• Proceedings of the Korean Society of Fisheries Technology Conference
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• 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.421-422
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• 2001

우리나라의 연근해어업은 다종자원을 여러 가지 어구로 동시에 어획하는 복잡한 형태를 가지고 있다. 이러한 어업에는 대표적으로 기선저인망어업, 안강망어업, 선망 어업, 유자망어업 등이 있으며, 특히 본 연구의 대상인 선망어업의 경우 고등어, 전갱이, 정어리 둥 10여종을 동시에 어획되는 다종어업의 한 형태로 취급할 수 있다. (중략)

• Ocean and Polar Research
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• 제40권4호
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• pp.213-222
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• 2018

We investigated seasonal variations in the abundance of the adults and the resting eggs of copepods to understand the role of copepod resting eggs for maintaining their population inhabiting the coastal area of Dadaepo, Korea. Adults and resting eggs of copepods were collected bi-monthly with a conical net (45 cm mouth diameter, $330{\mu}m$ mesh size) and van Veen grab ($0.1m^2$ area), respectively, from October 2016 to September 2017. The species of resting eggs were identified using mtCOI gene. The mean abundance of copepods was highest in October ($3686{\pm}1190inds{\cdot}m^{-3}$) and lowest in January ($176{\pm}60inds{\cdot}m^{-3}$) with the dominance of Paracalanus parvus s.l.. Among copepod producing resting eggs, Acartia omorii and Centropages abdominalis were dominant. The mean abundance of resting eggs was the highest in July ($9148{\pm}6787eggs{\cdot}m^{-2}$) and the lowest in October ($530{\pm}348eggs{\cdot}m^{-2}$). Most of the collected resting eggs were identified as A. omorii's. The mean abundances of A. omorii adults and resting eggs were highest in July, and both abundances fluctuated in a similar pattern except in September. In September, A. omorii adults were observed in a state of low abundance, while their resting eggs occurred in a state of high abundance. These results suggest that A. omorii maintain their population by producing a large quantity of resting eggs, particularly diapause eggs, before the seawater temperature rises. These eggs would hatch and be newly recruited to their population when the environmental condition becomes favorable.

• Resources Recycling
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• 제10권5호
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• pp.8-15
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• 2001

Aluminum dross should be recycled in consideration of characteristics of the dross and its reutilization after processing. In this study, aluminum dross generated in the domestic secondary aluminum industry was processed to use it as raw material for producing aluminum hydroxide. Sample dross was classified according to its size. The dross smaller than $850\mu$m was leached with sodium hydroxide solution to extract the remaining aluminum from the dross into the solution, and then aluminum hydroxide precipitate was recovered (rom the leach liquor. Purity of the obtained aluminum hydroxide was above 98% and size of the sample was in range of $\3~39mu$m. Recovery of aluminum hydroxide precipitate was highest on condition that A/C ratio of the solution was 0.5 and pulp density was 14~16% at the leaching step. From the result, it was suggested that this process could be applicable to recycling of aluminum dross.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제52권4호
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• pp.430-436
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• 2019

The diet of Glyptocephalus stelleri was studied using 475 specimens collected in the coastal waters of the East Sea of Korea. The specimens ranged from 6.8 to 43.4 cm in total length (TL). G. stelleri was a crustacean feeder that consumed mainly euphausiids [percent index of relative importance (%IRI)=63.7%]. Polychaetes were the second largest prey component. The diet also included small quantities of bivalves, copepods, amphipods and shrimps. Individuals smaller than 15 cm TL fed mainly on euphausiids. The proportion of euphausiids decreased as body size increased, whereas the consumption of polychaetes increased gradually.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• 제57권2호
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• pp.173-184
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• 2021

In this study, internationally widely utilized bioeconomic models were used to make a comparison and analyze the effectiveness of red snow crab fisheries management measures. As a specific effect analysis, biological and economic effects of both total allowable catch (TAC) and effort reduction management measures were analyzed simultaneously. Model results showed that the red snow crab biomass would be decreased from 106,000 tons to 73,076 tons after ten years when the TAC is set to and maintained at the current level of 26,000 tons. The amount of biomass would be increased to 125,316 tons when the level of TAC is set to 22,000 tons. In cases of reduced fishing efforts, a 30% decrease from the current level would result in greater biomass and NPV would be also estimated at the highest level. In addition, a sensitivity analysis by market price was conducted to analyze the minimum TAC level of the red snow crab offshore pot fishery. Results showed that the minimum TAC level would be 8,210 tons when the market price increased by 30% and it would be also 15,247 tons when the market price decreased by 30%. Furthermore, results of the sensitivity analysis by fishing cost showed that the minimum TAC level was analyzed to be 13,857 tons when the fishing cost increased by 30% from the current level.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제56권2호
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• pp.228-242
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• 2023

We examined the osteological development of the cranium, visceral skeleton, pectoral girdle, vertebral column, fins, and pterygiophore of small yellow croaker Larimichthys polyactis cultured at the Jeju Fisheries Research Institute. At 5.89 mm NL (notochord length), the larvae already had ossified frontal and basioccipital bones, parasphenoids, and vomer in the cranium. All elements of the visceral skeleton except the metapterygoid were ossified at 5.89 mm NL. Preorbital bone was ossified at 8.11 mm SL (standard length), and suborbital bones were ossified at 12.90 mm SL. In the vertebral column, ossification proceeded from the first to last centrum. The urostyle ossified at 7.41 mm SL. The caudal skeleton ossified at 6.78 mm NL, along with three hypural bones. In the pectoral girdle, the cleithrum, supracleithrum, postcleithrum, and post-temporal bones ossified at 5.89 mm NL. Caudal fin ossification began at 6.19 mm SL and was complete at 7.16 mm SL. Dorsal and anal fin ossification began at 7.16 mm SL and was complete at 8.62 mm and 8.11 mm SL, respectively. Anal and dorsal pterygiophore bone ossification was complete at 9.86 mm and 11.54 mm SL, respectively, and that of the supraneural bones was complete at 9.60 mm SL.

• Korean Journal of Ichthyology
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• 제35권4호
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• pp.372-377
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• 2023

This is the first report of Trachinotus blochii (Perciformes: Carangidae) from Korea. Single specimen (89.8 mm SL) was collected by seine fishing from the coastal waters of Busan on 13 September, 2023 and two specimens (29.53~30.78 mm SL) were collected by scoop net from Jejudo Island, Korea. This species is distinguishable from the most similar species, Trachinotus blochii as follows: it has the no black spots (vs. black spots in T. baillonii), 21~25 dorsal fin rays (vs. 18~20), and 20~24 anal fin rays (vs. 16~18). In order to confirm their taxonomic status, their mitochondrial DNA cytochrome c oxidase subunit I sequences were obtained and compared with those of carangid species recorded in the NCBI database. As a result, it was perfectly matched to T. blochii, and differed from T. baillonii (genetic distance=5.46%). We propose a Korean name, "Mu-jeom-mae-ga-ri", for the species.

• Korean Architects
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• 3호통권431호
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• pp.88-99
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• 2005

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 한국어업기술학회 2002년도 춘계 수산관련학회 공둥학술발표회
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• pp.416-417
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• 2002

• Journal of the Korean Professional Engineers Association
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• 제32권5호
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• pp.71-76
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• 1999