본 논문은 영화 『헤드윅』의 주인공‘헤드윅’의 드랙퀸 분장과 이희문의 드랙퀸 분장에 대하 여 연구하였다. 이희문의 드랙퀸 복장이 국내 다양한 TV 프로그램과 공연에서 한국적 드랙퀸의 모습을 보인다는 점에서 연구가 시작되었으며 이희문의 드랙퀸 분장에 대한 차별점 분석을 목적으 로 하였다. 연구 방법으로는 영화『헤드윅』에서 헤드윅이 공연하는 장면에서 입은 모든 드랙퀸 의상의 종류와 특징에 대해 정리하였고 국내 TV와 YouTube(유튜브) 채널 그리고 라이브 공연에서 활발히 활동하고 있는 이희문의 드랙퀸 복장도 분석하였다. 본 연구의 선행 연구 논문으로는 드랙 퀸의 젠더 정체성 분석과 헤드윅의 공연 의상분석이 주를 이루고 있다. 본 논문에서는 헤드윅의 젠더 수행성보다는 드랙퀸 분장을 엔터테인먼트적인 요소로 활용하였다는 점에 집중하였다. 이희 문의 드랙퀸 분장은 그가 소속되었던 <씽씽 밴드>를 중심으로 분석하였고 <씽씽 밴드> 해체 이후 그의 새로운 여러 공연을 참고하였다. 이희문의 드랙퀸 분장은 그의 인터뷰 내용과 라디오 출연 또는 방송 출연에서 직접 이야기한 내용을 중심으로 비교 연구를 진행하였다. 연구 결과 이희문의 드랙퀸 분장은 엔터테인먼트적인 요소를 활용하여 다양한 예술 장르와 방송, 미디어에 등장하였 으며 이것은 앞으로 다양한 예술 장르가 엔터테인먼트적인 요소로 활용되어 미디어와 공연에서 시도될 수 있을 것으로 예측하였다.

Magnesium alloy is the lightest practical metal. It has excellent specific strength and recyclability as well as abundant reserves, and is expected to be a next-generation structural metal material following aluminum alloy. This paper investigated the possibility of thin plate fabrication by applying a overheating treatment to the melt drag method, and investigating the surface shape of the thin plate, grain size, grain size distribution, and Vickers hardness. When the overheating treatment was applied to magnesium alloy, the grains were refined, so it is expected that further refinement of grains can be realized if the overheating treatment is applied to the melt drag method. By applying overheating treatment, it was possible to fabricate a thin plate of magnesium alloy using the melt drag method, and a microstructure with a minimum grain size of around 12 μm was obtained. As the overheating treatment temperature increased, void defects increased on the roll surface of the thin plate, and holding time had no effect on the surface shape of the thin plate. The fabricated thin plate showed uniform grain size distribution. When the holding times were 0 and 30 min, the grain size was refined, and the effect of the holding time became smaller as the overheating treatment temperature increased. As the overheating temperature becomes higher, the grain size becomes finer, and the finer the grain size is, the higher the Vickers hardness.

AZ31 magnesium alloy was used to manufacture a thin plate using a melt drag method. The effects of roll speed, molten metal temperature, and molten metal height, which are the basic factors of the melt drag method, on the surface shape, the thickness of the thin plate, Vickers hardness, and microstructure of the thin plate were investigated. It was possible to manufacture AZ31 magnesium alloy thin plate at the roll speed range of 1 to 90 m/min. The thickness of the thin plate, manufactured while changing only the roll speed, was about 1.8 to 8.8 mm. The shape of the solidified roll surface was affected by two conditions, the roll speed and the molten metal height, and the Vickers hardness of the manufactured magnesium alloy thin plate value ranged from Hv38~Hv60. The microstructure of the thin plate produced by this process was an equiaxed crystal and showed a uniform grain size distribution. The grain size was greatly affected by the contact state between the molten metal and the solidification roll, and the amount of reactive solids and liquids scraped at the same time as the thin plate. The average grain size of the thin plate fabricated in the range of these experimental conditions changed to about 50-300 μm.

