• 수산해양기술연구
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• 제55권1호
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• pp.7-19
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• 2019

This study was conducted in order to improve opening efficiency of the miniaturized small-scale net for anchovy boat seine gear to reduce the fleet size. Field experiment was performed to observe geometry of nets by catcher boats. When the distance between the two ships was 150, 300 and 450 m and the speed of towing nets was 0.6, 0.9, and 1.2 kt, the vertical opening and actual opening of each part of the miniaturized small-scale net was as follows: the front part of the wing net, 6.8-9.5 m, 45-63%; the middle part of the wing net, 16.1-30.7 m, 34-65%; the entrance of the inside wing net, 21.6-41.2 m, 44-84%; the square and bosom, 17.4-34.0 m, 38-75%; the entrance of the body net, 16.5-29.4 m, 36-64%; the entrance of the bag net, 14.5-21.9 m, 70-106%; the flapper, 6.7-7.7 m, 81-83%, and the end of the bag net, 8.6-10.9 m, 64-81%. The tension of towing nets was measured to be 2,734-6,812 kg approximately, which indicates that the fleet can tow nets with 350 hp, the standard engine horse power. The fishing operation time was shortened comparing to existent net with the large-scale buoy attachment operation. It was also possible to operate the ship without fish detecting boat.

• 한국수산과학회지
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• 제10권1호
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• pp.37-47
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• 1977

대서양 황다랭이(Yellowfin tuna)어업에 대한 최근의 자료를 국제대서양 참치 보존위원회(ICCAT)로부터 수집하며, 자원생물학적으로 분석하여 얻은 결과를 요약하면 아래와 같다. 1. 대서양에서의 상업적인 황다랭이 어업은 1955년에 시작되었으며, 한국은 1964년 연승에 의해 입어하기 시작하였고, 1972년 부터는 채낚기 어선도 출어하여 참치 어업이 이원화되었으나 아직은 연승에 의해 주로 어획하고 있다. 2. 대서양의 황다랭이 전체 어획량추이로 보면 어업이 시작된 이래, 연승어업의 portion이 극히 높았으나, 1966년부터 표층어업이 앞질러 1975년의 경우에는 전체 114.0천MT 중 연승은 25.5천 MT로 $23\%$에 불과하다. 그러나 한국은 연승어획국중에서는 1위를 마크하고 있다. 1. 대서양에서 황다랭이를 어획하기 위해 투입되는 모든 어획노력량을 연승의 낚시수로 환산한 바, 1974년의 경우 약 476백만 hooks 이었는데, 이중 연승은 163백만 hooks로 $34\%$이었다. 4. 황다랭이 어획량을 어획미수로 환산한바, 1973년에 8.6백만미로 평균 10.9kg짜리가 어획되었다. 5. 최근에 들어 오면서, 표층어업에서는 주군이 2세어군에서 1세어군으로, 그리고 연승에서는 3세어군에서 2세어군으로 야년화되어 가는 현상이 뚜렷했다. 6. 최근의 황다랭이의 평균 총사망계수(Z)는 1.5로 계산되었는데, 자연사망 계수를 0.8로 간주할 때 어획사망계수(F)는 0.7로 나왔다. 7. 1973년의 가입시 체중 계산은 2.7kg으로 나왔는데, 이는 ICCAT의 황다랭이 규제체중인 3.2kg 보다 훨씬 작다. 우리나라의 입장에서 볼 때, 연승은 별문제가 없으나 채낚기 어업의 경우, 이들 규제체중 미달어체의 혼획을 낮추는 문제를 조사${\cdot}$연구할 필요가 있다. 8. 가입량크기(Recruitment strength)를 비교한 결과, 강한 년급군의 가입량은 약한 년급군의 가입량에 비해 3배나 컸으나, 이들이 번갈아 나타나므로서 어획량에 미치는 영향을 최소화시켰다고 생각된다. 9. 대서양 황다랭이와 최대특속적 어획량은 95-145천 MT로 계산되었다. 이는 현재의 어획수준에 해당하는 값으로, 현재 이상의 어획노력의 투입은 오히려 어획량을 감소시키거나, 혹은 희망적인 경우라 할지라도, 잉여의 노력량 투입공에 해당하는 만큼의 어획량 증가는 어렵다고 생각된다. 10. 오늘날까지의 우리나라의 입장은 원양어업의 신장을 위해 어떠한 형태로 든지의 국제적인 자원규제조치를 부정적인 측면에서 받아들여 왔음이 사실이다. 그러나 최근의 연안국의 전관수역의 확산 움직임과 우리가 현재 사용하는 채낚기 및 연승의 선망에 비한 어법의 열세 및 어획량 portion의 상대적 감소등을 감안할 때, 적어도 표층어업과 연승별 어획량 quota 제의 실현이 장기적인 안목에서는 우리에게 안정적인 조업을 할 수 있는 길이 될것이라 생각한다.

