• 한국해양학회지:바다
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• 제14권1호
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• pp.10-21
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• 2009

하구언과 방조제 건설에 따라 고극조위 상승과 같은 조석환경 변화가 심한 무안만에서 표층퇴적물의 분포 변화와 변화 원인을 규명하기 위하여 퇴적물 시료를 채취하고 조류관측을 실시하였다. 무안만의 표층퇴적물은 1998년에 비해 역과 사의 조립질퇴적물의 함량이 증가하고 실트의 함량이 감소하여 퇴적물의 평균입도는 6.2${\phi}$에서 5.8${\phi}$로 조립해지는 경향을 보였다. 조립질퇴적물의 함량 증가와 실트의 함량 감소는 만조선 주변을 중심으로 광범위하게 나타났으며, 특히 동암리와 구로리, 압해도 조간대에서 두드러지게 나타났다. 만조선 주변의 조립화 현상은 일차적으로 하구언 및 방조제 건설에 따른 고극조위 상승에 기인하는 것으로 해석된다. 한편, 서측 만입구 주변에서 세립질퇴적물의 함량이 증가하는 현상은 인공구조물(교각) 건설에 따른 조류속의 감소와 위상차에 의한 조류의 방향 변화 등 수류의 변형에 기인하는 것으로 판단된다.

• 한국지역지리학회지
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• 제12권3호
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• pp.339-351
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• 2006

뻘중심의 갯벌이 넓게 형성된 가로림만의 웅도리외 모래 갯벌과 염전이 발달한 영광 갯벌의 두우리, 수산 양식업이 발달한 곰소만 주변 지역을 대상으로 조석 주기, 갯벌 지형. 갯벌 퇴적물의 입도 특성과 주민 생활과의 관련성을 검토했다. 갯벌 주변 주민들에게 갯일은 농사일보다 우선되고, 갯벌에서 얻어지는 수입이 이들의 주소득원이다. 갯벌주변의 주민 생활은 조석 주기에 맞추어 이루어지고 있으며, 한사리 저조위 때는 가장 바쁘고 많은 소득을 올릴 수 있어 마치 장날과 같다. 뻘 갯벌에서는 패류 양식이 주이고, 모래 갯벌에는 안강망 어업이 활발하며, 해안에 접한 혼합 갯벌에는 염전이 발달한다. 또한 하나의 갯벌에도 경제 활동의 분화가 이루어져 조상대에는 염전과 양어장으로, 조간대에는 패류 양식장으로, 조하대는 굴, 김 양식징으로 이용된다.

• 한국해양환경ㆍ에너지학회지
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• 제13권4호
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• pp.234-240
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• 2010

연안개발로 인해 발생하는 해양환경 변화를 정확히 예측하여 해양환경을 효율적으로 관리하기 위해서는 정확한 조위 및 조류 분포에 관한 자료의 확보가 필수적이다. 그러나 현재 대부분의 환경영향평가에서는 조석 수치모의에서 제한된 조석분조 만을 사용하여 조위와 조류분포를 예측하여 많은 분조의 합성에 의해 발생되는 실제 조석현상을 정확하게 계산하지 못하고 있으며, 이로 인해 환경영향평가에 오류가 발생하고 있다. 본 연구에서는 제한된 분조의외해 개방경계에서 조화상수를 가지고도 연안에서 관측된 조위자료를 활용하여 실시간으로 정확하게 조위 및 조류 분포를 예측할 수 있는 방법을 제안하였다. 4개 분조에 의한 조위와 38개 분조에 의한 조차의 비 그리고 모의조차와 관측조차의 비를 가지고 보정한 조위 예측결과는 관측조위와 잘 일치하였다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제16권5호
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• pp.24-30
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• 2011

Tidal flats which are ecologically sensitive, are hard to remediate once they are contaminated by oil spill accidents. Traditional oil remediation measures focus on removal efficiency, and their improper implementation can adversely affect crude oil contaminated coastal areas and greatly disrupt the structure and functions of crude oil contaminated tidal flats. In this study, the oil degradation due to the implementation of remediation measures naturally enhanced using air and natural oil sorbents was evaluated in the lower strata of tidal flats. The effects of air and natural oil sorbents on oil degradation for two concentration levels (< 500 ppm and > 500 ppm) were tested at artificially contaminated tidal flats. Fifty days after these treatments, the natural oil sorbent treatment showed the lowest total petroleum hydrocarbon (TPH) concentration ($4.46{\pm}1.47%$) at the low concentration level, whereas both air and natural oil sorbent treatments showed high degradation efficiencies at the high concentration level ($29.30{\pm}4.39%$). Although the phosphatase activity decreased for all treatments, there was no significant difference between the decreases for the different treatments; on the other hand, B-glucosidase activities were high for both air and natural oil sorbent treatments. Although degradation efficiencies decreased as the concentration increased, the air provision and natural oil sorbent treatment could be an effective ecological restoration measure for oil contaminated tidal flats while minimizing the environmental impact of the remediation efforts.

• 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.