To improve the shortcomings and expand the advantages of the single-roll melt drag method, which is a type of continuous strip casting method, the melt drag method with a molding belt is applied to AZ31 magnesium alloy. By attaching the forming belt to the melt drag method, the cooling condition of the thin plate is improved, making it possible to manufacture thin plates even at high roll speed of 100 m/min or more. In addition, it is very effective for continuous production of thin plates to suppress oxidation of the molten metal on the roll contact surface by selecting the protective gas. As a result of investigating the relationship between the contact time between the molten metal and the roll and the thickness of the sheet, it is possible to estimate the thickness of the sheet from the experimental conditions. The relationship between the thin plate thickness and the grain size is one in which the thinner the thin plate is, the faster the cooling rate of the thin plate is, resulting in finer grain size. The contact state between the molten metal and the roll greatly affects the grain size, and the minimum average grain size is 72 μm. The thin plate produced using this experimental equipment can be rolled, and the rolled sample has no large cracks. The tensile test results show a tensile strength of 303 MPa.

An investigation is performed to clarify the manufacturing conditions of pure magnesium and AZ31 magnesium alloy thin plate using the melt drag method. By the melt drag method, suitable for magnesium molten metal, pure magnesium can be produced as a continuous thin plate with a thickness of 1.4 mm to 2.4 mm in the range of 5 m/min to 20 m/min of roll speed, and the width of the thin plate to the nozzle outlet width. AZ31 magnesium alloy is able to produce a continuous sheet of thickness in the range of 5 m/min to 30 m/min in roll circumferential speed, with a thickness of 0.6 mm to 1.6 mm and a width of the sheet matching the nozzle outlet width. In the magnesium melt drag method, the faster the circumferential speed of the roll, the shorter the contact time between the molten metal and the roll, and it is found that the thickness of the produced thin plate becomes thinner. The effect of the circumferential roll speed on the thickness of the thin plate is evident in the low roll circumferential region, where the circumferential speed is 30 m/min or less. The AZ31 thin plate manufactured by the melt drag method has a finer grain size as the thickness of the thin plate decreases, but it is currently judged that this is not the effect of cooling by the roll.

해상풍력발전기 설치선의 동적응답을 분석하기 위하여, 불규칙 파 정보를 고려한 시간영역 기반 비선형동적해석이 필요하다. 고전적인 단자유도 시스템은 가장 기본적으로 동적효과를 계산하는 방법이지만, 실제의 무게 중심 불일치, 비정규적인 파도 하중 그리고 항력의 비선형을 고려하지 못하는 제약조건들을 갖고 있다. 그리하여 불규칙 파를 고려한 다중 자유도 모델이 유사한 문제에 해답을 찾는데 폭넓게 사용되고 있다. 불규칙 시간영역 해석은 정확한 계산 결과를 제공하지만, 수렴 데이터의 수렴도가 민감하여 복잡하다. 이러한 제약점들을 극복하기 위하여 본 논문은 시간영역 해석 결과를 통하여 수정된 동적증폭계수를 개발하였으며, 기존보다 복잡성이 개선되면서 계산 시간을 획기적으로 단축하였다. 다양한 변수를 기준으로 한 시간영역 해석을 통하여 새롭게 개발된 동적증 폭계수는 단자유도 방법보다 더 높은 정도를 갖고 있으며, 예측이 가능하다.

Changes in the fishing grounds for four drag-bagnet fisheries (large trawl, large pair trawl, large Danish seine and middle Danish seine) were investigated by year and sea-blocks in Korean waters. We used catch and effort data by sea-block (latitude × longitude: 30´ × 30´) of the National Institute of Fisheries Science (NIFS) and yearly fishing production statistics of the Korean statistic information service from 2008 to 2014. The main benthic habitat of fishing ground was sand and sandy mud material. The average swept areas for the four fisheries were 181.7 km2, 606.4 km2, 2,720.9 km2 and 252.8 km2, respectively. The main fishing ground was around Jeju Island and the eastern South Sea. The main fishing ground moved to the northern part of the South Sea during the study period due to a closure of fishing grounds and changes in the target species.

