FOR LOWïºFREQUENCY SEISMOMETRY - IRIS

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4.3. Test ProceduresTest procedures and the method of reporting test resultsshould consider the procedures and templates describedin ANSI (2003). Many of the sections are as applicable toseismometers as they are to accelerometers for inertial guidancesystems. The Albuquerque Seismological Laboratorydocumented their approach some years ago (Hutt, 1990),and it would be appropriate to review and update these writtenguidelines. A revision should consider all phases of testing,including development testing, design qualification testing,acceptance testing, operational testing, and post-installationtesting.4.4. Support and AccessTop-notch field facilities are not cheap. As national resourcesthey should be funded, not only for the manager’s parochialinterests, but also for use of the whole community— academicand commercial, national, and international. Thus, managersshould be accommodating to all potential users andprovide visitors a range of support. However, there must bean understanding of the limits of default support, and provisionmade for recharge to handle exceptionally long or arduousvisits.In general, open circulation of test results, including peerreviewpublication, is to be encouraged. However, vendorsmay have proprietary interests in test results, whether favorableor unfavorable, and these concerns about intellectualproperty (IP) will need to be respected.16
5. Partnerships Between Industryand Academia5.1. Historical BackgroundEffective partnerships between industry and academia havegiven Earth scientists their best instruments for low-frequencyseismology. The LaCoste-Romberg gravity meter, onwhich Earth’s free oscillations were first observed, grew froma graduate student thesis into a major geophysical corporation.The superconducting gravity meter was first developedin an academic department and later commercialized. Butthese two examples are decades old, and there are no recentinstances in the United States of connections between industryand academia for development of sensors suitable forlow-frequency seismology. This is not the case in Europe,where both the Guralp and Streckeisen companies have theirroots in university research.By far the most significant work in the United States overthe last half century on seismic sensors has been directed towardsystems for nuclear test detection. These were superbfor the need, and some systems or sub-systems developedfor nuclear monitoring have been deployed in the GlobalSeismographic Network. However, it is clear that these sensorsare not the best at the lowest frequencies. Furthermore,test-detection programs ceased developing new sensors morethan a decade ago.We believe the collaboration in the United States betweenindustry and academia for developing novel seismicsensors needs to be revitalized. This collaboration shouldbe shaped by realizing that exciting discoveries in low-frequencyseismology are more likely to come from large-scaledeployments of quantities of sensors than from highly sophisticated,but one-off systems. Industry, rather than theacademic research department, is the place to manufacturecommodity instruments.Researchers will get the instruments they need only ifeach side understands the requirements and limitations ofthe other. Industry must see an opportunity for profit. Academicsseek new knowledge, and almost always, their science-basedresearch is advanced by new instrumentation. Adeep understanding of the capabilities and limitations of instrumentationis fundamental to progress.5.2. What is an AppropriateRelationship?The market for long-period sensors is so small, and the unitsthat can be sold per year so limited, that industry can not beexpected to perform the necessary R&D for this communityon speculation. This situation does not apply for instrumentsin higher-frequency bands. In the oil business, the marketcan justify investment of many millions by sensor manufacturers,because, if successful, they will sell many thousands ofunits a year. In the smaller community of body wave seismology,it is also true that manufacturers have been able to fundresearch and development internally, even for sales of a fewhundred units a year or less.In the low-frequency seismology community, we generallyrequire quantities of a few score, at most, to be deliveredover many years. This combination of market size and productionrate means that our most important task is for industryand academia to work together to obtain the R&D fundsnecessary for progress.For some years there has been the hope that an instrumenttargeted to the higher-frequency market (frequencies> .01 Hz, say) would, almost as a side effect, have adequateperformance at the very lowest frequencies. Experience hasshown that this is generally not the case. The very best lowfrequencysensors are purposely designed. Thus:• Superior low-frequency seismic sensors are not likely tobe developed from R&D funds internally generated bymanufacturers.Thus, the foundation of the academic/industrial partnershipwill continue to be an academic evangelist with a compellingscience question whose answer requires state-of-the artinstrumentation. This person is someone who is obsessedby the science, is successful at fund raising, sits on the rightcommittees, and is viewed as a dynamo in their field. They17
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Page 5 and 6: ContentsExecutive Summary .........
Page 7 and 8: Executive SummaryFor nearly a quart
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Page 17 and 18: Table 2. GSN Sensor Requirements.Dy
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Page 25 and 26: Benefit to academe:• Endowment.
Page 27 and 28: 7. AcknowledgementsWe would like to
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Page 32: THE INCORPORATED RESEARCHINSTITUTIO

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