東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back

Switch To: Labeled | MARC Mode | ISBD

Broadband Acoustical Scattering in C...

Kahn, Rachel E.,

Linked to FindBook

Google Book

Amazon

博客來

Broadband Acoustical Scattering in Coastal Environments: Application to Gelatinous Organisms and Gas Microbubbles /

Record Type:	Electronic resources : Monograph/item
Title/Author:	Broadband Acoustical Scattering in Coastal Environments: Application to Gelatinous Organisms and Gas Microbubbles // Rachel E Kahn.
Author:	Kahn, Rachel E.,
Description:	1 electronic resource (110 pages)
Notes:	Source: Dissertations Abstracts International, Volume: 86-05, Section: A.
Contained By:	Dissertations Abstracts International86-05A.
Subject:	Plankton. -
Online resource:	https://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=31652265
ISBN:	9798346395928

Broadband Acoustical Scattering in Coastal Environments: Application to Gelatinous Organisms and Gas Microbubbles /
Kahn, Rachel E.,

Broadband Acoustical Scattering in Coastal Environments: Application to Gelatinous Organisms and Gas Microbubbles /Rachel E Kahn. - 1 electronic resource (110 pages)

Source: Dissertations Abstracts International, Volume: 86-05, Section: A.

Broadband acoustical technology revolutionized our ability to explore, monitor, and operate in the ocean. While strides have been made in numerous physical and biological applications, there remain many standing scientific questions well suited to broadband approaches. Physics-based sound scattering models allow us to interpret and draw quantitative observations from measurements. Such models have been developed and used to assess the biomass of many types of marine organisms of ecological significance, but we lack rigorous scattering models for gelatinous organisms despite their possibly accounting for a significant proportion of global marine biomass. Additionally, acoustical techniques for characterizing microbubble populations have been established for decades, yet little is known about the spectral characteristics of dense microbubble clouds associated with estuarine tidal fronts. These bubbles facilitate air-sea gas exchange and could interfere with acoustical operations in coastal environments; however, the density and size distribution of the bubbles must be known to assess their impacts. This dissertation addresses these deficiencies in our application of broadband techniques. In Chapter 2, a sound scattering model for gelatinous organisms is developed based on the Distorted Wave Born Approximation. The 3-D model is applied to a species of scyphomedusa and verified with laboratory measurements of broadband backscattering from live individuals. The model predicts backscattering levels and broad spectral behavior within <2 dB. In Chapter 3, a towable instrument is developed for measuring broadband excess attenuation from bubbles from which the size distribution is inferred. The instrument is tested under breaking waves in a laboratory wave tank and then used to characterize the bubble size distribution in the Connecticut River tidal ebb plume front. In Chapter 4, broadband backscattering measurements from the Connecticut River front are used to infer the associated bubble size distribution. Spatial trends in the bubble size distribution are examined within the context of frontal kinematics. An observed disparity between the bubble size distribution measured with excess attenuation and volume backscattering is hypothesized to arise from a sampling bias caused by bubbles concentrated in the upper water column.

English

ISBN: 9798346395928Subjects--Topical Terms:

1299572
Plankton.

Broadband Acoustical Scattering in Coastal Environments: Application to Gelatinous Organisms and Gas Microbubbles /
LDR:03705nmm a22004093i 4500 001 2429260
005 20250430093610.5
006 m o d
007 cr|nu||||||||
008 261011s2024 miu||||||m |||||||eng d
020 $a 9798346395928
035 $a (MiAaPQD)AAI31652265
035 $a (MiAaPQD)MIT1721_1_153712
035 $a AAI31652265
040 $a MiAaPQD $b eng $c MiAaPQD $e rda
100 1 $a Kahn, Rachel E., $e author. $3 3817003
245 1 0 $a Broadband Acoustical Scattering in Coastal Environments: Application to Gelatinous Organisms and Gas Microbubbles / $c Rachel E Kahn.
264 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2024
300 $a 1 electronic resource (110 pages)
336 $a text $b txt $2 rdacontent
337 $a computer $b c $2 rdamedia
338 $a online resource $b cr $2 rdacarrier
500 $a Source: Dissertations Abstracts International, Volume: 86-05, Section: A.
500 $a Advisors: Lavery, Andone C.
502 $b Ph.D. $c Massachusetts Institute of Technology $d 2024.
520 $a Broadband acoustical technology revolutionized our ability to explore, monitor, and operate in the ocean. While strides have been made in numerous physical and biological applications, there remain many standing scientific questions well suited to broadband approaches. Physics-based sound scattering models allow us to interpret and draw quantitative observations from measurements. Such models have been developed and used to assess the biomass of many types of marine organisms of ecological significance, but we lack rigorous scattering models for gelatinous organisms despite their possibly accounting for a significant proportion of global marine biomass. Additionally, acoustical techniques for characterizing microbubble populations have been established for decades, yet little is known about the spectral characteristics of dense microbubble clouds associated with estuarine tidal fronts. These bubbles facilitate air-sea gas exchange and could interfere with acoustical operations in coastal environments; however, the density and size distribution of the bubbles must be known to assess their impacts. This dissertation addresses these deficiencies in our application of broadband techniques. In Chapter 2, a sound scattering model for gelatinous organisms is developed based on the Distorted Wave Born Approximation. The 3-D model is applied to a species of scyphomedusa and verified with laboratory measurements of broadband backscattering from live individuals. The model predicts backscattering levels and broad spectral behavior within <2 dB. In Chapter 3, a towable instrument is developed for measuring broadband excess attenuation from bubbles from which the size distribution is inferred. The instrument is tested under breaking waves in a laboratory wave tank and then used to characterize the bubble size distribution in the Connecticut River tidal ebb plume front. In Chapter 4, broadband backscattering measurements from the Connecticut River front are used to infer the associated bubble size distribution. Spatial trends in the bubble size distribution are examined within the context of frontal kinematics. An observed disparity between the bubble size distribution measured with excess attenuation and volume backscattering is hypothesized to arise from a sampling bias caused by bubbles concentrated in the upper water column.
546 $a English
590 $a School code: 0753
650 4 $a Plankton. $3 1299572
650 4 $a Remote sensing. $3 535394
650 4 $a Bubbles. $3 1530439
650 4 $a Swimming. $3 638392
650 4 $a Oceanography. $3 535383
650 4 $a Endangered & extinct species. $3 3560222
650 4 $a Data processing. $3 680224
650 4 $a Biomass. $3 1013462
650 4 $a Rivers. $3 519737
650 4 $a Fluid mechanics. $3 528155
650 4 $a Extinction. $3 3685255
650 4 $a Fish. $3 3564374
650 4 $a Biological oceanography. $3 2122748
650 4 $a Microbiology. $3 536250
650 4 $a Recreation. $3 535376
690 $a 0204
690 $a 0799
690 $a 0416
690 $a 0410
690 $a 0814
710 2 $a Massachusetts Institute of Technology. $b Department of Mechanical Engineering. $e degree granting institution. $3 3817004
720 1 $a Lavery, Andone C. $e degree supervisor.
773 0 $t Dissertations Abstracts International $g 86-05A.
790 $a 0753
791 $a Ph.D.
792 $a 2024
856 4 0 $u https://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=31652265