Acoustic characterization of Mysis relicta at multiple frequencies

Lars G. Rudstam; Frank R. Knudsen; Helge Balk; Gideon Gal; Brent T. Boscarino; Thomas Axenrot

doi:10.1139/f08-179

Acoustic characterization of Mysis relicta at multiple frequencies

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f08-179 ◽

2008 ◽

Vol 65 (12) ◽

pp. 2769-2779 ◽

Cited By ~ 15

Author(s):

Lars G. Rudstam ◽

Frank R. Knudsen ◽

Helge Balk ◽

Gideon Gal ◽

Brent T. Boscarino ◽

...

Keyword(s):

Average Length ◽

Target Strength ◽

Mysis Relicta ◽

Detection Range ◽

Acoustic Backscattering ◽

Acoustic Data ◽

Acoustic Characterization ◽

Lower Maximum ◽

Multiple Frequencies

We measured acoustic backscattering from Mysis relicta , a common invertebrate in northern lakes, using five frequencies (38, 120, 200, 430, and 710 kHz). Acoustic backscattering from mysids was highest at 430 kHz and lowest at 38 kHz (19 dB lower). Maximum difference between the four other frequencies was 5.2 dB. Mysid target strength (TS) ranged from –80.1 dB at 430 kHz to –99.4 dB at 38 kHz (12 mm average length, range 5–21 mm). A theoretical scattering model (Stanton’s fluid-like, bent-cylinder model) predicted TS within 0.3–1.9 dB of observed TS for the different frequencies. The detection range was lowest at 38 and 710 kHz and greatest at 120 and 200 kHz. Fish were common above the mysid layer and produced higher acoustic backscattering at 38 kHz than at the other frequencies. A combination of 38 kHz and 120 or 200 kHz provides a strong contrast between mysid and fish acoustic backscattering that would help separate these groups using acoustic data.

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Acoustic Characteristics of /s/ in Adolescents

Journal of Speech Language and Hearing Research ◽

10.1044/jslhr.4203.663 ◽

1999 ◽

Vol 42 (3) ◽

pp. 663-677 ◽

Cited By ~ 36

Author(s):

Peter Flipsen ◽

Lawrence Shriberg ◽

Gary Weismer ◽

Heather Karlsson ◽

Jane McSweeny

Keyword(s):

Reference Database ◽

Linguistic Context ◽

Spectral Moments ◽

Data Set ◽

Acoustic Characteristics ◽

Acoustic Data ◽

Acoustic Characterization ◽

Acoustic Analyses ◽

Age Range

The goal of the current study was to construct a reference database against which misarticulations of /s/ can be compared. Acoustic data for 26 typically speaking 9- to 15-year-olds were examined to resolve measurement issues in acoustic analyses, including alternative sampling points within the /s/ frication; the informativeness of linear versus Bark transformations of each of the 4 spectral moments of /s/ (Forrest, Weismer, Milenkovic, & Dougall, 1988); and measurement effects associated with linguistic context, age, and sex. Analysis of the reference data set indicates that acoustic characterization of /s/ is appropriately and optimally (a) obtained from the midpoint of /s/, (b) represented in linear scale, (c) reflected in summary statistics for the 1st and 3rd spectral moments, (d) referenced to individual linguistic-phonetic contexts, (e) collapsed across the age range studied, and (f) described individually by sex.

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Acoustic characterization of Mysis relicta

Limnology and Oceanography ◽

10.4319/lo.1999.44.2.0371 ◽

1999 ◽

Vol 44 (2) ◽

pp. 371-381 ◽

Cited By ~ 19

Author(s):

Gideon Gal ◽

Lars G. Rudstam ◽

Charles H. Greene

Keyword(s):

Mysis Relicta ◽

Acoustic Characterization

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Modelling the effect of swimbladder compression on the acoustic backscattering from herring at normal or near-normal dorsal incidences

