting significant acoustic signals in IMS array data – an alert via email for significant signals – an estimate of when and where the event occurred for multiple station recordings • Ease of installation and use: – no software engineering knowledge required or a necessity to resort to commercial software ITW 2007, Tokyo

Summary • Automatic infrasound processing system is maturing – signal detection is rugged • population of arrival, detection and infra_features table is reliable • need to incorporate uncertainty estimatefor az+time – source location process is maturing • occasionally NA location algorithm gets trapped in local minima • conflict resolution in the association phase needs further testing • need to provide uncertainty in location ITW 2007, Tokyo

Summary • Automatic infrasound processing system is maturing – python queuing code works in general • a few idiosyncrasies – possible in rare circumstances for two hosts to execute the same job. – need mechanism to restore lost jobs when host dies • need to add extra features to the GUI: – user selectable detector/locator parameter selection – waveform display – improved error reporting ITW 2007, Tokyo