• 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.

• 한국농공학회지
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• 제43권4호
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• pp.37-49
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• 2001

This study was performed in order to produce the basic data for developing prediction techniques of desalinization to be applicable to reclaimed tidal lands at the beginning stage. the desalinization experiments were carried out by two water management practices, namely, the leaching method by subsurface drainage and the rinsing method by surface drainage. The 5 soil samples used in this study were collected in 4 tidal land reclamation projects. Regression equations were obtained in order to investigate the changes of electrical conductivity during the desalinization of reclaimed tidal lands and to estimate water requirements for desalinization. The results obtained from this study were summarized as follows: 1. According to USDA Salinity Laboratory classification system of salt affected soils the reclaimed tidal land soils used in this study were saline-sodic soils with the high electrical conductivity and the high exchangeable sodium percentage. 2. With the increase of the water requirements for desalinization the electrical conductivity was decreased with high degree of correlationships and the desalinization effects were remakable in both the leaching method and the rinsing method. 3. In case of the leaching method the electrical conductivity had been reduced below the classification value of salt affected soils when the depth o water leached per unit depth of soil (Dwl/Ds) was 0.3 and the desalinization effects showed a tendency to be much the same in each treatment.

• 한국관개배수논문집
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• 제4권2호
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• pp.38-47
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• 1997

In the final stage of seadike closing, the flow in the tidal gap changes rapidly to high accelerating flow, causing losses of construction materials. As the tidal velocity through the gap of an end dump contraction is highly nonuniform, flow equations on

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 추계학술대회 초록집
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• pp.159.2-159.2
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• 2011

Hyundai Heavy Industries has developed a tidal current energy converter utilizing the accumulated technology as the world largest constructor for ship and offshore structures. The model has two sets of turbines in both ends in order to utilize the bi-directional current flows in flood and ebb tide. The torque produced by turbine in tidal current is directly delivered to generator along the horizontal axis, in which the turbine, gear, generator, gear and turbine are connected successively. The manufactured model for field test has the turbine diameter of 5 meters to produce the maximum power of 500kW at maximum current speed of 5m/s. The technical verification of tidal power converter was performed by means of small scale model test in towing tank as well as field test at the Strait of Uldolmok located in Jindo of Jeollanamdo province. Field test was performed by mounting the tidal current converter on the SEP(Self Elevating Platform) which could lower the 4 vertical legs on the seabed and could elevate platform over the water surface using the hydraulic power for itself. The field test performed for a month shows that power output is similar or larger compared with the expected one in design stage. This paper presents the development of tidal current energy converter and real sea field test by Hyundai Heavy Industries. This project has finished successfully and provided the technical advance toward commercial services for tidal current power generation in the south-west region in Korea.

• Ocean and Polar Research
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• 제30권4호
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• pp.497-507
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• 2008

With the reduction of tidal currents by the closing of the Saemangeun 4th dyke, sedimentary environments on the Gunsan tidal flat, the nearest inner flat from the 4th dyke, has been severely changed, which might affect macrobenthic assemblages on the habitats. In order to investigate changes in macrobenthic community structure on Gunsan tidal flat, field surveys were seasonally conducted at seven stations from April 2002 to November, 2005. Sedimentary facies on the study area were shifted into muddominant facies. The fine sediment has been greatly deposited on the tidal flat with accumulation of organic materials after closing the water passage of 4th dyke section. These drastic variations in environments gave rise to change in macrobenthic community structure. Since the closure of the 4th dyke, the number of species of macrobenthos has gradually decreased. And the filter feeders and sand-favored species such as Urothoe convexa, Macrophthalmus dilatatus, Umbonium thomasi, and Mactra veneriformis have been replaced by the deposit feeders such as Macrophthalmus japonicus and Ilyoplax pingi. MDS ordination based on Bray-Curtis similarity from forth-root transformed species abundance data showed that the macrobenthic communities have passed through three succession stages from 2002 to 2005. During the third stage of 2005 opportunistic species such as Prionospio japonica, Heteromastus filiformis and Sinocorophium sinensis increased in population on the tidal flat.

• 한국수자원학회논문집
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• 제40권10호
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• pp.793-800
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• 2007

본 연구는 조석의 영향을 받는 하동2 지점의 수위자료로부터 시간과 주파수 영역에서 유연한 분해능을 갖는 웨이블렛 변환을 적용하여 강우에 의한 유출성분과 조석에 의한 조위성분을 추출하였다. 최종파형 분해단계의 근사성분은 가장 큰 에너지 값은 87.77%를 나타내었으며, 상세성분 중 반일주조형의 주기성(약 12시간)을 갖는 D3의 에너지 값은 10.70%로 나타났다. 또한 D3의 왜도 및 첨도 값은 여수 조위자료와 유사함을 보여주었다. 따라서 하동2 지점의 수위자료에 대하여 최종 분해된 최종파형 분해단계의 근사성분(A6)과 D6, D5 상세성분은 유출성분이며, 상세성분 D4, D3, D2는 조석의 영향으로 수위가 상승과 하강을 반복하는 조위성분인 것으로 나타났다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.331-335
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• 2004

This study is focused to analyze the movement of thermal effluent dischargeed from nuclear power plant by season, ebb and flow, and before and after foundation of tide embankment using thermal infrared band image of 28 scenes observed from Landsat from 1987 to 2004, which is the early stage of operation of young-kwang nuclear power plant. In diffusion of thermal effluent discharge by seasons, spring and summer is spreading further than autumn and winter. It is considered to distribute widely mixed with thermal effluent discharge and hot water, which is distributed naturally along the seaside. It is known the fact that tidal currents control the direction of diffusion of thermal effluent discharge by the change of ebb and flow. Namely, it is distributed widely on the Southwest direction along the seaside by tidal currents when ebb and, it is moved widely on the Northeast direction along the seaside by tidal current when flood. However, in the early stage of flood current, the mainstream of thermal effluent discharge is spread on Southwest direction and, the direction is changed on North­east way when the latter period of flood current. Similarly, in the early stage of ebb current, the mainstream of thermal effluent discharge is spread on Northeast direction and, the direction is changed on Southwest direction when the latter period of ebb current. As the result of comparing to the diffusion pattern of thermal effluent discharge before and after the foundation of seawall, discharged thermal effluent from the drain of plant by the foundation of dike is shown as curved circle pattern on Northeast to West direction from the ending portion of the seawall.