• 해양환경안전학회지
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• 제24권6호
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• pp.810-817
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• 2018

우리나라에서 다랑어 선망어업은 국내 원양산업 중 업종별 생산량 1위의 업종으로, 1980년대 중 후반부터 연구가 지속적으로 수행되어왔으며, 기술의 현대화 연구가 활발히 진행되어왔다. 하지만, 어선에 탑재되는 보조작업선들은 원양어업에서 중요한 역할을 맡고 있음에도 관련 연구가 미흡한 실정이다. 이에 본 연구에서는 보조작업선들 중 네트보트의 추진기를 프로펠러에서 워터제트 형태로 변경하고, 그에 따른 선형 변환을 통한 선체 부가저항 감소 및 운항성능을 향상하고자 하였다. 이를 위해 전산수치해석을 통해서 선박의 유체성능 변화를 계산하였으며, 또한 기존 선형 및 추진기 변화 선형에 대해 모형선 수조시험을 수행하여 속도별 저항성능 비교를 수행하였다. 수치해석 및 1/7의 축소모형의 수조시험 결과, 기존의 네트보트 대비 45~58 % 저항성능이 크게 향상되었으며, 이는 철망 제거에 의한 단순 침수표면적 및 선형개선에 의한 저항성능 향상을 확인하였다.

• 수산해양기술연구
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• 제40권4호
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• pp.255-267
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• 2004

기선권현망어업의 어구 개량과 조업시스템 개선을 목적으로 자루그물을 A, B 2가지로 달리한 축소형 개량어구를 설계, 제작하여 현장조업선에 의한 해상실험을 실시하여 어구의 형상을 관찰한 결과를 요약하면 다음과 같다. 1. 축소형 개량어구의 실제 전개율은 오비기에서 20% 정도로 가장 작았고, 뒤쪽으로 갈수로 커지며, 자루그물에서는 110% 정도로 가장 컸으며, B형이 A형에 비하여 5~10%정도 크게 나타났다. 자루그물 입구와 뒤끝의 망고 변화폭은 A형이 9.0~13.6, 9.3·10.4m이고, B형이 10.9~14.8, 5.8~8.0m로 나타나서 B형이 A형에 비하여 자루그물 입구는 1~2m 크고, 뒤끝은 2~3m 작았다. 2. 축소형 개량어구는 오비기의 수직방향 전개성능이 개선되어 수비에 이르기까지의 예망수층이 완만하게 형성되었으며, 예망수층의 변화폭이 기존어구에 비해 적게 나타났다. 나발 그물이 포켓형상을 개선시켜 그물코의 날림현상 감소와 수비에서 자루그물까지의 어구형상이 완만하게 이루어졌으며, 예망속도가 느린 경우에도 어구의 형상이 안정되었다. 3. 축소형 개량어구 B형은 자루그물의 변화폭이 적었고, 이중깔대기의 부착으로 인해 입망된 어군의 도피율이 감소하였다.

• 한국해안해양공학회지
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• 제16권4
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• pp.224-232
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• 2004

지난 20여년간 다양한 공사가 시행된 금강하구에서 퇴적으로 인한 수로매몰을 분석하기 위하여 1988년부터 2000년까지 매 2년 간격으로 7가지 경우에 대해 단계별로 수치수동역학모형을 적용한 후측실험이 실시되어 바닥마찰응력의 변화와 상관된 퇴적율 평가가 실시되었다. 금강하구둑 건설로 최대마찰응력장이 약 $1-2N/m^2$ 에서 $0.2-0.6N/m^2$크게 줄어들고, 특히 1994년 금강하구둑의 수문 폐쇄 이후에 장항수로에서는 해저마찰응력이 한계마찰응력으로 제시된 $0.4N/m^2$ 이하로 급감하면서 퇴적환경으로 전이되고 있는 것으로 분석되었다. 하구둑건설은 금강 상류로 전파되는 조석에너지를 차단함으로써 조석수동역학의 급격한 변화를 초래하고 하구둑 전면에 퇴적환경이 급속도로 진행되는 직접적인 원인을 제공하고 있는 것으로 추론되었다. 소형어선의 통행지장을 겪는 장항수로의 매몰평가는 평균대조 조석을 적용하여 분석한 결과 기존에 비해 20% 이상 통행지장을 받는 것으로 평가되었다.

