• Title/Summary/Keyword: 어획성능

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저예망 어구의 발줄 및 저질의 종류에 따른 역학적 특성

  • 신정욱;이주희;권병국
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2001.10a
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    • pp.79-80
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    • 2001
  • 저층트롤 어업은 주로 고가의 저서성 어족을 대상으로 조업이 이루어지고, 어구의 구조나 규모가 다양하며 발줄은 어구의 접지성을 유지하는 기능과 함께 어군을 망구에 구집 하는 역활을 한다. 저층 예망어구는 해저를 소해 하면서 예방하기 때문에 해저와의 마찰 저항이 많을 뿐만 아니라 뻘을 뜨거나 장애물에 걸리는 사고가 발생하기도 하여, 어획성능에도 많은 영향을 받는다. 이에 대한 연구로써, 독일에서는 빔 트롤의 체인의 형태에 따른 모형 트롤어구의 역학적 특성을 실험(1997, Uwe Richter)한 바가 있고, 일본에서도 발줄의 형상에 관한 연구(1992,Fuwa)가 있다. (중략)

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Elasticity of the Funnel Ribs and Hydrodynamic Characteristics on the Sea Eel Pots (장어통발의 깔대기 탄성과 유체역학적 특성)

  • Kim, Yong-Hae;Ha, Jeong-Sik
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.23 no.4
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    • pp.157-162
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    • 1987
  • The basic experiments on the plastic sea eel pots used in fishing were carried out in order to investigate the elasticity of the funnel ribs, hydrodynamic resistance, sinking time and diffusion of the bait from June to October, 1987. The elasticity of the bamboo funnel ribs was higher than that of the polypropylene ribs up to the load 150g. The hydrodynamic resistance R (kg) of the pots towing to the head direction horizontally in relation to towing velocity V (m/sec) was expressed as following formula; R=0.36V super(2.01) and coefficient of drag C sub(D) was 0.52. The sinking times of the covered pots by tape fully or partially were late 1-2 second than the typical pots within the water depth 7.5m. The diffusion tendency through the covered pots using dye and sardine extracts solution was concentrated to the entrance more than the typical pots. However, fishing efficiency as number and weight of fish per pots for nine times fishing operation was revealed no difference between the covered pots and the typical pots.

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Improvement of the Fishing Gear and Fishing Method of the East-Sea Trawl Fishery (동해구 트롤 어구어법의 개량)

  • 권병국;이주희;이춘우;김형석;김용식;안영일;김정문
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.37 no.2
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    • pp.106-116
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    • 2001
  • A serious of studies on the fishing gear and system of the East Sea trawl fishery was carried out to improve the fishing efficiency and the working conditions. As the first step of these studies, the fishing gear and system of the traditional East Sea trawl were checked in order to solve the some problems, such as the poor sheering efficiency of net mouth, the inconvenient fishing system of the side trawl and etc. And then the fishing system was reorganized from the side trawl into the stern trawl by setting up the net drum system on the stern deck, and introduction of two types of new designed nets, one for mainly the midwater trawl and the other for the bottom trawl. The results of the field experiment on the modified system and nets can be summarized as follows : 1. the modified system was well worked and could save the man-labour by about 80%. 2. The sheering efficiency of the improved net, A type was improved to 20 m height and 30 m width in the net mouth, and that of B type net, to 10 m height and 33 m width, compared with 1.5 m height and 15 m width in the traditional net. 3. Catch efficiency of pink shrimp in A or B type net was better about 3 or 5 times than that of traditional net, and in B net, for herring and other bottom fishes is better about 2 times than that of the traditional net.

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Color Preference of Webfoot Octopus and Improvement of Fishing Pots (주꾸미의 색에 대한 선택성과 단지의 개량)

  • Im, Seong-Ho;Go, Gwan-Seo;Gwon, Byeong-Guk
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.26 no.3
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    • pp.237-243
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    • 1990
  • For the improvement of the traditional pots which is using purple spirals for fishing webfoot octopus, Octopus Ocellatus GRAY, some experiments are carried out on the color preference in water tank and also operated practical experiment with PVC pots at sea for the comparison on the basis of the above water tank experiment. The results obtained are as follows: 1. The colors which webfoot octopus prefer in water tank or at sea are gray, red and green in order. 2. The catching efficiency of the pots with small spout(dia. 40mm) is better than that of large spout(dia. 50mm). 3. The results of fishing efficiency between PVC pots and purple spirals are shown almost same tendency.

