• 신재생에너지
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• 제3권2호
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• pp.3-10
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• 2007

Tidal regime change with general hydrolic condition change is examined, according to Garolim Tidal Power Plant (TPP) operation. Numerical model has been developed for the Yellow and East China Seas region, in order to consider the tidal regime change by the TPP operation. The changes of tidal elevation and tidal current inside the Garolim bay are also investigated in details, along with examining the change of the tidal flat area with operation. The field measurement for the tide and current have been carried out for the validation of the numerical model and for understanding the state of current system in the present state.

• 천문학회지
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• 제23권2호
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• pp.97-105
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• 1990

The tidal radii of globular clusters reflect the tidal field of the Galaxy. The mass distribution of the Galaxy thus may be obtained if the tidal fields of clusters are well known. Although large amounts of uncertainties in the determination of tidal radii have been obstacles in utilizing this method, analysis of tidal density could give independent check for the Galactic mass distribution. Recent theoretical modeling of dynamical evolution including steady Galactic tidal field shows that the observationally determined tidal radii could be systematically larger by about a factor of 1.5 compared to the theoretical values. From the analysis of entire sample of 148 globular clusters and 7 dwarf spheroidal systems compiled by Webbink (1985), we find that such reduction from observed values would make the tidal density (the mean density within the tidal radius) distribution consistent with the flat rotation curve of our Galaxy out to large distances if the velocity distribution of clusters and dwarf spheroidals with respect to the Galactic center is isotropic.

• Ocean Science Journal
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• 제42권3호
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• pp.153-163
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• 2007

This study is based on a series of numerical modeling experiments to understand the tidal circulation in the Kangjin Bay (KB). The tidal circulation in the KB is mostly controlled by the inflow from two channels, Noryang and Daebang which introduce the open ocean water into the northern part of the KB with relatively strong tidal current, while in the southern part of the KB, shallowest region of the entire study area, weak tidal current prevails. The model prediction of the sea level agrees with observed records at skill scores exceeding 90 % in terms of the four major tidal constituents (M2, S2, K1, O1). However, the skill scores for the tidal current show relatively lower values of 87, 99, 59, 23 for the semi-major axes of the constituents, respectively. The tidal ellipse parameters in the KB are such that the semi-major axes of the ellipse for M2 range from 1.7 to 38.5 cm/s and those for S2 range from 0.5 to 14.4 cm/s. The orientations of the major-axes show parallel with the local isobath. The eccentricity values at various grid points of ellipses for M2 and S2 are very low with 0.2 and 0.06 on the average, respectively illustrating that the tidal current in the KB is strongly rectilinear. The magnitude of the tidal residual current speed in the KB is on the order of a few cm/s and its distribution pattern is very complex. One of the most prominent features is found to be the counter-clockwise eddy recirculation cell at the mouth of the Daebang Channel.

• 한국해안해양공학회:학술대회논문집
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• 한국해안해양공학회 2002년도 한국해안해양공학발표논문집 Proceedings of Coastal and Ocean Engineering in Korea
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• pp.208-211
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• 2002

The Kyunggi Bay (125-l28E, 36-38N) is a macro-tidal bay in the western central port of Korean Peninsula(Fig. 1). The Bay characterizes its feature as wide tidal flats, deep tidal channels and tidal sand ridges running in parallel to tidal flows. The macro-tidal range (up to approximately 8.6m) and consequent strong tidal currents erode the bottom sediment and selectively transport to the low-energy area forming tidal ridges or tidal flats. (omitted)

• 전기학회논문지P
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• 제63권2호
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• pp.113-118
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• 2014

Tidal power is one of new and renewable energy sources. Tidal power is generated by using the gap in the water level between the water outside and inside the embankment. All tidal power plant in Korea were being operated by import of turn-key from abroad. The know-how and technology which are the most important to build predictive control system has become increasingly difficult to obtain from advanced countries because most of them avoid to transfer, which the domestic development of the control system is needed. In this paper, a study on start stop system at water turbine-generator for tidal power plant at the beginning of development was presented. For improvement the efficiency and develope of core technology of the start stop system, the technique and characteristics of tidal power, modeling, maximum generation calculation method, and optimal control of joint control system in Sihwa tidal power plant were studied.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.513-516
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• 2006

The feasibility study for tidal power plant (TPP) has been carried out for the Siwha area inside the Kyunggi bay of the Kyunggi Bay of the Yellow and East china Seas, by KORDI (Korea Ocean Research and Development Institute) and continuing research works for tidal energy development are under progress in the several sites inside the Kyunggi Bay. In this paper we describes some results of the modeling efforts in relation the tidal regime change by Siwha TPP operation, as well as other coastal oceanographic research works involved in TPP development in the coastal region.