• 한국조경학회지
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• 제38권5_2호
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• pp.176-185
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• 2010

This study aimed to clarify meanings of Palkyung(八景) in different regions which can be considered as the prototype of the region's cultural landscape and also to confirm the change process by pointing out landscape characteristics and finally, to provide a foundation for the regions to establish their own identities, so they could be provided against the changes from developments in other areas. The relationship between the characteristics of landscape values and the components of 32 Palkyung in 4 places those are Gogunsan, Wido, Gunsan and Byunsan under Saemankeum area have been analyzed and evaluated from operational point of view to clarify the structure of the landscape concept. Some important differentiation points would be the sunset of the West Sea, sailing boats and the sceneries related to fishing as they are in the West Sea Islands and the coastal regions; and it clearly reflects the local customs and the characteristics of the landscapes. Each of Gogunsan, Wido and Gunsan Palkyung has 2 distance views with 4km of visible area while Byunsan Palkyung has only 1; and it is considered that because it is mountain area. Most of the Byunsan Palkyung has close range views except for Seohaenakjo and there are around 4 close range views in other areas. There were 4 landscape dominated influence areas each in Gunsan and Byunsan, which means that there are comparatively more close to middle range views. Moreover, each region contains 2 to 3 views of psychological influence but as mentioned, Byunsan has only 1 view of psychological influence. Therefore it is very important and valuable thing to consider the scenic relationship, preservation and reconstruction of Palkyung when planning the project.

• 수산경영론집
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• 제27권1호
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• pp.15-45
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• 1996

The sustained economic growth cannot be expected without the balanced development in all the realms of industries. Korea has recorded the continuous high growth rate of economy, but it is now facing some difficulties in keeping the normal economic growth, because industrial workers do not like to work in some fields, the typical one of which is the fishery works. This thesis aims at studying the determinants of fishermen's job satisfaction(FJS) and the determinants of affecting the fishermen's trunover intention(FTI) to obtain and maintain the man power for fishing boats. This study assumes that the determinants which affact FJS are fishermen's work values, job characteristics, the attitude of accepting their fishery work, and that the determinants which affect FTI are FJS and their perceptions of labor market. This study concerns two kinds of Job satisfaction : one is an intrinsic satisfaction which comes directly from the work itself, and the other is an extrinsic satisfaction comes from the compensation for the work, but in this study “Pollnac's work satisfaction factor” is added as an additional determinant of FJS. There is a difference in job satisfactions between the individuals who have different work values. Some feel more satisfacttion than the others, which can be explained by the internal work values which assume the work is only a means for another objective of life. This study applies Hackman and 014ham's studies to the job characteristics that a worker's job satisfaction is positively related to the core job characteristis of the job. In addition, this study transformed their studies into variables. A job enrichment to reduce the simplicity of a work and make it more valueable can increase a job satisfaction, but an existing organization has limitation in redesigning the job for its enrichment. A reasonable answer about this matter can be obtained from the workers' subjective perceptins to highly regard the objective job characteristics. Worker's previews of fishery work also affect their job satisfaction because they are already informed of the details and charcteristics of the job that they have to carry out. A Job dissatisfaction causes their intention to leave jobs owing to general perceptions prevailing in labor markets.

• Journal of Advanced Marine Engineering and Technology
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• 제18권5호
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• pp.56-67
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• 1994

