• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.512-515
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• 2005

The Korean peninsula has a number of coastal sites where the rhythmic rising and lowering of water surface due to tides result in strong tidal current. The kinetic energy of these currents can be efficiently exploited by using tidal current turbines. The pilot tidal current power plant is to be constructed at the Uldolmok between Chindo and Haenam. Extensive coastal engineer ing research works have been carried out. This paper describes some observation results of field campaign, design of the supporting structure of a pilot plant of 1,000kW and a future tidal current power plant and so on.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.516-519
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• 2005

The pilot tidal current power plant is to be constructed at the Uldolmok between Chindo and Haenam, during next year. and extensive coastal engineering research works have been carried out. In this paper we describes some observation results of the tide and tidal current. as well as modeling work in order to investigate the tide and tidal current regime change in relation to the tidal current power plant (TCPP) construction. The special modeling skill in order to consider the turbine operation in the TCPP is developed and applied to the estimation for the flow regime change by the simple layout of the tidal current power plant.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.72-75
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• 2005

Recently, as the global warming by fossil fuels become social issues. the interest of renewable energy producing system is increasing rapidly. Among these, wind turbines are most highlighted because of its economic competitiveness. The tower occupying about $20\%$ of overall turbine costs, is one of the main components of wind turbine. Tower access door located to base part of the tower, is used to enter the tower. This is the main structural weak point because of door hole, weldment, etc. In this study, by FEM, we retrieved the maximum van Mises stress at door location and carried out fatigue analysis using stresses at weld toe locations of tower access door part.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.621-626
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• 2002

A satellite scatterometer is a microwave radar sensor used to measure the backscattering at a sea surface. This instrument transmits radar pulses to the sea surface and measure the radar energy reflected back towards the source. Changes in wind velocity make sea surface roughness change and then affect on backscattered power. This gives us information of sea surface wind speed. Directions of wind vectors are acquired by multiple, collocated, and nearly simultaneous measurements. It should be noted that the scatterometer observes not the wind directly but the wind stress vector relative to the surface current. This suggests the possibility that the satellite scatterometer winds can include the effect of the surface current. This study shows the evidence that scatterometer measure surface wind stress, not surface winds and presents the velocity structure of oceanic warm and cold eddies.

• Journal of Chest Surgery
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• v.15 no.2
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• pp.169-173
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• 1982

We have experienced two cases of complicated teratoma in anterior mediastinum. One case, 1-year-old female, has a huge anterior mediastinal teratoma involving almost all of the left pleural cavity with atelectasis of the left lung. The other case, 12-year-old female, has a anterior mediastinal teratoma with fistula between the teratoma and the bronchus of anteromedial basal segment of left lung. The bronchus has a bronchiectatic change with cell infiltration. We performed exploratory thoracotomy with complete excision of tumor mass in both cases and with additional resection of anteromedial basal segment of the left lung due to inflammation and necrosis in latter case. The patients had uneventful postoperative courses and were discharged in good condition. Histopathologic diagnosis of these were benign teratoma consist of skin, skin appendages, cartilage, connective tissue, and gut.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.421-424
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• 2004

한국 동해시 연안역에서 2001년 6월, 2003년 5월 및 2004년 5월 해상실험 및 실시간 모니터링 부이 시스템을 통해 수집된 해양관측(수온, 유속)자료와 SAR (Synthetic Aperture Radar)위성영상을 분석한 내부파의 물리적 특성을 정리하였다. 이를 토대로 음파전달 모델(RAM)을 통해 내부파에 의한 음파전달 영향을 파악하고, 음도파관 불변 이른(Waveguide invariant theory)을 적용하여 내부파에 의한 해양 변동성을 음향학적으로 정량화 하였다.

• Journal of Korean Neurosurgical Society
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• v.52 no.3
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• pp.257-260
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• 2012

Spinal extradural arachnoid cysts usually cause symptoms related to spinal cord or nerve root compression. Here, we report an atypical presentation of a spinal extradural arachnoid cyst combined with congenital hemivertebra which was presented as a retroperitoneal mass that exerted mass effects to the abdominal organs. On image studies, the communication between the cystic pedicle and the spinal arachnoid space was indistinct. Based on our experience and the literature of the pathogenesis, we planned anterior approach for removal of the arachnoid cyst in order to focus on mass removal rather than ligation of the fistulous channel. In our estimation this was feasible considering radiologic findings and also essential for the symptom relief. The cyst was totally removed with the clogged 'thecal sac-side' end of the cystic pedicle. The patient was free of abdominal discomfort by one month after the surgery.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.374-377
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• 2007

This paper deals with a pitch control for reducing load of the wind turbine system. To make a model of the wind turbine system, the Momentum Theory and Blade Element Theory are used. Considering wind shear, wind model was also built. Due to a difference of the wind speed between upper parts and lower parts of the sweep area, overturning moment of the wind turbine is generated. So, in this paper through analyzing of the system model of the wind turbine, a control algorithm which was able to achieve both maintaining power and reducing overturning moment was proposed. Using matlab simulink, controller performance was verified.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.391-394
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• 2007

The foundation insert is a tubular steel section which is embedded into the concrete of the foundation. The tower base section of the wind turbine is mounted on it. It has a top flange (L type) protruding far enough above the concrete to allow bolts to be inserted from underneath. The load is transmitted to the concrete at the base of the section through a T shaped flange. It has many holes for the reinforcements and the cables. The reinforcements of the concrete foundation run through the insert via a series of holes to bind the inner section to the outer section. Holes are provided for the power and communications cabling. The design follows normal European wind turbine practice, based on GL 2003 and Eurocode regulations.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.639-643
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• 2007

Tidal regime change with general hydrolic condition change is examined, according to Garolim Tidal Power Plant (TPP) operation. Numerical model has been developed for the Yellow and East China Seas region, in order to consider the tidal regime change by the TPP operation. The changes of tidal elevation and tidal current inside the Garolim bay are also investigated in details, along with examining the change of the tidal flat area with operation. The field measurement for the tide and current have been carried out for the validation of the numerical model and for understanding the state of current system in the present state.