• 물과 미래
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• 제27권4호
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• pp.115-121
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• 1994

감조하천의 수위는 조석파와 상류의 유출량과의 상호작용에 의해 변화하며, 특히 만조상태에서는 홍수위가 증가하여 재해의 원인이 된다. 이러한 감조하천에서 수위는 유량만의 함수라기 보다는 유량과 조석파의 결합에 의한 함수이다. 본 논문은 조위와 하천 유량사이의 관게를 정식화하여 감조하천에서의 수위를 예측할 수 있도록 하는 것이다. 제시된 이론의 검증은 섬진강의 감조하천내에 있는 송정 및 하동수위표에 적용하였다. 적용 결과, 송정수위표에서는 수위에 대한 조위의 상관관계가 0.016으로 조위의 영향이 작으나, 하동 수위표에서는 0.558로 조위의 영향이 크게 나타났다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2003년도 The Fifth Asian Computational Fluid Dynamics Conference
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• pp.221-223
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• 2003

The tidal bores of the Qiantang River on the East coast of China are simulated numerically based on the shallow water theory. The governing equations, which were traditionally formulated using water depth, are formulated in terms of water surface level, and the fractional-step method is applied in conjunction with a Godunov-type scheme. In addition, the source terms due to bottom gradient are discretized centrally to exactly balance the flux terms. Our numerical simulation produces tidal bores in excellent agreement with field measurements.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.613-616
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• 2007

The main structures that comprise a tidal power plant are turbine structure, sluice structure, tide embankment and gate. Since these structures are founded on seabed ground, an extensive geotechnical site investigation to evaluate the engineering properties of field soils must be conducted prior to design and construction. According to the results of geotechnical site investigation conducted at the planned site for construction of Incheon bay tidal power plant, soft ground generally lie 7 meters below the seabed surface level. This research suggests the reliable and economical design of foundations and ground improvements required for construction of main structures in Incheon bay tidal power plant, with considerations on field conditions.

• Ocean Science Journal
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• 제40권4호
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• pp.221-227
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• 2005

The architecture of macrofaunal burrows and the total area of the sediment-water interface created by biogenic structure were investigated in the Donggeomdo tidal flat on the west coast of Korea. Resin casting methods were applied to recover burrows of four dominant species, Macrophthalmus japonicus, Cleistostoma dilatatum, Perinereis aibuhitensis, and Periserrula leucophryna, and whole burrows within the casting area at three sites in different tidal levels. P. leucophryna excavated the largest burrow in terms of a surface area among them. In the case of whole burrow casting, the space occupied by the biogenic structure was extended into deeper and expanded more greatly at the higher tidal level. In the uppermost flat, the burrow wall surface area within sediment was more extensive than the sediment surface area. Increased oxygen supply through the extended interface could enhance the degradation rates of organic carbon and also change the pathways of degradation. Quantifying the relationship between the extended interface and mineralization rate and pathway requires more extensive study.

• Ocean and Polar Research
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• 제33권3호
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• pp.309-319
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• 2011

This is a preliminary study of the feasibility of obtaining reliable tidal current harmonic constants, using one month of current observations, to verify the accuracy of a tidal model. An inference method is commonly used to separate out the tidal harmonic constituents when the available data spans less than a synodic period. In contrast to tidal constituents, studies of the separation of tidal-current harmonics are rare, basically due to a dearth of the long-term observation data needed for such experiments. We conducted concurrent and monthly harmonic analyses for tidal current velocities and heights, using 2 years (2006 and 2007) of current and sea-level records obtained from the Tidal Current Signal Station located in the narrow waterway in front of Incheon Lock, Korea. Firstly, the l-year harmonic analyses showed that, with the exception of $M_2$ and $S_2$ semidiurnal constituents, the major constituents were different for the tidal currents and heights. $K_1$, for instance, was found to be the 4th major tidal constituent but not an important tidal current constituent. Secondly, we examined monthly variation in the amplitudes and phase-lags of the $S_2$ and $K_1$ current-velocity and tide constituents over a 23-month period. The resultant patterns of variation in the amplitudes and phase-lags of the $S_2$ tidal currents and tides were similar, exhibiting a sine curve form with a 6-month period. Similarly, variation in the $K_1$ tidal constant and tidal current-velocity phase lags showed a sine curve pattern with a 6-month period. However, that of the $K_1$ tidal current-velocity amplitude showed a somewhat irregular sine curve pattern. Lastly, we investigated and tested the inference methods available for separating the $K_2$ and $S_2$ current-velocity constituents via monthly harmonic analysis. We compared the effects of reduction in monthly variability in tidal harmonic constants of the $S_2$ current-velocity constituent using three different inference methods and that of Schureman (1976). Specifically, to separate out the two constituents ($S_2$ and $K_2$), we used three different inference parameter (i.e. amplitude ratio and phase-lag diggerence) values derived from the 1-year harmonic analyses of current-velocities and tidal heights at (near) the short-term observation station and from tidal potential (TP), together with Schureman's (1976) inference (SI). Results from these four different methods reveal that TP and SI are satisfactorily applicable where results of long-term harmonic analysis are not available. We also discussed how to further reduce the monthly variability in $S_2$ tidal current-velocity constants.