• 한국환경과학회지
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• 제11권12호
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• pp.1299-1305
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• 2002

Thirty sediment samples of the <63${\mu}{\textrm}{m}$ fraction collected from the southwestern coast of Korea were analysed for their heavy metal (Fe, Mn, Cr, Co, Cu, Ni, Zn and Pb) concentration. The results show that sediment texture plays a controlling role on the total metal concentrations and their spatial distribution. A single lM HCl extraction procedure was used in order to assess the environmental risk of heavy metals in bottom sediments. The non-residual fraction was the most abundant pool for Mn and Pb in most samples, which means that this metals are highly avaliable in these sediments. Cr, Ni, Fe, Co, Zn and Cu were mainly associated with the residual fraction, suggesting that their concentrations are controlled significantly by transport processes with the fine particles as carriers from diffuse pollution source. Concentration enrichment ratios(CER) were calculated from the non-residual contents and their values allowed us to classify the sediments according to their environmental risk.

• Journal of the korean society of oceanography
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• 제34권3호
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• pp.172-178
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• 1999

An overview of the spatial and seasonal patterns of phytobenthic communities is described from the intertidal zone at Hawon-Pando on the southwestern coast of Korea based on quantitative and qualitative estimates of macroalgae. There were considerable variations of macroalgal diversity and cover value with the intertidal levels. Tn general, the number of species decreased with increasing intertidal height. The upper region was dominated by Sargassum thunbergii. S. thunbergii and crustose red algae were dominant in the mid intertidal habitat. In the lower intertidal Corallina pilulifera and crustose red algae were the conspicuous dominants. Macroalgal community structure at Hawon-Pando is discussed in the context of functional-form groups. The Hawon-Pando intertidal is characterized as consisting of a relatively high cover of species assigned to the thick leathery, crustose and jointed calcareous groups, and is distinguished by a paucity of the filamentous group.

• Ocean and Polar Research
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• 제21권2호
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• pp.87-97
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• 1999

To estimate absolute transports by advection in the southwestern East Sea (Japan Sea), an inverse method was applied to CTD data obtained in July 1993. The relative velocities are calculated using the thermal wind equation. The inverse model was formulated to obtain a reference velocity based on the mass conservation in each of four vertical layers within a region enclosed by hydrographic sections and the coastal boundary. The flow patterns in the surface layer are clockwise and anti-clockwise in the regions south and northwest of Ulleung Island, respectively, and a strong northward flow appears in between them. In the second layer, the flow fields are generally weak. The inverse calculation yields the southward flow along the coast, and this suggests that the subsurface low salinity water in the Ulleung Basin is supplied by the southward transport along the east coast of Korea.

• 한국환경과학회지
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• 제8권6호
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• pp.677-684
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• 1999

To investigate size distribution and metallic elements of surface sediments in Hampyong Bay, the southwestern coast of Korea, sedimentological and geochemical studies on surface sediments are carried out. The surface sediments of Hampyong Bay are classified into gravel, muddy sandy gravel, gravelly muddy sand, gravelly sandy mud, mud facies in accordance with areal characteristics. The coarse sediments are distributed on the subtidal zone along the main tidal channel and southeast intertidal flat of Hampyong Bay. On the other hand, the fine sediments are dominated in northeast and west intertidal flat of Hampyong Bay. Most metallic elements except for Ba in the sediments are closely interrelated with fine sediments and mutually with each element. Ba is maybe related with sandy sediments and inversely related with carbonate contents. Normalized by Al content, the sediment do not show any remarkable metal enrichments influenced by resonable artificial or environmental factors.

