• 수산해양기술연구
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• 제35권3호
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• pp.243-249
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• 1999

Specificity of catches has been analyzed to japanese tuna purse seine A principle component analysis was used to improve the efficiency of fishing and increase sustainable production and productivity of Korean tuna purse seine.The result are as follows;From the principal component analysis of the fish catches, the first principal component(Z1) to promote principal component score was skipjack Kastsuwonus Pelamis, LINNAEUS and yellowfin tuna Thunnus Albacares, BONNATERRE (Small : smaller than 10kg) and proportion was 86.8% of total. The second principal component(Z2) to increase principal component score was yellowfin tuna (Large : larger than 10kg) and proportion was 9.5%.On the other hand, fish operating that have caught skipjack and yellowfin tuna (Small and Larger) was not so much. Fish catches for one species raised volume of the catches while catches for multi-species decreased it since principal composition score for one species and both species together has been increased.Fish school could be divided into three groups of schools each of which was associated with drift objects, payaho and ship, school associated with shark, whale and porpoise and school of breezing, feeding and jumping from proportion of principal component analysis for fish catches of school types. However, the biological pattern is different among school associated with ship, payaho and school associated with drift objects for analysis eigen vector. School associated with ship, payaho and school associated with drifting object associated is judged as school which be assembled to vessel and drifted log temporary.

• 수산경영론집
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• 제29권2호
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• pp.163-175
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• 1998

The decrease of the fishery's business performance is due to the changes of environment-the increase of cost, the reduction of resources, the liberalization of import, the effectuation of the admiralty law Though the government has prepared the alternative policy to strengthen the competitive power of the fishery, fishermen should draw up a plan to improve the business performance. The problems of the small powered purse seine resulting from the small scale of the fishing boat is following. First, its catching activity in the sea is riskful. Second, the space to eat and to work is not enough. Third, the space to put the fish is not enough, it is hard to maintain the freshness of the fish. Therefore it is necessary to solve these problems for the scale of the fishing boat to have to be enlarged. The enlargement of the fishing boat to be required much expenditure of fund is the important investment decision to fishermen. The alternatives evaluation between the existing boat(defender) and the new boat enlarged with the new equipment(challenger) is necessary process to reduce the uncertainty of investment. The profitability of the challenger is better than that of defender due to the reduction of cost and the increase of revenue. Because the net present value of incremental cash flow is positive, it is rational for fishermen to accept the challenger.

• 수산경영론집
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• 제43권1호
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• pp.11-18
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• 2012

This study is aimed to estimate a dynamic productive efficiency by vessel of large purse seine fishery and analyze changes of them over times using a window/DEA method. In addition, based on estimation results, it aims to suggest production management implications for an viable development of fisheries. Results indicated that an annual efficiency change of large purse seine fishery was estimated at 0.77 for 2007~2008, 0.83 for 2008~2009, and 0.77 for 2009~2010, showing a decreasing trend. As returns on sales of vessels of large purse seine fishery showed a decreasing trend, the degree of efficiency of a vessel might be closely related to the fishing profitability. The Window/DEA method was used in this study to estimate the efficiencies of vessels for large purse seine fishery. This method is well known and widely used to analyze the dynamic efficiency and it can provide useful implications for management of input factors. As a limitation of this study, it was not able to provide detailed management ways to reduce inefficiencies. However, they can be investigated with data on managerial factor, human factor, distribution factors as a future study.

• 수산경영론집
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• 제44권2호
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• pp.83-100
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• 2013

This survey was conducted with crewmen on large purse seines in order to increase satisfaction of crewmen. The degree of fulfillment of internal marketing on crewmen (internal communication, empowerment, welfare benefits, management support, and reward system), satisfaction of crewmen, turnover intention, recommendation intention and need for achievement were examined. 200 surveys were distributed and 150 surveys were returned, among which insincere responses were excluded to analyze 146 responses. The results are as follows. First, factors of internal marketing that influence satisfaction of crewmen include empowerment, welfare benefits, and reward system. Second, turnover intention was reduced and recommendation intention was increased with increasing satisfaction of crewmen. Third, while need for achievement moderated the relationship between satisfaction of crewmen and turnover intention, it did not moderate the relationship between satisfaction of crewmen and recommendation intention. In other words, stronger need of crewmen for achievement causes greater negative(-) effect of crewmen's satisfaction on turnover intention.

