Blar i Brage IMR på emneord "VDP::Mathematics and natural science: 400::Physics: 430::Electromagnetism, acoustics, optics: 434"
Viser treff 1-20 av 26
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A unifying theory explaining different power budget formulations used in modern scientific echosounders for fish abundance estimation
(Fisken og Havet;7-2014, Research report, 2014-12-31)Acoustic methods used in fish abundance estimation constitute a key part of the analytic assessment that makes the basis for fisheries research and international regulations of marine resources. The methods rely on ... -
Aktiv forvaltning av marine verdier i kystsonen
(Research report, 2010-12) -
Akustikk og fiskeåtferd: korleis kan vi observera åtferd og kva finn vi ut?
(Conference object, 2010-09-15) -
Dependence of equivalent beam angle on sound speed
(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 ... -
Equivalent beam angles for several standard transducers
(ICES CM documents, Working paper, 1990)Nominal values for the equivalent beam angle are given for several transducers. These are the standard split-beam transducers designed for the SIMRAD EK500 scientific echo sounder, with operating frequencies of 38 and 120 ... -
Fitting observed fish trajectories to cathcability models
(Conference object, 2010-09-08) -
Lateral-aspect target strength measurements of in situ herring (Clupea harengus)
(Journal article; Peer reviewed, 2009-07)Surveys of schooling herring with the new multi-beam sonar (Simrad MS70) pose new challenges when converting the echo energy to estimates of biomass. Since the sonar projects horizontally, data and models of lateral-aspect ... -
Lateral-aspect target strength measurements of in situ herring (Clupea harengus)
(Journal article; Peer reviewed, 2009-07)Surveys of schooling herring with the new multi-beam sonar (Simrad MS70) pose new challenges when converting the echo energy to estimates of biomass. Since the sonar projects horizontally, data and models of lateral-aspect ... -
Mackerel behaviour and seismic signals - a pilot net pen study
(Rapport fra Havforskningen;19-2016, Working paper, 2016-04-28)English: A pilot study to investigate behavioural changes induced by sound exposure for mackerel was conducted in October 2015 at Austevoll research station. The main objective was to test the experimental set up, and ... -
Noise Dose for Aquatic Animals: Preliminary Estimates for Two Seismic Surveys
(Conference object, 2010-10)Two major air-gun exposure experiments have been conducted in Norwegian waters: The Nordkappbank experiment in 1992 [Can. J. Fish. Res. Aq. Sci., 1996, Vol. 53, pp. 2238-2249] and the Vesterålen experiment in 2009 [Fisken ... -
Noise dose for aquatic animals: Preliminary estimates for two seismic surveys. (A)
(Conference object, 2010-03)In humans, a daily noise dose is defined and used to regulate noise exposure in the working environment. This is an integrated measure of sound intensity over the working day, typically 8 h in duration. When investigating ... -
Observing school dynamics in situ using acoustics
(Conference object, 2010-04) -
Relasjoner mellom integrerte ekkointensiteter og fisketetthet
(Master thesis, 1975) -
Scheme for displaying fish position data in real time
(ICES CM documents, Working paper, 1987)Fish reaction to the passage of acoustic surveying vessels may be at least partly assessed through use of the angle data derived with the SIMRAD split-beam echo sounder. Several schemes are outlined for displaying and ... -
Sild skremmes ikke av fregattenes sonarer :: Herring are not frightened by frigate sonar
(Havforskningsnytt;Nr. 5 - 2012, Working paper, 2012)Den store bestanden av norsk vårgytende sild metter ikke bare millioner av mennesker, men er også mat for torsk, sel, spekkhogger og sjøfugl. Forsvarets nye fregatter er utstyrt med kraftige sonarer som potensielt kunne ... -
Simulations of multi-beam sonar echos from schooling individual fish in a quiet environment
(Journal article; Peer reviewed, 2012-12)A model is developed and demonstrated for simulating echosounder and sonar observations of fish schools with specified shapes and composed of individuals having specified target strengths and behaviors. The model emulates ... -
Sjå havet med nye øyre : Seing the sea with sound
(Havforskningsnytt;Nr. 10 - 2010, Working paper, 2010)Whales have developed an advanced biological sonar system that they can use to communicate between continents. They also use their sonar when hunting prey, and once a delicacy has been located, they can catch them in the ... -
SONATE - Sonar effects on marine life - aiding naval officers in planning safe operation of active sonar
(ICES CM documents, Conference object, 2006) -
SONATE - Sonar effects on marine life - aiding naval officers in planning safe operation of active sonar
(ICES CM documents, Conference object, 2006)