• 한국해안·해양공학회논문집
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• 제20권1호
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• pp.14-24
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• 2008

목포와 제주를 위시한 서남해안에서 최근 예측 고조위가 증가하는 경향을 보이고 있다. 조화분석을 통한 자료분석 결과 서남해안 전반에 걸쳐 평균해수면이 뚜렷하게 증가하는 반면 반일주조의 진폭은 감소하는 것으로 나타나고 있다. 또한 태양연주조(Sa분조)의 진폭이 증가한 것으로 나타나고 있으며 이에 따라 하절기의 고조위가 더욱 상승한 것으로 확인되었다. 21세기 들어 RUSA와 MAEMI등 대형 태풍의 발생이 잦아지고 있어 1990년대에 비해 서남해안에서의 최대해일고가 크게 증가하였다. 또한 이들은 7월${\sim}$9월에 집중되고 있어 하절기 고조위 상승과 함께 이상고조위 발생 가능성을 더욱 우려스럽게 하고 있다. 특히 목포해역은 하구언과 방조제 건설이후 이상고조 발생 가능성이 현격히 높아진 해역이므로 더욱 그러한 실정이며, 평균해수면 상승경향이 매우 뚜렷한 제주해역 역시 향후 이상고조 발생 가능성이 매우 높을 것으로 판단된다.

• Journal of Electrical Engineering and Technology
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• 제9권3호
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• pp.820-826
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• 2014

It is well known that energy generated by a wind generator (WG) depends on the wind resources at the installation site. In other words, a WG installed in a high wind speed area can produce more energy than that in a low wind speed area. However, a WG installed at a low wind site can produce a similar amount of energy to that produced by a WG installed at a high wind site if the WG is designed with a rated wind speed corresponding to the mean wind speed of the site. In this paper, we investigated the power curve of a WG suitable for Korea's southwestern coast with a low mean wind speed to achieve a high capacity factor (CF). We collected the power curves of the 11 WGs of the 6 WG manufacturers. The probability density function of the wind speed on Korea's southwestern coast was modeled using the Weibull distribution. The annual energy production by the WG was calculated and then the CFs of all of the WGs were estimated and compared. The results indicated that the WG installed on the Korea's southwestern coast could obtain a CF higher than 40 % if it was designed with the lower rated speed corresponding to the mean wind speed at the installation site.

• 한국항해항만학회지
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• 제29권4호
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• pp.327-333
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• 2005

Sea level (MSL, MHWL, or MLWL) change has been main concern to scientists and engineers and it can be primarily due to both change of climate and vertical movement of land. This paper reports the intensive analysis of the sea level changes and broad discussion of the future at the southwestern coast of Korean peninsula. Regression analysis was conducted to investigate general tendency and periodicity of the sea levels at the six different study sites such as Gunsan-I(inner port), Gunsan-O(outer port), Mokpo, Yeosu, Heuksan and Jeju and the results were compared with global values. Besides the changes of sea levels due to global warming, the influence of the man-made structure such as seadike and seawall was attempted to quantify using the minimization of the Root Mean Square(RMS) error. The results show that it is a general tendency that the values of mean sea level rise at the southwestern coast of Korean Peninsula, especially at Gunsan-I and Jeju, are somewhat larger compared to global average values. There is also some evidence that tidal amplifications are found just after construction of man-made structure at Gunsan-I and Mokpo. However, both sites show different mechanism in relation to tidal choking, tidal flat and river discharge. The impact due to construction of man-made structure is considerably larger at Mokpo site, while the impacts due to man-made structure and the effect of sea level rise are relatively identical at Gunsan-I site. This study is expected to provide some intuition to future design.

• 환경생물
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• 제36권4호
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• pp.610-619
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• 2018

