• 수산해양기술연구
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• 제49권3호
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• pp.250-260
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• 2013

The annual and monthly fluctuation in the species composition and the catch abundance of dominant species were analyzed using the daily sales slip catch data by a set net in the offshore waters off Dolsan Island in Yeosu from March 2004 to December 2011. Mean catch from 2004 to 2011 is 372M/T and the maximum and the minimum catch are 526 M/T in 2005 and 27 2M/T in 2009, respectively. The dominant species were Engraulis japonicus mainly in spring and Scomberomorous niphonius in Autumn and therefore the set net catch that is dominated by S. niphonius's catch was much higher in autumn than in spring. Through comparative analyses for the environmental factors to the annual catch fluctuation, it is revealed that the water temperature variation affected the recruitment property of S. niphonius to the fishing ground but the effect of typhoon on the catch fluctuation was not distinct. Furthermore, the big blooming event of jellyfish, particularly Nemopilema nomurai, that occurred in 2009 showed a tendency of faster appearance and later extinction until December. The occurring characteristic of N. nomurai became a direct cause that brought about the lowest total catch in 2009 since the dominant species catch of the set net fishery was concentrated mostly in Autumn.

• 한국수산과학회지
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• 제47권6호
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• pp.997-1005
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• 2014

We analyzed annual and seasonal variations in fish species composition and distribution patterns using both daily catch and quantitative analysis data collected from a set-net fishery over a period of two years (2011-2012) on the coast of Dapo, Geoje Island. Set-net fishing season in this area is from May to November, and the annual yield based on the daily catch data was 171,412 kg in 2011, and 102,611 kg in 2012. In total, there were 46 species (belonging to 36 families and 12 orders) in 2011, and 41 species (belonging to 25 families and 9 orders) in 2012. The dominant species in terms of numbers were Trachurus japonicus, Engraulis japonicus, Clupea pallasii, Scomber japonicus, and Sphyraena pinguis. The range in fork length for T. japonicus and E. japonicus was from 3.2 to 23.9 cm, and from 2.6 to 13.3 cm, respectively. The fork length of recruiting juveniles to the Dapo set-net fishing ground ranged from 4.6 to 7.8 cm (median) for T. japonicus, and from 4.1 to 5.0 cm (median) for E. japonicus. The fact that most of the fish caught from the two species were at immature growth stages implies that the coast of Dapo can act as a nursery area for these migratory species.

• 수산해양기술연구
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• 제29권2호
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• pp.94-108
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• 1993

In order to investigate the relation between the environmental properties and catch fluctuation of set net fishing ground located in the coastal waters of Yeosu, oceanographic observation and catches on the grounds were carried out from Jan. to Dec. in 1990 and 1992. The results obtained are summarized as follows; 1) Because of the surveyed area is a costal shallow water, the fishing ground was influenced largely by atmospheric phenomena such as air temperature. precipitation. etc. and so showed large variations in temperature and salinity yearly. The inner water flowed out mainly between Yeosu ad Namhe-do, and then through Kumo-do between Dolsan-do and Kumo-do. On the other hand, off shore water was supplied into the fishing ground from the vicinity of Sori-do and Yokchi-do. thus the fishing ground was occupied usually by various sources of water. 2) The water mass in the fishing ground were divided into the inner water(29.0～30.6$\textperthousand$) and the mixed water(31,7～32.2$\textperthousand$) and off shore water(32.3～32.8$\textperthousand$) accourding to the distribution of salinity from T-S diagram plotted all salinity data observed in 1990 and 1992. In summer the inner and mixing water which was formed by river flowed southerly and spread south-easterly in the vicinity of Kumo-do. The off shore water which supplied from the vicinity of Sori-do and Yokchi-do and inner water formed the thermal front and halo front in summer. 3) The fishes caught by the set net were arranged in the order of catch amounts as follows: Spanish mackerel>Horse mackerel >Hair tail>Common mackerel> Sardine> Anchovy. The Catches of anchovy and sardine were high in April to May and those of hair tail and horse mackerel in July to September, but spanish mackerel were caught during the whole period of fishing. When inner water and mixing water appeared respectively and inner water and mixing water speared together in the set net fishing ground, the set net showed a high catch.

