• Journal of the Korean Society for Marine Environment & Energy
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• v.14 no.1
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• pp.11-18
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• 2011

Wave overtopping reef system with guide vanes convert incident wave energy on the reef type structures into electric power. Previous studies decided shape parameters likes slope, height of the sloping arm and shape of guide vane. In this paper, using these shape parameters produce 1/7 scale model and construct integration scale model system combining water pressure head turbine, power generation, power control, operating control and monitoring system. In these systems, we measure the overtopping and power generation with different wave heights and periods and compare the results with the previous studies. This was confirmed designed overtopping and power generation, then we suggest efficient control system.

• Korean Journal of Pharmacognosy
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• v.32 no.2 s.125
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• pp.128-134
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• 2001

The Korean folk medicine 'Am Cho' has been used as the folk remedy for diuretic, stomach and liver cancer. The botanical origin of the crude drug has not been studied pharmacognostically. To clarify the botanical origin of 'Am Cho', the comparative morphological and anatomical characteristics have been studied of Lepisorus species growing wild in Korea, i.e. L. annuifrons, L. onoei, L. thunbergianus, L. ussuriensis and 'Am Cho' form Korea. As a result, it was clarified that 'Am Cho' from Korea was derived from Lepisorus onoei.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.4
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• pp.323-330
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• 2010

An efficient wave energy converter with new overtopping flow device on which spiral reefs are attached is proposed by Maritime and Ocean Engineering Research Institute in Korea and its candidate substructures such as monopile, tripod and jacket are designed. This study investigates modal characteristics of the substructures by analyzing natural frequencies and mode shapes. Based on the modal analysis results, relative strength, governing modes and some complementary design strategies of each candidate substructure are compared and discussed considering water depth conditions.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.127-129
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• 2018

RadarBeacons are navigational equipment that helps the navigators avoid dangerous rocks, such as heavy fog, nighttime, etc. when ships operate, or when visibility is bad. The existing antenna was researching the development of the advanced radar eacon (Enhanced Radar Beacon) for improving the development of the next generation racon with the AIS (Automatic Identification System) function.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2023.05a
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• pp.241-242
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• 2023

등부표는 선박의 안전한 항행을 지원하는 시설인 항로표지의 한 종류로 항행하는 선박에게 암초나 수심이 얕은 곳의 소재를 알리거나 항로의 경계를 알리기 위해 침추를 해저에 정치하여 해상의 고정위치에 띄워 놓은 등화가 설치된 것을 말한다. 등부표의 표체는 해저에 정치된 침추와 체인으로 연결하며 체인의 길이는 수심의 1.5 ~2.5배로 하여 표체를 계류한다. 등부표는 조류, 바람 등 외력에 의해 이출거리가 발생하여 일정한 패턴으로 선회반경이 형성되나 외력으로 인하여 정상범위에서 벗어나 유실, 위치이동 등이 발생할 수 있고 이는 선박추돌 등 항해안전 사고로도 이어질 수 있다. 이러한 등부표 사고는 물적 피해비용과 이용자의 안전운항에 대한 심리적 부담감 또는 위험감수 등의 추가적인 행정소요 비용이 발생할 수 있다. 따라서 선박의 안전한 도선을 위해서는 등부표의 이출범위와 위치가 변할 수 있음을 염두해 둘 필요가 있다. 이와같은 등부표로 인한 사고 예방과 안전한 도선을 위해 등부표 이출범위와 안전도선에 관한 연구를 하였다.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.5
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• pp.1-11
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• 2010

The outdoor space of an elementary school is the most familiar and most educational area for children. A paradigm shift in education has demanded a new role and direction for these outdoor spaces. The construction of children-friendly spaces, however, lags behind. The child-participatory design process is very meaningful at a time when many outdoor spaces have difficulties in reflecting the varied and specific demands of children. This study realized the necessity for a design that includes a child-participatory design process in construction the outdoor spaces of elementary schools. Through reference study and a theoretical approach of related laws, this study established a child-participatory design process model and applied it to Seoul Don-Am Elementary School. The design process included playing games and providing interesting tools to increase the participation of children in suggesting and presenting their opinions more freely. The design process of this study is described in five steps(eliciting interest in and recognition of the target space, Understanding children's expectations and the expressing thereof, Establishing factors for planning, Visualizing and arranging spaces, and Decision-making and building a final design plan). This process was applied to the planning and design of an outdoor space for Seoul Don-Am Elementary School. In this study, it is clear that the design of the participators and experts have a different purpose. Thus, the process of the design has more meaning than the final product. In addition, it is expected that an improvement in both tangible and intangible designs will be seen. Using a participatory design process, this study successfully improved the facilities and arrangement planning of an outdoor space. At the same time, it also enhanced the interest and participation of children in the process of creating the kind of school they desire. The significance of this study is that it has suggested an effective model to reflect the demands of children, the true users of the outdoor space, and the results were actually applied to elementary school outdoor planning and designing. This study enhanced the awareness of school members in the process of building the school's outdoor space.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.2
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• pp.86-91
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• 2008

