• Computers and Concrete
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• v.19 no.4
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• pp.339-346
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• 2017

The main objective of this paper was to illuminate the effect of marine environmental condition on durability of reinforced concrete (RC)-corroded columns strengthened with carbon fiber reinforced polymer (CFRP) and glass fiber reinforced polymer (GFRP) layers. Small-scale columns were prepared and corroded by an accelerated corrosion process. After strengthening, compressive strength tests were carried out on control and weathered specimens. In this research, a marine simulator was designed and constructed similar to the tidal zone of marine environment in south of Iran which was selected as a case study in this research. Mechanical properties of wrapped specimens were studied after placing them inside the simulator for 3000 hours. Marine environment decreased ultimate strength by 4.5% and 26.3% in CFRP and GFRP-wrapped columns, respectively. In some corroded-columns, strengthening was carried out after replacing damaged cover by self-compacted mortar. In this method, by confining with one layer of CFRP and GFRP, 4.2% and 22.4% reduction in ultimate strength was observed, respectively, after exposure. Furthermore, the elastic-brittle behavior has been verified in this retrofit method. Also results of tension tests revealed, the ultimate tensile strength was degraded by 2% and 28.8% in CFRP and GFRP sheets, respectively, after applying marine exposure.

• Ocean and Polar Research
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• v.28 no.3
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• pp.287-290
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• 2006

Eye growth and lens diameter of brown croaker Miichthys miiuy were positively allometric between hatching and 180 days post-hatch (d.p.h.). Eye growth in relation to head length and head height was nearly isometric. Eyes were formed completely at 14 d.p.h. At this age, the eye has a crystalline lens, an optic nerve fiber layer, a ganglion cell layer, an inner plexiform layer, an inner nuclear layer, an outer plexiform layer, an outer nuclear layer, an outer limiting membrane, and a pigment epithelium. The essential demands that must be met by the retina in this species pertain to light sensitivity and spatial resolution.

• Journal of the Economic Geographical Society of Korea
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• v.11 no.4
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• pp.618-630
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• 2008

There are islands about 3,200 in Korea surrounded by the sea side. The region of islands is the transition areas which are a border in the land and marine ecosystem. It is rich in biodiversity depending on the interaction among inland, sea and atmosphere. However, it is worried that damages of marine environment is increased because the more national income and demands ofmarine leisure increase, the more development projects are grown in marine areas. Also this trends are extending in island areas. Incheon Metropolitan city has huge island areas which are both inhabited and deserted islands. The range of island areas is very wide, so it is difficult for the city government to manage environment in the island areas. Therefore, this paper analyzed and discussed the actual conditions about managing marine environment at island areas.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.3
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• pp.262-277
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• 2024

The mid-eastern coast of Korea is located at the boundary between cold and warm currents, which causes changes in the distribution and composition of marine organisms in response to fluctuations in the marine environment. To understand the seasonal changes in the seaweed community, we investigated its species composition, biomass, coverage, and frequency from November 2022 to August 2023. A total of 45 species (7 green, 18 brown, and 20 red algae) were found in the study area. In the intertidal zone, the number of species decreased from autumn to summer; the biomass peaked during winter (471.94 g wet weight m^-2). Seaweed groups were the dominant functional groups, which were coarsely branched, filamentous, and sheet-like during autumn, winter, spring, and summer. The morpho-functional group was dominated by turf species. In the subtidal zone, the number of species increased during autumn to spring, whereas the biomass peaked during spring (655.27 g wet weight m^-2). The functional group was dominated by coarsely branched species throughout all four seasons, whereas the morpho-functional group was dominated by canopy species. Consequently, changes in the biomass of brown and red algae are recognized as key drivers of seasonal changes in seaweed communities.

• Fisheries and Aquatic Sciences
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• v.7 no.3
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• pp.141-147
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• 2004

Sixteen polycyclic aromatic hydrocarbons (PAHs) were analyzed in seventy marine organisms (40 species) from the Korean coast. PAHs were present in all the organisms. The level of total PAHs in the organisms varied from 0.45 to 224 ng/g dry weight and the carcinogenic PAHs varied from 0.05 to 49.8 ng/g dry weight. The PAHs residues according to the marine organisms showed a highest content in bivalve species, and followed by crustaceans, cephalopods, fish and gastropods. Human dietary intake of total PAHs through marine organism in Korea was estimated to be 4.12 ng/kg body weight/day and 0.67 ng/kg body weight/day for carcinogenic PAHs. The relative contributions of individual species to the total dietary intake of PAHs were in the order of bivalves $(53.4{\%})$, fish $(21.9{\%})$, crustaceans $(15.3{\%})$, cephalopods $(8.8{\%})$ and gastropods $(0.6{\%})$. Daily dietary intake of $PAH_{TEQ}$ expressed as a TEQ value was estimated to be 0.13 pg TEQ/kg body weight/day, which did not exceed a tolerable daily intake (TDI) proposed by the KFDA and the WHO as well as the UK toxicity committee. Lifetime cancer risk due to ingestion of marine species by the Korean adult was evaluated using the equation estimating exposure of food ingestion. Although approximately $23{\%}$ of cumulative frequency of the sampled marine species exceeded the cancer risk guideline, lifetime cancer risk associated with marine organism consumption was negligible. Results indicate that dietary intake of PAHs through the consumption of the Korean marine organisms seems to be safe for human ingestion with negligible cancer risk.

