• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제24회 춘계학술대회논문집
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• pp.413-422
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• 2005

본 연구에서는, 먼저 $Fine^{TM}/Turbo$의 신뢰성을 확보하기 위해 초음속 터빈의 실험 결과와 비교 해석하였다. 그 결과 $Fine^{TM}/Turbo$는 초음속 유동 현상을 비교적 정확하게 해석함을 알 수 있었다. 다음으로 Grid Independency Test를 통하여 3차원 터빈의 적합한 격자계를 선정하여. 3차원 초음속 터빈의 노즐-로터 상호작용에 관해 유동해석을 실시하였다. 터빈의 노즐-로터간의 축방향 간격은 점점 커질수록 높은 추력을 나타냈으며, 로터 블레이드의 Chamfering Angle 또한 Blade-Edge가 날카로워 질수록 추력이 증가하였다.

• 센서학회지
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• 제25권1호
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• pp.8-12
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• 2016

A planar, light-weight, and low-cost notch filter structure is required for the KSTAR ECEI (Electron Cyclotron Emission Imaging) system to protect the mixer arrays from spurious plasma heating power. Without protection, this heating power can significantly degrade or damage the performance of the mixer array. To protect mixer arrays, a frequency selective surface (FSS) structure is the suitable choice as a notch filter to reject the spurious heating power. The FSS notch filter should be located between the lenses of the ECEI system. This paper presents a 170 GHz FSS notch filter for the KSTAR ECEI sensor application. The design of such an FSS notch filter is based on the single-sided square loop geometry, because that makes it relatively insensitive to the incident angle of incoming wave. The FSS notch filter exhibits high notch rejection with low pass-band insertion loss over a wide range of incident angles. This paper also reviews the simulated and measured results. The proposed FSS notch filter might be implemented in other millimeter-wave plasma devices.

• 항공우주시스템공학회지
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• 제1권1호
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• pp.67-72
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• 2007

In this paper, numerical results for 3-D supersonic turbine flow have been firstly compared with the experimental results to verify results computed by $Fine^{TM}/Turbo$. It was found that $Fine^{TM}/Turbo$ can accurately predict flow characteristics within supersonic turbine. Next, an grid system for 3D turbine flow was optimized selected through grid independency test. Finally, the effect of axial gap between rotor and nozzle and chamfer angle of blade edge on the flow characteristics within 3-D supersonic turbine was analyzed with Frozen Rotor method.

• 한국전산유체공학회지
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• 제12권2호
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• pp.37-45
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• 2007

The hybrid Cartesian/immersed boundary method is applied to simulate fluid-structure interaction of a two-dimensional orbiting flexible foil. The elastic deformation of the flexible foil is modelled based on the dynamic equation of a thin-plate. At each time step, the locations and velocities of the Lagrangian control points on the flexible foil are used to reconstruct the boundary conditions for the flow solver based on the hybrid staggered/non-staggered grid. To test the developed code, the flow fields around a flapping elliptical wing are calculated. The time history of the vertical force component and the evolution of the vorticity fields are compared with recent other computations and good agreement is achieved. For the orbiting flexible foil, the vorticity fields are compared with those of the case without the deformation. The combined effects of the angle of attack and the orbit on the deformation are investigated. The grid independency study is carried out for the computed time history of the deformation at the tip.

• 한국실내디자인학회논문집
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• 제21권5호
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• pp.254-263
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• 2012

This study found out the change of spacial form of detached house in Korea on a 10-year basis from 1980s though analysis on the architecture of each period. For the subject houses of this study, the detached houses introduced repeatedly as excellent cases in technical journals for architecture were collected among those completed by architects who designed numerous houses and a survey was conducted on 18 detached houses of 18 architects among the in urban style houses in Seoul and suburban style houses in the suburbs of Seoul. Through this study, it could be found that, as the morphological application of traditional architecture was settled with spatial concept, the external spatial form of the detached houses in Korea after 1980s was changed to westernized form but the internal spacial form had been continuously changing suitable to our emotion by reflecting the living habit and taste with the traditional attitude to perceive and accept the nature. As for the change in the forms of interior space, vertical space with more than two floors became common. Front porch and stair hall, which were located at the center of a house and became an important spacial element that overlapped family's moving line, changed to open and bright space that used transparent glass and increased the space to contact the open air, reflecting our living habit and taste that preferred the feeling of internal openness. A Private space, main room, was more segmented and luxurious, and a public space, living room, secured the independency by getting close to symbolic yard. As for the change in the form of exterior space, the form of façade window has been changing in its location and size and brought free images due to the advancement of technology and material. The shape of roofs was borrowed from western style and a lot of geometrical forms that break away from the concept of angle rater and eaves are appearing.