본 연구는 한국 남서해안 갯벌 중 유부도, 곰소만, 임자도, 여자만 갯벌의 저서돌말류 종조성 및 생물량을 알아보기 위해 2016년 8월과 9월에 현장조사를 실시하였다. 유부도 갯벌에서 저서돌말류는 48속 181종, 곰소만 갯벌에서 51속 194종, 임자도 갯벌에서 64속 224종, 여자만 갯벌에서 56속 188종이 출현 하였으며, 총 70속 274종이 출현하였다. 분류군 가운데 중심돌말목보다 우상돌말목이 다양하게 출현하였고 우점종은 중심돌말목의 Paralia sulcata와 Navicula spp.였다. 유부도 갯벌의 생물량은 정점별로 $18.8{\sim}136.1mg\;m^{-2}$, 곰소만 갯벌 $31.9{\sim}215.7mg\;m^{-2}$, 임자도 갯벌 $2.9{\sim}120.2mg\;m^{-2}$, 여자만 갯벌 $10.1{\sim}147.7mg\;m^{-2}$, 4개 지역의 총 생물량 범위는 $2.9{\sim}215.7mg\;m^{-2}$였다. 엽록소 a의 분해 산물인 phaeopigment 농도로는 유부도 갯벌에서 $1.7{\sim}470.8mg\;m^{-2}$, 곰소만 갯벌에서 $52.3{\sim}277.2mg\;m^{-2}$, 임자도 갯벌에서 $0.6{\sim}78.9mg\;m^{-2}$, 여자만 갯벌에서 $39.1{\sim}346.3mg\;m^{-2}$으로 나타났다. 조사 대상지역의 종 다양성과 생물량은 높은 경향을 나타내었다. 한국의 남서해안은 다양한 저서돌말류가 서식하며 엽록소 a의 높은 농도는 일차생산력을 결정하는 주요인자다.

• 자원환경지질
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• 제4권1호
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• pp.11-18
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• 1971

The geotectonics and geomorphic structure of Korea resulted from the Song-rim Disturbance and the Daebo orogenic movements. Afterward this mountainous peninsula underwent several geological changes on a small scale, and it was also claimed that the steady rising of the elevated peneplain of the eastern coast and the submerging of the southwestern coastal area are largely due to the tilted block movement. These views have been generally accepted good in several ways, but they are limited in range or lacking in theoretical integration. The present writer investigated the geology of the Mt. Chi-ri-san and the Honam coal mining area for a geological map in 1965, respectively. The results of these studies convinced the present writer that the conventional views, which were based upon a theory of lateral pressure should be reconsidered in many respects, and more recent studies made it clear that the morphological development in the southwestern area can be better explained by the orogenic movement and rock control. The measurement of submerging speed of the western coastal area (Pak. Y. A., 1969) and a new account on the geology and tectonics of the Mid-central region of South Korea (Kim O.J., 1970) act as an encouragement to a new explanation. The present writer's researches on the extreme southwestern portion of the peninsula show that the steady submerging of this area cannot be attributed to a simple downthrown block phenomenon caused by block movement. It is no more than the result of the differential movement of uplifting in the eastern and western coastal areas and the rising of sea-level in the post-glacial period. This phenomenon could be easily explained by the comparison of the rate of rise in sea-level and amount of heat flow between Korea and other areas in the world. The existance of the erosional planes in the Sobaik-San ranges also provide an evidence of an upheaval in the western coast area. Though the Sobaik-San ranges largely follow the direction of the Sinian system. They consist of the numerous branches, whose trends run more or less differently from their main trend because of the disharmonic folding, are converged into Mt. Sobaik-San and Chupungryung. The undulation of the land is not wholely caused by orogenic movements, where as the present writer confirmed that the diversity of morphological development is the direct reflection of geological conditions such as rocks and processes which constitute the basic elements of geomorphic structure. An east-west directed mountain range which could be named as Hansan mountain range, was claimed to be oriented by the joint control. The geological conditions such as a special erosion and weathering of agglomerate and breccia tuff usually produce pot-hole like submarine features which cause the whirling phenomenon at the southwestern coast channel.

• 한국항해학회지
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• 제21권4호
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• pp.39-47
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• 1997

We researched the mechanism on th flucturain of Bottom Cold Water in the western channel of Korea Strait, using 13 years(1981~1933) oceanographic data of FRDA. The bottom cold water in the western channel appears more often in summer and fall than in winter and spring, and its year-to-year variation of temperature is very large. Such variation seems to be closely related with the variations of cold waters in the subsurface layer of the southwestern East Sea. According to the longitudinal temperature distribution along the korean southeastern coast, a density difference occurs all the time at the still deepth between the western channel and the southwestern East Sea. Thus, it is inferred that the cold waters would intrude into the western channle form the subsurface layer in the southwestern East Sea as a density-driven current, and it intensity depends upon the density difference.