The installation methods of diesel engines in ships would be largely classified into two groups : one is the direct mounting system fixing engine directly into double bottom of the hull, and the other is the resilient mounting system having vibration absorbers between engine and ship body such as rubber plate to prevent shocks or vibration transmission. The direct mounting system is generally used for large-sized low speed diesel engines, because the resilient mounting system has difficulties in reducing the natural frequency of engine itself under normal speed. On the contrary, the resilient mounting system is often used for medium or high speed engines for marine propulsion and generator that have light weight and high revolution speed. Recently, it is even applied to engines having relatively low speed(300-400rpm) for fishing boats. Although many researches for the resilient mounting system have been carried out, many problems in applying these results directly to marine vessels because most of these have been used for automobiles. Up to now we have had to depend on the professional foreign company in design and the supply of parts for the resilient mounting system of marinediesel engines utterly. In preseut study, the exciting forces of engines effecting to resilient mounting were examined, and patterns of vibration and evaluation procedure for force transmission from resilient mounting to the body of hull were established. Also, these results were applied to the analysis of free and forced vibration for the rubber-type resilient mounting systems of marine diesel engines. Besides, after changing the various design parameters, such as locations, angles, dynamic characteristics and the number of resilient mountings, the influences on resilient mounting system were also examined.

• Strategy21
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• 통권43호
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• pp.175-199
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• 2018

Recent marine territorial disputes in the East China Sea and the South China Sea have come to us as a great threat. China, which has recently established the China Coast Guard and has rapidly developed maritime security forces, is trying to overcome the various conflict countries with its power. Japan is also strengthening intensively its maritime security forces. Since Korea, China, and Japan are geographically neighboring and sharing maritime space in Northeast Asia, there is no conflict between maritime jurisdiction and territorial rights among the countries. The struggle for initiative in the ocean is fierce among the three coastal nations in Northeast Asia. therefore, Korea needs more thorough preparation and response to protect the marine sovereignty. As the superpowers of China and Japan are confronted and the United States is involved in the balance of power in strategic purposes, the East Asian sea area is a place where tension and conflict environment exist. China's illegal fishing boats are constantly invading our waters, and they even threaten the lives of our police officers. The issue of delimiting maritime boundaries between Korea and China has yet to be solved, and is underway in both countries, and there is a possibility that the exploration activities of the continental shelf resources may collide as the agreement on the continental shelf will expire between Korea and Japan. On the other hand, conflicts in the maritime jurisdictions of the three countries in Korea, China and Japan are leading to the enhancement of maritime security forces to secure deterrence rather than military confrontation. In the situation where the unresolved sovereignty and jurisdiction conflicts of Korea, China and Japan continue, and the competition for the strengthening of the maritime powers of China and Japan becomes fierce, there is a urgent need for stabilization and enhancement of the maritime forces in our country. It is necessary to establish a new long-term strategy for enhancing the maritime security force and to carry out it. It is expected that the Korean Coast Guard, which once said that it was a model for the establishment of China's Coast Guard as a powerful force for the enforcement of the maritime law, firmly establishes itself as a key force to protect our oceans with the Navy and keeps our maritime sovereignty firmly.

• 수산경영론집
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• 제8권2호
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• pp.1-19
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• 1977

The results analyzed of the actual state of medium size two-boat trawler fishery based on the cost expended in 1975 are as follows: According to the calculation of interest, the total cost of this fishery comes to ￦ 55,353,807, and in this account, the production cost comes to ￦ 49,747,383 (89.9%) and the material cost comes to ￦ 27,027,662(48.8%), the labour cost comes to ￦ 10,381,013 (18.8%) the expenses, ￦12,338,708(22.3%) and commision and interest comes to ￦ 5,606,424 (10.1%). As above the fishery comes is 90% of production cost for the expense of production. The ratio of cost element to the total cost 100 is as follow: Fuel: 23.6%, allocation: 14.3%, fishing gear: 14.1%, boat repair: 13.0%, fish box: 8.5%, ice: 14.1%, commission: 6.9%, food cost: 4.5%, interest: 3.2%, transportation fee: 2.8%, consumption: 2.6%, tax: 2.5%, depreciation: 2.4%, administrative expense: 1.6%. The unit cost of catches to each box, including the interest, cames to ￦ 2,167 and not calculating the interest it comes to ￦ 2,098. The cost production to each kg comes to ￦ 114 including interest, without interest, it comes ￦110. When the production cost comes to 90.6%, it comes to 9.4% of total revenue. The reason which this fishery brings low income is that the boats are almost old and semi-diesel engine is used. So, fuel expense and repaire expenses needs too much. Acconding to above this fishery needs to replace new boat and new engine. And new are for this fishery needs to bring under cultivation in order to bring good income with the new method for this fishery. Specially, this fishery brings low income from July to September because of its rest from labour. And so, the expenses, item, and account of money, and the trust money the cost element are not showed in August.