Blar i Articles på utgivelsesdato
Viser treff 41-60 av 3001
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Havforskningsinstituttet tener fiskarane sine interesser betre i dag enn for 15-20 år sidan
(Journal article, 1980-08) -
Ressursane i åra som kjem
(Journal article, 1981) -
Torskefiskeria i 1980-åra
(Journal article, 1981) -
Variasjonar i utbredelsen av torsk i Barentshavet i perioden 1977-1981
(Journal article, 1981) -
Ressursprognoser for norsk fiske i 80-årene
(Journal article, 1981) -
The influence of wind-induced bubbles on echo integration surveys
(Journal article, 1981)An investigation of attenuation of acoustic energy caused by gas bubbles in the surface layers has been carried out. This was done primarily to study the effect on echo integration of fish abundance when using hull-mounted ... -
Gytebestandane bør haldast rimeleg store for å sikra større og jamnare produksjon
(Journal article, 1981-08) -
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 ... -
Bestandssituasjonen for torsken i Barentshavet og fisket i åra framover
(Journal article, 1982-03) -
Maintaining precision calibrations with optimal copper spheres
(Journal article; Peer reviewed, 1983)Effects of variations in quantities influencing the backscattering cross sections of solid elastic spheres are studied through a particular case. This is that of the 60-mm-diam copper sphere, which is being used worldwide ... -
Linearity of fisheries acoustics, with addition theorems
(Journal article; Peer reviewed, 1983)An experiment to verify the basic linearity of fisheries acoustics is described. Herring (Clupea harengus L.) was the subject fish. Acoustic measurements consisted of the echo energy from aggregations of encaged but otherwise ... -
Validation of age estimation in the Harp seal, Phoca groenlandica, using dentinal annuli
(Journal article; Peer reviewed, 1983)We investigated the validity and accuracy of age estimation in harp seals, Phoca groenlandica, using a sample of 155 known-age teeth from seals age 3 mo to 10 yr. Under transmitted light, transverse sections of harp seal ... -
Lodda i Barentshavet, bestand og beskatning
(Chapter, 1983) -
Investigation into the fate of C-14-labelled xenobiotics(naphthalene, phenanthrene, 2,4,5,2 ',4',5 '-hexachlorobiphenyl, octachlorostyrene) in Bermudian corals
(Journal article; Peer reviewed, 1983-02-28)Uptake and elimination of 4 labelled lipid-soluble xenobiotics (naphthalene, phenanthrene, 2,4,5,2',4',5'-hexachlorobiphen(yPlC B), octachlorostyrene) were studied in 19 anthozoans and 1 hydrozoan common to Bermudian ... -
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 ... -
Uptake and elimination of aromatic hydrocarbons a chlorinated biphenyl in eggs and larvae of cod Gadus morhua
(Journal article; Peer reviewed, 1984)Artificially fertilized eggs and newly hatched larvae of cod Gadus rnorhua L. were exposed to 14C labelled naphthalene, phenanthrene, benzo(a)pyrene and 2. 4. 5. 2', 4', 5'-hexachlorobiphenyl (PCB) for 24 h and thereafter ... -
Rather-high-frequency sound scattering by swimbladdered fish
(Journal article; Peer reviewed, 1985)A new model describes acoustic scattering by swimbladdered fish of lengths from at least 8 to 36 wavelengths. It represents a fish by an ideal pressure-release surface having the exact size and shape as the swimbladder. ... -
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 ... -
Acoustic estimation of size distribution and abundance of zooplankton
(Journal article; Peer reviewed, 1986)A series of investigations were undertaken to observe and describe the sound backscattering process from larger zooplankton (euphausiids). The target strength versus frequency, size, and aspect angle of the organism was ...