• 한국해양학회지
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• 제28권2호
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• pp.86-100
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• 1993

ADI(Alternating Direction Implicit) 유한차분법을 사용하여 3차원 경합 해수유 동 모델 BACHOM-3을 개발하였다. 본 모델을 장방형 내만에서 하나의 결점을 갖는 정상 파에 적용하여 해석해와 비교하였으며, 그 결과 해석해와 잘 일치하였다. 모델의 현지 적용성과 수영만의 해수유동을 조사하기 위해 모델을 수영만에 적용하여 대조기 평수 시 현지관측결과와 비교하였으며, 그 결과 현지 관측결과와 비교적 잘 일치하였다. 만 중앙부의 제 1층(수심 0∼2 m)과 제 2층(수심 2∼5 m)에서 조석잔차류는 시계방향으로 회전하는 순환류가 나타났으며, 또한 낙조류가 창조류보다 강하게 나타났다. 계산된 유속분포에 의하면, 표층과 저층 사이에 유속의 위상차가 나타나며, 표층으로 갈수록 위상의 지연이 나타났다. 그리고, 본 모델을 홍수시와 바람 효과를 고려한 흐름 장의 계산에도 적용하였다. 해양에서 육지로 바람이 불 때 표층에서는 풍향에 대응하는 유 속분포를 나타냈으나, 저층의 육지경계부근에서는 풍향과 반대방향의 흐름이 나타났 다.

• Journal of Advanced Marine Engineering and Technology
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• 제33권8호
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• pp.1275-1280
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• 2009

인공어초 시설해역 1개 정점에서 15일 연속조류를 관측하였다. 정점의 최강유속은 약 82.4 cm/sec로 나타났으며, 평균유속은 최강유속보다 대략 5.9 ~ 19.0 cm/sec 정도 작은 값을 보였다. 조시별 평균유속은 12.8 ~ 28.0 cm/sec로 나타났다. 어초군 주변 4방위에 대해 시료를 채취하여 분석한 결과, 주조류방향에 따라서 서로 다른 저질로 구성되어 있는 것을 볼 수 있었다. 이와 같은 결과로 볼 때, 인공어초 전면 및 후면에서 퇴적 및 세굴이 지속적으로 발생하기 때문에 주조류 방향에 따라서 서로 상이한 저질이 분포하는 것으로 판단된다.

• Journal of the korean society of oceanography
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• 제36권3호
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• pp.72-82
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• 2001

The progress of giant dyke construction off the Mangyung and Donajin rivers, has yielded enormous impact on the estuarine environment, both hydrodynamically and sedimentologically. Especially the inter-dyke gap in the northern Saemankeum area, 4 km wide between Yamido and Piungdo, has acted as an artificial tidal inlet. Due to such a changed geometry, tidal regime has been reversed from being flood- to ebb-dominated with a directional change from NE-SW to E-W. As a result, a large tongue-like tidal sand bar (named Saemankeum Bar) has conspicuously grown seaward through the artificial tidal inlet. The Saemankeum Bar composed of well-sorted very fine sands (3.0-3.5${\phi}$) has grown at a rate of 1.63 km/yr for the past three yews (1996-1998). Such a rapid growth of the sand bar is attributed to enhanced sediment supply derived from the degradation of former tidal sand bars at the mouth of the Mangyung River. Eventually the reworking of the tidal sand bars also caused the pre-existing tidal channels to be wider, deeper and more straightened. All of these phenomena well examplify the critical effect of artificial modifications on the natural estuarine environments.

• 한국수자원학회논문집
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• 제30권6호
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• pp.649-659
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• 1997

The influence of polluted water discharged from the Saemankeum Lake is predicted by using two-dimensional finite element model. The simulation results show that influence of the Polluted water to the northern part of the Kckunsan Islands is small during flood time. The reason is because lock gates are located in the south of the Kokunsan Islands so that tidal current directing north is blocked by these Islands. However, during the ebb time, the influence of the polluted water is extended to the whole southern part of the Kokunsan Islands. When the amount of ten percent of the total volume of polluted water is discharged from the Saemankeum Lake, equi-concentration contour line of one tenth of initial discharge concentration includes the inner area surrounded by Sinsi Island, Munyeo Island, Bian Island, and Daehang-Li. In general, peak concentration near the lock gates is found out to be higher during the spring tide than the neap tide.

• 한국해안해양공학회지
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• 제18권1호
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• pp.63-68
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• 2006

조석 주기 동안에 시간에 따라 위치가 변하는 수륙 경계선은 조간대 지형을 측정하는 보조 자료로 활용될 수 있다. 즉 밀물 시 연속적으로 촬영된 영상으로부터 추출된 수륙경계선의 표고는 해수면 변화 자료를 이용하여 등심선으로 이용할 수 있으며 등심선의 수평거리는 영상 기하보정 처리를 통하여 정량적인 값으로 변환할 수 있다. 이러한 관측 기술을 서해안의 대이작도 큰풀안 백사장에 적용하였다. 조간대에서의 자연적인 수위변화를 이용하는 영상 관측 기법은 정확도가 높으며 또한 시간과 경제적인 측면에서 유리하다. 이러한 기술은 3차원 수조에서 연안지형 변화를 연구하는 물리모형 실험에서 시간별 지형 변화를 관측하는데 효과적으로 사용될 수 있다.