• 수산해양기술연구
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• 제32권3호
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• pp.217-222
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• 1996

대형정치망의 원통내에 있어서 멸치어군의 이동행동은 1992년 12월 1일부터 12월 4일까지 일본국 석천현 칠미시 연안에 있는 안단 정치망 어장 3호망에서 스케닝 소나를 이용하여 실시하였는데, 그 결과를 요약하면 다음과 같다. 1. 2개의 원통시아에 어군의 이동행동은 주야간에 차이가 있었고, 밤보다는 낮에 더 많이 이동하였다. 2. 제2 원통에 멸치어군이 존재하였을 때, 제1원통에 있는 멸치어군이 제2 원통으로의 입망 비율은 78%였고, 제2 원통에 멸치어군의 존재는 제2원통에의 입망 비율에 영향을 미쳤다는 것을 시사하고 있다. 그러나, 제2원통에 조밀하게 멸치어군이 존재하였을 때, 제 2원통에 입망한 어군의 체류시간은 매우 짧았고, 제2 원통에서 어군의 밀도 상승은 어군의 도피 비율을 증가시킨다는 것을 시사하고 있다. 3. 멸치어군은 원통에 입망할 때, 대부분이 망의 중앙에서 먼바다 쪽으로 방향을 바꾸어 이동하였다.

• 한국어류학회지
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• 제17권4호
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• pp.279-286
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• 2005

2004년 5월부터 2005년 1월까지 강원도 고성군 죽왕면 오호리 연안에서 자망과 정치망으로 사계절에 걸쳐 출현하는 어류의 종조성 및 계절변동을 조사하였다. 동해 중부연안에서 자망과 정치망에서 어획된 어류는 총 11목 31과 59종으로, 자망에서 6목 15과 33종, 정치망에서 10목 26과 36종이 출현하였다. 자망에서는 쏨뱅이목 (Scorpaeniformes)이 우점하였으며, 어종수 및 개체수에서는 여름철이 다른 계절에 비해 높았고 생체량은 겨울철이 가장 높았다. 반면 정치망의 경우 농어목 (Perciformes)이 우점하였으며, 어종수는 가을철, 개체수는 봄철, 생체량은 겨울철에 각각 높았다. 동해 중부해역은 동해 남부해역과 달리 쏨뱅이목 및 가자미목 어류가 상대적으로 우점하게 출현하였다. 각 네트에 대한 주성분분석 결과는 동지역, 동시기에 조사가 이루어졌다 할지라도 사용 어구에 따라 종조성이 달라지는 것을 보여주었다.

• 수산해양기술연구
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• 제22권3호
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• pp.1-7
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• 1986

This is a basic study of further investigating the effect of oceanographic conditons, such as bottom profile, currents, and temperature, to the fish migrating course around the set-net. The survey was held at Dojang Po, southern part of Geoje Island, from July to October in 1985. There was a sea valley of which depth was 20 to 40 meters around the set-net. Near the bottom of that sea valley, there was different current pattern to the upper layer. In the sea calm condition of July and October, the vertical profiles of current and water temperature were simple. But in rough condition of September, they were complicated because of wind tuburance.

• 정보처리학회논문지B
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• 제9B권6호
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• pp.783-790
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• 2002

본 논문에서는 구간값 퍼지집합 추론의 퍼지 Pr/T 네트 표현을 제안한다. 여기에서 퍼지생성규칙은 지식표현을 위해 사용하고, 퍼지생성규칙의 믿음값은 구간값 퍼지집합으로 표현한다. 제안한 구간값 퍼지집합 추론 알고리즘은 퍼지생성규칙의 전제부와 결론부에 있는 퍼지개념에 따라서 적절한 믿음값평가함수를 사용하기 때문에 다른 방법보다 사람이 사용하는 직관과 추론에 더 가깝다.

