• 제목/요약/키워드: Small Fishing

검색결과 476건 처리시간 0.028초

강릉시 연안 문어어업에 관한 연구- I - 통발어업 - (Octopus fisheries in the coastal waters of Gangneung - I - Pot fishery -)

  • 안영일;박진영
    • 수산해양기술연구
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    • 제41권4호
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    • pp.271-278
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    • 2005
  • In order to study the catch situation of the octopus pot fishery in the coastal waters of Gangneung, catch quantities and weight per month and depth, the soaking time & loss of fishing gear were studied based on 62 fishing times (1 set consisted of 150 pots which is equivalent to 1 fishing time) over a period of 10 months from February to December 2003 using commercial fishing vessels and training ships. The monthly CPUE was generally high in the months of june - September, and during this period July showed the highest quantity (134g/pot, 19.21kg/haul). In consideration of the fact that octopus below the weight of 2kg is protected in foreign countries, the majority of the catch was small with 76% (486 octopuses) below 1kg. The octopus catch quantity was high in depth of more than 40m, and the average catch number per set of pots in depths of over 50m was the highest with 13 octopuses. CPUE(g/pot) was the highest at a depth of over 60m recording 101. In terms of catch quantity per soaking time (4-18 days) the highest was on the 7th day, and 13-18 days also recorded high catches, and this suggests the possibility of ghost - fishing with the loss of fishing gear. Loss of fishing gear was the highest in terms of loss frequency and amount at depths of 20-30m. Consequently, it seems that octopus pot fishing at depths of more than 30m would relieve friction with other types of fishing and increase fishing efficiency.

여수연안 정치망어장의 환경요인과 어황변동에 관한 연구 - 4 . 수온 염분과 어획량 변동 - (Environmental Factors and Catch Fluctuation of Set Net Grounds in the Coastal Waters of Yosu - 4 . Water Temperature and Salinity and Fluctuation of Catch -)

  • 김동수;노홍길
    • 수산해양기술연구
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    • 제32권2호
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    • pp.125-131
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    • 1996
  • In order to investigate the relation between the environmental properties and the catch fluctuation of set net fishing grounds located in the coastal waters of Yosu, oceanographic observations on the fishing grounds were carried out by the training ship ofYosu Fisheries University from January, 1990 to September, 1992, and the data obtained were compared with the catch data from the joint market ofYosu fisheries cooperative society from 1984 to 1993. The resuItes obtained are summerized as follows : 1. The ranges of water temperature and salinity in the fishing ground was 7.0 to $27^{\circ}C.$and 26.6 to 33.2${\textperthousand}$, and water temperature increased from March to August and decreased from September to February of following year. 2. The salinity in the fishing grounds was relatively high without significant changes from November to June of the following year. From July, however, the salinity decreased to continue a low value till September and then increased. The salinity in the fishing ground was dominated mainly by the precipitation and its variation was large at the north entrance of set net fishing ground, influenced greatly by the land waters from the river of Somjin, but small in the offshore of the fishing grounds. 3. The fishes caught by the set nets were arranged in order of catch as follows; Spanish mackerel> Horse mackerel > Sardine > Anchovy > Hair tail. The catches of Anchovy and Sardine were high in April to May and those of Hair tail in June to July, but Spanish mackerel and Horse mackerel were caught for whole period of fishing. Spanish mackerel was caught most in September and least in April and their means were largest in August and smallest in June. 4. The ranges of optimum water temperature for fishing by the set nets was 13.5 to $25^{\circ}C.$, and in the ranges the catches increased with increasing temperature. The ranges of optimum salinity for fishing varied between 25.0 and 32.0${\textperthousand}$.

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CFD 시뮬레이션 기반 소형 어선의 표준재화상태에 따른 조종성능 평가 (Evaluation of Maneuverability of Small Fishing Vessels Based on CFD Simulation under Standard Loading Condition)

