Blar i Articles på emneord "echo sounder"
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Bat sonar and the role of frequency diversity
(Others, 2006) -
Broadband echo spectra from euphausiids and copepods
(Others, 2000) -
Coincidence echo statistics
(Journal article; Peer reviewed, 1996)Two scatterers at similar range give an echo which may appear to be due to a single scatterer. Methods for determining target strength that depend on resolving single scatterers may fail in this instance. Statistics ... -
Comparison of copper and tungsten carbide calibration spheres
(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 ... -
Estimating tail-beat frequency using split-beam echosounders
(Journal article; Peer reviewed, 2009-02-04)Data from a standard split-beam echosounder are used to estimate tail-beat frequency within a dense herring (Clupea harengus L.) layer. The data were collected by lowering a horizontally projecting 38 kHz split-beam ... -
Fish target strengths for use in echo integrator surveys
(Journal article; Peer reviewed, 1987)In situ measurements of fish target strength are selected for use in echo integrator surveys at 38 kHz. The results are expressed through equations in which the mean target strength TS is regressed on the mean fish length ... -
Herring tilt angles, measured through target tracking
(Report / Alaska Sea Grant College Program, Chapter, 2001)The target strength of herring in captivity was monitored experimentally at three frequencies (18, 38, and 120 kHz) over a period of 3 years using split-beam echo sounders. One of the fundamental parameters of a target ... -
Influence of Different Factors on Abundance Estimates Obtained from Simultaneous Sonar and Echo Sounder Recordings
(Journal article; Peer reviewed, 2011-12-28)Use of horizontal guided sonar in addition to vertical echo sounder may improve biomass estimation of pelagic fish schooling near the surface. But proportions of horizontal guided sonar to vertical echo integration estimates ... -
Measurement of fish target strength with a split-beam echo sounder
(Journal article; Peer reviewed, 1986)Data derived with a 38-kHz split-beam echo sounder have been analyzed to yield target strengths suitable for use with echo integrators. This has required compensation for both thresholding and saturation, since these ... -
Optimizing copper spheres for precision calibration of hydroacoustic equipment
(Journal article; Peer reviewed, 1982)n operational definition of backscattering cross section is developed for the wideband reception of finite echoes. This is supported by relative measurements on a set of copper spheres by each of four echo sounders operating ... -
Postprocessing system for echo sounder data
(Journal article; Peer reviewed, 1991)Echo sounding is a powerful and widely used technique for remote sensing of the marine environment. In order to enhance the power of the echo sounder, a postprocessing system has been designed and realized in standard ... -
Probing the deep: Acoustic characterization of the Mid-Atlantic Ridge ecosystem
(Journal article; Peer reviewed, 2006) -
Spheres for calibrating high-frequency broadband echo sounders
(Others, 1999) -
Tracking individual fish from a moving platform using a split-beam transducer
(Journal article; Peer reviewed, 2005)Tracking of individual fish targets using a split-beam echosounder is a common method for investigating fish behavior. When mounted on a floating platform like a ship or a buoy, the transducer movement often complicates ...