Ships operating in littoral sea are likely to be subjected to accidental load such as stranding. Once she has damage on the hull structure, her ultimate strength will be reduced. This paper is to investigate the effect of the stranding damage on ultimate strength of ship structure by using a series of collapse tests. For the experiment, 720 mm $\times$720 mm in section and 900mm in length of five box-girder models with stiffeners were pre- pared. Of the five, one has no damage and faur have an diamond shaped damage which represents the shape of rock section in seabed. The damage size is different between models. Among the damaged models, the damages of 3 of them were made by cutting the plate and one by pressing to represent stranding damage. Experiments were carried out under pure bending load and the applied load and displacements were recorded. The ultimate strength is reduced as the damage size increases, as expected. The largest damaged model has the damage size of 30% of breadth and its ultimate strength is reduced by 21% than that of no damaged one. The pressed one has lower ultimate strength than cut one. This might be due to the fact that the plate around the pressed damage area effect negatively on the ultimate strength.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.3
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• pp.166-172
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• 1997

In order to exterminate effectively starfish, Asterias amurensis inhabited a village fishing grounds and shellfish farms on coast of Korea, Mop and sledge gear were made and sea trials for capture efficiency of starfish by each gear and towing distance were carried out by commercial dredger on the coast of Keojedo from April to May in 1995. As Starfish mop and sledge were slowly dragged over the bottom at the same time, starfish became entangled in bunches of twine and netting respectively. The gears were hauled up at intervals to remove the starfish and hand-picking operations on vessel were conducted. The results obtained are as follows : Two gears were smoothly slidden over the sea bottom and captured numerous starfish. The optimal towing distance by each gear was 300 to 500 m.The capture efficiency of starfish species by sledge was 57% compared with 43% of that by mop but mixed rate with fish or shellfish of the former was 21 times as high as that of the letter. It was concluded from sea trials that moping was effective in shellfish farms, because the mop outfit causes little damage to useful shellfishes and the mixture of starfish with fish or shellfish was low, whereas sledging can be used to clean uncultivated areas free of shellfish where starfish population is very heavy and common fishing grounds in which bottom material is rock or gravel.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.64.2-64.2
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• 2011

해상용(offshore) 부이(bouy)는 선박의 항로를 지시하거나 암초, 침몰선 등 항해상의 위험물을 알리기 위해 사용 되며, 야간을 위해 등화장치를 설치한 것을 등부표라 한다. 등부표는 야간 점등을 위해 자체 전력 생산시스템을 갖추고 있으나, 기존의 태양광을 이용한 전력 시스템은 해상 환경에 따른 제약이 많아 안정적인 운영이 어려우므로 풍력 발전기(wind turbine)를 이용한 하이브리드 전력 생산시스템으로의 전환이 필요한 실정이다. 선행 연구는 수직축(vertical axis) 양력(lift) 및 항력(drag) 조합형 해상용 풍력발전기 개발에 대하여 수행하였으나, 본 논문에서는 풍력발전기의 효율 증대를 위해 날개 길이 및 후면부 절개 비율에 따른 수직축 풍력발전기 특성에 대하여 연구하였다. 풍력발전기의 설치조건은 선행연구와 동일하게 등명구 교체 작업을 원활하게 하기 위하여 설치 공간을 $1m{\times}1m$로 제한하였으며, 등부표의 구조를 고려하여 최상단에 지지 프레임을 별도로 구성 하였다. 풍력발전기의 블레이드는 0.6mm의 알루미늄 박판을 절곡하여 NACA 4418의 외형을 가지도록 제작하였고, 블레이드 설계 시 에어포일의 후면부를 절개하여 양력과 항력을 효과적으로 이용하며 저속과 고속에서 높은 효율을 가지도록 설계하였다. 또한 블레이드 날개 길이와 후면부 절개 비율에 따른 풍력발전기 특성을 실험을 통해 비교하여 기준 해상 풍속에서 블레이드 설계 최적화를 수행하였으며 비교 모델 대비 약32% 발전량이 증가한 설계변수 조합을 구하였다.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.17 no.1
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• pp.55-59
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• 2005

The present data concerns the wave height distribution around the Ieodo underwater rocks and it was obtained from a 3D hydraulic model experiment which was performed in 1999 by Konkuk University and Korea Ocean Research and Development Institute. The experiment was separately undertaken for 4 different wave directions (NNW, SE, S, NNW) under which wave heights were measured at every 1m interval within the preset grid area, 16m×18m. It was observed that the wave breaking occurred on the top of the Ieodo model for all wave directions. This data may be effectively used for improving or verifying the performance of numerical wave propagation models in the area with the local breaking wave zones.