• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.3 no.2
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• pp.39-47
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• 1985

This study analyzes space resection and space intersection for terrestrial convergent photos taken on the straight line and the circular line by collinearity condition. The purpose is to investigate the properties of convergent case, and to suggest the optimum angle of convergence. Accuracies at convergent angles less than 20$^\circ$ are lower than those in normal photos, but by changing from 20$^\circ$to 90$^\circ$ the accuracy is improving with the highest at 90$^\circ$ convergence. Also, convergent photos on circular line is far higher than those on straight line in accuracies of results, therefore it is expected to apply this results effectively for precise analysis of various facilities.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1491-1497
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• 2011

One of the primary concerns in the design of welding devices is how to reduce the distance error between the welding path and the torch, especially when the path has a combination of circular and linear parts. This study investigated a mechanism for reducing the tracking error in the tangent area of a circular and linear path. A portable welding device, called a carriage, has been designed for a specific welding path by considering the distance error deviation. This welding carriage for vertical cover plate welding consists of a rail, a welding torch and the carriage body itself.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1994.10a
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• pp.121-125
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• 1994

본 논문에서는 Hu에 의해 고안된 random 탐색법과 조합된 tabu 탐색법(radnom tabu 탐색법)을 결합계수를 구하는 학습 알고리즘으로 직접 사용하여 국소적 최적해에 수렴하는 것을 방지하고, 수렴정도를 개선하는 새로운 방법을 제안한다. 이 방법을 배타적 논리합 문제에 적용하여 역전파법 및 tabu 탐색법을 이용한 오차역전파법과 비교한다. 그리고, 각 파라메터가 오차함수의 수렴에 미치는 영향을 조사한다.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05b
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• pp.793-798
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• 1995

알카리 및 알카리토금속, 전이금속원소, 액티나이드원소등 10개 원소로 구성된 질산매질의 모의 방사성용액에서 옥살산에 의한 Nd와 Am의 공침전 연구를 수행하였다. 모의용액중의 질산농도와 옥살산농도에 따른 Nd과 Am의 침전율과 정제도가 연구되었다. 각 원소들의 침전율은 옥살산이 증가함에 따라서 증가하고 질산농도에 따라서는 감소하였다. 각각 0.5M인 옥살산농도와 질산농도에서 Nd과 Am의 침 전율이 99%이상이 되고, 정제도 측면을 고려할 때 가장 좋은 것으로 판단되었다. Am은 Nd와 매우 잘 공침전됨을 확인하였으며, Zr이 존재할 시 Cs, Sr, Pd등과 공침됨을 알 수 있었다.

• Journal of the Earthquake Engineering Society of Korea
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• v.2 no.2
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• pp.87-94
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• 1998

Behavioral characteristics of shallow circular arches with dynamic loading and different end conditions are analysed. Geometric nonlinearity is modelled using Lagrangian description of the motion. The finite element analysis procedure is used to solve the dynamic equation of motion, and the Newmark method is adopted in the approximation of time integration. The behavior of arches is analysed using the buckling criterion and non-dimensional time, load and shape parameters which Humphreys suggested. But a new deflection-ratio formula including the effect of horizontal displacement plus vertical displacement is presented to apply for the non-symmetric buckling problems. Through the model analysis, it's confirmed that fix-ended arches have higher buckling stability than hinge-ended arches, and arches with the same shape parameter have the same deflection ratio at the same time parameter when loaded with the same parametric load.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1678-1681
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• 2005

The disk cam mechanism cam produce a positive motion with a relatively few components. In the present paper a shape design of cam using the relative velocity method and the machining information analysis using the circular interpolation are introduced. In the first part of the paper a machining information at each point using the circular interpolation is taken. This study purposes the analysis method of the cutting error due to the moving path of the cutter, so that we can lead to the optimum design in a disk cam mechanism..

• Journal of architectural history
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• v.7 no.4 s.17
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• pp.191-198
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• 1998

The form of Pantheon in Rome is graphically analyzed in relation to the angle of the Sun that varies through four seasons of the year. These are worked out in the Autocad drawing files for exactitude and efficiency. Some of the results suggest that the Pantheon is carefully designed to predict the equinoxes and the solstices.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1754-1755
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• 2007

영구자석을 사용한 마커가 설치된 자기장 이동 경로에서 이동 로봇의 경로 인식을 위한 위치인식 시스템이다. 저가의 홀센서를 일정 간격의 열로 배치한 센서를 설계 제작하고, 그 센서를 이용하여 측정된 마커의 자계 값을 이용하여 경로상의 위치를 인식할 수 있도록 하였다. 마커의 극성을 인식하는 새로운 방법을 제시하고, 인식된 극성을 코드화하여 경로상의 특이점들에 배치함으로써 경로 이동 중에 그 점들의 위치를 인식하도록 하였으며, 로봇은 그 위치에서 미리 정해진 행동을 하도록 프로그램 하였다. 센서들 간의 통신 방법을 논하였고, 각 센서들에서 얻어진 정보로부터 이동 로봇의 경로상의 위치인 측방향 변위 오차와 방향각 오차를 기하학적으로 산출한다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.5
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• pp.84-90
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• 2004

A prediction of SEE rates for a candidate microprocessor is made based on the ground experiment results with a proton accelerator. Populations of charged particles in space are estimated with numerical models such as AP8, JPL91 and CREME. The cross section curves that are previously obtained with the accelerator are then employed for SEE prediction. Both the high and low inclinations are considered for low-earth orbits with nominal altitudes of about 685km. The results show that the occurrence rate of SEEs for the candidate device is acceptable for low-inclinations, but can be considerable under worst conditions for high inclinations.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.10
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• pp.687-694
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• 2019

A circular composite spar in the wing of ultra-light aircraft is subjected to both bending moment and transverse shear loads. However, the beam being used in the aircraft may be inefficient because the design would not take into account the characteristics of the circular tube that supports the bending moment in top and bottom arc parts and the transverse load in left and right ones. Therefore, it is necessary to efficiently fabricate the circular tube beam by properly selecting the stacking sequences or the laminated composite structure. In order to increase both bending and transverse shear strengths of the beams, in this study, a cross-section of circular tube is divided into four arcs: top, bottom, left and right ones. The commercial program, MSC/NASTRAN is used to calculate vertical displacement and the normal and shear strains with variation of parameters such as division angle of arc and fiber orientation. Based on the results, the effective parameters for the new circular composite beam are presented to increase its bending and shear strengths.