• 제목/요약/키워드: Bottom Topography

검색결과 187건 처리시간 0.027초

Variations of Sea Level and Sea Surface Temperature in Korean Seas by Topex/Poseidon and NOAA

  • Yoon, Hong-Joo;Kang, Heung-Soon;Lee, Bong-Sic;Jeong, Young-Deok
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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    • pp.880-883
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    • 2006
  • Altimeter(Topex/Poseidon) and AVHRR(NOAA) data were used to study the variations and correlations of Sea Level(SL) and Sea Surface Temperature (SST) in the North East Asian Seas from November 1993 to May 1998. This region is influenced simultaneously to continental and oceanic climate as the border of the East Sea(Japan Sea). SL and SST have increased gradually every year because the global warming, and presented usually a strong annual variations in Kuroshio extension region with the influence of bottom topography.

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3차원 해수유동모델에 의한 제주항 연안해역의 해수순환 특성 (The Characteristics of Circulation in the Coastal Area of Jeju Harbor Using the Three Dimensional Ocean Circulation Model)

  • 양태혁;양성기
    • 한국환경과학회지
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    • 제20권6호
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    • pp.679-686
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    • 2011
  • The characteristics of circulation in the coastal area of Jeju Harbor in Korea was examined using the Princeton Ocean Model(POM) with a sigma coordinate system. The result of numerical analysis well corresponded to the observed current data. The velocity at offshore was stronger compared to coastal area during the both period of in maximum flood and maximum ebb of spring tide. According to mean wind velocity, the tidal velocity at the shallow area of Jocheon was slightly increasing during maximum ebb. The effect of wind on the circulation was stronger in shallow area and showed rapid change with depth.

동해안 이상 너울 추산에 관한 고찰 (Examinations on the Wave Hindcasting of the Abnormal Swells in the East Coast)

  • 김태림;이강호
    • 한국해양공학회지
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    • 제22권6호
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    • pp.13-19
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    • 2008
  • Abnormally large swells that appeared on the coast of the East Sea in October in 2005 and 2006 were simulated using SWAN model to examine the accuracy of the model for future forecasting Seawind data calculated based on the weather chart ant bottom topography were used for input data, and the model was operated more than 20 days before the observed swells to avoid the problems from the cold start of the model. The comparisons with observed wind and wave data were unsatisfactory and neededmore improvement in terms of swell component in the wave model as well as the quality of seawind data. The satellite wind and wave data can be good candidates for future comparison of the wave model results in the East Sea.

Mean Flow and Variability at the Upper Portion of the East Sea Proper Water in the southwestern East Sea with APEX Floats

  • Lee, Ho-Man;Kim, Tae-Hee;Kim, Ju-Ho;Youn, Yong-Hoon
    • 한국환경과학회:학술대회논문집
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    • 한국환경과학회 2003년도 International Symposium on Clean Environment
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    • pp.145-150
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    • 2003
  • 16 APEX floats, autonomous profiling floats deployed as part of the Array for Real-time Geostrophic Oceanography (ARGO) program, are used to understand the currents at 800 m underwater in the southwestern East Sea. The flow penetrates into the Ulleung basin (UB) through two paths: an extension of the southward flowing the North Korean Cold Water along the east coast of Korea and between Ulleung Island and Dok island. Flows at 800 m are observed range 0.2 to 4.29 cm/sec and the variability in the north in the DB is stronger than that in the south. The eddy kinetic energy is found a few $cm^{2}$ $S^{-2}$. In the UB, cyclonic flows from 0.3 - 1.6 cm/see are observed with the bottom topography.

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금강하구둑 건설 전${\cdot}$후의 흐름특성에 관한연구 (A Study on the Tidal Flow Characteristics of Before and After Constructed Keum River Estuary Dike)

  • 신문섭;이동주;홍성근;김재형;박성열
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2004년도 학술발표회
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    • pp.992-996
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    • 2004
  • 천해역(shallow sea area)에서의 조류 형태(tidal flow regime)는 주로 만(bay)이나 해안선(shoreline)의 형태, 해저 지형(bottom topography), 수로(channel), 천퇴(sand bar)나 간석지(tidal flat) 등의 지형적인 요인에 의해 결정된다. 본 연구는 복잡한 지형적 변화 및 천해특성에 기인된 조석(tide)의 현상이 뚜렷이 나타나는 금강하구(Keum River Estuary)를 하구둑(Estuary Dike) 건설 전${\cdot}$후(Before and After Constructed)의 수심(depth)변화 및 유속(current)변화를 수치실험(numerical experiments)으로 고찰했다.

