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Preliminary Investigation into Temporal Changes in Acoustic Scattering from the Seafloor.

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Preliminary Investigation into Temporal Changes in Acoustic Scattering from the Seafloor./
作者:	Catoire, Matthew.
面頁冊數:	1 online resource (128 pages)
附註:	Source: Masters Abstracts International, Volume: 83-01.
Contained By:	Masters Abstracts International83-01.
標題:	Acoustics. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=28411349click for full text (PQDT)
ISBN:	9798516963513

Preliminary Investigation into Temporal Changes in Acoustic Scattering from the Seafloor.
Catoire, Matthew.

Preliminary Investigation into Temporal Changes in Acoustic Scattering from the Seafloor. - 1 online resource (128 pages)

Source: Masters Abstracts International, Volume: 83-01.

Thesis (M.S.)--University of New Hampshire, 2021.

Includes bibliographical references

When examining the acoustic response of the seafloor, scattering strength is assumed to be temporally invariant. However, the state of the seafloor in terms of roughness and sediment heterogeneity is not temporally invariant. Changes in both seafloor roughness and sediment heterogeneity are known to correlate with changes in scattering strength. This thesis is a preliminary investigation into the temporal variability of scattering strength. The data for this thesis was collected in three separate experiments at two different sites: 24-30September, 2020 offshore of New Castle Island; 02-23 October, 2020 offshore of New Castle Island; and 27 October, 2020-12 November, 2020 offshore of Star Island. Analysis of the data from 02-23 October revealed the New Castle Island site to have a range of scattering strengths of at least 5 dB across all frequencies. Lower grazing angles have ranges in excess of 10 dB. The Star Island data from 27 October-12 November and the New Castle Island data from24-30 September did not show as much variability. The variability for both data sets was frequently within an uncertainty of ±1.25 dB. This does not mean there was no variability, as changes in scattering strength of 3-4 dB over time scales of days were observed in both data sets. Causes for the variability in scattering strength and reasons for the differences in variability among the experiments were examined, but definitive conclusions were not reached. The work described by this thesis provides the groundwork for more detailed and extensive experiments that will be performed over the next two years.

Electronic reproduction.
Ann Arbor, Mich. :
ProQuest,
2023

Mode of access: World Wide Web

ISBN: 9798516963513Subjects--Topical Terms:

879105
Acoustics.
Subjects--Index Terms:

Temporal changesIndex Terms--Genre/Form:

542853
Electronic books.

Preliminary Investigation into Temporal Changes in Acoustic Scattering from the Seafloor.
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245 1 0 $a Preliminary Investigation into Temporal Changes in Acoustic Scattering from the Seafloor.
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500 $a Source: Masters Abstracts International, Volume: 83-01.
500 $a Advisor: Lyons, Anthony; Foster, Diane.
502 $a Thesis (M.S.)--University of New Hampshire, 2021.
504 $a Includes bibliographical references
520 $a When examining the acoustic response of the seafloor, scattering strength is assumed to be temporally invariant. However, the state of the seafloor in terms of roughness and sediment heterogeneity is not temporally invariant. Changes in both seafloor roughness and sediment heterogeneity are known to correlate with changes in scattering strength. This thesis is a preliminary investigation into the temporal variability of scattering strength. The data for this thesis was collected in three separate experiments at two different sites: 24-30September, 2020 offshore of New Castle Island; 02-23 October, 2020 offshore of New Castle Island; and 27 October, 2020-12 November, 2020 offshore of Star Island. Analysis of the data from 02-23 October revealed the New Castle Island site to have a range of scattering strengths of at least 5 dB across all frequencies. Lower grazing angles have ranges in excess of 10 dB. The Star Island data from 27 October-12 November and the New Castle Island data from24-30 September did not show as much variability. The variability for both data sets was frequently within an uncertainty of ±1.25 dB. This does not mean there was no variability, as changes in scattering strength of 3-4 dB over time scales of days were observed in both data sets. Causes for the variability in scattering strength and reasons for the differences in variability among the experiments were examined, but definitive conclusions were not reached. The work described by this thesis provides the groundwork for more detailed and extensive experiments that will be performed over the next two years.
533 $a Electronic reproduction. $b Ann Arbor, Mich. : $c ProQuest, $d 2023
538 $a Mode of access: World Wide Web
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650 4 $a Ocean engineering. $3 660731
650 4 $a Standard deviation. $3 3560390
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650 4 $a Sound waves. $3 3561055
650 4 $a Floods. $3 549458
650 4 $a Experiments. $3 525909
650 4 $a Normal distribution. $3 3561025
650 4 $a Sediment transport. $3 555890
650 4 $a Energy. $3 876794
650 4 $a Grain size. $3 3682362
650 4 $a Offshore. $3 3681420
650 4 $a Physical properties. $3 3564184
650 4 $a Fluid mechanics. $3 528155
650 4 $a Biological activity. $3 3699913
653 $a Temporal changes
653 $a Acoustic scattering
653 $a Seafloor
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690 $a 0547
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690 $a 0204
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