• 대한기계학회논문집A
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• 제34권11호
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• pp.1779-1784
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• 2010

어업 분야에서 그물세척 작업은 엄청난 노동력과 작업시간을 요구하며 심한 환경 오염을 발생시킨다. 본 연구에서는 그물 양망 기능과 세척 기능, 그물펴짐 기능을 동시에 갖춘 그물세척용 양망기를 개발하였다. 양망회전체의 구조를 개선하여 구조물의 안정성을 높이고 대형 그물의 양망 중에 발생할 수 있는 그물 슬립 문제를 해결하였다. 양망기에 세척 기능을 부가하여 그물자동세척기를 이용한 최종 세척 전 단계에서 1 차 세척을 수행하거나 중소형 그물의 주 세척 작업에 세척용 양망기를 사용할 수 있도록 하였다. 대형 그물 세척을 위한 그물자동세척기의 세척 효율을 높이기 위하여 양망기 하단에 그물펴짐보조대를 설치함으로써 양망기로부터 접힌 채내려오는 그물을 펴는 작업이 용이하도록 양망기를 설계하였다. 시작품을 제작하여 그물 세척 실험을 수행한 결과, 양망 중에 그물슬립을 완벽히 방지할 수 있었고 양망기의 1 차 세척 기능에 의하여 그물 펴는 작업의 수월함을 확보함으로써 작업 효율과 세척 효율을 대폭 향상시킬 수 있었다.

• 수산해양기술연구
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• 제38권2호
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• pp.172-178
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• 2002

본 연구는 유체역학적 해석을 이용하여 선망 어구 운동을 동적으로 시뮬레이션하였다. 선망 어구는 조업 과정 중에 어구의 형상이 크게 바뀌는 특성이 있고, 모든 조업단계에서 어구요소가 3차 시스템이며 대부분 망지라는 유연한 물체에 의해 구성되어 있어 외력에 대해 그 형상이 비선형적으로 변하므로 모델링이 어렵다. 본 연구에서는 질량-스프링 모델을 이용하여 수학적으로 기술하였다. 선망의 조업 과정중 그물의 투망, 침강, 죔줄을 죄는 과정의 어구운동을 시뮬레이션하였다.

• 수산해양교육연구
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• 제24권2호
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• pp.137-145
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• 2012

In order to survey the conditions of bycatch and discards for a gape net, a series of filed surveys was carried out total 10 surveys on two gape nets operated in the coastal area of Jindo during July to November 2008. The all catches in each survey were measured the body length, weight after sorted species. The analysis of catch data was conducted to separate 'first operation' and 'general operation'. In this study, the first operation defined as hauling the fishing gears that soaked over 10 hours because of setting on the previous day. The general operation means the haul of fishing gears conducted at intervals of one of or two hours after first operation. The bycatch in this study is defined as the other species except for anchovy, and bycatch rate refers to the proportion of bycatch to total catch. From the survey results, the average bycatch rates on first operations were 50% and 51% for Masa-ri and Supum-ri areas in Jindo, respectively. Also, the average bycatch rates on general operation were 2% and 3% for Masa-ri and Supum-ri areas in Jindo, respectively. The proportion of anchovy to total catch caught represented 75.5%. It needs the research on the selective fishing technology to reduce the bycatch on the gape net fishery.

• 수산해양기술연구
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• 제57권1호
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• pp.57-68
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• 2021