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연식방향의 가속도를 고려한 장파의 변형해석 (Transformation of Long Waves with Vertical Acceleration)

  • 여운광
    • 한국해안해양공학회지
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    • 제2권2호
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    • pp.112-117
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    • 1990
  • 수면경사가 크거나 수심이 급격하게 변하는 지형에서는 유선의 굴곡으로 인한 연직방향의 가속도가 생겨 정수압과 다른 압력분포를 나타낸다. 따라서 이 경우 이들의 경향을 고려한 Boussinesq식을 사용해야 한다. 여러 가지 방법에 의하여 식을 얻을 수 있으나 여기서는 난류해석을 위한 평균류의 개념을 도입하여 유사한 식을 유도하였으며 기존의 식들과 비교하였다. 또한 실제 수치해석에 의하여 해를 구하고 Boussinesq항의 영향을 검토하였다.

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Wind loading characteristics of super-large cooling towers

  • Zhao, L.;Ge, Y.J.
    • Wind and Structures
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    • 제13권3호
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    • pp.257-273
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    • 2010
  • The aerodynamic and aero-elastic model tests of the China''s highest cooling tower has been carried out in the TJ-3 Boundary Layer Wind Tunnel of Tongji University. By adopting a scanivalve system, the external wind pressure is firstly measured on $12{\times}36$ taps for a single tower, two and four grouped towers under the condition of both smooth flow and the boundary layer due to surrounding geographic and building topography. The measurements of internal wind pressure distribution of $6{\times}36$ taps are taken for a single tower under the various ventilation ratios ranging from 0% to 100% of stuffing layers located at the bottom of the tower. In the last stage, the wind tunnel tests with an aero-elastic model are carefully conducted to determine wind-induced displacements at six levels (each with eight points) with laser displacement sensors. According to the measurement results of wind pressure or vibration response, the extreme aerodynamic loading values of the single or grouped towers are accordingly analyzed based on probability correlation technique.

해도를 이용한 해안 지형의 변화량 산정 (Estimation of Coastal Terrain Differences Using the Chart)

  • 양인태;한성만;최승필
    • 한국측량학회지
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    • 제20권2호
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    • pp.207-214
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    • 2002
  • 서해 연안의 개발은 갯벌의 감소로 해양생태계를 위협하고 있으며 산업화에 따른 대형 매립공사는 주변의 기상변화와 해상변화를 일으켜 해저지형 및 해안선에 많은 변화를 발생시키고 있다. 또한 선박의 안전한 입, 출항을 위한 항로에 영향을 주고 있다. 따라서 본 연구는 해도에 나타난 기준선인 최저저조면의 해양 기준면에 근거한 해안선(0 m선), 수심 2 m선. 그리고 지형도에 근거한 해안선(육지부분)으로 나누어 수치화하였으며 수치화 된 도면을 4개의 구역으로 구분하여 분석함으로써 인천국제공항 건설, 신도시 개발, 방조제 공사 등의 서해 연안 개발에 따른 해안과 해저의 변화 정도를 알아보았다.

완경사 방정식의 확장에 관한 연구 (A Study on the Extension of Mild Slope Equation)

  • 천제호;김재중
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2003년도 춘계학술대회 논문집
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    • pp.72-77
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    • 2003
  • In this study, Mild slope equation is extended to both of rapidly varying topography and nonlinear waves in a Hamiltonian formulation. It is shown that its linearzed form is the same as the modified mild-slope equation proposed by Kirby and Misra(1998) And assuming that the bottom slopes are very slowly, it is the equivalent with nonlinear mild-slope equation proposed by Isobe(]994) for the monochromatic wave. Using finite-difference method, it is solved numerically and verified, comparing with the results of some hydraulic experiments. A good agreement between them is shown.

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광각 포물형 완경사 방정식에 관한 연구 (A Study of Wide-Angle Parabolic Mild Slope Equation)

  • 김재중;박정철
    • 한국항만학회지
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    • 제12권2호
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    • pp.281-290
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    • 1998
  • The propagation of water waves over irregular bottom bathymetry and around islands involves many process-shoaling, refraction, energy dissipation and diffraction. Numerical model in this study is developed with the mild slope equation to investigate wave transformation in water of varying depth and combined waves and a current. The method used is splitting method and minimax approximation. The numerical method used in this study is Crank-Nicolson scheme in the FDM. This model is applied to Vincent shoal and compared with laboratory experimental data. The results agreed well with laboratory data. Current effect is considered in this study. This model can be used for the estimation of rip current in the slowly varying topography.

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