• 수산해양기술연구
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• 제41권2호
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• pp.95-100
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• 2005

In order to improve the gill nets for croaker, Miichthys miiuy which is proper to the fishermen's income ans fisheries resource management, we had studied to the net height of present gill nets (mesh size 160mm, 50 mesh in depth), experimental gill nets-I(mesh size 150mm, 68 mesh in depth) and experimental gill nets-II(mesh size 142mm, 75 mesh in depth) in wter using the gill nets design ans analysis simulation system, and then investigated and analyzed the catch efficiency of each gill nets through the field fishing experiments. The net height of emperimental gill nets-I and experimental gill nets-II in water were estimated respectively about 1.5 times and 1.3 times higher than present gill nets which the net height is about 3.5m as the results of simulation considering the current of fishing fields. Total number of croakers which were caught by the persent gill nets was 62(body length 300~1,200mm), total catch weight was 398.7kg (mean 0.6kg/sheet). Total number of croakers which were caught by the experimental gill nets- I was 68(body length 600~1,100mm), total catch weight was 391.6kg (mean 1.2kg/sheet). Total number of croakers which were caught by the experimental gill nets-II was 28(body length 400~900mm), total catch weight was 99.2kg (mean 0.3kg/sheet).

• Applied Microscopy
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• 제39권4호
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• pp.319-324
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• 2009

농어 아가미는 새파, 새궁, 새엽 및 새판으로 구성되어 있었다. 위쪽 새파수는 7~10개이며, 아래쪽 새파수는 13~18개로 조사되었다. 농어 아가미의 주요부위인 새엽과 새판(이차새엽)을 광학현미경과 투과전자현미경에서 관찰한 결과는 다음과 같다. 농어 아가미는 새궁(gill arch) 외연의 앞 뒤 2열로 된 긴 점막성의 빗살과 같은 모양으로 줄지어 있는 많은 수의 새엽(gill filament)을 가지고 있으며, 각 새엽은 전후 두개의 새판(gill lamellae)이 근접하여 두 열로 배열되어 있었다. 농어의 새판은 pavement cell, 기둥세포(pillar cell), 혈구세포, 점액세포(mucose cell) 및 염류세포(chloride cell) 등으로 구분되었다. 새판의 표면은 단층으로 큰 핵을 가진 pavement 세포로 구성되며, 상피표면의 glycocalyx로 덮혀진 미세융기를 가진다. 그리고 새판은 기둥세포와 혈구세포와 일정한 간격을 두고 분포하고 있었다. 점액세포는 새판에 드문드문 나타났지만 새엽에 많이 분포하고 있으며, 염류세포는 미토콘드리아와 tubular system이 잘 발달되어 있었다.

• 수산해양기술연구
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• 제43권1호
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• pp.28-37
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• 2007

In order to develop the biodegradable monofilament gill net for the protection of marine ecosystem and reduction of ghost fishing, enpol monofilament gill net was made for Chionoecetes opilio using polybutylene succinate as a biodegradable chip. Catching efficiency on 2 type monofilament gill net, PA and Enpol, were carried out using 2 commercial fishing boats around the fishing ground of Wang-dol rock from January 2004 to May 2006. Enpol monofilament gill net spun polybutylene succinate as a biodegradable chip was appeared high practicality for Chionoecetes opilio gill net. Target fishing ratio were 98% and 98.3% for the PA and enpol monfilament gill net, respectively. In addition, CPUE ratio of female and male(CL < 90mm) to Chionoecetes opilio caught in the enpol gill net were 25.3-40.3%, 14.0-22.1% less than PA gill net, respectively. However, CPUE ratio of male(CL > 90mm) to Chionoecetes opilio caught in the enpol gill net were 2.5-11.3% more than PA gill net. There was no difference in CPUE of female and male to Chionoecetes opilio caught using 2 gill nets as a result of the significance level of 5% by T-test.

• 한국수산과학회지
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• 제36권2호
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• pp.107-112
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• 2003

Effect of PCBs on the skin and gill development of olive flounder, Paralichthys olivaceus were investigated by histological methodology and morphometric data. The olive flounder were exposed to limit concentration of effulent of PCBs (3.0 ${\mu}g/L$) for 60 days. Skin development can be classified into four stages: SSEL (simple squamous epithelial layer), MCA (mucous cell appearance) & CCA (club cell appearance) DLA (dermal layer appearance), and SEL (startification of epidermal layer) stages. Gill development had five stages: GFA (gill filament appearance), IGFE (identification of early gill filament epithelial cell) MCA (mucous cell appearance), PCA (pillar cell appearance), and FGL (formation of gill lamella) stages. The periods of structural completion of skin and gill were 22-30 days and 23-30 days after hatching in the exposure group respectively. The process of development of skin and gill of the exposure group was very similar to that of the control group. Therefore, PCBs (3 ${\mu}g/L$) have no influence on the development of skin and gill in the larval stage of olive flounder.