ICES Journal of Marine Science ◽

10.1016/s1054-3139(03)00142-5 ◽

2003 ◽

Vol 60 (6) ◽

pp. 1381-1391 ◽

Cited By ~ 20

Author(s):

Natalia Gorska ◽

Egil Ona

Keyword(s):

Cross Section ◽

Acoustic Scattering ◽

Theoretical Work ◽

Target Strength ◽

Acoustic Backscattering ◽

Acoustic Data ◽

Backscattering Cross Section ◽

Entire Depth ◽

The Mean ◽

Theoretical Results

Abstract Inaccuracy in herring target strength can be an important source of bias in the acoustic assessment of several important herring stocks. New acoustic data on herring target strength (Ona et al., 2001, submitted for publication; Ona, 2003) confirm previous suggestions and evidence on a possible reduction of the size of the herring swimbladder as a result of its compression with increasing water depth. Theoretical work for a better understanding of the acoustic scattering from herring over its entire depth distribution may therefore be essential for improving abundance estimation. This study supplements the analysis, conducted by Gorska and Ona (2003) for herring averaged-backscattering cross-section. The modal-based, deformed-cylinder model (MB-DCM) solutions, presented in that paper, are used. The sensitivity of the herring backscattering cross-section in case of normal or near-normal dorsal incidences is studied with respect to frequency, contraction factors of the swimbladder dimensions and some fish morphological parameters. The study is important for a better understanding of not only the backscattering by individual fish for the dorsal incidence, but also the depth- and frequency-dependencies of the mean-backscattering cross-section. The theoretical results have been applied in the interpretation of the actual measured target-strength data on adult herring.

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In situ target-strength measurements of Chilean jack mackerel (Trachurus symmetricus murphyi) collected with a scientific echosounder installed on a fishing vessel

ICES Journal of Marine Science ◽

10.1093/icesjms/fsn043 ◽

2008 ◽

Vol 65 (4) ◽

pp. 594-604 ◽

Cited By ~ 15

Author(s):

Hector Peña

Keyword(s):

Target Strength ◽

Commercial Fishing ◽

Jack Mackerel ◽

Fishing Vessel ◽

Acoustic Backscattering ◽

Acoustic Data ◽

Fishing Vessels ◽

Single Target ◽

The Mean

Abstract Peña, H. 2008. In situ target-strength measurements of Chilean jack mackerel (Trachurus symmetricus murphyi) collected with a scientific echosounder installed on a fishing vessel. – ICES Journal of Marine Science 65: 594–604. The use of commercial fishing vessels for scientific purposes has increased worldwide in the past 10 years. Many such studies have involved the collection of acoustic data from both uncalibrated and calibrated echosounders. However, few studies have involved investigations of in situ target strength (TS). During August/September 2003, in situ TS data on Chilean jack mackerel (Trachurus symmetricus murphyi) were collected on board a commercial purse-seiner during normal fishing operations off Chile, using a 38 kHz, Simrad EK60 scientific echosounder. The single-target detections of Chilean jack mackerel were filtered by depth, off-axis beam angle, and beam-compensation criteria to improve the quality of the data used for the TS calculations. Two methods, using raw data and tracked data, were employed to calculate the mean acoustic-backscattering cross section (σbs) and mean TS of Chilean jack mackerel. The results of the two approaches gave similar results, with a strong mode in the mean TS distribution between −35 and −37 dB for fish lengths ranging from 26 to 34 cm, indicating a b20 value of −66 dB. These results agreed well with most results published for this species and others of the same genus (i.e. T. trachurus, Trachurus t. capensis, and T. japonicus).

