• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.4
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• pp.276-284
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• 2000

Distributions of organic carbon (Co$_{org}$), organic nitrogen (N$_{org}$), and heavy metals (Zn, Pb, Cr, Cu, Mn) were investigated in Lake Shihwa sediments. Surface and core samples were collected in April and September, 1997 and March, 1998 for the study. The results show that these components contents are variable with sampling timeand station. In surface sediments, both Co$_{org}$ and N$_{org}$ have similar distribution pattern in which their high contents found in stations located near the land, indicating that the streams and industrial wastes seem to act as point sources. The C$_{org}$ contents are linearly related with those of heavy metals. It appears, therefore, that the distribution of heavy metals may be partly controlled by a complex interplay of biogenic, terrestial, and anthropogenic factors. The C/N ratios from three stations are in the range of 3-32, with an average of 13.2. Vertical profiles of heavy metals in sediment cores are similar to those of C$_{org}$ and N$_{org}$. Copper content of sediments is enriched compared to that of reported value before dike construction, but Zn and Mn are not deposited considerably. Especially, Pb content show less variable. Currently, anthropogenic effects of industrial complex may not reached to drainage gate area where heavy metal contents are comparable with those adjacent to coastal sediments.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.3
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• pp.186-194
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• 2000

In this study, the oceanic responses to given atmospheric boundary conditions are investigated using a mesoscale ocean circulation model. The numerical experiments are divided into two parts: One is, so called, spin-up experiment and the other is reproduction experiment. The spin-up experiment simulates climatic state of ocean by integrating the ocean model with upper boundary conditions of the monthly mean atmospheric climate data. In the reproduction experiment, for the reproduction of major oceanic changes around Korean Peninsula during the period of 1980-1998 (19 years), the model has been integrated under the boundary condition of the 19year monthly mean atmosphere data. The spined-up state of ocean generated from the spin-up experiment is assigned to the initial boundary condition of the reproduction experiment. In the spin-up experiment, the model properly simulates the major features of circulation structure around Korean Peninsula; such as separation of East Korean Warm Current (EKWC), formation of the polar front, cold water band associated with the small scale eddies in the East Sea, the formation of front along west coast, and the seasonal variation of circulation pattern caused by changing upwind current in the West Sea. In the reproduction experiment, the model has shown the interannual sea surface temperature variations and a warming trend of about 0.5$^{\circ}$C during the period around Korean Peninsula, as in the case of the observation. Therefore, it is concluded that the model is capable of simulating not only the mean states but also the variabilities of ocean under the given atmosphere boundary conditions.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.4
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• pp.335-345
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• 2000

Physical and acoustic properties of the Southeastern Yellow Sea Mud (SEYSM) of Korea were studied by using 10 piston cores. The data were also compared with mudbelt sediments in the South Sea and the East Sea (southeastern inner shelf) of Korea. The sediments were mainly composed of homogeneous silt. Sandy mud and mud were minor components. The major source of sediment in the study area is probably the Keum River. Finegrained sediments discharged from the river are transported southward by coastal current, resulting in a gradual southward increase in porosity and a decrease in wet bulk density and sound velocity. The mean grain size especially appears to be the most important variable to determine the physical properties and velocity. The variations of physical properties with burial depth are dependent more strongly on sediment texture (especially, silt content) than compaction and/or consolidation. Correlations between the physical properties and the sediment texture show slight deviations from those of the East Sea and the South Sea of Korea in spite of similar pattern within the limiting values. This is probably due to the differences in silt contents, sedimentary environments, mineral compositions, and gas contents.

• 한국해양학회지
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• v.9 no.2
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• pp.52-58
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• 1974

The water temperature distribution and the water movement closely related with it, in the east side of Korea, was condidered. Special emphasis was paid on the low temperature phenomenon near Ulgi. It was known from the temperature distribution in the east side of Korea that the Tsushima current continues to flow northward at the surface near Sokcho. Also the influence of the cold water extends from the North to the South with increasing depth. The formation of the cold core near Ulgi was explained as due mainly to the existence of the boundary layer near the surface, and partly to the effect of the wind. This inclination of the boundary layer has the value of about 3.0m/Km, and the lower cold current velocity computed using this value lies in the range of those observed by Nishida(1926, 1927). The upwelling velocity was computed approximately as 1.4 10$\^$-3/ cm/sec, and the maximum distance to which the boundarylayer can rise or fall from it's equilibrium position was considered as below 10m.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.2
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• pp.125-130
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• 2014

In order to evaluate the distributions of colloidal $^{210}Pb$ (half life = 22.2 years) and $^{210}Po$ (half life = 138 days) in subterranean estuary, we have measured $^{210}Pb$ and $^{210}Po$, for the first time, in the total dissolved (< $0.45{\mu}m$), true dissolved (<10 kDa), and colloidal ($10kDa-0.45{\mu}m$) phases in subterranean estuary of Hampyeong Bay in July 2010 and of Jeju Island in January 2011. The $^{210}Pb$ and $^{210}Po$ activities in groundwater were in the ranges of $0.21-2.52mBqL^{-1}$ and $0.12-2.07mBqL^{-1}$ for true dissolved phase and $0.10-1.71mBqL^{-1}$ and $0.03-0.97mBqL^{-1}$ for colloidal phase, respectively. The proportions of the colloidal phase to the total dissolved phase were $40{\pm}5%$ for $^{210}Pb$ and $28{\pm}5%$ for $^{210}Po$ in groundwater. This result indicates that colloids may play an important role in transporting trace elements through subterranean estuary into the coastal ocean.