• 한국지구과학회지
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• 제33권3호
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• pp.242-258
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• 2012

황해 경기만은 제4기에 반복된 해침과 해퇴로 4개의 해침-해퇴 퇴적체(DS-1, DS-2, DS-3, DS-4)를 형성하였다. 본 연구는 황해 경기만 퇴적체의 형성을 6개 퇴적단계로 나누어 설명한다. A 단계는 MIS-6 저해수면 시기로서 큰 규모의 해수면 하강으로 인해 대부분의 지역이 대기에 노출되고 광범위한 하도 침식 및 풍화작용의 영향을 받았다. 이어지는 B 단계는 MIS-5e 까지 빠른 해수면 상승과정에서 MIS-5 시퀀스의 하부 해침퇴적체가 형성되었고, 다음에 이어지는 MIS-5d부터 MIS-4 저해수면 시기까지의 C 단계에서는 MIS-5 시퀀스의 상부인 해퇴퇴적체가 만들어졌다. 다음의 D 단계는 MIS-4 저해수면 시기부터 MIS-3c 고해수면 시기까지로 하도 침식 및 하도 충전 구조로 이루어진 MIS-3 해침 퇴적체가 형성되었다. 다음의 E 단계에서는 LGM 시기까지 계속적인 해수면 하강이 있었고 외해쪽에서는 천해 기원의 MIS-3 해퇴퇴적체가 만들어진 반면에, 내륙쪽에서는 노출된 환경에서 하도 충전 퇴적체나 범람원 퇴적체가 형성되었다. 마지막 단계인 F 단계는 황해 전체적으로 홀로세 해침이 발생하였고, 이 시기에 외해쪽에서는 대륙붕 사질 퇴적체와 조석사주 퇴적체가 형성되어 고해수면 시기인 현재까지 퇴적이 일어나고 있다.

• 한국환경생태학회지
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• 제35권2호
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• pp.98-105
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• 2021

번식지에서 이소하여 분산한 유조의 이동 패턴과 서식지를 파악하는 것은 개체 보전과 관리를 위해 매우 중요하다. 노랑부리백로는 국제적인 보호종으로 필리핀, 말레이시아, 대만 등지에서 월동하며, 중국, 러시아, 우리나라 서해 무인도서에서 번식한다. 본 연구에서는 2018년도와 2019년도에 영광 칠산도에서 번식하여 이소한 노랑부리백로 유조 총 6개체를 대상으로 야생동물위치추적장치를 부착하여 이소 후 하절기 동안 이동 경로 및 행동권 분석을 통해 주요 서식지 이용 양상을 파악하였다. 2018년도에 번식한 노랑부리백로 유조 3개체 중 CE1801 개체는 이소 후 북상을 하다가 다시 영광 백수 갯벌 지역으로 회귀하여 서식하였으며, 나머지 CE1802, CE1803 개체는 태안 지역으로 북상하여 서식하였다. 2019년도의 경우 CE1901 개체는 CE1801 개체와 유사한 패턴을 보였으며, CE1902 개체는 완도 지역으로 남하하여 서식하였고, CE1903 개체는 신안 지역으로 남하하다가 다시 영광 백수 갯벌 지역으로 회귀하여 핵심 행동권을 보였다. 본 연구에서 노랑부리백로 유조는 하절기 동안 안정적인 서식지를 찾기 위해 서해안 갯벌 지역을 중심으로 폭 넓게 이동을 하였다. 향후 노랑부리백로 유조가 이용하는 핵심 서식지에 대해 개발과 출입을 제한하는 등 서식지 보호를 위한 노력이 필요하다.

• 한국환경과학회지
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• 제15권3호
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• pp.243-252
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• 2006

The emergy concept was used to valuate the contributions of a tidal flat ecosystem included in the fourth stage reclamation plan for the Youngsan River area to the Korean economy. Emergy contributions of the ecosystem were compared with those of economic valuations performed on the same ecosystem. The tidal flat ecosystem contributed 3.55 million EmW/ha annually. This, however, cannot be compared directly with those of the economic valuations because both methodologies approach the valuation of ecosystems in different perspectives. The emergy methodology is a donor-based valuation in which what goes into making a product or service is measured, while the economic valuation is a receiver-based approach in which human receivers determine the value of an ecosystem product or service. An emergy valuation was conducted for the three ecosystem functions included in the economic valuations to compare the results of both methodologies on the same basis. Fishery production and pollutants removal contributed 9.86 million EmW/ha/yr and 0.88 million EmW/ha/yr, respective1y. The conservation value of the tidal flat ecosystem was 3.55 million EmW/ha/yr. Overall, the emergy valuation that try to include works of both human and nature on the same basis resulted in higher economic contribution of the tidal flat ecosystem than that calculated by the economic methodologies in which only human works are measured based on the willingness-to-pay of people. This study showed that the emergy concept could provide an alternative tool for policy decision-making regarding utilization and conservation of ecosystems by approaching the ecosystem valuation from a different perspective than that of economic methodologies.