Blar i Brage IMR på forfatter "Foote, Kenneth G."
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Comment on ''Some frequencies of underwater noise produced by fishing boats affecting albacore catch'' [J. Acoust. Soc. Am. 66, 296–299 (1979)]
Foote, Kenneth G. (Others, 1980)An alternative explanation for the observations analyzed by Erickson is offered. Differences in catch-related success of boats participating in the West Coast Albacore fishery are attributed to the low-frequency content ... -
Comments on "A generalized target strength model for euphausiids, with applications to other zooplankton" [J. Acoust. Soc. Am. 95, 2452–2466 (1994)]
Stanton, Timothy K.; Foote, Kenneth G. (Journal article; Peer reviewed, 1995)A major premise upon which this paper by Macaulay was written is flawed as is the formulation (both conceptually and mathematically) of the scattering models. The formulation is actually an assemblage and adaptation of ... -
Comparing high-frequency scattering by a fish swimbladder and a gas-filled ellipsoid
Foote, Kenneth G.; Francis, David T. I. (Others, 2004) -
Comparing Kirchhoff-approximation and boundary-element models for computing gadoid target strengths
Foote, Kenneth G.; Francis, David T. I. (Journal article; Peer reviewed, 2002)To establish the validity of the boundary-element method (BEM) for modeling scattering by swimbladder-bearing fish, the BEM is exercised in several ways. In a computation of backscattering by a 50-mm-diam spherical void ... -
Comparing repeated sidescan sonar measurements of benthic squid egg beds in Monterey Bay, CA
Foote, Kenneth G.; Iampietro, Pat J.; Young, Mary (Others, 2006) -
Comparison of copper and tungsten carbide calibration spheres
Foote, Kenneth G.; MacLennan, David N. (Journal article; Peer reviewed, 1984)The properties of calibration spheres made from electrical-grade copper, denoted Cu, and tungsten carbide with 6% cobalt binder, denoted WC, are examined theoretically. Effects of variations in material, medium, and equipment ... -
Comparison of equal-area cylindrical and circular piston transducers
Foote, Kenneth G. (ICES CM Documents;1994/L:29, Working paper, 1994)Design of sondes for in situ measurement of zooplankton or other scatterers requires choosing among alternative transducer geometries. This contribution addresses the problem of choosing between cylindrical and circular ... -
Comparison of two 120-kHz split-beam transducers
Foote, Kenneth G. (ICES CM Documents;1991/B:31, Working paper, 1991)The performance of two 120-kHz split-beam transducers is compared through the following measures: relative power level, directivity index, relative source level, and reverberation index or equivalent beam angle. Sidelobe ... -
Comparison of walleye pollock target strength estimates determined from in situ measurements and calculations based on swimbladder form
Foote, Kenneth G.; Traynor, Jimmie J. (Journal article; Peer reviewed, 1988)The target strength of walleye pollock (Theragra chalcogramma) at 38 kHz has been determined in each of two ways: (1) in situ measurement with dual-beam and split-beam echo sounders, and (2) theoretical calculation based ... -
Correcting acoustic measurements of scatterer density for extinction
Foote, Kenneth G. (Journal article; Peer reviewed, 1990)Extinction is sometimes a major problem in acoustic surveys of fish stocks, as it often occurs when the fish are concentrated and easiest to survey. The same may be true of certain macrozooplankton, such as krill in swarms. ... -
Cylindrical sonar design for fish echo surveying
Foote, Kenneth G. (ICES CM Documents;1988/B:3, Working paper, 1988)Most applications of echo integration involve use of a fixed single-beam transducer that is rather narrow and downwards-oriented. It is often desired to sense fish in other directions, for example, to assess components ... -
Definition of the problem of estimating fish abundance over an area from acoustic line-transect measurements of density
Foote, Kenneth G.; Stefánsson, Gunnar (ICES CM Documents;1990/D:25, Working paper, 1990)The problem of acoustic abundance estimation is briefly reviewed. Under proper conditions, fish density can be measured with high accuracy along line transects. Observed variations in fish density consequently reflect ... -
Dependence of equivalent beam angle on sound speed
Foote, Kenneth G. (ICES CM documents, Working paper, 1987)The equivalent beam angle is computed numericaily, according to its rigorous definition, for each of two transducers. These are those used with the SIMRAD split-beam echo sounders at 38 and 70 kHz. The results are expressed ... -
Depth-dependent target strengths of gadoids by the boundary-element method
Francis, David T. I.; Foote, Kenneth G. (Journal article; Peer reviewed, 2003)The depth dependence of fish target strength has mostly eluded experimental investigation because of the need to distinguish it from depth-dependent behavioral effects, which may change the orientation distribution. The ... -
Designing an improved transducer array geometry
Foote, Kenneth G. (ICES CM Documents;1988/B:2, Working paper, 1988)Improvements in a split-beam transducer that is also used for surveying are sought through changes in array geometry. These are assessed through relative changes in the sum of source level and voltage response and the ... -
Detecting Atlantic herring by parametric sonar
Godø, Olav Rune; Foote, Kenneth G.; Dybedal, Johnny; Tenningen, Eirik; Patel, Ruben (Journal article; Peer reviewed, 2010-03-17)The difference-frequency band of the Kongsberg TOPAS PS18 parametric sub-bottom profiling sonar, nominally 1–6 kHz, is being used to observe Atlantic herring. Representative TOPAS echograms of herring layers and schools ... -
Determining the extinction cross section of aggregating fish
Foote, Kenneth G.; Ona, Egil; Toresen, Reidar (Journal article; Peer reviewed, 1992)When fish are aggregated over a flat bottom, and fish and bottom echoes can be distinguished, it is possible to determine the fish extinction cross section by a simple application of the echo integration method. The theory ... -
Development of a fresh-water tank facility for calibrating multibeam sonar
Baldwin, Kenneth C.; Mayer, Larry A.; McLeod, Andrew; Foote, Kenneth G.; Chu, Dezhang; Beaudoin, Jonathan; Weber, Tom (Others, 2003) -
Digital representation of split-beam-transducer beam patterns
Foote, Kenneth G. (ICES CM Documents;1986/B:2, Working paper, 1986)The farfield beam pattern of each of two different split-beam transducers is computed and represented in the axial region by a finite number of constant levels. The accuracy of representation is determined as a function ... -
Directional properties of an 18-kHz transducer
Foote, Kenneth G. (ICES CM Documents;1993/B:29, Working paper, 1993)Several theoretical measures of directivity are given for an 18-kHz transducer that is used in both single-beam and split-beam applications, namely the SIMRAD transducer type 18-11 in the single-beam variant. These are ...