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Mechanization of Fishing Operation on the Sea Eel Pots (장어통발 어업의 자동기계화에 관한 연구)

  • Ha, Jeong-Sik;Kim, Yong-Hae;Jang, Chung-Sik
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.26 no.1
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    • pp.45-50
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    • 1990
  • The basic investigation of the sea eel pots fisheries by questionnarie observation and dimension of the pots by fishing operation were carried out in order to develop for mechanical hauling system with 20~50 gross tonnage fishing boats from June to December, 1988. Number and weight of fish per pot between smaller diameter 11cm and larger 13cm of the pot have no significance so that the drag of the smaller pots can be decreased about 20% than the larger pots. The operating time by two men from opening to closing with screwing lock entrance was slightly faster than that by three men with knotting entrance even though the losses with two kinds of entrances while fishing operation were about the same. It was very reasonable that stone and lead sinker on the main line were substitute for two or three lead core P.P rope to make it smooth surface of the main line for mechanization of the continuous fishing operation.

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A study on the survival rate of escaped fish from trawl codend -Comparison of survival rate for fish species- (끌그물에서 탈출한 어류의 생존율에 관한 연구 - 어종별 생존율 비교 -)

  • 양용수;안희춘;박창두;조삼공;정의철;백철인
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2001.05a
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    • pp.81-82
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    • 2001
  • 최근 세계는 각종 어로기기 및 어구어법 기술의 발달로 인한 자원남획에 대한 우려로 자원관리형 어업에 대해 새로운 인식을 하게 되었고, 남획문제를 해결하기 위한 다각도의 노력을 기울이고 있다. 그러나 우리 나라 연근해에서 조업하고 있는 대표적인 어업인 트롤어업은 타 어구에 비하여 어획성능이 매우 우수하여 자원남획의 소지가 많고, 다이아몬드형 망지의 구조적 특성으로 인해 소형어류의 탈출이 어렵고, 탈출한 어류도 탈출시의 어체손상으로 생존율이 극히 저조할 것으로 추정되어 자원관리의 주 대상 어업으로 등장하고 있는 실정이다. (중략)

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감천항 방파제 부근수역에서 충돌위험

  • 최지웅
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2023.05a
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    • pp.245-245
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    • 2023
  • 감천항 내에는 벌크선석, 어획물 전용 냉동창고, 어획물 공동경매장 및 수리조선소등이 있다. 다양한 목적의 선석과 시설에 따라 조종불능선, 조종성능제한선, 견시불량선, 대형벌크선, 강제도선면제선박 및 어선등 이 감천항 방파제 부근수역을 이용한다. 특히 입출항하는 GT 20,000톤 - 50,000톤 크기의 벌크선박과 VHF교신이 되지 않는 어선들과 방파제 부근수역에서 조우상태가 되어 충돌사고 발생 위험이 존재한다. 따라서, 본연구는 선박 충돌사고를 예방하기 위하여 충돌위험요소를 확인하고 충돌위험요소 제거를 위한 방안을 모색하였으며, 또한 더욱 세심한 연구가 진행되기 위함을 목적으로 한다.

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Fishing Mechanism of Pots and their Modification 5. An Experiment for Modifying the Pot for Conger Eel, Astroconger myriaster (통발어구의 어획기구 및 개량에 관한 연구 5. 붕장어통발의 개량실험)

  • KIM Dae-An;KO Kwan-Soh
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.23 no.4
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    • pp.315-322
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    • 1990
  • In order to find out the most favorable shape and structure of pot for conger eel, Astroconger myriaster(Brevoort), the box type, tube type and flat box type of net pots and the pipe type of plastic pot were prepared. Then, the ability of the pots attracting the eel into them were investigated through a tank experiment. The attracting ability was highest in the pipe type without distinction of its length, 50cm and 60cm. In the flat box type, the effective height of pot and the diameter of entrance tip turned out 5cm respectively. But the ability was very poor in the rest pots, especially in the tube type. Thus, the pipe type and flat box type of pots were employed again in a field experiment for comparing their catches with those of the conventional bamboo and plastic pots. In the experiment, the catches were the most in the pipe type and second in the flat box type. But the bamboo and plastic pots both produced comparatively low catches, showing no significant difference between them. It was therefore concluded that the pipe type of pot might be the most favorable one for catching the conger eel.

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