• 수산해양교육연구
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• 제21권3호
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• pp.373-389
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• 2009

The aims of this study are to examine urgent problems for reorganization into future-proof large purse seine fisheries in order to positively cope with rapidly changing domestic and foreign fisheries circumstances. First, this paper provides current situations of the large purse seine fisheries. The current situations of it are composed of fisheries influence such as vessel number, vessel power, and fisher number, use of resource and fishing places, and changes in products and sales of species caught by the large purse seine. Secondly, this paper reviews current problems of the large purse seine fisheries including cost reduction and increase of value added. Thirdly, this paper suggests basic development direction and countermeasures for strengthening competitiveness of the large purse seine fisheries. In conclusion, urgent problems of the larger purse seine fisheries can be summarized as inefficiency of distribution structures and retarded landing system and facilities as well as the worse of profitability according to shrink of fishing places, reduction of products, lack of workers, and increase in oil price. To solve the urgent problems, the large purse seine fisheries should be changed into an industry with low cost and high efficiency, and also need to introduce of new production system, strengthen autonomous management of natural resource, and increase in value added to products.

• 한국어류학회지
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• 제35권2호
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• pp.113-120
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• 2023

이번 연구에 사용된 고등어는 2022년 1, 3~5, 7~9, 11월에 제주도 주변 해역에서 대형선망, 소형선망어업에 의해 어획된 959개체를 이용하였으며, 전장(Total length)과 체중(Body weight)을 각각 0.1 cm와 0.1 g 단위까지 측정한 뒤, 위를 적출하여 먹이 생물의 크기와 무게를 측정하고 가능한 종 수준까지 분석하였다. 위내용물 분석 결과는 상대중요도지수비를 이용하였으며, 계절과 크기군에 따른 먹이조성 변화를 알아보았다. 고등어의 가장 중요한 먹이생물은 난바다곤쟁이류(Euphausiacea)였으며, 그 다음으로 중요한 먹이생물은 어류(Pisces)로 나타났다. 그 외에, 단각류(Amphipoda), 요각류(Copepoda), 새우류(Caridea), 게류(Brachyura), 두족류(Cephalopoda) 등이 출현하였으나, 0.8% 이하의 상대중요도지수비를 보여 그 양은 매우 적었다. 계절별 위 내용물 조성을 살펴본 결과, 봄, 여름, 가을철에는 난바다곤쟁이류를 주로 섭식하였으며, 여름철에 비율이 가장 높게 나타났다. 겨울철에는 어류가 가장 중요한 먹이생물로 나타났다. 또한 크기 군별 위내용물 조성을 알아본 결과, 모든 크기군에서 난바다곤쟁이류가 가장 우점하였으나, 성장함에 따라 난바다곤쟁이류의 비율은 감소하고 어류의 비율이 증가하는 경향을 보였다. 고등어는 성장함에 따라 개체당 평균 먹이생물의 개체수는 통계적으로 유의한 차이를 보이지 않았으나, 먹이생물의 중량은 통계적으로 유의한 차이를 나타냈다.