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Acoustic Characterization of Marine Sediments

10.21236/ada627576 ◽

1997 ◽

Author(s):

Anatoliy N. Ivakin ◽

Darrell R. Jackson

Keyword(s):

Marine Sediments ◽

Acoustic Characterization

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Low temperature acoustic characterization of PMN single crystal

Journal of Applied Physics ◽

10.1063/1.5000361 ◽

2017 ◽

Vol 122 (8) ◽

pp. 084103 ◽

Cited By ~ 1

Author(s):

E. Smirnova ◽

A. Sotnikov ◽

S. Ktitorov ◽

H. Schmidt

Keyword(s):

Low Temperature ◽

Single Crystal ◽

Acoustic Characterization

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Acoustic characterization of silica nanoparticle-impregnated Kevlar fabric

Textile Research Journal ◽

10.1177/00405175211023812 ◽

2021 ◽

pp. 004051752110238

Author(s):

Oluwafemi P Akinmolayan ◽

James M Manimala

Keyword(s):

Transmission Loss ◽

Silica Nanoparticle ◽

Air Gap ◽

Thin Plates ◽

Residual Porosity ◽

Ballistic Performance ◽

Number Of Layers ◽

Structural Applications ◽

Acoustic Characterization

Silica nanoparticle-impregnated Kevlar (SNK) fabric has better specific ballistic performance in comparison to its neat counterparts. For multifunctional structural applications using lightweight composites, combining this improved ballistic functionality with an acoustic functionality is desirable. In this study, acoustic characterization of neat and SNK samples is conducted using the normal-incidence impedance tube method. Both the absorption coefficient and transmission loss (TL) are measured in the 60–6000 Hz frequency range. The influence of parameters such as number of layers of neat or treated fabric, percentage by weight of nanoparticle addition, spacing between fabric layers, and residual porosity is examined. It is found that while absorption decreases with an increase in nanoparticle addition for frequencies above about 2500 Hz, increasing the number of layers shifts peak absorption to lower frequencies. By introducing an air-gap behind the fabric layer, dominant low-frequency (1000–3000 Hz) absorption peaks are obtained that correlate well with natural modes of mass-equivalent thin plates. Examining the influence of residual porosity by laminating the SNK samples reveals that it contributes to about 30–50% of the total absorption. Above about 1500 Hz, 3–5 dB of TL increase is obtained for SNK samples vis-à-vis the neat samples. TL is found to increase beyond that of the neat sample above a threshold frequency when an air-gap is introduced between two SNK layers. With an increase in the weight of nanoparticle addition, measured TL tends to be closer to mass law predictions. This study demonstrates that SNK fabric could provide improved acoustic performance in addition to its ballistic capabilities, making it suitable for multifunctional applications and could form the basis for the development of simplified models to predict the structural acoustic response of such nanoparticle–fabric composites.

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Acoustic Characterization of Some Steel Industry Waste Materials

Applied Sciences ◽

10.3390/app11135924 ◽

2021 ◽

Vol 11 (13) ◽

pp. 5924

Author(s):

Elisa Levi ◽

Simona Sgarbi ◽

Edoardo Alessio Piana

Keyword(s):

Thermal Characteristic ◽

Environmental Benefits ◽

Acoustic Properties ◽

Physical Parameters ◽

Industry Waste ◽

Acoustic Characterization ◽

Minimization Procedure ◽

The Difference ◽

By Products

From a circular economy perspective, the acoustic characterization of steelwork by-products is a topic worth investigating, especially because little or no literature can be found on this subject. The possibility to reuse and add value to a large amount of this kind of waste material can lead to significant economic and environmental benefits. Once properly analyzed and optimized, these by-products can become a valuable alternative to conventional materials for noise control applications. The main acoustic properties of these materials can be investigated by means of a four-microphone impedance tube. Through an inverse technique, it is then possible to derive some non-acoustic properties of interest, useful to physically characterize the structure of the materials. The inverse method adopted in this paper is founded on the Johnson–Champoux–Allard model and uses a standard minimization procedure based on the difference between the sound absorption coefficients obtained experimentally and predicted by the Johnson–Champoux–Allard model. The results obtained are consistent with other literature data for similar materials. The knowledge of the physical parameters retrieved applying this technique (porosity, airflow resistivity, tortuosity, viscous and thermal characteristic length) is fundamental for the acoustic optimization of the porous materials in the case of future applications.

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