• 수산해양기술연구
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• 제46권4호
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• pp.281-291
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• 2010

To estimate the mesh selectivity of monofilament and multifilament gill net for Marbled sole, Pleuronectes yokohamae, the field testes were carried out 12 times with five different mesh sizes (86.6, 101.0, 121.2, 137.7, 151.5mm) in the western sea of Korea, 2007-2009. The master curve of selectivity was estimated by the extended Kitahara's method. In the field testes, the total number of species and catch were 26 and 987, respectively. The catch number of marbled sole was 728 and occupied 73.8% in total catch. The optimum values of l/m for 1.0 of retention probability in monofilament and multifilament gill net were estimated 0.288 and 0.307, respectively and l/m was estimated to be 0.189, 0.203, 0.213, 0.222 and 0.230 in case of monofilament gill net and 0.171, 0.191, 0.205, 0.216 and 0.227 in case of multifilament gill net when the retention probability were 0.1, 0.2, 0.3, 0.4 and 0.5, respectively. The 0.5 selection range of multifilament gill net was wider about 1.5 times than that of monofilament gill net according as multifilament gill net was 0.216 and monofilament gill net was 0.148. So the multifilament gill net has a low selectivity than that of the monofilament gill net. To estimate the optimum mesh size on first maturity length 19.5cm of marbled sole, the retention probability value of 0.1 was adopted in consideration of using the gill net for marbled sole at present. The optimum mesh size were estimated to be 103.2mm and 114.0mm in monofilament gill net and multifilament gill net, respectively, on first maturity length 19.5cm of marbled sole.

• Fisheries and Aquatic Sciences
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• 제5권1호
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• pp.75-78
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• 2002

The effects of Coehlodinium polykrikoides on the gill of red sea bream, Pagrus major, were examined to clarify the ichthyotoxic mechanisms of this plankton species. The gill of fish exposed to dense blooms over 3,000 cells/mL for 24 h showed severe epithelial separation: a severe edema was found in the secondary lamellar epithelium and interlamellar regions of primary filament. In addition, lipid peroxidation of gill tissue in Coehlodinium-exposed fish was about 2.5 times higher than that of control. The composition of glycoproteins in the gill mucus of Coehlodinium-exposed fish was also changed. These results suggest that the loss of structural integrity of cell membranes in fish gill may be deeply involved in fish death by C. polykrikoides.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2005년도 2005 Annual Meeting & International Symposium
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• pp.129-130
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• 2005

• 한국환경보건학회지
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• 제29권2호
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• pp.77-79
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• 2003

뉴포트 어시장에서 채집한 볼락류인 Sebastes crameri로부터 17개체의 아가미 기생물을 발견하였다. 그중 9개체는 단생흡충류인 Trochopus australis이고 나머지 8개체는 요각류인 Neobrachiella robusta였다. 이 기생물의 가장 많이 발견되는 부위는 볼락류의 제 2 아가미새궁과 배측 후부였다. 단생류인 T. australis는 주로 제 2 아가미 새궁에서 요각류인 N. robusta는 제 1 아가미새궁에서 발견되었으나 요각류는 제 4 아가미새궁에서는 발견되지 않았다. 이번 연구에서 기생물의 아가미 부착은 주로 제 1, 2 새궁의 배후측에, 그러나 제 3, 4 아가미새궁의 전복측과 중앙에는 적게 분포되어 있었다.

• 수산해양기술연구
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• 제49권2호
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• pp.95-105
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• 2013

Physical characteristics of net filament were investigated to test the fishing capacity of gill nets due to the flexibility difference between nylon and biodegradable nets (PBS 95%+PBAT 5% and PBS 80%+PBAT 20%). In addition, a total of 16 fishing experiments were conducted in the coastal waters of Jeongja, Ulsan, from August 10 to October 20, 2011 and from September 11 to November 3, 2012. The test results showed that nylon net filament exhibited more flexibility than biodegradable net filament when they were wet. Accordingly, the longer submerged time, the more fishing capacity the nylon gill nets demonstrated in comparison with the biodegradable gill nets. A total of 16 species were caught in 2011 with the nylon gill nets (1,323 fishes, weighing 342,885g) and the biodegradable gill nets (958 fishes, weighing 236,857g). 15 species were caught in 2012 with the nylon gill nets (1,582 fishes, weighing 448,360g) and the biodegradable gill nets (1,431 fishes, weighing 406,590g). Thus catch weights and the number of fish caught produced by the nylon nets were 1.45 times and 1.38 times higher than those of the biodegradable nets produced in 2011, and 1.1 times and 1.11 times higher in 2012. A test on the target species, pointhead flounder (Cleisthenes pinetorum) has similar results. The flexibility of a net was proved to be related to the fishing capacity, and as a result, it is concluded that the higher flexibility, the higher fishing capacity.

• 수산해양기술연구
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• 제40권3호
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• pp.182-188
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• 2004

홑자망과 삼중자망에 의한 어획성능을 파악하기 위하여 한국 남해안의 거문도연안에 시설된 세라믹 어초어장에서 어구 성능시험과 수중 비디오 카메라로 어군 위집상을 조사로 하였다. 흩자망에 의한 폭당 어획량은 삼중자망에 비해 49.2% 많았으나, 어종수는 34.5% 적었는데, 이를 ANOVA로 분석한 결과 5% 유의수준에서 차이가 없었다. 어구별 우점종은 홑자망에서 참돔 1종, 삼중자망에서 참돔, 말쥐치, 홍어 등 3종이었으며, 홑자망에의해 어획된 참돔의 체장범위와 평균체장은 삼중자망에 어획된 참돔보다 다소 적게 나타났다. 홑자망에 의한 어획성능이 삼중자망보다 높았던 원인은 홑자망에 어획되기 쉬운 어종이 군을 형성하고 있었고, 개체의 크기도 홑자망에 적합하였기 때문이라고 판단된다.