• 한국수산과학회지
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• 제17권1호
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• pp.47-54
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• 1984

태평양 서부 적도해역에서 조업하는 다랑어 선망어선 4척으로 부터 다랑어 어군 370개의 어군속성, 어군에 대한 선망조업의 경과, 어획물등에 관한 자료를 얻어 이것을 통계학적으로 해석하여 다음의 결과를 얻었다. 1. 이 해역에서 발견되는 다랑어 표층역어군은 보편적으로 해오, 소형어류 및 부류물체와 함께 발견되었다. 2. 부류물체에 모인 어군에 대한 선망조업에서는 일출전시각에 투망되는 회수가 많고, 해조가 따르는 어군에 대한 조업에서는 일출후시각에 투망되는 회수가 많다. 3. 부류물체에 모인 어군에 대한 선망조업에서는 조업당어획량이 중위치이상인, 성공적조업의 회수가 많다. 4. 부류물체에 모인 어군에 대한 선망조업에서는한 어군에 대하여 한 번 투망한 다음 추가하여 제2차 이상 투망하는 수가 있다. 5. 부류물체에 모인 다랑어 어군의 크기는 물체의 길이와는 상관관계가 낮고, 물체의 구조와는 상관관계가 높다. 즉 통나무, 나무 판자등 단순한 구조의 물체보다는 뿌리나 가지가 달린 나무 줄기, 대나무 덤불 등이 뿌리 뽑힌 것과 같이 복잡한 구조의 물체의 어군유인효과가 크다.

• 자원ㆍ환경경제연구
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• 제15권1호
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• pp.71-94
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• 2006

최근 국제적으로 수산부문에 대한 현안문제 중의 하나는 어업에 있어 어획능력 (fishing capacity)을 감축시키고자 하는 것이다. 이는 어획능력이 크게 증강되어 어업자원에 대한 어획압력이 증가하여 자원남획을 초래하고 있을 뿐만 아니라 추가적인 비용이 소모되므로 지속 가능하고 경영안정적인 어업발전을 위해서는 과잉된 어획능력의 감축이 시급하기 때문이다. 더욱이 1999년에는 세계식량농업기구(FAO)가 '어획능력 관리를 위한 국제적 행동계획'을 채택하고, 각국으로 하여금 어업별 어획능력 측정과 과잉 어획 능력 감축을 위한 관리방안 마련을 촉구하였다. 본 연구에서는 1978년~2003년간의 어획량과 어획노력량(어선척수, 톤수, 마력수, 그리고 조업일수) 자료를 이용한 자료포락분석(DEA) 기법으로 우리나라 대형선망어업의 연도별 어획능력 변화를 측정해 보았다. 분석 결과, 2003년도의 경우 대형선망어업의 어획능력 활용도가 약 50% 수준으로 나타나 유휴 어획능력이 존재하는 것으로 평가되었다. 그리고 과잉 어획능력 감축 수준을 파악하기 위한 민감도 분석 결과 2003년도 어획량을 유지하기 위해서는 어선척수(마력수와 톤수 포함)를 50% 정도 삭감하든가 아님 조업일수를 약 63% 정도 줄여야 하는 것으로 나타났다. 또한 대형선망어업의 최대 지속적 어획량(MSY) 수준을 유지하기 위해서는 어선척수(톤수와 마력수 포함)에 대한 30% 삭감이나 조업일수의 약 60% 감소가 필요한 것으로 분석되었다.

• 한국수산과학회지
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• 제49권3호
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• pp.376-384
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• 2016

Seasonal catch distributions of large purse seines and daily landings of coastal set nets were analyzed to understand the migration path of the Spanish mackerel Scomberomorus niphonius around Korean waters. The Spanish mackerel start to move toward the coastal region in the South and West Sea in May for spawning and stay until July, when spawning finishes. Afterwards, they start to migrate to the East China Sea and the southern East Sea and are found irrespective of the onshore and offshore regions. Therefore, they disappear from the offshore region during the spawning season in June and July, and a new recruitment population of age 0 begins to inflow into the coastal fishing grounds in the South Sea and West Sea in August, one month earlier than in the Japanese coastal region of the East Sea.

• 수산해양기술연구
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• 제49권4호
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• pp.469-482
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• 2013

This study identified problems of the existing ecosystem-based fisheries assessment approach, and suggested new methods for scoring risk and for the estimation of fishery risk index. First, risk scores of zero to two for target and limit reference points for each indicator were replaced by those of zero to three, and the risk scores were calculated from new formulae which were developed in this study. Second, a new method for estimating fishery risk index (FRI) was developed in this study, considering the level of indicators. New method was applied to the Korean large purse seine fishery, large pair trawl fishery and drag net fishery. More precise and detailed risk scores were obtained from the new method, which can explain the risks by the wider range of both risk levels for 'better than target' and 'beyond limit'. The new method for estimating FRI could avoid the basic problem related with duplicated computations of fishery-level indicators, which improved the estimated FRI to be more accurate. Also, a method for estimating variance of FRI using the bootstrap was proposed in this study.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2002년도 추계 수산관련학회 공동학술대회발표요지집
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• pp.270-272
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• 2002