The production of turbulence near a wall is the governing mechanism of the turbulent drag from external flow around bodies and in internal flows involving turbulence. The pocket is closely associated with the occurrence of the large Reynolds stress producing motions, and therefore implicitly involved with the turbulence production process. Within the wall region, hot-wire measurements show that a strong vortex forms within the pockets. This vortex is the rearrangement of existing sublayer vorticity and its amplification. The work in this area has been applied to the prediction and reduction of drag. The study is focused on the time scale of the pockets. The relationship between pocket time scale and modified wall has been found. By changing the upstream boundary condition at the wall the time scale of pockets were increased.

관내에서 이동하는 물체 주위의 유동에 대한 연구는 대부분 비정상상태가 아닌 정상상태의 종단속도 조건 하에 이루어져있 으므로 이에 대한 유체역학적 분석이 요구되고 있다. 이에 본 연구에서는 다양한 직경의 원통형 관 안에서 9.81m/s2으로 비정상 등가 속 운동을 하는 3D 구에 작용하는 힘을 전산유체역학을 이용하여 분석하였다. 유한 체적 기반 CFD 코드 인 Fluent 19.0을 사용하였으 며, 상대 운동 프레임과 난류 모사를 위한 SST k-ω 모델을 적용하였다. 선행연구 결과와의 비교를 통해 본 연구의 해석방법이 타당함 을 보이고 있다. 또한 후류 분석을 통하여 항력 변화를 설명하고, 벽면효과에 의한 항력 증가를 정량적으로 분석하였다.

The flow-surface interaction and resulting pockets is the case of a turbulence boundary layer. Conditionally sampled hot-wire measurements within the wall region show that a strong vortex forms within the pocket, bordering the upstream portion, which stay in the wall region. This vortex is the result of the rearrangement of existing sublayer vorticity and its amplification. The work in this area has been applied to the prediction and reduction of drag. The study is focused on determining change in the length scale of the pockets. An important relationship between pocket and modified wall has been found. By changing the upstream boundary condition at the wall, the length scale of pockets were decreased.

층류 경계층 내 반구에 의해 유기되는 말굽와류를 흡입 제어했을 때 후류영역에서의 마찰저항 변화를 측정하였다. 이를 위해 회류수조에서 유동가시화를 실시하여 최적의 자유유속, 반구 크기 및 흡입제어 구멍 크기를 결정하였고, 반구 후류영역에 설치된 평판과 연결된 동력계로 표면 마찰저항 감소를 측정하는 실험을 수행하였다. 평판에 설치된 반구 전방에는 유입 유동에 의해 반구를 감싸는 말굽와류가 생성되며 그 주위 와도 방향에 의해 후류영역으로는 빠른 유속의 유동이 유입되어 머리핀 와류 생성을 촉진시킨다. 따라서 반구 전방에 생성되는 말굽와류 세기를 흡입 제어에 의해 약화시킴으로써 반구 좌우측으로 길게 형성된 유속방향 와류가 후류영역으로 공급하는 에너지는 감소하게 된다. 즉, 반구 전방의 말굽와류를 제어함으로써 후류영역으로부터 생성되는 헤어핀 와류 발생 주파수가 줄어 들게 된다. 염료 주입을 이용한 유동 가시화 영상을 해석한 결과로 머리핀 와류의 발생 빈도가 흡입제어에 의해 36.4 % 감소되었고, 후류 영역에서 측정된 표면 마찰저항은 2.3 % 감소되는 것으로 나타났다.

An elliptic blending Reynolds stress transport equation model for Newtonian fluids has been extended to predict polymer-induced drag reduction FENE-P fluids. The conformation tensor equation which is related to the polymer stress is adopted from the model form of Resende et al., and the models of redistribution and dissipation rate terms for the Reynolds stress transport equation are considered by the elliptic blending equation. Also, the new model terms for viscoelastic turbulent transport and viscoelastic dissipation in the Reynolds stress transport equation are introduced to consider the polymer additives effect. The prediction results are directly compared to the DNS data to assess the performance of the present model predictions.