In order to collect basic data for the improvement of fishing systems in coastal improved stow net fishery, a questionnaire survey and on-site hearing were conducted from May 10 to June 11, 2019 on the basic items of coastal improved stow net fishery and safety accidents that occurred during fishing operation. The questionnaire for the survey on the actual conditions of coastal improved stow net fishery consisted of a survey on basic matters (six questions) and a questionnaire (six questions) on safety accidents occurring during fishing operation. The results of the survey on basic items were analyzed by region (Incheon, Seocheon, Gunsan and Mokpo), by the captain's age (less than 50 years of age, 50 to 60 years and more than 60 years of age), by the captain's career (less than 20 years, 20 to 30 years, 30 to 40 years and more than 40 years) and by the age of fishing vessel (less than 10 years, 10 to 20 years and more than 20 years). According to the survey on basic items of coastal improved stow net fishery such as the captain's age, the captain's career, the age of fishing vessel, the fishing nets in use, the crews on board and the operation days per voyage by region, the average captain's age was 55.7 years, the average captain's career was 20.5 years, the average age of fishing vessels was 9.0 years, the average numbers of nets used by fishing boats was 14.0 sets, the average numbers of crew on board a fishing boat was 4.4 persons and the average numbers of operation days per voyage was 4.9 days (p < 0.05). As a result of the survey on safety factors during fishing operations, such as experience of ship accidents, major causes of ship accidents experienced, causes of ship accidents (first priority), experience of human accidents, major causes of human accidents, and causes of human accidents (first priority), more than 96% of the respondents experienced ship accidents including collisions with other vessels or fishing gear during fishing operations. The most significant cause of the accident was the other's fishing gear installed in the fishing grounds. The first possible causes of ship accidents during fishing operations were found to be other fishing gear installed in fishing grounds, steering or engine failure, and inability to avoid accidents during casting and hauling nets. The survey of the experience of human accidents, such as injuries or sea falls, showed that more than 90% of the respondents experienced human accidents during fishing operations. The most important cause of accidents experienced during fishing operations was stucked in a fishing gear during casting and hauling nets. The first important causes of accidents during fishing operations were movement of the fishing gear during casting and hauling nets, damage of the fishing gear such as rope cutting. The results are expected to be provided as a basic data to prevent safety accidents occurring during fishing operation and improve the fishing system in the coastal improved stow net fishery.

• 수산해양기술연구
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• 제31권4호
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• pp.350-361
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• 1995

본 논문은 1994년 8월 1일부터 10월 5일 사이에 대변항을 중심으로 조업하고 있는 근해 멸치유자망 어선의 멸치유자망 표류상태를 측정하기 위하여 멸치유자망에 GPS 3개를 설치하여 유자망의 흐름을 측정하고, 조류계로 유향.유속을 측정하여 어구의 표류상태와 이들 상호간의 관계에 대해 검토, 분석하였다. 그 결과를 요약하면 다음과 같다. 1) 육상 고정점에 대한 GPS의 95% 확률원 오차는 대변항에서 79.8m였고 표준위치로부터 평균편위거리는 21.0m였다. 2) 대변항에서 GPS의 PDOP와 HDOP의 평균값은 각각 3.5, 1.9로서 비교적 안정된 측위를 얻을 수 있음을 알 수 있었다. 3) Lat $35^{\circ}$ 41.5'N에서 $35^{\circ}$ 43.5'N, Long $129^{\circ}$ 30.1'E에서 $129^{\circ}$ 31.2'E 사이의 어장에서 그물의 뻗친 방향은 $190^{\circ}$ 였고 투망이 완료된 시점네서 전체 어구의 방향은 $200^{\circ}$ 였다. 양망 당시 어구의 전개된 형태는 직각으로 휘어진 모양이며 투망 완료 후 양망이 시작될 때까지 그물 전체는 $170^{\circ}\;~\;180^{\circ}$ 방향으로 표류하였다. 평균표류속도는 0.82kt였다. 4) Lat $35^{\circ}$ 44.0'N에서 $35^{\circ}$ 45.2'N, Long $129^{\circ}$ 33.0'E에서 $129^{\circ}$ 34.0'E 사이의 어장에서 그물을 뻗친 방향은 $20^{\circ}$ 였으며, 투망 완료시 어구의 전개는 $20^{\circ}$ 방향이고 양망 당시 어구의 전개된 형태는 N에서 S로 바뀌었는데, 투망 완료후 양망이 시작될 때까지 평균적으로 210~220$^{\circ}$ 방향으로 표류함을 알 수 있었다. 평균표류속도는 0.75kt였다. 5) Lat $35^{\circ}$ 44.9'N에서 $35^{\circ}$ 46.0'N, Long $129^{\circ}$ 34.0'E 사이의 어장에서 그물 뻗친 방향은 $35^{\circ}$ 였으며, 투망 완료된 어구의 형태는 $50^{\circ}$ 였고 양망 시작시 그물의 방향은 E에서 S방향으로 바뀌었다. 그물은 $330^{\circ}\;~\;340^{\circ}$ 방향으로 표류하였다. 평균표류속도는 0.63kt였다.