• Near Infrared Analysis
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• 제1권2호
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• pp.1-8
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• 2000

Using the net analyte signal, hybrid linear analysis was proposed to predict chemical concentration. In this paper, we select a sample from training set and apply orthogonal signal correction to obtain an improved pseudo unit spectrum for hybrid least analysis. using the mean spectrum of a calibration training set, we first show the calibration by hybrid least analysis is effective to the prediction of not only chemical concentrations but also physical property variables. Then, a pseudo unit spectrum from a training set is also tested with and without orthogonal signal correction. We use two data sets, one including five chemical concentrations and the other including ten physical property variables, to compare the performance of partial least squares and modified hybrid least analysis calibration methods. The results show that the hybrid least analysis with a selected training spectrum instead of well-measured pure spectrum still gives good performances, which is a little better than partial least squares.

• Fisheries and Aquatic Sciences
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• 제24권1호
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• pp.41-52
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• 2021

Data for fish species composition and the catch of fish species were obtained from the daily trading records for the period between April and December 2016 to 2018 at the set net fishing grounds in Yeosu Bay, Korea. The annual mean total catch was 195.8 tons, and the dominant species was the Spanish mackerel (Scomberomorus niphonius), which accounts for about 55 percent of the total catch. The catch increased in spring and autumn. Increase in spring is caused by not Spanish mackerel but other fish while the increase in autumn by Spanish mackerel. The distinct increase of the catch in summer, 2017 was due to the new recruitment of small-sized Spanish mackerel, which was probably to be from the fish population hatched in spring in the East China Sea. Our results showed a strong correlation between water temperature and catch fluctuation. The catch increases with the increase in water temperatures, and the periodic pattern of the water temperature and catch fluctuation is more consistent in the offshore waters, in which warm current flows, than in the coast waters.

• 수산해양기술연구
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• 제37권1호
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• pp.24-34
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• 2001

정치망 원통의 거동을 장기선 방식으로 측정할 수 있는 계류식 수중위치측정시스템을 제작하고, 그 실용성을 확인하기 위하여 소조기 (2000. 10. 6)와 대조기 (2000. 11. 28)에 현장실험을 실시하였다. 현장실험에서 4개의 트랜스폰더는 원통의 남북방향으로 부착시키고, 1개의 트랜스폰더는 해저에 고정시켰다. 그리고, 원통까래의 상하진동은 3개의 테이터로거를 원통의 동서방향 (원통의 길이 방향)으로 부착시켜 대조기에 관측하였다. 소조기에 측정한 원통의 동서방향, 남북방향, 상하방향의 변화폭은 각각 3.2 m, 3.4 m, 2.1 m이었고, 대조기에는 각각 7.8 m, 7.8 m, 5.0 m로 소조기보다 2.3배 이상 컸다. 원통까래의 상하진동폭은 비탈그물에 가까운 쪽이 3.2 m, 중앙부가 3.7 m, 머거리쪽이 8.4 m이었다. 전반적으로 유속이 10 cm/s 이상일 때와 흐름의 방향이 원통의 길이방향과 일치하지 않을 때에 까래의 심도 감소와 상하진동이 빈번하게 발생하였다. 해저에 고정시킨 트랜스폰더를 사용하여 수파기 좌표의 변동을 측정한 결과, 정치망 사개에 부착한 수파기라도 흐름에 의해 그 좌표가 수 m 정도 변함을 알 수 있었고, 정치망의 거동 측정시 이러한 좌표의 변동을 보정하여야 측정오차를 줄일 수 있음을 알 수 있었다. 본 연구에서 제작한 3차원 수중위치측정시스템의 위치오차는 가두리에서 측정한 결과, x축, y축, z축이 각각 0.6 m, 0.8 m, 1.2 m이었고, 기선의 내부이거나 기선에 가까울수록 작았다.