• Proceedings of the Korean Aquaculture Society Conference
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• 2006.05a
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• pp.308-309
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• 2006

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.11a
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• pp.529-530
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• 2018

• 한국해양학회지
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• v.27 no.4
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• pp.290-302
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• 1992

Seasonal variations of salinity in the upper 500 m of the tropical Atlantic Ocean are examined, based on both climatological seasonal salinity observations and numerical simulations with hydrological forcing. The seasonal cycle of sea surface salinity has strong seasonal variations caused by shifts of the freshwater surplus zone (i.e. the intertropical convergence zone) and the river outflow. The climatological seasonal salinity in this analysis concurs with other independent observations described by Default (1981) and Levitus (1982), but provides more consistent patterns with temperature structure. The effect of salinity on density below 100 m depth in the tropical Atlantic is negligible compared to tat of temperature, which in the mixed layer salinity affects density significantly. The systematic difference between observed and simulated salinity is found to be the fact that the simulated salinity is higher in the subtropics than the observed salinity, and possible sources about the difference are also discussed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.6
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• pp.934-941
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• 2020

The spatial and temporal catch variations of Argentine shortfin squid Illex argentinus in the Southwest Atlantic Ocean (SWA) were analyzed using Korean squid-jigging fishery data collected through electronic reporting system (ERS) from 2016 to 2020. The ERS linked with GPS has been implemented for collecting fishing data from all Korean fishing vessels operating in international waters since November 2015. The fishing period of the Korean squid-jigging fishery in the SWA runs from early summer to autumn (December to June) in the Southern Hemisphere. The fishing ground was extended from 42°S to 48°S along the Patagonian continental shelf and slope, and the main fishing ground was formed around the Falkland Islands. The yearly catch per unit effort (CPUE) of I. argentinus fluctuated between 1.69 and 7.53 tons/day. In this study, during the fishing season, a south and westward shift on the fishing ground was observed indicating the feeding migration of the south Patagonian stock. The shift in monthly fishing centroids differed according to fishing season. The gradual southward shifts of fishing centroids were observed in the catch years (2017 and 2018), whereas unapparent shifts in fishing centroids were observed in the low catch years (2016 and 2019).

• International Journal of Naval Architecture and Ocean Engineering
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• v.8 no.1
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• pp.73-82
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• 2016

In order to extend the operational life of Underwater Moored Platforms (UMPs), a horizontal axis water turbine is designed to supply energy for the UMPs. The turbine, equipped with controllable blades, can be opened to generate power and charge the UMPs in moored state. Three-dimensional Computational Fluid Dynamics (CFD) simulations are performed to study the characteristics of power, thrust and the wake of the turbine. Particularly, the effect of the installation position of the turbine is considered. Simulations are based on the Reynolds Averaged Navier-Stokes (RANS) equations and the shear stress transport ${\kappa}-{\omega}$ turbulent model is utilized. The numerical method is validated using existing experimental data. The simulation results show that this turbine has a maximum power coefficient of 0.327 when the turbine is installed near the tail of the UMP. The flow structure near the blade and in the wake are also discussed.

• Development and Reproduction
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• v.18 no.3
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• pp.167-172
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• 2014

In the present study, muscle tissues were obtained separately from individuals from Atlantic hairtail population (AHP), Gunsan hairtail population (GHP) and Chinese hairtail population (CHP), respectively. The seven decamer primers were used to generate the shared loci, specific, unique shared loci to each population and shared loci by the three hairtail populations. Here, averagely, a decamer primer generated 64.7 amplified products per primer in the AHP population, 55.7 in GHP population and 56.4 in CHP population. The number of unique shared loci to each population and number of shared loci by the three populations generated by genetic analysis using 7 decamer primers in AHP, GHP and CHP population. 119 unique shared loci to each population, with an average of 17 per primer, were observed in the AHP population, and 28 loci, with an average of 4 per primer, were observed in the CHP population. The hierarchical dendrogram point out three main branches: cluster 1 (ATLANTIC 01 ~ ATLANTIC 07), cluster 2 (GUNSAN 08 ~ GUNSAN 14) and cluster 3 (CHINESE 15 ~ CHINESE 21). The shortest genetic distance displaying significant molecular difference was between individuals' CHINESE no. 16 and CHINESE no. 18 (0.045). In the long run, individual no. 01 of the AHP population was most distantly related to CHINESE no. 19 (genetic distance = 0.430). Consequently, PCR analysis generated on the genetic data displayed that the geographic AHP population was widely separated from CHP population, while individuals of CHP population were fairly closely related to those of GHP population.