• 한국해안·해양공학회논문집
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• 제22권5호
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• pp.333-343
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• 2010

목포해역에서 조위와 조류 관측자료를 분석하여, 낙조류 우세 조류특성을 보이는 것을 확인하였으며 낙조류 우세를 발생하는 물리적 요인에 대해 검토하였다. 노출한계수심, 바닥마찰응력 산정방법, 해안 매립, 조석의 진폭, 비선형 조석, 와점성계수와 목포해역의 낙조류 우세현상의 관련성에 대해서 2차원 해수유동 모형을 적용하여 자세히 조사하였다. 다양한 조건에 대한 모의결과로부터 노출한계수심과 와점성계수는 모의결과에 거의 영향을 주지 않으며, 바닥마찰응력이 증가함에 따라 조류의 비선형성이 증가하여 낙조류 우세현상이 나타나는 것을 확인할 수 있었다. 간사지가 미치는 영향은 간사지가 육지로 바뀌면 낙조류 우세가 심해지고, 간사지가 바다로 바뀌면 낙조류 우세가 사라지는 것을 확인할 수 있었다. 그동안 목포해역에서 진행되어온 해안매립사업은 낙조우세현상을 심화시켜 왔음을 확인할 수 있었으며, 비선형 조석은 비대칭 조류를 생성하는 데 결정적인 역할을 하여 조류의 비대칭성인 강한 목포해역에서 조류를 모의할 때는 개방경계 조위에 비선형조석을 포함해야 함을 확인할 수 있었다.

• 대기
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• 제27권4호
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• pp.399-409
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• 2017

The impact of land cover changed by tidal flats on local meteorology in Gyeonggi Bay was quantitatively evaluated based on a numerical modeling approach during 18 days (21 June to 9 July 2013). The analysis was carried out using three sets of simulation scenarios and the land cover of tidal flats for each simulation was applied as follows: (1) the herbaceous wetland representing coastal wetlands (i.e., EXP-BASE case), (2) the barren or sparsely vegetated representing low tide (i.e., EXP-LOW case), (3) the water bodies representing high tide (i.e., EXP-HIGH case). The area of tidal flats was calculated as about $552km^2$ (the ratio of 4.7% for analysis domain). During the daytime, the change (e.g. wetlands to water) of land cover flooded by high tide indicated the decrease of temperature (average $3.3^{\circ}C$) and the increase of humidity (average 13%) and wind speed (maximum $2.9m\;s^{-1}$). The changes (e.g. wetlands to barren or sparsely vegetated) of land cover induced by low tide were smaller than those by high tide. On the other hands, the effects of changed land cover at night were not apparent both high tide and low tide. Also, during the high tide, the meteorological change in tidal flats affected the metropolitan area (about 40 km from the tidal flat).

• 한국해안해양공학회지
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• 제14권2호
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• pp.151-160
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• 2002

3차원 흐름 모델링시스템 FEMOS를 개발하고, 아산만 조류분포를 모의하였다. 개발된 시스템은 조간대 모의를 할 수 있으며, 수치해석방법으로 유한요소법을 사용하여 격자형성이 자유스러우며, 복잡한 해안선을 효과적으로 나타낼 수 있다. 넓은 조간대와 큰 조차, 얕은 수심을 가진 아산만의 조류분포 모의에 시스템을 적용한 결과, 모의결과는 장기간의 중층에서 유속변화, 층별 유속의 시간변화와 일치하는 양호한 계산결과를 보였다. 아산항 건설 전·후 조류 계산결과에 기초하여 산정한 바닥마찰응력 분포 변화를 수심변화 관측결과와 비교한 결과, 마찰음력이 증가하는 곳에서는 침식으로 수심이 깊어지고, 감소하는 곳에서는 퇴적으로 수심이 얕아지고 있음을 확인할 수 있었다. 개발된 본 모델링시스템은 그 적용성이 입증됨에 따라 복잡한 해안선과 지형을 가진 연안해역의 해수유동 연구에 널리 활용될 수 있을 것이다.

• 대한토목학회논문집
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• 제30권1B호
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• pp.33-40
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• 2010

본 연구에서는 조석으로 인한 만에서 부유사 이동과 해저지형변화 예측에 대한 2차원 유사운송모형인 HSCTM-2D 모형의 적용성을 평가하였다. 또한, 보정된 모형을 이용하여 아산만 해역과 천수만 해역에서 점착성 부유사의 유입으로 인한 장기 퇴적량을 추정하였다. HSCTM-2D 모형을 보정하기 위하여 대상해역에 위치한 검조소의 실측조위자료와 모의기간 동안 측정한 유속 및 부유사농도 자료를 모의결과와 비교하였으며, 실측자료와 모의결과가 유사한 경향을 나타내는 것으로 확인되었다. 대상해역의 퇴적환경을 고려하여 외해유입 부유사 농도를 결정하고 장기간의 조석활동에 의한 점착성 부유사의 퇴적량을 추정하였으며, 아산만 해역에서는 연간 퇴적율이 8.1 cm/yr, 천수만 해역에서는 연간 퇴적율이 14.5 cm/yr를 나타냈다. 이와같은 연구결과로부터 적용된 모델링 시스템이 해역의 점착성 부유사 이동 및 퇴적과정에 대한 이해와 완화대책수립에 유용할 것으로 판단된다.