Blar i Havforskningsinstituttet på emneord "akustikk"
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1992 ICES coordinated acoustic survey of ICES divisions IVa, IVb and VIa
(ICES CM Documents;1993/H:11, Working paper, 1993)This papers provides a report on the combined acoustic survey of herring stocks in the North Sea and ICES Division IVa in July 1992. Surveys by Norway, Scotland and the Netherlands are included covering the period 24 ... -
1993 ICES coordinated acoustic survey of ICES Division IVa, IVb and VIa
(ICES CM Documents;1994/H:22, Working paper, 1994)Summary: This paper provides a report on the combined acoustic survey of herring stocks in the North Sea and ICES division IVaN in June-July 1993. The surveys were carried out by Norway, Scotland, Denmark and Netherlands ... -
1994 ICES coordinated acoustic survey of ICES Divisions IVa, IVb, VIa and VIIb
(ICES CM Documents;1995/H:15, Working paper, 1995)Summary: Six surveys were carried out during late June and July covering most of the continental shelf North of 54°N in the North Sea and Ireland to the west of Scotland to a northern limit of 62°N. The eastern edge of ... -
1995 ICES coordinated acoustic survey of ICES Divisions IVa, IVb, VIa and VIIb
(ICES CM Documents;1996/H:8, Working paper, 1996)Summary: Seven surveys were carried out during late June and July covering most of the continental shelf North of 54°N in the North Sea and Ireland to the west of Scotland to a northern limit of 62°N. The eastern edge ... -
1996 ICES coordinated acoustic survey of ICES Divisions IIIa, IVa, IVb and VIa
(ICES CM Documents;1997/H:11, Working paper, 1997)Summary: Seven surveys were carried out during late June and July covering most of the continental shelf north of 54°N in the North Sea and lreland to the west of Scotland to a northern limit of 62°N. The eastern edge of ... -
1997 ICES coordinated acoustic survey of ICES Division IIIa, IVa, IVb and VIa
(ICES CM Documents;1998/OPEN:22, Working paper, 1998)Summary: Six surveys were carried out during late June and july covering most of the continental shelf north of 54°N in the North Sea and lreland to the west of Scotland to a northern limit of 62°N. The eastern edge of ... -
1999 ICES coordinated acoustic survey of ICES Divisions IIIa, IVa, IVb and VIa
(ICES CM Documents;2000/K:39, Working paper, 2000)Five surveys were carried out during late June and July covering most of the continental shelf north of 54°N in the North Sea and Ireland to the west of Scotland to a northern limit of 62°N. The eastern edge of the survey ... -
2000 ICES coordinated acoustic survey of ICES Division IIIa, IVa, IVb and VIa (North)
(ICES CM Documents;2001/P:28, Working paper, 2001)Six surveys were carried out during late June and July covering most of the continental shelf north of 54°N in the North Sea and to the west of Scotland to a northern limit of 62°N. The eastern edge of the survey area ... -
A field intercomparison between an acoustic current profiler / ADCP and two Savonius type current meters
(ICES CM Documents;1990/C:30, Working paper, 1990)During an introductory experiment in Lofoten May 1990 data from a vessel mounted ADCP on an anchored research vessel were intercompared with corresponding data from two anchored rotor current meters in a region where the ... -
A PC-based echo integrator system appliable for school structure analyzis
(ICES CM Documents;1991/B:43, Working paper, 1991)A low cost system for integration of echo signals on a PC has been developed. The system calculates the area backscattering strength in surface and bottom layers, and is designed both for the purpose of conventional ... -
A stationary acoustic system for monitoring undisturbed and vessel affected fish behaviour
(ICES CM Documents;1996/B:12, Working paper, 1996)Thorough knowledge of the dynamics of natural fish behaviour and distribution within a survey and among surveys is fundamental for reliability of time series of abundance indices. Further, vessel/trawl affected avoidance ... -
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 ... -
A unifying theory explaining different power budget formulations used in modern scientific echosounders for fish abundance estimation
(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 power ... -
Absorption of acoustic energy in dense herring schools studied by the attenuation in the bottom echo signal
(ICES CM Documents;1990/B:2, Working paper, 1990)The absorption of acoustic energy in herring schools is studied by echo integration of the bottom signal under various densities of herring. The investigations were carried out in a fjord in northern Norway, where large ... -
Abundance estimation of pelagic fish stocks by acoustic surveying
(ICES CM Documents;1991/B:33, Working paper, 1991)The echo integration technique is outlined. Weaknesses are identified and remedies described. While the technique is adequate for surveying some stocks, improvements are necessary for its proper application to others. ... -
Acoustic abundance estimate of 0-group north-east Arctic cod and haddock
(ICES CM Documents;1997/BB:15, Working paper, 1997)The abundance of the 1991-1994-year classes of north-east Arctic cod and haddock at the age of six month have been estimated on the basis of Norwegian acoustic data from the International 0-group fish survey in the Barents ... -
Acoustic abundance estimation of midwater animals
(Journal article; Peer reviewed, 1999) -
Acoustic abundance estimation of the Icelandic stock of capelin : 1978-1982
(Working paper, 1982)During the period October 1978 - february 1982 several abundance estimates and yearclass composition of the Icelandic capelin stock were obtained by acoustic methods. Surveying has been carried out in July-Agust, September, ... -
Acoustic abundance estimation of the stock of Norwegian spring spawning herring, winter 1995- 1996
(ICES CM Documents;1996/H:33, Working paper, 1996)Standard echo integration methodology has been applied to the stock of Norwegian spring spawning herring (Clupea harengus) wintering in the Ofotfjord-Tysfjord-Vestfjord system during late autumn 1995 and early winter ... -
Acoustic abundance estimation of wintering Norwegian spring spawning herring, with emphasis on methodological aspects
(ICES CM Documents;1994/(B+D+G+H):1, Working paper, 1994)The spawning component and part of the juvenile stock of Norwegian spring spawning herring have been wintering in a fjord system in northern Norway in recent years. Conditions for measuring the stock size have been ...