• 한국지구과학회지
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• 제30권2호
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• pp.247-256
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• 2009

함평만 해역에서 CTD, 조류 및 조석 자료를 이용하여 해수의 물성구조 및 조류 특성을 파악하였다. 이 지역 대기의 계절적 변화에 따라 수온, 염분은 여름철에 고온, 저염의 저밀도 상태를 나타내었으며, 겨울철에 저온, 고염의 고밀도 상태를 보였다. 특히, 여름철 소조기에 중심수로를 따라 조석전선과 유사한 수온 구조가 형성되었으며, 조석전선 위치를 나타내는 $SH(=log_{10}(H/U^3)$, 여기서 H는 수심, U는 $M_2$조류진폭)값은 2.4-3.5로 평가되었다. 또한 성층계수$({\phi})$는 0.985-6.998 Joule/$m^3$으로 내만으로 갈수록 점차적으로 증가하였다. 이러한 전선구조 발생은 함평만 내부의 넓은 갯벌을 포함하는 독특한 지형학적 특성과 조류 세기의 지역적 변화에 의해 발생되는 것으로 여겨진다. 함평만 입구에서 관측된 조류는 수심이 증가할수록 창조시간 보다 낙조시간이 짧았다. 이러한 조류의 비대칭적인 낙조우세현상은 넓은 대조차 조간대가 분포하고 있는 함평만에서 천해조의 발달로 인한 조석 왜곡 현상 결과로 해석되어진다.

• 생태와환경
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• 제46권1호
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• pp.41-52
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• 2013

To decide on the designation of a tidal-flat Provincial Park, a study area was defined in line with domestic and international case studies of Provincial Parks. A survey on landscape, geology, biota, and cultural resources was conducted in four tidal-flat areas including Bigeum-myeon and Docho-myeon, which are part of the UNESCO Biosphere Reserve in Shinan, Jeollanam-do. To identify areas most suitable to be designated as Provincial Park, a PSR evaluation process was adopted. This has resulted in the selection of the 'Palgupo' area surrounding Bigeum, Docho, Haui, Shinui, Jaeun, Amtae, Palgeum, Anjwa and Jangsan. Also the tidal-flat areas at Aphae-myeon, which are ecologically linked with the Jeungdo Tidal-flat Provincial Park, were included. The selected areas resulting from this study will meet various characteristics of tidal-flat ecosystems including naturalness, ecological network, rarity and eco-cultural diversity. After the tidal-flat Provincial Park has been specified, there is a need to perform a long-term sustainable management plan.

• 수산해양기술연구
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• 제57권3호
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• pp.214-227
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• 2021

The distribution of tidal current and tidal induced residual current, topographical eddies and tidal residual circulation in the waters surrounding the Geumo Island-An Island channel were identified through numerical model experiments and vorticity balance analysis. Tidal current flows southwest at flood and northeast at ebb along the channel. The maximum flow velocity was about 100-150 cm/s in neap and spring tide. During the flood current in the neap tide, clockwise small eddies were formed in the waters west of Sobu Island and southwest of Daebu Island, and a more grown eddy was formed in the southern waters of Geumo Island in the spring tide. A small eddy that existed in the western waters of Chosam Island during the ebb in neap tide appeared to be a more grown topographical eddy in the northeastern waters of Chosam Island in spring tide. Tidal ellipses were generally reciprocating and were almost straight in the channel. These topographical eddies are made of vorticity caused by coastal friction when tidal flow passes through the channel. They gradually grow in size as they are transported and accumulated at the end of the channel. When the current becomes stronger, the topographic eddies move, settle, spread to the outer sea and grow as a counterclockwise or clockwise tidal residual circulation depending on the surrounding terrain. In the waters surrounding the channel, there were counterclockwise small tidal residual circulations in the central part of the channel, clockwise from the northeast end of the channel to northwest inner bay of An Island, and clockwise and counterclockwise between Daebu Island and An Island. The circulation flow rate was up to 20-30 cm/s. In the future, it is necessary to conduct an experimental study to understand the growth process of the tidal residual circulation in more detail due to the convergence and divergence of seawater around the channel.