Competitive species have the same spatial distribution (habitat) and foraging behavior (niche), while non-competitive species have either different feeding behavior or spatial distribution. Therefore, ecological segregation among species of fish results rfom differences in foraging behavior and spatial distribution (Allen, 1984; Zhang 1988). To explore these ecological strategies among major small fish pelagics in Korean waters, distribution of CPUE in the Korean large purse seine fishery were examined. (omitted)

• 수산경영론집
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• 제44권1호
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• pp.71-79
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• 2013

This study is aimed to estimate market integration of wild caught fish species on the Korean market, using both multivariate and bivariate cointegration analysis. For the analysis of market integration between wild caught fish species, major four fish species those are most popular fish in the market and caught by the large purse seine fishery-chub mackerel, jack mackerel, hairtail and spanish mackerel-were selected as analytical target fish species. And their real monthly price data from January 2000 to December 2011 were used in the analysis. The results of the multivariate cointegration test for four wild caught fish species showed that there would be long-term equilibrium relationships among prices of four wild caught fish species, and consequently, the markets for wild caught fish species were estimated to be integrated. The results of exclusion test and bivariate cointegration test also supported that there would be a clear evidence to suggest that all target wild caught fish species were cointegrated each other.

• 수산경영론집
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• 제45권1호
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• pp.109-119
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• 2014

This study aimed to examine the applicability of a portfolio approach to the ecosystem-based fisheries management targeting the large purse seine fishery. Most fisheries are targeting multispecies and species are biologically and technically interacted each other. It enables a portfolio approach to be applied to find optimal production of each species through expected returns and risk analyses. Under specific assumptions on the harvest quota by species, efficient risk-return frontiers were generated and they showed a combination of optimal production level. Comparisons between portfolio and actual production provided a useful information for targeting strategy and management. Results also showed the possibility of effective multispecies fisheries management by imposing constraints on each species such as total allowable catch quotas.

• 수산경영론집
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• 제43권3호
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• pp.59-73
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• 2012

This study has the purpose to examine the effects of hygiene factor(job environment factor) and motivation factor(job motivation factor) of seamen on satisfaction, turnover intention and organizational commitment. To that end, with the scope of study subjects limited to coastal waters seamen, positive analysis was done through literature study and questionnaire analysis, and focus was given to the prospect of acquiring seamen by change of outside environment. Results of analyzing the factors affecting coastal waters seamen satisfaction, turnover intention and organizational commitment were as follows. First, the factors that affect satisfaction significantly are personal relationship and willingness to participate. Second, the factor that affects turnover intention significantly is employment stability. Third, the factors that affect organizational commitment significantly are personal relationship and willingness to participate.

• 한국수산과학회지
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• 제53권6호
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• pp.942-953
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• 2020

Achieving optimal sustainable yields (i.e., avoiding overfishing and maximizing fishery harvest at the same time) is one of the main objectives in fisheries management. Generally, management reference points (MRPs) such as fishing mortalities (Fmsy, F0.1, Fx%) have been suggested for the purpose. In this study, we intended to suggest MRPs for Korea chub mackerel Scomber japonicus stock, using a stochastic catch-at-age model (SCAA) and evaluate whether the current fishing intensity on the stock is appropriate. We used length frequency and catch-per-unit-effort data on the Korea chub mackerel stock collected from the large purse-seine fishery, and yields landed by all fisheries from years 2000 - 2019. We calculated yield per recruit and spawning potential ratio, and projected spawning stock biomass (SSB) under different fishing mortality, assuming annual recruitments were solely controlled by environmental effects (i.e., steepness of 1.0). Some of our major findings and suggestions were that the overfishing threshold would be F46%; i.e., the fishing mortality in the terminal year, 2019 was 0.257/year, which corresponded to F46%.

• 한국수산과학회지
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• 제54권5호
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• pp.769-781
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• 2021

Given data about the annual fishery yield of the common squid Todarodes pacificus, and the catch-per-unit-effort (CPUE) data from multiple fisheries from 2000-2018, we applied a Bayesian state - space assessment model for the squid population. One of our objectives was to do a stock assessment, simultaneously incorporating CPUE data from the following three fisheries, (i) large trawl, (ii) jigger, and (iii) large purse seine, which comprised on average a year about 65% of all fisheries, allowing possible correlations to be reflected. Other objectives were to consider both observation and process errors and to apply objective priors of parameters. The estimated annual exploitable biomass was in the range of 3.50×10⁵ to 1.22×10⁶ MT, the estimated intrinsic growth rate was 1.02, and the estimated carrying capacity was 1,151,259 MT. Comparison with available results from stock assessment of independently analyzed single fisheries revealed a large difference from the estimated values, suggesting that stock assessment based on multiple fisheries should be performed.