Doctoral theses
Current Record: 316 of 337
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Identifier |
uch.biology.phd//1994machias |
Title |
Το ηχοανακλαστικό δυναμικό της σαρδέλας (sardina pilchardus), και οι παράγοντες που το επηρεάζουν |
Alternative Title |
Factors affecting target strength of sardine (sardina pilchardus) |
Author
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Μαχιάς, Αθανάσιος Κ
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Thesis advisor
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Τσιμενίδης, Νικόλαος
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Abstract |
The present work examines the variations in the swimbladder volume, wsimbladder cross-sections and the target strenght(TS) of sardine(Sardina Pilchardus), in relation to the size and the intrinsic physiological factors of the fish(lipids, gonads, stomach).Totally 50 sardines were reconstructed in computer by digitizing. The volume of fish, swimbladder, gonads and stomach, as well as the maximum cross-section of swimbladder were calculated using the software "slicer". It was also calculated the lipid contents. It was found that the swimbladder volume and maximum cross-section can be estimated from two distinct modelsQone for the reproductive period and one for the reproductive dormant period. The theoretical expected T.S values of fish sampled with trawls-nets were compared with field measurements, taken with dual beam echo-sounder.Two different models were proposed for the simulation of the expected values. Comparison results were successful and confirmed tha estimated models can be used for the forecast of TS.
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Language |
Greek |
Subject |
ΑΛΙΕΥΤΙΚΑ ΥΔΡΟΑΚΟΥΣΤΙΚΑ; ΕΣΩΤΕΡΙΚΗΔΟΜΗ ΚΑΙ ΦΥΣΙΟΛΟΓΙΑ; ΗΧΟΑΝΑΚΛΑΣΤΙΚΟ ΔΥΝΑΜΙΚΟ; ΝΗΚΤΙΚΗ ΚΥΣΤΗ; Σαρδέλες |
Issue date |
1994-06-29 |
Collection
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School/Department--School of Sciences and Engineering--Department of Biology--Doctoral theses
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Type of Work--Doctoral theses
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Permanent Link |
https://elocus.lib.uoc.gr//dlib/a/f/0/metadata-dlib-1994machias.tkl
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Views |
240 |