• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2003.08a
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• pp.216-221
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• 2003

황천 시에 쇄파대 내에서 발달한 장주기파는 전빈의 침식에 직집적인 원인이 되는(가여 1992) 등, 쇄파대 내의 표사현상에 큰 영향을 미친다. 쇄파대 내의 부유사 농도가 장주기 변동을 하는 것은 가여ㆍ전중(1983), 시소 등(1985) 등에 의해 현지에서 관측되어 있다 또한 Beach and Sternberg(1988, 1991)는 장주기파가 발달한 때의 쇄파대 내 부유사 농도가 장주기파가 발달하지 않은 경우에 비해 3-4배의 값을 나타내는 것을 지적하면서 장주기파에 의한 내외해 방향(cross shore direction) 부유사 flux의 방향이 주파수나 저면으로부터의 높이에 의해 변화함을 제시하였다. (중략)

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.145-150
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• 2002

본 연구는 국내에서의 지역별 풍력자원을 조사하여 자연에너지인 풍력을 활용하고자 기상청의 기상 관측소 자료를 이용하여 분석하였던 바, 다음과 같이 요약 할 수 있다. 가. 평균풍속의 분포를 보면 제주고층이 10.8m/s로 가장 높았고, 순천이 0.6m/s로 가장적게 나타난 것으로 일반적으로 해안가나 내륙고산지대에서 높은 풍속을 보였다. 나. 풍속지속시간을 보면 대부분의 지역에서 3.0m/s 이상, 연간 5,000시간이상으로 나타나 풍력의 이용가능성을 알 수 있었다. 다. 풍력 에너지 밀도는 인천 142kWh/m$^3$, 제주도 400kWh/m$^3$, 대관령 280kWh/m$^3$, 울릉도 140kWh/m$^3$, 목포 200kWh/m$^3$및 군산 180kWh/m$^3$높게 나타났다.

• Agrochemical news magazine
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• v.23 no.9 s.182
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• pp.6-9
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• 2002

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.68-75
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• 2017

This paper presents the experimental and theoretical results of the dynamic responses of a pendular energy extractor in a two-dimensional wave channel. By adopting a wave maker with varying wave height and period, the dynamic responses of the pendular buoy were experimentally obtained. Furthermore, with the aid of the co-simulation of moving particle analysis and rigid dynamic analysis, the dynamic responses of the pendular system were evaluated. In order to validate the feasibility of the proposed wave power generator, the force tuning of the pendular system with restoring energy was carried out. The results provide proof of concept data for the development and design of a commercial model for horizontal wave power generators in the shoreline area.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.3
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• pp.595-605
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• 1994

The field observations. data analyses and numerical experiments are performed to investigate the short and long term beach deformation mechanisms in Haeundae beach. The schematic diagrams of deposition and erosion mechanism due to the attack of typhoons are described from the analysis on the beach widths and profiles. The short term beach deformation depends strongly on the characteristics of incident waves and wave-induced currents. The main incident wave and the calibration parameters of the shoreline change model are determined using the beach width data. Beacause the main incident wave approaches obliquly from the SE direction, the net westward longshore sediment transport occurs. Therefore the unbalance of longshore sediment budget in the east of the beach where the sediment source dose not exist causes a beach erosion. On the other hand, the deposited sand in the west is lost offshore by the storm wave action.

• Journal of the Speleological Society of Korea
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• no.67
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• pp.1-9
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• 2005

The lava-calcification which was found in Geunjisul located in Jeju-do (Korea) was investigated to analyse the cause of calcification through the internal factor of cave structure and surroundings in company with relevant ecological system. The volcanic cave is degenerated after formation from volcano lava extravasation, however, the cave became more stronger with solidification and petrification by the reinforced structure of calcification as the cement in concrete buildings unprecedentedly if the lava-calcification occurred in the cave. Such a Progressive Phenomena of lava-calcification was verified in progress first in Geonjigul located at Hyubjae-ri, but those would be found in other simiiar case of caves distributed and connected with seaside of shelly sand beach.

