• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.3
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• pp.187-203
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• 2009

This study monitored marine environments in system coastal waters of the South Sea of Korea during the period of 2005-2007 and analyzed the data from environmental parameters and nutrients, which contributed to fluctuate marine environmental characteristics in aquaculture. On the basis of the fluctuation of temperature depending on seasons and sampling sites, too seasons of winter and summer showed a remarkable temperature gap of $5^{\circ}C$ compared with spring and autumn. Salinity in spring and summer approached 9 psu in Morkpo. Most of sampling sites showed COD below 2mg/L, indicating somewhat optimal environmental conditions. T-N and T-P also had desirable horizontal distributions all year round the concentration of SS was higher, but Chi. a was well-distributed horizontally except for Morkpo. Marone environmental parameters of surface water were similar to those of bottome water except for Morkpo. Most of sampling sites showed the ratio of N/P below 16, impling that nitrogen played an important role in growth of phytoplankton as a limiting factor. The relationship between Chi. a and nutrients was positive linear, whereas the relationship between Chi. a and COD were very strong positive. winder, Spring and Summer showed the strong relationship between Chi. a and COD. In the analysis of dendogram based on environmental parameters using SPSS ver. 10.0, the station 7 did not belong to other stations, and kept an independent place. The relationships of waters between Jindo, Wando and Heanam ware close, compared with other waters. Consequently, these regions except for Morkpo into which fresh water is introduced by the dike showed somewhat optimal environmental parameters and nutrients in year, and were assumed to maintain the desirable marine conditions for aquaculture.

• Korean Journal of Ichthyology
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• v.33 no.3
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• pp.184-190
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• 2021

Since the original description of new species, Eumicrotremus jindoensis, we confirmed the first occurrence of E. jindoensis based on a single specimen (22.3 mm SL) caught by inshore stow net at the coastal waters of Boryeong of Korea. However, our specimen slightly differed from type specimens in having more vertebrae (26 vs. 21~24), longer snout (17.4% vs. 8.1~9.1%), longer preanus length (67.5% vs. 58.0~58.3%) and shorter second dorsal fin base (15.3% vs. 20.2~20.8%). Comparing with mtDNA COI and Cytb sequences, we could not find any differences in mtDNA Cytb sequences between our specimen and type specimens, which suggest that those morphological differences may belong to local variation by habitat and environmental condition between off Jindo Island and off Boryeong in Korea. Eumicrotremus uenoi is known from the southern sea of Korea narrowly (Busan, Tongyeong, and Jeju Island), the other congeneric species (E. asperrimus, E. pacificus, and E. taranetzi) from only the eastern sea of Korea, but E. jindoensis from the central coast to southern coast of western Korea.

• Journal of Wetlands Research
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• v.7 no.2
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• pp.89-104
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• 2005

This study examined ecological grade of tidal flats at 59 sites along the west and east coast of Korea from January 1998 to December 2002. Assessment of ecological grade based on 7 headings includes biological and human geographical factors, such as species diversity and richness, utility value of species, possibility of damage and reservation conditions of coastline. Total of 181 species with 37 families of 14 orders were listed in this study. The highest scores (ecological grade I) showed at these five sites, Hagampo in Chungnam, Ui-do and Geomun-do in Jeonnam, Bijin-do and Maemul-do in Gyungnam. Half of thestudy sites belong to ecological grade II and 19 sites showed ecological grade III. Singyeong in Gyeonggi, Janghang in Chungnam, Gyehwado and Gomso in Jeonbuk, Dadepo in Busan were assessed as ecological grade IV. Grade V (the worst) was not found in this study.

• Korean Journal of Remote Sensing
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• v.28 no.2
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• pp.255-266
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• 2012

The enormous disaster (Friday nightmare) occurred at 14:46 (JST) (05:46 UTC) on 11 March 2011, officially named "the 2011 Tohoku Earthquake and Tsunami". To monitor the variations of the marine environment after the earthquake, we used chlorophyll and Rrs(555) of GOCI and MODIS ocean color satellite data during March ~ May 2011. Before the earthquake, chlorophyll and Rrs(555) were relatively low around the Sendai areas. After the earthquake;their concentration and intensity were suddenly increased along the coast and the water column was disturbed by the tsunami wave. The severe distortions influenced by the tsunami occurred at less than 30 m water depth and the variations in offshore were difficult to discern the effect of the tsunami. The disturbance by the tsunami was still remained in the terrestrial environment after one month. However the ocean environment returned to the former condition in almost two month later.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.520-523
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• 2005