• Journal of the Korean earth science society
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• v.44 no.2
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• pp.135-147
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• 2023

Satellite-observed significant wave heights (SWHs), which are widely used to understand the response of the ocean to climate change, require long-term and continuous validation. This study examines the accuracy and error characteristics of SWH observed by nine satellite altimeters in the North Pacific and North Atlantic Ocean for 25 years (1992-2016). A total of 137,929 matchups were generated to compare altimeter-observed SWH and in-situ measurements. The altimeter SWH showed a bias of 0.03 m and a root mean square error (RMSE) of 0.27 m, indicating relatively high accuracy in the North Pacific and North Atlantic Ocean. However, the spatial distribution of altimeter SWH errors showed notable differences. To better understand the error characteristics of altimeter-observed SWH, errors were analyzed with respect to in-situ SWH, time, latitude, and distance from the coast. Overestimation of SWH was observed in most satellite altimeters when in-situ SWH was low, while underestimation was observed when in-situ SWH was high. The errors of altimeter-observed SWH varied seasonally, with an increase during winter and a decrease during summer, and the variability of errors increased at higher latitudes. The RMSEs showed high accuracy of less than 0.3 m in the open ocean more than 100 km from the coast, while errors significantly increased to more than 0.5 m in coastal regions less than 15 km. These findings underscore the need for caution when analyzing the spatio-temporal variability of SWH in the global and regional oceans using satellite altimeter data.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.13 no.2
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• pp.27-32
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• 1977

The paper deals the fishing condition of the stern trawlers operated in the Atlantic coast of Africa. The datas are gathered from the Korean stern trawlers operated in the area from June, 1975 to May, 1976. The obtained results are summarized as follows: 1. The mean catch per haul are calculated as, cuttle fish 14.5kg, large size squid(more than :lOOg of body weight) 28.2kg, small size squid(less than 300g) 36.4kg, octopus 47.0kg. 2. Small size cuttle fish(less than5OOg of body weight) are caught much during after spring tide in July to September, yet, large size ClIttle fish(more than 500g) are caught much during neap tide in October to January. 3. Small size squid(less than 300g of body weight) are cBught much during after spring tide in October to December, yet, large size squid(more than 3OOg) are caught much during before spring tide in October to March. 4. Octopus are caught during neap tide in July to August.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.42 no.4
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• pp.203-209
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• 2006

This paper described the experimental squid jigging fishery conducted by a commercial fishing vessel in the Northwest Atlantic Ocean from August to October 2005. Author carried out experimental jiggings of 65 times during 57 days by three type of jigs which were pick jig, soft jig and soft luminous jig. The total catch, effort/day and catches/line-day of northern shortfin squid (Illex illecebrosus) were 12,726kg, 35 auto jigging machine and 3.5kg, respectively. Higher CUPE was observed in September, August and October. Catch ratio of pick jig was higher by 57-86% than those of soft jig and soft luminous jig. Higher catch was recorded at the $42^{\circ}55'N,\;62^{\circ}10'W$ with surface temperature ranging $18-21^{\circ}C$. The range of the dorsal mantle length was from 13.5cm to 23.0cm with average 17.2cm for female and from 13.0cm to 20.0cm with average 17.0cm for male. Sex ratio showed 55.4% of female.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.4
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• pp.282-294
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• 2004

Catches of Argentine shortfin squid Illex argentinus showed a sharp decrease, reaching 99,000ton in 1993 and 56,700ton in 1994, and then increased again reaching 130,300ton in 1997 from 78,600 ton in 1996. The Korean squid jigging fishery around Falkland for Illex argentinus commences usually its operation in January and lasts August and peak in catch was showed from March to May. To elucidate possible environmental effects on their abundance during the main fishing season in 1993-1994 and 1996-1997, sea surface temperatures were used as an indicator of the position and strength of the oceanographic structures in the Southwestern Atlantic Ocean. The high catch and catch per unit effort of Illex argentinus was showed when the Faliland Current was not affected in the fishing area in 1993 and 1997. But they were sharply decreased from the middle of April 1994 and the late of April 1996 when the Faliland Current directly affects the fishing ground.