• 한국패류학회지
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• 제30권2호
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• pp.117-126
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• 2014

바지락 양식장의 해수 수온은 황도가 정산포에 비하여 높은 것으로 나타났지만 염분은 황도가 낮았으며 용존산소와 pH는 비슷한 값을 나타났다. 그리고 엽록소 a 와 규산염은 황도가 높았으며 무기질소와 무기인은 비슷한 농도로 나타났다. 퇴적물의 입도는 황도가 세립질이고 분급이 양호하며, 정산포는 조립질이고 분급이 불량하였고, 유기물은 황도에서 높게 나타났다. C/N 비는 황도와 정산포에서 10 이하의 값을 나타내어 외부에 의한 오염보다는 해양기원의 유기물에 의한 것으로 조사되었으며 C/S 비는 두 지역에서 2.8 이하로 정상적인 해양환경으로 조사되었다. 중금속에 대한 농축비 (Ef) 는 두 지역에서 1 보다 크게 나타나 중금속이 유입 또는 금속황화물 형성과 관련된 축적현상으로 퇴적물에 농축되어 있음을 의미한다. 또한 농집지수 (Igeo)의 결과는 연구지역이 Igeo class가 1에 집중되어 있어 약간 오염되었거나 오염되지 않은 수준 (practically unpolluted / moderately polluted) 으로 나타났다. 조석에 따른 1차 생산력에서 황도가 정산포에 비하여 높게 나타났으며, 황도에서는 2월과 8월에 높고 5월에 낮은 반면 정산포에서는 8월만 높게 나타났다. 생산성 평가를 위하여 채집한 바지락의 비만도는 황도가 높았지만 크기와 서식밀도는 정산포가 크게 나타났다. 서식밀도의 변화에 대한 조사결과를 보면 7월까지 어획, 8월부터 종패의 가입 그리고 9월에는 폐사 때문인 것으로 사료된다.

• 유기물자원화
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• 제8권2호
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• pp.85-92
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• 2000

자연간석지 토양을 인공간석지에 인공간석지 토양을 자연간석지에 이식하고, 이식토양의 물리화학적 및 생물학적 특성의 변화를 추적하였다. 또한 실트함량과 유기물함량이 미생물현존량에 미치는 영향에 관해서 실내실험을 통하여 검토하였다. 자연간석지 토양을 인공간석지에 인공간석지 토양을 자연간석지에 이식한 결과, 실트함량, 유기물함량, 미생물현존량 및 토양중의 산화환원전위층은 시간의 경과와 함께 이식한 간석지의 토양구조와 동일하게 변이해 가는 것을 알았다. 또한 이식 토양중의 실트함량, 미생물현존량 및 유기물함량과는 높은 상관관계를 나타내었다. 실트함량 및 유기물함량의 증감과 함께 미생물현존량이 비례해서 증감하는 것을 알았다. 또한 실내실험 결과에서도 실트함량이나 유기물함량의 증가와 함께 미생물현존량이 증가하였다. 또한 그 원인은 실트함량이 증가함에 따른 결과라는 것을 알 수 있었다.

• Ocean and Polar Research
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• 제27권4호
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• pp.433-441
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• 2005

To investigate the characteristics of tidal currents and water circulation in the coastal waters off the Taean Peninsula, tidal currents and sea levels were measured at the study area from 1998 to 2004. In the central waterway to the south of Changan Sand Ridge, mean speed of tidal currents and residual currents were 74.0cm/s, 17.8cm/s respectively; the dominant residual currents flowed northeastward, and the amplitudes of semi-diurnal components $(M_2,\;S_2)$ were larger than diurnal components $(O_1,\;K_1)$. The flood and ebb tidal currents were northeastward and southwestward, respectively, and each period was about 6 hours for them, which was consistent with the period of sea levels at the study area. In the coastal region near Hakampo, Taean, mean velocities of tidal currents and residual currents were 46.1cm/s, 30.8cm/s respectively, and the dominant residual currents flowed southwestward. The amplitudes of shallow water constituents $(M_4,\;MS_4)$ were relatively laige, which were weaker to the northeastern coastal region off Mineodo. The northeastward flow continued for about $2{\sim}3$ hours, while the southwestward flow continued for about $9{\sim}10$ hours near Hakampo during the tidal period. Tidal currents flowed northeastward in the central area of the waterway during the period from the Low Water Level (LWL) to the High Water Level (HWL). While the currents in the coastal region flowed northeastward for the first 3 hours after the LWL, southwestward counter-currents flowed between 3 and 6 hours after the LWL. During the period from the HWL to the LWL, the dominant currents flowed southwestward in the study area except to the northeastern coastal region off Mineodo. Along the shorelines, the counter-currents flowed northward between 4 and 6 hours after the HWL. It seems that the counter-currents near the coastal region are caused by the topography and the geography of the shorelines at the study area.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2001년도 춘계학술대회 논문집
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• pp.154-159
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• 2001

