• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.955-958
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• 2005

In this study, the wind load characteristics for a transmission tower is investigated considering the effect of the transmission lines through stochastic analysis. The assemblage of the transmission line and insulator are modeled as a double pendulum system connected to the SDOF model of the tower It is observed that the background component of the overturing moment induced by the wind response of the transmission line has considerable portion in the total overturning moment. Based on this result, a rotational viscoelastic damper (VED) is proposed for the mitigation of the transmission line reactions, which act as wind load transferred to the tower. To verify the effectiveness of the proposed strategy, time history analysis is conducted for different wind velocities and VED damping constants. From the analysis, the proposed VED is proved to be effective for mitigation of the background component rather than the resonance component of the transmission line reaction.

• 한국강구조학회 논문집
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• 제16권2호통권69호
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• pp.257-265
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• 2004

line-type 유한요소법을 이용하여 불균등 단부 모멘트를 받는 보의 비탄성 좌굴 거동에 대하여 연구하였다. 잔류응력은 단순형과 다항식형 모델을 채택하였으며 잔류응력으로 인해 발생하는 단면의 불균등 항복을 고려하였다. 본 연구에서 얻어진 비탄성 횡-비틀림 좌굴에 대한 결과는 강구조편람의 허용응력법에 의한 설계 경우와 비교하였다. 결과적으로, 강구조편람에 의한 설계는 중지간 보에서 중간 브레이싱이 있는 경우나 없는 경우 모두 과설계가 됨을 알 수 있었다.

• 한국컴퓨터산업학회논문지
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• 제4권10호
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• pp.643-654
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• 2003

택타일 영상을 사용하여 로봇 그리퍼 내부 작업 물체의 미끄럼 및 회전을 감지하는 기법을 제안해 본다. 기존에 제안된 모우멘트 불변량 사용방법의 경우 택셀 수 변화가 발생하는 경우 적용 할 수 없는 단점을 가지고 있다. 에지 ＆ 라인 불변량 특성을 이용한 경우 기본적으로 특정수 이상의 택셀을 가지고 있어야 하므로 택셀수가 적은 경우 적용 할 수 없다. 이 같은 문제점을 해결하기 위하여 택셀 영상을 분석하고 적용기법 결정인자를 추출한다. 이를 이용하여 필터링 문턱값을 설정하여 택타일 영상을 필터링하고, 결정인자에 따라 모우멘트 불변량 사용방법과 에지 ＆ 라인 불변량 사용 방법 중 적합한 기법을 채택하는 새로운 방법을 제안한다 컴퓨터 모의 실험과 하드웨어 실험에 적용한 결과 개선된 이동 및 회전 등 움직임 감지가 가능하였다.

• 한국지진공학회논문집
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• 제26권1호
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• pp.23-30
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• 2022

This study proposed a simplified finite element analysis procedure for designing the nonstructural masonry wall in the out-of-plane direction. The proposed method is a two-step elastic analysis procedure by bilinearizing the behavior of the masonry wall. The first step analysis was conducted with initial stiffness representing the behavior up to the effective-yield point, and the second step analysis was conducted with post-yield stiffness. In addition, the orthotropic material property of the masonry was considered in the FE analysis. The maximum load was estimated as the sum of the maximum loads in the first and second step analyses. The maximum load was converted into the moment coefficients and compared with those from the yield line method applied in Eurocode 6. The moment coefficients calculated through the proposed procedure showed a good match with those from the yield line method with less than 6% differences.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1014-1022
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• 2011

Urban transit operation is to manipulate the vehicle or train of urban transit to be operated on the basis of the installations such as track, power, communication, signaling and so on. It can be performed by manual or automated, or manned or manless operation considering its system built, operation efficiency, safety, etc. Because of the heavy impact directly to the safety of passenger transport, it has been managed strictly by the Regulation for Train Operation of Urban Transit according to Urban Transit Act. However, the present regulation has been basis of the manual operation mainly, it is crossing beyond the limitation of application to the manless operation which is being introduced moment to moment. It is needed increasingly to revise the regulation for the manless operation which is close at hand now. In this paper, we examined and analysed the cases of manless operation of urban transit planed within the country such as Busan 4th Line, Shinbundang Line, Busan-Kimhae Line, etc. based on the present regulation, and proposed the review of considerations to reflec the manless operation to the regulation to be revised.