• 수산해양기술연구
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• 제43권1호
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• pp.12-27
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• 2007

This fundamental studies on for the productivity improvement and laborsaving of purse seine fishery. Given the difficulty posed from the distortion of net shape caused by the external forces, such as tide, at the time of shooting and pursing, we set the 4 steps of 0, 2, 4 and 6cm/sec in flow velocity in the flume tank for the experiment in order to examine those characteristics. We used two model seines designed on the scale of 1 to 180 based on the power block seine, which is the mackerel purse seine generally used in the near sea of Jeju Island and triplex seine, which is the mackerel purse seine of one boat system fishing expected in the future, for the experiment, and interpreted the characteristics of several motion in water, such as the shape of seine, the change in tension and area during pursing and its the analysis results are as follows. Though the experiment could be conducted up to 6cm/sec of flow velocity that was defined, the experiment could not go on because of the severe distortion in the seine at the flow velocity in excess of 6cm/sec. As for the depth of leadline and reduction rate of side area of seine when the pursing is connected, P seine turned out to be slightly higher than T seine, and the hauling speed and reduction rate of upper area of seine were found similar to each other. The correlation between the hauling time (Ht) and depth of lead line (Dhp, Dht) of P seine and T seine can be expressed by the equation, that is, Dhp=(0.99Pt-7.63)Pt+69.01, Dht=(1.03Pt-7.73)Pt+66.74. The correlation between the hauling time and hauling velocity (Hpp, Hpt) can be expressed by the equation, that is, $Hpp=-0.06Ht^2+0.88Ht+0.78,\;Hpt=-0.05Ht^2+0.81Ht+0.98$ here, Pt is pursing time. And the correlation between the pursing time and the reduction rate of side area (sArp, sArt) can be expressed by the equation, that is, $sArp=-0.48Pt^2+14.79Pt-16.74,\;sArt=-0.45Pt^2+14.56Pt-16.48$. The reduction rate of upper area of seine (tArp, tArt) can be expressed by the equation, that is, $tArp=0.34Pt^2-0.66Pt-0.74,\;tArt=0.34Pt^2-0.27Pt-1.80$. In addition, the correlation between the pursing time and tension of purse line (Tep, Tet) can be expressed by the equation, that is, $Tep=2.79Pt^2+2.26Pt-0.60,\;Tet=2.14Pt^2+8.08Pt-27.50$.

• 한국수산과학회지
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• 제2권2호
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• pp.173-178
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• 1969

(1) 1968년 6월 18일부터 7월 16일 사이에 일본수산청 어업조사선 Kaiyo-Maru에 승선 New Zealand 근해에서 trawl 실험을 행하였다. (2) 대형선미 trawl에 있어 예강초와 양강직전의 warp 장력간의 차는 입강어의 다과와는 상관이 없는 것 같다.

• 수산해양기술연구
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• 제54권4호
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• pp.271-278
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• 2018

In this study, the conventional cylinder-shaped lower bar on the canvas was modified and its performance was tested to improve the opening force of the stow net on anchor. The improved new lower bar used in the test is consisted of 13 flat bars with a length of 1.8 m, a width of 0.075 m and a thickness of 4 mm, and a pipe with a length of 2.0 m and a diameter of 50 mm. A stow net with the improved lower bar and a stow net with an existing lower bar were installed underwater and their trajectories for 21 hours were examined. To confirm their trajectories, GPS loggers were attached to the buoys on the left and right canvases and the buoy of the hauling rope. As a result of the test, the rotation of the gear with the improved bar was smoother than that with the existing bar. As a result of comparing the changes in the interval of the buoys attached to the canvas after the low and high tide, the buoy spacing of the gear with the improved bar is wider than that of the conventional gear; moreover, the larger the interval, the smoother the rotation of the fishing gear was. Therefore, it is considered that using the improved lower bar can enhance the performance of the stow net.

