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

Acoustic measurement techniques for ...

Mouraenko, Oleg A.

Linked to FindBook

Google Book

Amazon

博客來

Acoustic measurement techniques for suspended sediments and bedforms.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Acoustic measurement techniques for suspended sediments and bedforms./
Author:	Mouraenko, Oleg A.
Description:	169 p.
Notes:	Source: Dissertation Abstracts International, Volume: 65-12, Section: B, page: 6591.
Contained By:	Dissertation Abstracts International65-12B.
Subject:	Engineering, Marine and Ocean. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3158842
ISBN:	0496914073

Acoustic measurement techniques for suspended sediments and bedforms.
Mouraenko, Oleg A.

Acoustic measurement techniques for suspended sediments and bedforms. - 169 p.

Source: Dissertation Abstracts International, Volume: 65-12, Section: B, page: 6591.

Thesis (Ph.D.)--University of Florida, 2004.

The acoustic backscatter system provides a nonintrusive method for measuring of profiles of suspended sediment size and concentrations. Therefore, an inversion model is required to convert the recorded series of intensities into parameters of sediment suspension. The measurement precision highly depends on the choice of the inversion model. In this work the high-pass backscattering model is modified to allow accurate inversion for both sediment sizes and concentrations. The modified correction function with a single parameter is introduced for the form function and normalized cross-section. The parameters can be found from the calibration of the system in the chamber with generated homogeneous suspension. To account for the difference in shape and mineralogy, a set of two parameters can be determined for a particular sediment. Their use greatly improves the accuracy of mean sediment size measurements obtained with the three-frequency acoustic backscatter system.

ISBN: 0496914073Subjects--Topical Terms:

1019064
Engineering, Marine and Ocean.

Acoustic measurement techniques for suspended sediments and bedforms.
LDR:03218nmm 2200301 4500 001 1849827
005 20051203081256.5
008 130614s2004 eng d
020 $a 0496914073
035 $a (UnM)AAI3158842
035 $a AAI3158842
040 $a UnM $c UnM
100 1 $a Mouraenko, Oleg A. $3 1937761
245 1 0 $a Acoustic measurement techniques for suspended sediments and bedforms.
300 $a 169 p.
500 $a Source: Dissertation Abstracts International, Volume: 65-12, Section: B, page: 6591.
500 $a Chair: Andrew B. Kennedy.
502 $a Thesis (Ph.D.)--University of Florida, 2004.
520 $a The acoustic backscatter system provides a nonintrusive method for measuring of profiles of suspended sediment size and concentrations. Therefore, an inversion model is required to convert the recorded series of intensities into parameters of sediment suspension. The measurement precision highly depends on the choice of the inversion model. In this work the high-pass backscattering model is modified to allow accurate inversion for both sediment sizes and concentrations. The modified correction function with a single parameter is introduced for the form function and normalized cross-section. The parameters can be found from the calibration of the system in the chamber with generated homogeneous suspension. To account for the difference in shape and mineralogy, a set of two parameters can be determined for a particular sediment. Their use greatly improves the accuracy of mean sediment size measurements obtained with the three-frequency acoustic backscatter system.
520 $a The inversion model was applied to data obtained in the chamber with settling mixture of two sediment samples. The results were compared to the predictions by the 1D advection-diffusion model. Good agreement was shown for concentrations and sediment size measurements, with the error for sediment size approximation lying within the standard deviation of size distribution. The accuracy of the concentration measurements was different among the transducer frequencies, and was found to depend on the sensitivity of the transducer to the particular sediment size. The sediment sizes were estimated by minimizing the variance between concentrations, determined from different frequencies, and found to depend on the accuracy of estimated concentrations. For correction of recorded voltage data with applied time-varying gain, the system functions were found to be better approximated by second order polynomials.
520 $a A multiple reflection model was developed based on the multiple layer approximation. The numerical simulation with the initial uniform concentration profile of 3g/l shows that the effect in intensities from the multiple reflections can be up to 14%. Also, a bottom echo removal algorithm was developed in order to eliminate the effect of high intensity scattering on the concentration measurements close to the bottom.
590 $a School code: 0070.
650 4 $a Engineering, Marine and Ocean. $3 1019064
650 4 $a Physical Oceanography. $3 1019163
690 $a 0547
690 $a 0415
710 2 0 $a University of Florida. $3 718949
773 0 $t Dissertation Abstracts International $g 65-12B.
790 1 0 $a Kennedy, Andrew B., $e advisor
790 $a 0070
791 $a Ph.D.
792 $a 2004
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3158842