  • 이선우;김상현;김혜우;윤형석;송창우;오주형
    • 해양환경안전학회지
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    • 제30권4호
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    • pp.348-357
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    • 2024
  • 상선에 비해 잦은 변침을 하고 어획물로 인한 중량 및 무게중심의 변화와 같은 다양한 운항조건을 가진 어선의 경우, 조종성능은 선박 운항 시에 매우 중요한 역할을 한다. 소형 어선의 사고는 2022년 기준 전체 해상 사고의 약 60%를 차지하며, 이는 부족한 조종성능으로 인한 충돌과 좌초 사고가 주요 원인이다. 특히 10톤 미만의 소형선박에서 발생한 사고는 전체 사고의 약 65%를 차지하는데, 소형 어선의 조종성능 관련 기준이 부재하여 이를 정확히 평가하기엔 어려움이 있다. 이에 본 연구에서는 4.99톤급 소형 어선을 대상선으로 선정하여 3D-CAD로 모델링 한 후, 상용 수치해석 프로그램인 STAR-CCM+를 활용하여 선박의 조종운동 시뮬레이션 환경을 구축하였다. 이를 바탕으로 다양한 표준재화상태와 무게중심을 고려하여 10° / 10° 및 20° / 20° zigzag test와 35° turning test를 수행하였고, 선체 중량이 증가함에 따라 변침성능이 감소하고 선회성능이 향상되는 경향을 분석하였다. 그 중, 만재출항과 부분만재입항 상태에서는 상대적으로 선회성능이 부족한 결과를 확인하였다. 이를 바탕으로 소형선박의 안전한 운항을 위한 표준재화상태와 무게중심을 고려한 조종성능의 평가 및 그에 상응하는 표준화된 조종성능 평가 기준의 필요성을 제시하였다. 또한, 본 연구의 조종성능 평가 결과가 소형선박의 조종성능 평가 기준 선정을 위한 기초자료로 활용될 수 있을 것으로 기대된다.

소형 어선용 이중강판 방향타의 유체역학적 특성 조사 (Investigation on the Hydrodynamic Characteristics of Double Plate Steel Rudder for Small Fishing Boat)

  • 안남현;박희승
    • 동력기계공학회지
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    • 제16권6호
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    • pp.24-29
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    • 2012
  • In this study, the numerical simulation has been performed to investigate the hydrodynamic evaluation between double plate steel rudder and newly designed foil type rudder for small fishing boat. The simulations are carried out in 2 speed ranges with 7 variations of flow's angle of attack which is at intervals of about 5 degree respectively. As the well-known commercial code, FLUENT and CATIA are used as the solver. The simulation results show that new designed foil type rudder is better than conventional double plate rudder in terms of Lift and Drag of running boat in the water.

외판 전개를 응용한 무형틀 FRP선박 건조방법 (Production Method of FRP Boat Using Developable Surface without a Mould)

  • 양지만;하윤석;김효철
    • 대한조선학회논문집
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    • 제42권5호
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    • pp.506-515
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    • 2005
  • Novel ships are commonly required iterative hull form modifications until she get reputation for new marine environment. Small FRP boats are manufactured in a identical shape with a mould. It implies that every modification step requires great time and expense which makes it difficult to improve the hull form promptly. Domestic hull form of small fishing boat of force has been evolved from the traditional hull form of developable shape. Utilizing this typical developable characteristics of small boats, ,New mouldless production method for FRP boat has been suggested and it is confirmed that the method is recommendable for a petty order of hull in evolving period of hull form development.

레이더 신호의 실시간 추출을 위한 소형 레이더 목표 추출기 개발 (Manufacture of a Small RTE for Real-Time Extraction of Radar Signal)

  • 성태경;김동식;조형래
    • 한국전자파학회논문지
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    • 제15권9호
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    • pp.835-840
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    • 2004
  • 현재 사용되고 있는 소형 레이더 장치는 타선의 진운동정보(진침로, 진속력)나 충돌회피정보(CPA, TCPA) 및 주위 상황 변화에 대한 다양한 물표 정보를 제공할 수 없는 문제가 있다. 따라서 본 논문에서는 이와 같은 문제에 주목하여 일반 소형 어선에 탑재되어 있는 저가형의 소형 레이더 장치로부터 analog video signal, trigger, bearing 및 heading pulse를 공급받아 현용의 자동 레이더 플롯팅 장치(Automatic Radar Plating Aid, ARPA) 레이더에서 제공하는 수준의 각종 정보를 정량적으로 추출 및 제공할 수 있는 레이더 목표 추출 장치(Radar Target Extractor, RTE)를 개발하여 소형 레이더 장치에 부착시켜 소형 연근해 어선에서도 타선의 진운동정보 및 충돌회피 정보와 같은 항해 정보를 수집, 활용할 수 있도록 하였다.