Nakdong estuary is located at south-eastern coast of the Korea. A lot of sediment from upper river was deposited at this area. It has caused many problems such as changes in topography and tidal current. In this paper, field observation data on tidal currents and sediments were investigated as well as historical topographic changes by dredging and reclamation of the foreshore. Then, the numerical model considered the settling velocity of the suspended solids according to the particle size was applied to examine the characteristic of deposition. The results are as follows : 1. Changes of characteristics of deposition were caused by topographic changes of Nakdong estuary 2. Characteristics of deposition were influenced by river plume and tidal currents. 3. Numerical model which considers settling velocity reappeared distribution of deposition by particle-size. 4. Used model is only resonable for discussion in the quality, so, it is strongly suggested that the new model development is needed including the quatitative deposition processes.

• 수산해양기술연구
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• 제50권4호
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• pp.435-446
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• 2014

Tidal turbulence was examined using three-dimensional tidal velocity data observed at a trench offshore of Tongyoung, Korea. The kinetic energy and intensity, including the variation period of the flow velocity and direction, were used to investigate the relationships between tidal turbulence and fishing gear dynamics, including the effects of swimming fish during fishing operations. As the resultant velocity increased from 0.2 to 0.9 m/s, the kinetic energy also significantly increased, while the turbulence intensity decreased from 50 to 10%. Tidal flow in strong flow fields displayed shorter periods of between 4 and 10 s, as determined by fast Fourier transform, the global wavelet method, and peak event analysis, and the periods were compared with the period of response to swimming fish and to oscillation of fishing gear. As mean velocity increased, velocity amplitude also increased from 0.1 to 0.6 m/s, and its directional amplitude changed markedly from 20 and $90^{\circ}$. Our study suggests that tidal turbulence can influence fish behavior or fishing gear geometry during fishing operations, although our analysis considered only a limited area. In future work, observations should be carried out over a more extensive depth and area.

• 전기학회논문지
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• 제61권6호
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• pp.791-796
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• 2012

This paper presents the various analysis of the power system for operating the new SIHWA tidal power plant. In the analysis of the power system, summer load condition of 2011 is used. Especially, power flow, fault current, voltage and contingency of SIHWA tidal power plant area are analyzed by using PSS/E and there is no problem for the dynamic stability simulation. The new SIHWA tidal power plant is located in near metropolitan area where about 43% amount of the system load is consumed. Therefore, transmission losses are reduced. In addition, system marginal price can be lowered by generating the new SIHWA tidal power plant. The generation pattern of the SIHWA tidal plant is analyzed and the changes of generation are presented for various water levels by control of the rotor angle alpha and beta in water wheel generator.

• Ocean Science Journal
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• 제42권2호
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• pp.69-79
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• 2007

A vertical transect with 4 km length was established for the macrofaunal survey on the Chokchon macrotidal flat in Kyeonggi Bay, Incheon, Korea, 1994. Tidal elevation (m) and sediment mean grain size $(\phi)$ were inversely predicted by the transfer functions from the faunal assemblages. Three methods: weighted average using optimum value (WA), tolerance weighted version of the weighted average (WAT) and maximum likelihood calibration (MLC) were employed. Estimates of tidal elevation and mean grain size obtained by using the three different methods showed positively corresponding trends with the observations. The estimates of MLC were found to have the minimum value of sum of squares due to errors (SSE). When applied to the previous data $(1990\sim1992)$, each of three inference models exhibited high predictive power. This result implied there are visible relationships between species composition and faunas' critical environmental factors. Although a potential significance of the two major abiotic factors was re-affirmed, a weak tendency of biological interaction was detected from faunal distribution patterns across the flat. In comparison to the spatial and temporal patterns of the estimates, it was suggested that sediment characteristics were the primary factors regulating the distribution of macrofaunal assemblages, rather than tidal elevation, and the species composition may be sensitively determined by minute changes in substratum properties on a tidal flat.