• 수산해양기술연구
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• 제57권4호
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• pp.316-333
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• 2021

In order to understand basic data for improving the fishing system and fishing vessel structure in coastal improved stow net fishery, a questionnaire survey and on-site hearing were conducted from May 10 to June 11, 2019 to analyze opinions on the improvement of operation status and fishing vessel structure. The questionnaire survey consisted of ten questions on the operation status of coastal improved stow net fishery and six questions on the improvement of fishing vessel structure, and the results of each question were analyzed by the region, the captain's age, the captain's career and the age of fishing vessel. As a result of analyzing opinions on the operation status of the coastal improved stow net fishery, it was found that the average time required for casting net was 32.8 to 33.0 minutes and that the average time required for hauling net was 41.0 to 42.2 minutes which took 10 to 12 minutes more than for casting net. The most important work requiring improvement during fishing operation (the first priority) were 'hauling net operation,' 'readjustment and storage of fishing gear,' and 'fish handling' and the hardest factor in fishing management were in the order of 'reduction of catch,' 'labor shortage' and 'rising labor costs.' The most institutional improvement that is most needed in coastal improved stow net fishery was an 'using fine mesh nets.' Most of the respondent to the questions on the experience in hiring foreign crews was 'either hiring or willing to hire foreign crews,' and the average number of foreign crews employed was found to be 2.3 to 2.4 persons. The most important reason for hiring (or considering employment) foreign crews was 'high labor costs.' The degree of communication with foreign crews during fishing operation were 'moderate' or 'difficult to direct work.' The most important problem in hiring foreign crews (the first priority) was an 'illegal departure.' As the survey results on the opinion of structural improvement of coastal improved stow net fishing vessel, the degree of satisfaction with fishing vessel structure related to fishing operation was found to be somewhat unsatisfactory, with an average of 3.3 points on a five-point scale. The inconvenient structure of fishing vessel in possession (the first priority), the space needed most for the construction of new fishing vessel (the first priority) and the space considered important for the construction of new fishing vessel (the first prioprity) was a 'fish warehouse.' The most preferred equipment for the construction of new fishing vessel were 'engine operation monitoring' and 'navigation safety devices.' The average size (tonnage class), the average horse power and the average total length of fishing vessel for proper profit and safety fishing operation was between 13.8 and 14.0 tonnes, 808.3 to 819.5 H.P. and 23.4 to 23.5 meters, respectively. The results of the operation status of coastal improved stow net fishery and the requirement for improving the fishing vessel structure are expected to be provided as basic data for reference when we build or improve the fishing vessel.

• 수산해양기술연구
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• 제60권2호
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• pp.152-160
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• 2024

We analyzed risk factors of coastal gillnet fishers during fishing process and considered work safety measures to reduce safety accidents during fishing using a UWB (ultra wideband) based positioning system. The static position accuracy of the UWB based positioning system was 45 cm. When entering a port, there is a risk of falling overboard. When casting a net, there was a risk of falling overboard due to being hit by fishing gear or guards, or getting caught in a buoy line or sinker line. When hauling a net, there is a risk of getting caught between fishing gear and net hauler, and the risk of musculoskeletal disorders due to repetitive work over a long period of time. Most safety accidents during work on fishing boats are blamed on human errors of the fisher and skipper, but safety accidents occur due to a mixture of mechanical and equipment factors, work and environmental factors, and management factors in addition to human errors. Therefore, the 4E were presented as countermeasures against the 4M, which are causes of safety accidents, and the proposed measures were used to identify risk factors for operation process, comply with work safety rules, and ensure the wearing of personal protective equipments. We need to reduce safety accidents during work by making it part of our daily routine. These research results can be used in the future for optimal placement of fishing gear and fishing nets in other coastal industries where safety accidents occur frequently.