• 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.

• Ocean and Polar Research
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• 제39권3호
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• pp.195-203
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• 2017

The purpose of this paper is to estimate the optimal $CO_2$ emission in the maximum economic yield (MEY), maximum sustainable yield (MSY), and open access (OA) using a bioeconomic model. The results are as follows; in the case of $E_{MEY}$, $E_{MSY}$, and $E_{OA}$ levels, $CO_2$ emissions are estimated at $150,704,746CO_2/kg$, $352,211,193CO_2/kg$, and $301,409,492CO_2/kg$ respectively. We show that the $E_{MEY}$ is more efficient than the other levels. That is, the level of $E_{MEY}$ signifies the optimal economic fishing usage as the most economically efficient usage for large purse seine fishery catching mackerel species. The emission of $CO_2$ in $E_{MEY}$ is the lowest level. Also, the impacts of climate changes such as ocean temperature increase, ocean acidification, and the combined impact thereof show that the biomass of mackerel decreases.

• 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.

• 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.

• 수산해양기술연구
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• 제52권2호
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• pp.149-161
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• 2016

Fishing characteristics of Korean tuna purse seine fishery in the Pacific Ocean were investigated using logbook data compiled from captain onboard and the statistical data from 1980 to 2014. Changes in fishing ground and correlation between marine environmental factors and fishing patterns were investigated using Oceanographic index. The proportion of unassociated set was higher than that of associated set. The catch proportion of yellowfin was higher in the unassociated set, while that of skipjack and bigeye was higher in the associated set. Due to vessels, fishing gears and Korean captains' high-level of skills in fishing technology optimized for the unassociated set and preference of large fishes, especially large yellowfin tuna, it showed unique fishing characteristics focusing on the unassociated set. As for fishing distributions of Korean tuna purse seine fishery and impacts of oceanographic conditions on the fishery, the main fishing ground was concentrated on the area of $5^{\circ}N{\sim}10^{\circ}S$, $140^{\circ}E{\sim}180^{\circ}$ through the decades. When stronger El-nino occurred, the range of fishing ground tended to expand and main fishing ground moved to the eastern part of western and central Pacific Ocean. During this season, yellowfin tuna had high CPUE and catch proportion of yellowfin tuna in the eastern part also increased. As for the proportion of fishing effort by set type, proportion of log associated set was high during El-nino season while that of FAD associated set was high during La-nina season.

• 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.

• 한국수산과학회지
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• 제46권6호
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• pp.851-855
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• 2013

To determine the status of sunfish fishery, fishing places, body size, weight, etc. were investigated from 2010 to 2012 in Busan Cooperative Fish Market. Most of the sunfish were caught by large purse seine around Jeju island, and the fishing ground of sunfish were reached from Heuksando in the southern Yellow Sea to Guryongpo in the southern East Sea. The range of total length (TL) of the sunfish caught by purse seine was 55-271 cm, and the estimated length-weight relationship was $BW=8E-06TL^{3.3797}$. From the relationship, the weight of 50 cm in total length was estimated to be ca. 4 kg, TL 100 cm was ca 46 kg, TL 200 cm was ca 478 kg, and TL 271 cm was estimated to be 1,336 kg.

• 수산해양기술연구
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• 제49권3호
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• pp.282-290
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• 2013

The global warming related to GHG (greenhouse gases) emissions from industries is a major issue globally. Furthermore, GHG emissions from the fishery industries also represent an important issue, as indicated by "The Code of Conduct for Responsible Fisheries" at the Cancun, Mexico, meeting in 1992 and by the Kyoto protocol in 2005. Korea pronounced itself to be a voluntary exclusion management country at the 16th IPCC at Cancun, Mexico, in 2010. However, few analyses of GHG emissions from Korean fisheries have been performed. Therefore, a quantitative analysis of GHG emissions from the major Korean fisheries is needed before guidelines for reducing GHG emissions from the fishing industry can be established. The aim of this study was to assess the present GHG emissions from the Korean Purse seine fishery using the LCA (life cycle assessment) method. The system boundary and allocation method were defined for the LCA analysis. The fuel consumption factor of the purse seine fishery was also calculated. The GHG emissions for the edible fish were evaluated by determining the weights of whole fish and gutted fish. Finally, the GHG emissions required to produce 1kg of whole fish and 1kg of edible fish were deduced. The results will help determine the GHG emissions from the fishery. They will also be helpful to stakeholders and the government in understanding the circumstances involved in GHG emissions from the fishing industry.

• 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.

• 한국해양학회지:바다
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• 제6권3호
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• pp.164-179
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• 2001

1991년부터 1994년 사이에 한국 근해에서 대형선망에 어획된 수산생물의 종조성, 어획량, 분포의 계절 및 연 변동 양상을 파악하였다. 조사 기간 중 전체의 0.1%이상을 차지하는 주요 종은 19종이 출현하였으며, 그중 고등어(Scomber japonicus)가 전체 생체량의 54.7%, 정어리 (Sardinops melanostictus) 20.4%, 전갱이 (Trachurus japonicus) 9.1% 그리고 삼치(Scomberomorus niphonius) 6.2%로 이들 부어류 4종이 전체의 90% 이상을 차지하였다. 어획노력량은 봄부터 높아져 여름에 최고였고 가을철까지 높았으나, 단위노력당 어획량은 가을부터 높아져 겨울에 최고를 보였고 봄까지 높게 나타났다. 이는 산란과 섭이를 위해 남북 이동을 하여 여름동안 분산되었던 부어류가 겨울철에는 월동장으로 회유하여 위집됨으로써 어획률이 높았기 때문으로 판단된다.