• Korean Journal of Plant Taxonomy
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• v.47 no.2
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• pp.112-118
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• 2017

Achillea alpina L. subsp. pulchra (Koidz.) Kitam., an unrecorded subspecies belonging to the genus Achillea of Asteraceae, was discovered and is illustrated here. It is known as an endemic species of Hokkaido, Japan, but we discovered it along the seashore at Uljin in Gyeongsangbuk-do, Korea. Having a relatively equally serrate or dentate leaf margin and sparsely villous involucres, this subspecies is easily distinguished from its related taxa. Based on its habitat, it was termed Gaet-top-pul in Korean. We provide a description, illustrations, photographs and a key of related taxa in Korea.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.3
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• pp.300-306
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• 2022

The distribution properties of airborne chlorides at the coasts of Jeju island were identified in this study. For this, Jeju island was divided into four regions-east, west, south, and north, and the airborne chlorides were investigated in those regions. And the regional and seasonal distribution properties of airborne chlorides were analyzed. Jeju island, which has a subtropical climate and is surrounded by ocean, has a great regional variation in the distribution properties of airborne chlorides, with a difference of more than 6 times between the eastern region, the highest region, and the southern region, the lowest region. In terms of seasonal properties, the airborne chlorides in eastern and western region were high in summer and fall, and in summer mainly due to typhoon. The airborne chlorides in northern region were high in winter due to the northwest wind, and the that of southern region were high in summer. Meanwhile, the airborne chlorides of Jeju island tends to be high compared to the eastern, western, and southern coasts of South Korea.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.37-37
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• 2022

밀은 세계 3대 작물로 국내 1인당 소비량은 지속적으로 증가하고 있다. 하지만 국내 밀의 유전적 배경 확대와 기후변화 신속 대응을 위한 국내 밀 유전자 풀의 확장은 밀의 질적 향상을 위해 매우 중요한 목표이다. 국내 자생 갯그령(Leymus mollis)은 해안가에서 번식하는 영년생 식물로 뿌리줄기를 이용한 왕성한 번식력을 가지고 있다. 또한, 해안가의 뜨겁고 염에 대한 적응성과 저항성을 가지고 있다. 이러한 특성은 밀 유전자 풀의 확장에 매우 유용할 것이다. 국내 밀 재배지 한계 극복을 위한 간척지 재배가 가능한 내염성 강화 밀 자원 개발을 위하여 모본인 보통 밀(Triticum aestivum L., Chinese Spring)과 부본인 갯그령을 원연교배하였다. 갯그령과 보통 밀의 원연 교배를 통한 종자 형성은 매우 어려우나 불가능한 것은 아니며, 최종적으로 10개의 교배 종자를 얻어 F₁ 식물체로 생장하는 과정에서 5 식물체는 고사하였고, 나머지 5 식물체는 영년생 특성인 뿌리줄기에 의해 새로운 줄기가 출현하는 것을 확인하였다. 또한, 갯그령의 DNA를 이용한 genomic in situ hybridization 방법으로 F₁ 식물체에서 갯그령의 염색체가 밀의 유전적 배경에 이입된 것을 확인하였다. F₂ 식물체는 모본인 보통 밀보다 긴 수장과 간장을 나타내고 이삭 수는 많았지만, 출수기는 보통 밀보다 3주 이상 늦어지는 것을 확인하였다. 내염성 평가를 위하여 F₂ 종자를 2% 소금물에서 발아시켜 생육이 좋은 식물체를 선발하여 50 cm 투명 아크릴 원통에 이식하고 2% 소금물을 지속적으로 관개하였다. 내염성 강화 F₂ 식물체는 염에 감수성을 보인 식물체에 비하여 상대적으로 긴 이삭과 종자 형성을 보였으며, 감수성 식물체는 종자 형성이 이루어지지 않았다. 또한, 내염성 강화 F₂ 식물체는 감수성 식물체에 비하여 좋은 뿌리의 신장과 천근성을 보였다. 이러한 갯그령의 식물학적 특성이 이입된 계통은 기후변화 대응, 환경 적응성 강화, 및 근권 강화에 좋은 작물 소재로 이용할 수 있다고 생각한다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.28 no.4
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• pp.48-54
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• 2024

NPP (Nuclear power plant) structures have been constructed near to the sea shore line for cooling water and exposed to steel corrosion due to chloride attack. Regarding NPP structures built in the UAE, chloride transport may be more rapid than those in the other regions since the temperature near to the coast is high. In this study, concrete samples with 5,000psi (35MPa) design strength grade were manufactured with the materials and mix proportions, which were the same as used in the UAE NPP structures, then chloride diffusion coefficients were evaluated considering temperature and curing age. The compressive strength and the diffusion coefficient were evaluated and analyzed for the samples with 28 and 91 curing days. In addition, chloride diffusion tests for 91-day-cured condition were carried out in the range of 20℃ to 50℃. The activation energy was obtained through converting the temperature slope to a logarithmic function and it was compared with the previous studies. The proposed activation energy can be useful for a reasonable durability design by using actual temperature-dependent chloride diffusion coefficient.