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.3
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• pp.219-225
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• 2008

Since July 2006, marine traffic safety management system have been enforced to support the vessels transiting across the coastal area and the vessels coming in and out of ports in southwestern coastal area where heavy traffic density and marine casualties occurred frequently. The marine traffic volume for the marine traffic environmental assessment was measured by the information from RADAR and AIS system in the area. The distributions of marine casualties were analyzed in the main routes and traffic separation schemes during the last five years and the navigational dangerous elements were investigated with the influence of natural environment, the distribution of fisheries and survey questionnaire. Marine accidents of merchant ships have a tendency to decrease gradually but in case of fishing boats, the rate of marine accidents have a contrary results in this area during the last five years. The dangerous elements on navigation appeared to be the dense force from June to August, fisheries activities and the vessels which not follow the compulsory watch on VHF-band radio communication equipments.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.1
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• pp.49-55
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• 2010

Marine oil spill accidents not only devastates marine ecosystem but also Ins significant adverse socio-economic impact on local community whose living is dependent on clean marine system Although the Marine Environment Management Act of the Republic of Korea stipulates tim marine pollution impact survey must be conducted at the time of the oil spill, the articles do not provide specifics or concrete survey items for socio-economic impact assessment Moreover, there are redundancy questions in the provisions related to socio-economic impact assessment. This paper examined several difficulties encountered in carrying out the socio-economic impact assessment for marine oil spill as required in the law, and presented some recommendation., for the plan to improve the assessment mechanism systematically through the development of the research categories and indicators of socio-economic impact assessment.

• Journal of the Korean Society of Marine Environment & Safety
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• v.10 no.2 s.21
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• pp.29-34
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• 2004

The marine traffic congestion has increased due to the expansion of vessel traffic volume in Korean coastal waterway these days. Heavy traffic could bring serious marine casualties which cause the loss of human lives, properties and marine pollution in coastal area. In this paper, the probability analysis of marine casualties in Korean coast. To achieve this aim, clears up the cause of accident and examines closely the mutual relations among marine casualties, weather condition, and marine traffic volume. These casualties are classified into several patterns or the point of view of ship's size, ship's type and ship's age and its characteristics of each pattern are described In detail.

• Journal of Environmental Science International
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• v.25 no.8
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• pp.1087-1095
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• 2016

The concepts of residence time and flushing time can be used to explain the exchange and transport of water or materials in a coastal sea. The application of these transport time scales are widespread in biological, hydrological, and geochemical studies. The water quality of the system crucially depends on the residence time and flushing time of a particle in the system. In this study, the residence and flushing time in Gamak Bay were calculated using the numerical model, EFDC, which includes a particle tracking module. The average residence time was 55 days in the inner bay, and the flushing time for Gamak Bay was about 44.8 days, according to the simulation. This means that it takes about 2 months for land and aquaculture generated particles to be transported out of Gamak Bay, which can lead to substances accumulating in the bay. These results show the relationships between the transport time scale and physical the properties of the embayment. The findings of this study will improves understanding of the water and material transport processes in Gamak Bay and will be important when assessing the potential impact of coastal development on water quality conditions.

• Journal of the korean society of oceanography
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• v.36 no.4
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• pp.101-108
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• 2001

Polybrominated diphenylether (PBDEs) congeners, 2,4,4'-TrBDE, 2,2',4,4'-TeBDE, 2,2',4,4',5-PeBDE, 2,2',4,4',5,5'-HXBDE, and 2,2',4,4',5,6-HxBDE, were measured in sediments from 52 stations in the southeastern coastal areas of Korea. Sediment samples were analyzed using gas chromatography coupled to mass spectrometer detector (GC/MSD) with positive electron impact (PEI) mode. New analytical methodology for PBDEs by the isotope dilution method was established using a multi-layer silica gel column chromatography. Total PBDEs levels in sediments for Pohang coast ranged from 1,1 to 33.8 ng/g dry weight (mean 5.3 ng/g dry), from 1.6 to 36.4 ng/g dry weight (mean 5.7 ng/g dry) for Ulsan coast, from 0.8 to 20.3 ng/g dry weight (mean 4.9 ng/g dry) for Busan coast, and from 0.8 to 10.3 ng/g dry weight (mean 4.4 ng/g dry) for Jinhae Bay. PBDEs contamination in surface sediments from Korean southeastern coasts was relatively moderate in comparison to that of other marine environment in the world. The predominant PBDE congeners were 2,2',4,4'-TeBDE and 2,2',4,4',5-PeBDE.