• Journal of fish pathology
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• v.5 no.1
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• pp.29-35
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• 1992

This study was carried out in order to identify the biochemical and serological characteristics of Edwardsiella tarda isolated from cultured flounder, Paralichthys olivaceus in the east and south coast of Korea. During the year of 1990 and 1991, the number of isolated E. tarda were 131 strains. To identify the biochemical characteristics of them kinds of tests were conducted. The results represented that all the strains had the same biochemical characteristics, and their biochemical characteristics were no differences among strains. A serological analysis was carried out based on agglutination test with antiserum belonging to E. tarda serotype a (E-22), b (SU-138), c (SU-100) classfied in japan. The selected 10 isolates showed agglutinin titer of 5120-2560, 40-80 and below 40 against E. tarda serotype a, b and c, respectively. Sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE) profiles of cell proteins of selected 10 isolates were showed no differences in kinds and volumes of proteins among strains.

• Journal of Korea Water Resources Association
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• v.38 no.4 s.153
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• pp.323-332
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• 2005

The Tumen River basin is relatively small(${\approx}33,000km^2$), it has many potential conflicts between the riparian countries. Especially, until recently, it could have not drawn the socio-potitical attention from its central governments because of the geopolitical unique characteristics as edges of mainlands. since 1990's the various plans have been suggested for resolving the problems in this area as an international attention from, e.g UNDP, began to be given. However, the international cooperative structure has not been established in systematic way which has paramount importance. In the research, based on the problems identified in the previous paper, the necessities for independent unit, so called 'Tumen River Watershed Management Commission' were suggested for holistic and hierarchical resolution in accordance with integrated management and international river based on 'limited territory sovereignty' which is a general principle in international river management. For this purposes, hierarchical problem solving approach which consists of 3 phases were developed. They include major objectives and behavioral guidelines for achieving equity between riparian countries based on international cooperation and integrated watershed management as fundamental concept. In conclusion, rational plan for future water use, management and primary framework of Tumen River for international cooperation were composed and strategic approach for the North-East Asian community foundation was suggested.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.18 no.3
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• pp.198-210
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• 2006

POM(Princeton Ocean Model) was utilized in this study because it took ${\sigma}-coordinate$ system which could predict the behavior of bottom water. The model has been increasingly applied to costal area although it was initially developed as the ocean flow model. The original POM did not correct computational errors in transformation of ${\sigma}-coordinate$ system. The trying to reduce conversional errors might improve accuracy of flow velocity in vicinities of bottom layer. Therefore, in this study it was proposed to modify the original POM by using error correction method suggested by $Sl{\Phi}rdal$(1997). The modified POM was applied to Young-rang Lake, one of the typical brackish lakes in Korea. It was found that the behavior of bottom water could be well predicted. Thus, it seems that the modified POM can be used as a useful tool to clarify the mechanism of formation and behavior of bottom water including oxygen-deficient water mass.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.27 no.1
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• pp.63-77
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• 2015

Tsunami take away life, wash houses away and bring devastation to social infrastructures such as breakwaters, bridges and ports. The coastal structure targeted object in this study can be damaged mainly by the wave pressure together with foundation ground failure due to scouring and liquefaction. The increase of excess pore water pressure composed of oscillatory and residual components may reduce effective stress and, consequently, the seabed may liquefy. If liquefaction occurs in the seabed, the structure may sink, overturn, and eventually increase the failure potential. In this study, the bore was generated using the water level difference, its propagation and interaction with a vertical revetment analyzed by applying 2D-NIT(Two-Dimensional Numerical Irregular wave Tank) model, and the dynamic wave pressure acting on the seabed and the surface boundary of the vertical revetment estimated by this model. Simulation results were used as input data in a finite element computer program(FLIP) for elasto-plastic seabed response. The time and spatial variations in excess pore water pressure ratio, effective stress path, seabed deformation, structure displacement and liquefaction potential in the seabed were estimated. From the results of the analysis, the stability of the vertical revetment was evaluated.

• Economic and Environmental Geology
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• v.6 no.3
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• pp.171-182
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• 1973

Gemorphological and photogeological techniqes are applied to the problem of geological mapping of a semi-arid area, Albudeite, Southeastern Spain. As a result of this, a geological and surface materials map is made which shows the upper Miocene formation, which mainly consists of marl, limestone and sandstone, is further subdivided into three members, i. e. lower, middle and upper, and the post-Miocene deposits were differentiated into seven stratigraphic units, and mapped. The relationships between geology, landforms and land comlexes previously reognized have been reviewed. The methods adopted have proved to be valuable in interpreting and mapping a compex relationship in which highly variable bedrock outcrops and shallow surface materiales produced under sub-aerial conditios.