• 수산해양기술연구
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• 제32권1호
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• pp.50-58
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• 1996

The authors carried out a field experiment to confirm the effect of underwater sound on the luring of fish schools in a setnet in the coast of Cheju Island. The effects of the acoustic emission on the luring of fish schools were observed using a manufectured underwater speaker in the setnet, and pure sound, of which frequency was 600Hz and the source level was 126dB, was emitted on and off at 5 minutes intervals in the set net during the night of ,July 29 and ,July 31. So we had recorded behavior of fish schools by the telesounder with two channel and shape of the setnet by underwater video camera and analyzed them. When the flood and ebb currents were around the setnet, the nets rised to the surface of water and it happened occasionaly at the stand of tide. Therefore, it was in the state that fish schools feel constraint to enter into the setnet, and was required a new design of the setnet stand up to strong tidal current. As the pure sound, of which frequency was 600Hz was emitted for the luring of fish schools in a setnet, the catch ammounts of fish, the young horce mackereWI'rachllrlls japonicus), was increased 4~6 times than not emitted.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2000년도 추계종합학술대회
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• pp.614-617
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• 2000

영광 원자력발전소 온배수의 최대영향범위를 Lagrange 방법으로 파악하기 위하여 대조기에 TGPS Buoy의 궤적 및 이에 따른 표층수온의 측정을 년 4회 실시하였다. TGPS Bouy의 추적결과, 온배수는 낙조시 남서.서남서방향으로 플릅의 형태로 배수구로부터 약 12km 정도를 이동하며, 낙조류가 우세한 이 해역의 특성으로 3-4회에 걸친 거듭된 낙조류에 따라 칠산도까지 도달할 수 있었다. 그리고 온배수는 배수구로부터 춘.추계에 약 5km, 하계는 약 10km 떨어진 지점에서 수온급강하가 나타나고, 동계에는 차가운 대기에 의하여 지속적인 Cooling이 발생하는 것으로 나타났다.

• 한국수산과학회지
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• 제28권5호
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• pp.607-623
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• 1995

A numerical model of hydraulic resistance by hanging aquaculture facilities is developed and applied to a model basin and a field. A drag stress term formulated by the quadratic law of drag force is introduced Tn the equations of motion for a two-dimensional depth-averaged flow. In the model basin, numerical experiments ave tarried out for the various shape of obstructions, string density and layout of facilities etc.. The flow pattern around the facilities is affected sensitively by the density of string and the layout of facilities. On the other hand, the velocity decay due to the hanging oyster aquaculture facilities is observed in Kamak bay, where the maximum velcocity decay rate is $25\%$ in spring tide. The model is also applied to the field, Kamak bay. The velocity decay rate in the model is comparable with the field measurement data. The velocity decreases around the down-stream area of the facilities, .hut it increases in the other region. The water elevation decreases during the flood and it increases during the ebb.

• 한국환경과학회지
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• 제18권11호
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• pp.1299-1307
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• 2009

In order to measure in-situ suspended particle size, volume concentration of suspended particulate matter and current speed, mooring observation was performed at the Gwangyang Bay by using of an optical instrument, 'LISST-100' and an acoustic instrument, 'ADV'(St. S1). And the sediment flux was obtained based on the concentration of suspended particulate matter and current speeds measured at three lines of Gwangyang Bay during ebb and flood tide of August 2006. To investigate the spatial variation of suspended particulate matter, profiling observations were measured difference echo intensity and beam attenuation coefficient by using of ADCP and Transmissometer (Line A, B, C). The suspended sediment flux rate at the mouth of Gwangyang Bay was observed to be higher during asymmetrical than symmetrical of current speeds. The flux of suspended particulate matter concentration and current speeds were transported to southeastern direction of surface layer and northwestern direction of bottom layer at the western area at line A of Gwangyang Bay. Small suspended particles have been found to increase attenuation and transmission more efficiently than similar large particles using acoustic intensity (ADV/ADCP) or optical transmit coefficient (LISST-100/Transmissometer). The application and problems as using optical or acoustic instruments will be detected for use in time varying calibrations to account for non-negligible changes in complex environments in situ particle dynamics are poorly understood.

• 수산해양기술연구
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• 제28권2호
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• pp.117-131
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• 1992

A studies on the pattern of sea water circulation was carried out by using drogue experiments, tidal current measurement and hydrographic data in Kamak Bay which has two channels. At the flood, the water inflowed from the northern narrow channel flows mostly to the southward then the westward because Daekyung-island located at the flow path, at the same time the water from the southern channel of bay directed strongly to the north with a spine centered at around Gunnaeri. And these waters converged at the area between eng-Island and Deakyung-Island in the bigining of the flow, and placed at less southern part than the area at the late. The water of the north west inner bay having concave bottom topography inflows to Najin inlet with a spin of anti-clockwise. At the ebb, those waters in the bay turn back to two channels respectively, but most of waters directed to the southern channel of the bay. The directions of residual current of two channels are the southward mainly, and the current of inner area are influenced by the prevailing wind. The north-west inner bay which has the weak tidal current less than 10 cm/sec shows a similar upwelling by off-shore wind in winter, and the stratification in summer, respectively.