• 한국전자파학회논문지
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• 제15권4호
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• pp.345-352
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• 2004

본 논문은 페라이트 필름을 기반으로 하는 마이크로스트립 선로로부터 여기되는 정자표면파의 복사 임피던스를 full-wave모멘트 해석법을 이용하여 계산하였다. 마이크로스트립 선로 폭과 페라이트 필름 두께 변화에 따른 여 기 특성 변화도 분석하였다. 정자파 근사에 의하여 계산된 복사 저항값은 주파수가 증가할수록 실험 값과 차이가 심해지나, full-wave 해석에 의하여 계산된 복사 저항값은 실험값에 매우 근접함을 알 수 있었다.

• 대한전기학회논문지:전력기술부문A
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• 제48권1호
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• pp.76-81
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• 1999

The degree of relative similarity between 2D patterns is obtained using Open-Ball Scheme. Open-Ball Scheme employs a method of transforming the geometrical information on 3D objects or 2D patterns into the features to measure the relative similarity for object(patten) recognition, with invariance on scale, rotation, and translation. The feature of an object is used to obtain the relative similarity and mapped into [0, 1] the interval of real line. For decades, Moment-Invariant Method has been used as one of the excellent methods for pattern classification and object recognition. Open-Ball Scheme uses the geometrical structure of patterns while Moment Invariant Method uses the statistical characteristics. Open-Ball Scheme is compared to Moment Invariant Method with respect to the way that it interprets two-dimensional patten classification, especially the paradigms are compared by the degree of closeness to human's intuitive understanding. Finally the effectiveness of the proposed Open-Ball Scheme is illustrated through simulations.

• 대한기계학회논문집A
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• 제30권3호
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• pp.269-278
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• 2006

This paper proposes slip line fields for bending of unequally notched specimens in plane strain that have a sharp crack in one side and a sharp V-notch in the other side. Depending on the back angle, two slip line fields are proposed, from which the limit moment and crack tip stress fields are obtained as a function of the back angle. Excellent agreement between slip line field solutions with those from detailed finite element limit analysis based on non-hardening plasticity provides confidence in the proposed slip line fields. One interesting point is that, for the unequally notched specimen, the difference between the crack tip triaxial stress for tension and that for bending increases significantly with increasing the back angle. This suggests that such a specimen could be potentially useful to investigate the crack tip constraint effect on fracture toughness of materials. In this respect, the possibility of designing a new toughness testing specimen with varying crack tip constraint is discussed.

• 전산구조공학
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• 제23권3호
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• pp.69-74
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• 2010

• 한국강구조학회 논문집
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• 제10권4호통권37호
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• pp.615-627
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• 1998

곡선 격자형교의 최대 전단력. 최대 휨 모멘트, 최대 순수 비틈모멘트, 최대 뒴비틈모멘트, 최대 바이모멘트를 계산하기 위하여 곡선 격자형교에 작용하는 활하중의 재하위치를 찾는 것이 중요하고 영향선을 이용하면 이 값들을 쉽게 계산할 수 있다. 등 변단면 I-형 곡선격자형교를 해석하기 위해. 본연구에서는 Vlasov의 기초미분방정식을 이용하고, 이의 수치적 해석을 위해 유한차분법을 적용하여 등 변단면의 최대부재력이 발생하는 위치에서 등 변단면의 휨모멘트, 전단력, 순수비틈모멘트, 뒴비틀모멘트, 바이모멘트의 영향선을 구하여 비교 제시하였고 이를 이용해 최대부재력이 발생하도록 하는 활하중의 재하위치를 구하였다.