• Proceedings of the Korean Environmental Sciences Society Conference
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• 1998.04a
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• pp.187-189
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• 1998

• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.88.2-88
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• 1999

No Abstract, See Full Text

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.3 no.1
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• pp.29-37
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• 1991

A two-dimensional numerical model. using finite element method. was applied to calculation of the tides and tidal currents of four major tidal constituents($M_2, ;S_2, ;K_1, ;O_1$) in the southern part of the East Sea. The model results were compared with the observed data and with the existing tidal charts. and the computed results showed good agreement with the observation. As a result, the detailed tidal charts for four major tidal constituents and the tidal current ellipses of the M$_2$and $K_1$tides were produced respectively. The results indicate that the amphidromic point of diurnal tide locates near Korean coastal lines closer than that of the chart drawn by Nishida(1980).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.1
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• pp.35-41
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• 2015

The age and growth of the Marbled sole, Pleuronectes yokohamae were investigated using left sagittal otoliths of 832 individuals collected in the mid-southern waters of Korea from January 2006 to April 2007. The seasonal changes in the ratio of an translucent zone to interval between annular rings revealed that the boundaries between translucent and opaque parts of the otolith were annual growth rings formed between May and June once a year. The spawning period was November to March and therefore the duration from fertilization to the complete formation of the annual growth ring became fifteen months. The parameters of von Bertalanffy growth equations estimated using the average standard length at each age are the $L_{\infty}$ of 48.04cm, K of 0.1406/year and $t_0$ of -0.5116 for female and 26.14cm, 0.3056/year and -0.8202 for male, respectively. Finally, it is suggested that the growth of female is faster than that of male from age-2.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.6 no.1
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• pp.109-116
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• 1994

Tsunamis generated by of the 1992 Flores Island Earthquake in Indonesia caused tremendous casualties and damages. This tsunami event was hindcasted via numerical tsunami models. Initial conditions were taken from fault parameters from Havard CMT (Centroid Moment Tensor) solution and additional subaqueous slump consideration at the Inner Hading Bay and Riang Krok, Leworahang coasts. The computed results showed general agreements with observations made by the International Tsunami Survey Group. Subsequently a runup model was developed to investigate catastrophic runup at southern shore of the Babi Island with fine grid resolution of 50 m. Computed results were recorded to construct rendered images for video animation. The computer-graphic aided video animation showed a remarkable reproduction of tsunami propagation and runup at southern coast of the Babi Island.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.3
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• pp.194-202
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• 2011

Maturation and spawning of the Shotted halibut, Eopsetta grigorjewi was investigated based on the samples captured in South Korean waters from January 2008 to December 2009. Gonadosomatic index began to increase in December, and reached maximum between January to March. After spawning it began to decrease from May. Reproductive season was estimated to January-April, with peak in February. Fecundity was proportional to the size of the female, with the clutch size varying from 170,000 eggs in the smallest female (total length, 28.9cm) to 1,300,000 eggs in the largest (total length, 41.5cm). Size at 50% sexual maturity (TL50), determined from mature females, was 28.8cm. Annual reproductive cycles of this species could be divided into six successive stages; immature stage (May-October), nucleolus stage (November-January), yolk vesicle stage (January-February), vitellogenic and ripe stage (January-April) and spent stage (April-May).

• Ocean and Polar Research
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• v.24 no.4
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• pp.331-343
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• 2002

The southern tidal flat of Kanghwa Island with an area of approximately $90km^2$ is one of the biggest flats on the west coast of Korea. Surface sediments for sedimentary analyses were sampled at 83 stations in August 1997, September 1999 and August 2000. The very poorly-sorted mud sediments were predominant in the eastern part of the tidal flat, whereas the poorly-sorted sand-mud mixed sediments were dominant in the western part. The area of muddy sediment distribution diminished, but that of sandy mud sediment extended to southeastward tidal flat for three years. In the western part of tidal flat, deposition occurred during the period of spring to summer, whereas erosion occurred in winter. Sediment accumulation rates during three years indicated that the sediments deposited continuously in the eastern part of tidal flat, whereas eroded in the western part of tidal flat. Recently, construction of artificial structures such as new airport, island-connecting bridges and dikes near the tidal flat might change tidal current and river flow pattern. In order to reduce the ecological damage and to preserve tidal-flat environment, it is necessary to Investigate long-term impacts on sedimentary environment and ecology.

• Ocean and Polar Research
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• v.35 no.1
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• pp.51-61
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• 2013

Two surveys were conducted in January 2006 and September 2007 with multibeam echosounder to investigate the dune shape, migration rate, and bedload transport rate using dune-tracking method on an offshore sand ridge at southern Gyeonggi Bay. The migration rates of dunes range from 1.8 $myr^{-1}$) to 56.0 $myr^{-1}$), at the upper northwestern side of sand ridge towards the southwest direction and from the center of the sand ridge towards the northeast direction respectively. Large (i.e. length 10-100 m) dunes show faster migration (0.3-23.4 $myr^{-1}$) ) than very large (i.e. length > 100 m) dunes because larger dunes have required a larger volume of sediments to be displaced. The decreases in dimensions and migration rates of dunes from the center of sand ridge to the lower part of southeastern side on the sand ridge can be ascribed to the decrease of sandy sediments availability, tidal currents with depth, and the coarsening of surface sediments from the crest of the sand ridge to the trough. Bedload transport rates on the basis of migration rates and dune dimensions decrease from 74.5 $m^2yr^{-1}$) at C transect to 35.6 $m^2yr^{-1}$) at R-02 transect.

• Journal of Korean Society on Water Environment
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• v.21 no.5
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• pp.496-499
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• 2005

Power Plant is requested, by environmental bodies and fisherman, to correct the pollution of coastal area due to the outflow of foam from the outlet of the power plants. Foam wastewater cause a lot of environmental problems, expecially in aesthetic points of view. Therefore, It is needed to be collect from the stream into nearby ocean, and the collected foams should be treated before being discharged into nearby ocean. The most effective and feasible treatment method researched for the effective treatment of foam wastewater generated at the power plants. The result of the test is confirmed with collecting Foam wastewater by inhalation force. The treatment pilot ($3m^3/hr$) collected wastewater was operated by Biological degradation method(Aerobic/anaerobic Processes) for approximately two months. It was removed SS, COD, nutrient(T-P, T-N), etc. The System is expected successfully by Minimizing the operating costs such as electricity, repair expenses, chemicals and supplies expenses.

• Journal of Ocean Engineering and Technology
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• v.14 no.3
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• pp.1-10
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• 2000

In order to effective manage the construction, disaster prevention plan and the harbor tranquility control, meteorological and sea-state characteristics around Cheju Island have been analyzed. Using results and damage examples of the port facilities under severe sea conditions, a reasonable construction control plan considering the regional characteristics of the sea-state and winds was proposed. That is, in northern part of Cheju Island, the construction work is affected mainly by the winter storms, while the typhoon mainly affects the southern part port facilities during summer to Autumn. Considering their typical characteristics, it is strongly suggested that the main construction work should be carried out during April to July in the northern part, and it should be made during October to next July in the southern part of the island. A permeable TTP mounded breakwater was constructed to protect severe waves as a temporal structure under the long-term development plan in Sogipo port. The transmission characteristics of the structure was discussed using the experimental results. The results show that the transmission coefficient $K_{t}$ is over 20% of incident waves, which cause many problems in the cargo handling in relation to harbor tranquility. In conclusion, this kind of permeable structure can be used only as a temporal structure for the disaster prevention under the construction process. It causes many problems in harbor tranquility if it is used as a permanent harbor structures.s.