국내에서 대체에너지 공급 비율을 보면 청정에너지로 분류할 수 있는 태양열에너지, 태양 광 에너지, 풍력에너지를 모두 합하여 대체에너지의 $10\%$이하이며, 대체에너지 비율의 $90\%$ 이상을 폐기물로부터 얻은 에너지가 차지하고 있는 실정이다. 신재생에너지원에는 여러 종류가 있지만 해양에너지원에 대해 대상을 설정하고 이에 대한 부존량을 살펴보면 진도 주변의 해역에서 조류발전 부존량이 약 362만 kW가 되며, 시화호와 새만금 등지에서의 조력발전 부존량이 650만 kW, 동해안 후포 연안을 비롯한 파력발전 부존량이 20만kW가 되는 것으로 알려져 있다. 이에 따라 해양에너지를 실용화하기 위한 연구가 국내외에서 연구되고 있다. 본 논문은 권선형유도발전기를 갖는 조류발전 시스템을 대상으로 연구한 결과로 권선형유도발전기를 제어하기 위한 전력변환장치 개발과 관련한 내용이다. 신재생에너지원이 발전 단가 측면에서 경제성을 갖기 위해서 발전기 용량은 5MW 급까지 대용량화되어 있는 단계이지만 국내에서는 아직 MW급 이상이 되는 권선형 유도발전기와 권선형 유도발전기를 제어하는 전력변환장치에 대한 연구 실적이 없는 상황이다 이에 본 논문에서는 1MW급의 권선형유도발전기에 대한 개발 사례를 소개하면서 유효전력제어, 역률제어, 계통연계방법, 그리고 운전 속도에 따라 변동되는 회전자측에서의 피상전력 특성 등을 제시하고자 한다.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.483-486
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• 2005

국내에서 대체에너지 공급 비율을 보면 청정에너지로 분류할 수 있는 태양열에너지, 태양광 에너지, 풍력에너지를 모두 합하여 대체에너지의 10% 이하이며, 대체에너지 비율의 90% 이상을 폐기물로부터 얻은 에너지가 차지하고 있는 실정이다. 신재생에너지원에는 여러 종류가 있지만 해양에너지원에 대해 대상을 설정하고 이에 대한 부존량을 살펴보면 진도 주변의 해역에서 조류발전 부존량이 약 362만 kW가 되며, 시화호와 새만금 등지에서의 조력발전 부존량이 650만 kW, 동해안 후포 연안을 비롯한 파력발전 부존량이 20만 kW가 되는 것으로 알려져 있다. 이에 따라 해양에너지를 실용화하기 위한 연구가 국내외에서 연구되고 있다. 본 논문은 권선형유도발전기를 갖는 조류발전 시스템을 대상으로 연구한 결과로 권선형유도발전기를 제어하기 위한 전력변환장치 개발과 관련한 내용이다. 신재생에너지원이 발전 단가 측면에서 경제성을 갖기 위해서 발전기 용량은 5MW 급까지 대용량화 되어 있는 단계이지만 국내에서는 아직 MW급 이상이 되는 권선형유도발전기와 권선형유도발전기를 제어하는 전력변환장치에 대한 연구 실적이 없는 상황이다. 이에 본 논문에서는 IMW급의 권선형유도발전기에 대한 개발 사례를 소개하면서 유효전력제어, 역률제어 특성과 운전 속도에 따라 변동되는 회전자 측에서의 피상전력 제어 특성에 대해 고찰하고자 한다.

• Korean Journal of Environmental Biology
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• v.34 no.1
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• pp.18-29
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• 2016

The effects of water temperature, salinity, water column nutrient contents, and phytoplankton primary productivity on pigment composition and concentration, as well as primary productivity of Pyropia yezoensis Ueda purple lavers were studied at the primary cultivation areas in the Manho (Jindo-Haenam) region on the southwestern coast of Korea in March 2014. The water temperature was $9.1{\sim}9.6^{\circ}C$, salinity was 32.5~33.1, and transparency was 0.7~1.5 m. The shallow euphotic depth resulted from the high turbidity. Water column dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP), and silicate concentrations were $3.59{\sim}5.73{\mu}M$, $0.16{\sim}0.41{\mu}M$, and $12.41{\sim}13.94{\mu}M$, respectively. Chlorophyll a (Chl a) concentration was $0.51{\sim}1.25{\mu}g\;L^{-1}$. Nanoplankton ($0.7{\sim}20{\mu}m$ size class) accounted for 58% of the total Chl a concentration. Fucoxanthin was the dominant photosynthetic pigment at all sites. Microplankton ($20{\sim}200{\mu}m$ size class) accounted for 64% of the total fucoxanthin concentration. The primary productivity of phytoplankton was $57.72{\pm}4.67(51.05{\sim}66.71)mg\;C\;m^{-2}d^{-1}$. The nanoplankton ($0.7{\sim}20{\mu}m$ size class) accounted for 77% of the total phytoplankton primary productivity. The calculated phytoplankton primary productivity was $11,337kg\;C\;d^{-1}$. The primary productivity of Pyropia blades was $1,926{\pm}192(1,102{\sim}2,597)mg\;C\:m^{-2}d^{-1}$, i.e., calculated as $39,295kg\;C\;d^{-1}$. The total primary productivity of phytoplankton and Pyropia blades was $50,632kg\;C\;d^{-1}$. The primary productivity of Pyropia blades was 3.5 times greater than that of phytoplankton in the Manho region on the southwestern coast of Korea.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.4
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• pp.404-418
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• 2013