• 수산해양기술연구
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• 제53권2호
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• pp.169-176
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• 2017

Tuna purse seine fishery in the western and central Pacific Ocean (WCPO) has been rapidly developed since early 1980s due to massive investment of major distant water fishing nations, and catch by purse seine fishery operating in the WCPO accounts for nearly half of the world's tuna total catch. As fishing efficiency is reflected by not only improving of individual vessel's capacity but also increasing number of active vessel, it is essential to understand vessel capacity for reliable assessment result on how fishery affects stock status of target species. In this study, fishing efficiency was analyzed by main factors which are representative of vessel capacity using fishing data and vessel information related to Korean tuna purse seine fishery operating in the western and central Pacific Ocean from 1992 to 2014. It showed that fishing efficiency of vessel tends to be higher when having larger vessel tonnage, higher engine power, lower vessel age and larger length of vessel. As for fishing efficiency by set type, CPUE of associated set with floating objects was generally higher than that of free school set, and CPUE of free school set seemed to have a greater effect on engine power and vessel age compared to other factors.

• 수산해양기술연구
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• 제54권2호
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• pp.116-123
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• 2018

Pacific bluefin tuna (Thunnus orientalis) has been mostly caught by the Korean offshore large purse seine fishery in Korean waters. The annual catch of Pacific bluefin tuna caught by the offshore large purse seine fishery in Korean waters showed less than 1,000 mt until the 1990s except for 1997. The catch sharply increased to 2,401 mt in 2000 and recorded the highest of 2,601 mt in 2003, but the catch has generally decreased with a fluctuation thereafter. The main fishing ground of Pacific bluefin tuna of this fishery is formed around Jeju Island. However, it expanded to the Yellow Sea, the coastal of Busan, and the East Sea, which depends on the migration patterns of Pacific bluefin tuna by season. The CPUE standardization of Pacific bluefin tuna was conducted using Generalized Linear Model (GLM) to assess the proxy of the abundance index. The data used for the GLM were catch (weight), effort (number of hauls), catch ratio of Pacific bluefin tuna, moon phase by year, quarter and area. The standardized CPUE from 2004 to 2011, except for 2003 and 2010, showed a steady trend, and then increased until 2014. The CPUE in 2015 decreased, and in 2016 was higher than that in 2015. The result of GLM suggests that the effect of the catch ratio of Pacific bluefin tuna is the largest factor affecting the nominal CPUE.

• 수산해양기술연구
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• 제47권4호
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• pp.369-389
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• 2011

Changes in ecosystem risks were evaluated using the ecosystem-based fisheries assessment (EBFA) approach of Zhang et al. (2009, 2010) and the comprehensive ecosystem-based fisheries management (EBFM) plan was made for the southern sea of Korea in this study. The risk assessment of the southern sea ecosystem was conducted by establishing ecosystem management objectives and by estimating risk scores (RS) for indicators. To conduct this analysis a number of indicators and their reference points for assessing these risk scores were developed in this study. The number of indicators in the risk analysis was 28 for the quantitative tier 1 analysis and 30 for the qualitative tier 2 analysis. The objective risk index (ORI), species risk index (SRI) and fisheries risk index (FRI) were calculated from the risk scores. Comparing the past (1988) and the current (2008) status of fisheries resources, management implications were discussed. The fishery risk index (FRI) of large purse seine fishery in the southern sea of Korea decreased substantially from 0.972 in 1988 to 0.883 in 2008, and improvement in the management of fisheries operated in the southern sea of Korea.

• 수산해양기술연구
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• 제53권1호
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• pp.12-18
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• 2017

Lots of fishery stocks are overexploited and the overcapacity exists in Korean fishing fleets. One of the reasons is technological development, which increases the efficiency of the vessels continuously. The analysis was conducted to identify the change of fishing power index to develop the vessel and gear technology that may have improved the fishing efficiency of the offshore large powered purse seine fishery from 1960s to 2010s. Gross tonnage and horse power per fishing vessel was increased annually. Fishing gear material was changed to the knotless webbing to settle faster. Fishing equipments was modernized and supply rate was also increased. Therefore the relative fishing power index in the offshore large powered purse seine fishery increased from 0.4 in 1970 to 1.0 in 1980, to 1.5 in 2000 and to 1.6 in 2010, but the rate of increase slowed down gradually. The results are expected to contribute to reasonable fishery stock management.