_REVISION - C1996083 ‎(2)‎

• Permit No: C1996083
• IBM Index Class Name: REVISION
• Doc Name: Seismic Event Data Acquistition and Processing Distribition and Coordination Across PC-Based Network
• Type & Sequence: PR10
• Media Type: D
• Archive: No

FACTORS GUIDING SYSTEM DESIGN
Besides low cost, reliability, and flexibility were important considerations in system design. The
expense and downtime associated with timely repair and/or replacement of custom data
acquisition and processing hardware, as experienced with some previous USBM systems, was to
be avoided. Mass-produced personal computers (PC's) and commercial multichannel analog-to-
digital (A/D)converters minimize capital expenditures and repair costs and provide a high degree
of reliability.
Other factors influencing this design effort were distributed processing, automation, low-cost
installation,and availability of software.
A distributed network of data collection computers(Figure 1)was selected rather than a single
centralized system for several reasons.
(1) A distributed system avoids single-point failures that result in complete loss of monitoring
coverage.
(2) Networking several small-scale autonomous seismic networks that share data avoids the
installation of an expensive and difficult to maintain network of long cables.
(3) In many, if not most, mining situations, it is extremely difficult to completely surround the
area of interest with sensors from accessible underground workings alone. Encircling the area of
interest with sensors is a basic requirement for locating seismic events accurately. Drilling
boreholes for sensor installation is an expensive and difficult option not generally available to
relatively short-term NIOSH research studies and is not practical for high-production mining
environments that rapidly sweep through large areas. The use of several smaller autonomous
arrays distributed on the surface, underground, in surface boreholes, in neighboring mines, on
different underground levels, etc., can surround the area of interest and help provide the needed
three-dimensional coverage.
(4) Delivery of summary processed results to mine personnel stationed underground and on the
surface was an additional constraint satisfied by a distributed data acquisition and processing
scheme.
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Portable GPs
Seismic array(s) timing
array-1 GPS .�
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Distributed Seismic Data
Collection and Processing Processor-n
Seismic Seismic
_ array-2 array-n
(Processor-
Figure 1. PC-network-based seismic acquisition and
processing system.