Fuel consumption in fisheries is a primary concern due to environmental effects and costs to fishermen. Much research has been carried out to reduce the fuel consumption related to fishing operations. The fuel consumption of fishing gear in fishing operation is generally related to hydrodynamic resistance on the gear. This research is to propose a low drag generated midwater trawl in terms of the gear design improvement using simulations. The results from the simulation were verified with results that mirrored the model experiments. From the results, the resistance force of the proposed gear decreased to 29% compared to that of the current gear. Furthermore, the gear performance also improved with increased gear mouth compared to the current one. Therefore, the proposed gear will be helpful to reduce the greenhouse gases from fishing operation. It will also contribute to the fishing industry by saving fuel.

In this paper, it suggests how to input what it needs under gesture based which is able to put its text 3 times faster than an existing way with voice based by a person who is a visually impaired person with a smart device that is flat display without a physical button. The suggesting way is a text input method based on gesture that after setting the touch display of the smart phone to 8 directions, then, it inputs number, English/Korean tests and special characters with initial location and central point of input texts following drag motion of the users or it controls and processes all applications in the smart devices naturally. It tries to prove efficiency of this method through real test to the visually impaired.

매년 증가하고 있는 풍해에 대한 대책으로서의 내풍설계는 필수적이다. 사과나무 지주시스템의 내풍설계를 위해서는 우선적으로 사과나무에 작용하는 풍하중을 파악해야 하고, 이를 위해서는 사과나무의 항력계수 산정이 필요하다. 기존 항력계수 산정 방법에서 발생할 수 있는 실험적 오차 등의 문제점을 보완하고자, 하중 측정 장치의 제작을 통한 풍하중 직접 측정 및 이를 통한 항력계수의 역추정 과정을 수행하였다. 풍속이 증가할수록 항력계수는 감소하며 점차 수렴하는 경향을 나타냈으며, 풍속 30m/s 일 때, 전면적 기준 약 0.176, 순면적 기준 약 0.356 의 값을 갖는 것으로 나타났다.

본 연구는 지표항력모수화법과 공간해상도 설정에 대한 WRF 중규모모델내 지표풍속모의 성능을 평가하였다. 지표풍속 보정효과는 지형이 복잡한 한반도를 대상으로 연구하였다. 두 가지 새로운 지표항력모수화법과 수평 및 연직해상도를 가지고 총 5가지 실험(CTRL, Exp_JD, Exp_MO, Exp_h2, 그리고 Exp_l38)을 수행하였다. 1995년 한 해 동안 10m와 1000hPa에서 모의된 풍속을 검증 하였다. 실험결과, 지표풍속모의에 대한 최고성능은 WRF 모델내 아격자규모의 지표항력모수화법을 적용하고 연직층을 38개로 설계 한 실험 Exp_l38에서 나타났다. 10m 고도(1000hPa)에서 풍속 Bias와 RMSE가 각각 0.18(-2.65), 0.83(2.73)m/s였다. 이 연구에서 제안 한 MO의 지표항력모수화법과 연직층의 상세화가 풍속모의 설계는 WRF 모델을 활용하여 보다 정확한 바람정보를 생산하고 활용하는데 있어서 도움이 될 것이다.

In this study, the capability of an existing analysis method for the fluid-structure-soil interaction of an offshore wind turbine is expanded to account for the geometric nonlinearity and sea water drag force. The geometric stiffness is derived to take care of the large displacement due to the deformation of the tower structure and the rotation of the footing foundation utilizing linearized stability analysis theory. Linearizing the term in Morison’s equation concerning the drag force, its effects are considered. The developed analysis method is applied to the earthquake response analysis of a 5 MW offshore wind turbine. Parameters which can influence dynamic behaviors of the system are identified and their significance are examined.