In this study, we conducted field surveys to investigate and analyze species and length composition of catch from gape net with wings being set in two areas - Masari, Supomri - located in southern part of Jin-do for understanding fishing characteristics of gape net with wings fishery from March to September of 2011. And with those results, we attempted to propose fishery management strategy to harvest fisheries resources continuously. Catch obtained from field surveys comprised total 78 species, which accounted for 53 species of fish, 20 species of crustacean, 4 species of cephalopod and one of polychaete. As to species composition in weight, it showed that there was 88.5% for pisces, 9.0% for cephalopoda and 2.5% for crustacea. As to catch specifics by area, there was 36 species (596,891 individual, 456,551g) of pisces, 17 species (35,815 individual, 12,909g) of crustacea and 3 species (2,876 individual, 3,004g) of cephalopoda in Masari area. In Supumri area, there was 41 species (396,898 individual, 281,457g) of pisces, 15 species (16,113 individual, 7,772g) of crustacea and 4 species (6,792 individual, 72,329g) of cephalopoda and one polychaeta (36 individual, 11g). Catch of anchovy by month recorded on high level on June, July, September in both areas. When considering size composition by month, it was found that new populations recruit to these fishing grounds on June and September. Most of bycatch species including hairtail (Trichiurus lepturus), dotted gizzard shad (Konosirus punctatus), conger eel (Leptocephalous), Pacific sandlance (Ammodytes personatus), horse mackerel (Trachurus japonicus) were juvenile, and grass puffer (Takifugu niphobles), Kammal thryssa (Thryssa kammalensis), Japanese sardinella (Sardinella zunasi) were also small in size. As a result, it is considered that gape net with wings fishery which is likely to catch juvenile needs to be set fishing prohibit period for conserving above stocks during the period excluding main fishing periods of anchovy or fisheries management such as expanding mesh size for preventing juvenile catch.

• Ecology and Resilient Infrastructure
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• v.2 no.1
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• pp.64-79
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• 2015

We investigated the tidal current, hydrographic data, and benthic environment of major sea cucumber (Holothuroidea, de Blainville, 1834) habitats in Baengnyeongdo, Jindo and Uljin to understand the optimal environmental or ecological habitat for sea cucumbers. The three study areas were characterized by a cold-water mass of temperatures ranging $12{\sim}18^{\circ}C$, with an active circulation between the surface and deep waters. According to an analysis of the tidal current map, a strong flow velocity of $100{\sim}120cm\;s^{-1}$ appeared in Baengnyeongdo and Jindo. The three sea cucumber habitats showed the common characters of a bottom sediment composed of sand-silt, a diverse seaweed colony and benthic organisms, and boulders and rocks which provide a hideout for the organisms. We aimed to draw the optimal habitat condition for sea cucumbers in Korea, and the result showed that the low water temperature, rapid water flow, active vertical mixing between surface and deep waters, bottom composed by sand-silt, large rocks, and diverse seaweed colony and benthic organism were important factors. The optimal habitat for Juvenile sea cucumbers was the intertidal areas characterized by a muddy bottom, reef, and seaweed. The optimal habitat for adult sea cucumbers was characterized by a place where sand and mud are mixed, and the body size of the sea cucumber was proportional to water depth, and the relatively large boulders and rocks compared to the intertidal area.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.2
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• pp.101-110
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• 2013

In order to classify the trophic state and environmental quality of marine coastal system, an approach using the characteristics and biochemical composition in the sediments can be available. This research, including 25 coastal bay, belong to 131 stations, was carried out along the south coasts of Korea in February 2007. Type of sediment, total ogranic carbon, total nitrogen, phytopigments and biochemical composition(proteins, lipids, carbohydrates) were analyzed. Result from Multi-dimensional Scaling(MDS) ordination indicates that four group can be identified. The result of ANOVA with tukey test shows that the concentrations of proteins, carbohydrates and biopolymeric carbon were significantly different to four groups. We propose the trophic state classification for these groups using the biochemical composition of sediment organic matter. I group(Masan, Jinhae, Haengam) has been defined as hypertrophic state, II group(Tongyeong, Goseong；Jaran, Geoje et al.), as eutrophic; III group(Gamak, Deungnyang, Yeoja et al.), as mesotrophic and IV group(Sinan, Jindo, Muan), as oligotrophic. On the basis of results reported in this study, the biochemical composition of sediment organic matter could be considered an useful and sensitive tool for the classification of the trophic state of marine coastal systems.