• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.398-398
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• 2010

To determine the molecular directionality of PI chains depending on rubbing condition, we measured the angle resolved near edge X-ray absorption fine structure (NEXAFS) spectra at C K-edge of the rubbed PI films. Twisted nematic mode PI (PI-TN) and in plane switching mode PI (PI-IPS) were introduced to examine the effect of rubbing conditions on the chain directionality. The average tilt angle a of the PI molecules was estimated through the measured intensity change of $C=C\;{\pi}^*$ in NEXAFS C K-edge spectrum by controlling the stage speed and the pile contact depth. After rubbing, the irregular molecular direction changed to a regular direction with a molecular tilt angle of $51.2^{\circ}$ for PI-TN and $49.6^{\circ}$ for PI-IPS at the rubbing condition of the roll speed of 1000 rpm, stage speed of 50 mm/sec, and file contact depth of 0.3 mm. The molecular tilt angle $\alpha$ was linearly decreased in the PI-TN and PI-IPS samples with increasing depth of the pile contact.

• Structural Engineering and Mechanics
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• 제18권3호
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• pp.377-388
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• 2004

Based on the basic equations of elasticity, free-edge effects on stresses in cross-ply laminated plates are found by using the state space method. The laminates are subjected to uniaxial-uniform extension plate, which is a typical example of general plane strain problem. The study takes into account material constants of all individual material layers and the state equation of a laminate is solved analytically in the through thickness direction. By this approach, a composite plate may be composed of an arbitrary number of orthotropic layers, each of which may have different material properties and thickness. The solution provides a continuous displacement and inter-laminar stress fields across all material interfaces and an approxiamte prediction to the singularity of stresses occurring in the boundary layer region of a free-edge. Numerical solutions are obtained and compared with the results obtained from an alternative numerical method.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1315-1318
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• 2004

Based on fuzzy 2-mean classification and template matching method, we propose a new algorithm to detect the edges of an image. In the algorithm, fuzzy 2-mean classification can classify all pixels in the mask into two clusters whatever the mask in the dark or light region; and template matching not only determines the edge's direction, but also thins the detected edge by a set of inference rules and, by the way, reduces the impulse noises.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(4)
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• pp.7-10
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• 2000

There are many Problems such as low detection ratio, velocity and increase of false hit ratio on the detection of gradual scene changes with the previous shot transition detection algorithms. In this paper, we Propose an improved dissolve detection method using color information on low-frequency subband and edge elements on high-frequency subband. The Possible dissolve transition are found by analyzing the edge change ratio in the high-frequency subband with edge elements of each direction. Using the double chromatic difference on the lowest frequency subband, we have the improvement of the dissolve detection ratio. The simulation results show that the performance of the proposed algorithm is better than the conventional one for dissolve detection on a diverse set of uncompressed video sequences.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1701-1704
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• 2005

We developed an machine vision method for navigation control of a traveling automatic guided vehicle(AGV) on desired trajectory with guided marks. The formulated EDF accumulates the edge magnitude for edge directions. The EDF has distinctive peak points at the vicinity of trajectory directions due to the directional and the positional continuities of desired trajectory. Examining the EDF by its shape parameters of the local maxima and symmetry axis results in identifying whether or not change in traveling direction of an AGV has occurred. Simulation results show that the presented method is useful for navigation control of AGV.

• Journal of Mechanical Science and Technology
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• 제18권12호
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• pp.2273-2283
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• 2004

The vortical flows over sharp-edged delta wings with and without a leading edge extension have been investigated using a computational method. Three-dimensional compressible Reynolds-averaged Navier-Stokes equations are solved to provide an understanding of the effects of the angle of attack and the angle of yaw on the development and interaction of vortices and the aerodynamic characteristics of the delta wing at a freestream velocity of 20 m/s. The present computations provide qualitatively reasonable predictions of vortical flow characteristics, compared with past wind tunnel measurements. In the presence of a leading edge extension, a significant change in the suction pressure peak in the chordwise direction is much reduced at a given angle of attack. The leading edge extension can also stabilize the wing vortex on the windward side at angles of yaw, which dominates the vortical flows over yawed delta wings.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 추계종합학술대회
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• pp.479-482
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• 2003

영상으로부터 검출된 에지는 원 영상에 대한 위치와 모양 등에 대한 다양한 정보를 포함하고 있으므로, 이러한 에지를 검출하기 위한 많은 연구가 이루어지고 있다. 그리고, 최근 신호처리 분야의 새로운 기법으로 제시된 웨이브렛 이론들의 발전과 더불어 웨이브렛 변환은 영상의 에지를 포함한 특이점들을 분석하는 분야에 널리 응용되고 있다. 따라서, 본 논문에서는 영상의 라인 폭에 의존하지 않는 웨이브렛 함수를 사용하여, 웨이브렛 변환 데이터의 국부 최대값과 기울기의 방향, 그리고 위치 정보로부터 원 영상의 에지를 검출하였다.

• 한국광학회지
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• 제8권1호
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• pp.7-13
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• 1997

기존에 제작된 칼날주사형 OTF 측정장치의 물체부와 상분석부를 개선하여 측정을 자동화함으로써 MTF 측정 정확도를 향상시켰다. 여러 가지 크기를 갖는 핀홀과 슬릿들을 물체로 사용하였고, fishtail edge를 상분석부의 수평방향에 45.deg로 부착시킴으로써 radial과 tangential 방향의 MTF를 동시에 측정할 수 있도록 하였다. 또한 상분석부의 스텝핑 모터 구동장치와 측정 컴퓨터 프로그램을 개선하였고, SIRA 그룹의 50nm 표준렌즈를 사용하여 OTF 측정장치의 측정 정확도를 평가하였다.

• Journal of Biosystems Engineering
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• 제24권5호
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• pp.453-462
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• 1999

At the time of discontinuing the publishing of RDA Journal of Farm management and agricultural engineering the present paper is to review the research results produced since 1962 to 1998. During the three decades, from 1960s to 1980s, the main research efforts were focused o mechanization of rice farming which contributed in food grain productions. In the 1990s, the research direction was shifted to horticultural productions and producing high quality agricultural products. We had put stress on practical use of farm mechanization, mainly on transplanting and seeding operation for rice and upland and horticultural crops productions and harvest and threshing machinery developments, in which we thought our research direction had not been quite right. However, in the future we are going to promote mechanization on livestock and upland crops productions. Furthermore, we have a plan to employ cutting edge technologies in agricultural machinery developments in order to automate and unman all farm operations satisfying the needs of advanced agricultural mechanization technology in the twenty first century.

• 한국기계연구소 소보
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• 제4권2호
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• pp.49-63
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• 1982

In this paper, a classical gust problem is treated by using the numerical lifting¬-surface theory to verify the effect of gust-a sudden fluctuating fluid velocity around an object, which is normal to the main stream direction-on the hydrody¬namic forces, especially the mean thrust in upstream direction, acting on the two¬-dimensional flat plate. In this case, the mean thrust wholly resorts to the leading edge suction, and it is the same situation to the case of the heaving plate in uniform flow. The ph¬enomenon of leading edge suction is very important for the flapping propulsion of animals, typical to fish and birds, and can be related to the prediction of the hydrodynamic forces acting on marine propellers operating in gustlike wakes of ships. The results of this paper can be easily superposed to those of the reference [1J in order to solve the problem of the two-dimensional oscillacting plate in gust