수협공제(水協共濟)의 보상제도(補償制度)에 관한 법적(法的) 연구(硏究) (A Legal Study on Indemnification of Korean Mutual Insurance of Fisheries Cooperatives)

  • 차철표;박용섭
    • 수산해양교육연구
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    • 제5권2호
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    • pp.98-109
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    • 1993
  • By the Article 28 of the Korean Fishing Vessels Act and the Article 47-1 of the Enforcement Ordinance of the Act, fishing vessels over 5 gross tone must be insured the fishing vessels mutual insurance or marine insurance. Therefore the distant-water fishing vessels and vessels registered with Classification Society can be insured to the marine insurance, and non-registered vessels and the small fishing vessels can be insured to the fishing vessels mutual insurance of Fisheries Co-operatives. Moreover, the shipowners of fishing vessels over 5 gross tons to be insured a liability insurance for their crew, and it is to compensate effectively the crewman's accidents prescribed in the Seaman's Act. The shipowner's Liability Insurance to be insured the seaman's Compensation Insurance or the seaman's mutual insurance of the Fisheries Co-operatives and the Protection and Indemnity but they still involve lots of problems to cover the crewman's accidents reasonably. The author's views on the improvement way of the fisheries mutual insurance system are as follows. 1. The size of fishing vessels over 5 gross tons prescribed by the Article 28 of the Fishing Vessels Act must be revised into over 1 gross tons. And the regulations concerning penalties against nonfulfilment of the regulation must be strengthened in order to have legal effectiveness. 2. The level of the government subsidy for the fisheries mutual insurance must be raised up from the large point of view for protection of fishermen. It is concluded that the Government have to take charge of the remutual insurance in order to develop the fisheries mutual insurance system. 3. The mutual insurance system of fish catch have to be executed in order to guarantee the stable income for fishermen on the base of the amount of money by fish catch in the previous year.

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어선 AIS에서의 하이브리드 GPS/EM 컴퍼스에 의한 선수방위 안정화 (Stabilization of ship's heading in AIS of fishing vessel by a hybrid GPS/EM compass)

  • 이유원;조현정;이대재
    • 수산해양기술연구
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    • 제46권1호
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    • pp.50-55
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    • 2010
  • The ship's heading information of hybrid GPS/EM compass were applied to the AIS of fishing vessel and examined the possibility of accuracy improvement. It is observed 453 each in AIS receiver of land among 3,982 each in AIS Rx/Tx transponder of the test ship at sea, and transmission interval according to the speed of ship is determined the 11.4% good transmitting data of the all information. In results, maximum compass error for the ship's heading of an EM compass was $19.1^{\circ}$. The variance of ship's heading owing to the speed of ship is surveyed. The COG (Course Over Ground) was changed extremely in $180^{\circ}W-179^{\circ}E$ range under 4.9knots, and in $24^{\circ}W-23^{\circ}E$ range over 4.9knots. Finally, using the ship's heading of EM compass and the COG from GPS for the autopilot system of a small fishing boat and the ship's heading information of AIS results in danger on the own ship's navigation safety and leads to make confusion both the others and VTS (Vessel Traffic Service) center. Therefore, the hybrid GPS/EM compass is identified as the best system for a small fishing boat and is allowed to offer continuously a ship's heading information with high accuracy and stability.

한국 주변해역 참조기의 자원생태학적 특성치 추정 (Estimations on population ecological characteristics of small yellow croaker, Larimichthys polyactis by the drift gillnet fishery in Korean waters)

  • 이종희;서영일;오택윤;이동우
    • 수산해양기술연구
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    • 제49권4호
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    • pp.440-448
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    • 2013
  • Estimations on population ecological parameters of the small yellow croaker, Larimichthy polyactis in Korean waters, were calculated using catch data based on coastal and offshore drift gillnet fishery and biological data from 2010 to 2012. The population ecological parameters included survival rate, instantaneous coefficient of natural and fishing mortality and age/length at first capture. The survival rate (S) of the small yellow croaker was estimated to be 0.20 from catch curve method. The instantaneous coefficient of natural mortality (M) was estimated to be 0.46/year with Alverson and Carney method. The instantaneous coefficient of total mortality (Z) was 1.611/year, used to be transformed the survival rate and the instantaneous coefficient of fishing mortality (F) were 1.153/year. The length at first capture ($L_c$) was 19.1cm by Pauly method, and the age at first capture ($t_c$) was 1.303 years of the small yellow croaker by the coastal and offshore drift gillnet fishery.