• Journal of the Korean Society for Advanced Composite Structures
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• v.1 no.3
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• pp.24-34
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• 2010

This paper analyzed the partial differential equations of laminated composite shells of revolution by using the finite difference method. The proof that numerical results are reasonable and accurate is obtained through converge ratio analysis and commercial program LUSAS for the structural analysis. The purpose of this study is to examine closely the engineering advantages and to analyze the structural behaviors of the anisotropic shells of revolution. Thus, the relevant reinforcement and most suitable arrangement of fiber to produce the highest strength are proposed through the numerical results according to a variety of parameter study. Namely, the distribution of displacements and stress resultants are analyzed according to the change of meridian's curvature, the ratio of height-width of shell, subtended angle, fiber angle, and so on. Using these distribution, the most suitable shell may be proposed to produce the highest strength. Also, the configuration of the entire laminated composite conical shells is analysed, and a variety of the design criterion of circular conical shell are proposed and studied in engineering view points.

• Journal of the Korean GEO-environmental Society
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• v.19 no.1
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• pp.31-36
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• 2018

Recently, as the building construction works have been activated, the environment in which the excavation work is proceeding in parallel with the existing structure and the adjacent excavation work is increasing. However, there is not a lot of research on this. In this study, numerical analysis was carried out for interaction analysis between former excavation construction and follow-up excavation on two excavation retaining structures in parallel with excavation. As a result of numerical analysis, if the supporting load of strut is not considered, it was analyzed that the displacement distribution in the structure can be underestimated and acting stress of strut is overestimated. It was analyzed that the support stress causes by the former excavation should be considered in order to simulate the actual behavior characteristic.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.17 no.2
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• pp.98-105
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• 2005

A new type breakwater is developed for small scale harbors and fishing ports with low design wave and soft ground. The structure of the developed breakwater is similar to the soldier pile used in soil excavation. Structural performance of the new type breakwater can not be accurately evaluated by numerical analysis due to nonlinearity of joints between piles and honelasticity of soil support. Therefore, this paper investigates the structural performance of the breakwater with experimental method and compares the results with numerical analysis.

• Bulletin of the Korean Space Science Society
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• 2003.10a
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• pp.71-71
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• 2003

과학로켓 3호에 탑재된 자력계의 데이터 분석을 통해서 로켓의 비행자세가 어떻게 비행시간에 따라 어떻게 변화했는지에 대해 논한다. 과학로켓 3호에 탑재된 로켓의 비행 자세 정보 획득을 위한 Fluxgate 자력계인 Attitude Information Magnetometer (AM)의 데이터 분석을 통해 로켓의 비행시간동안 자세가 어떻게 변화했는지 수치해석 프로그램 및 시뮬레이션을 통해 알아보았다 본 연구에서 사용한 수치해석 프로그램은 Spline 보정법, 다항식 수치법인 Bairstow Method, Least square method이며, 자체 개발한 로켓비행정보 획득용 프로그램과 OpenGL을 이용한 로켓의 3차원 시뮬레이션을 통해서 과학로켓 3호의 자세를 나타내는 roll, pitch, yaw의 변화를 알아보았다. 그리고, 이 결과를 이용하여 자력계가 자세제어에 적합한지도 분석하였다.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2001.04b
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• pp.31-33
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• 2001

잠열축열 그린하우스 난방 시스템의 난방특성을 분석하기 위하여 이에 대한 열평형 이론을 정립하고 수치해석에 의하여 컴퓨터 시뮬레이션 모델을 개발하고자 잠열축열 그린하우스 난방 시스템의 열저항 회로망을 구성하였다. 그리고 그린하우스의 피복재, 내부 공기, 토양표면, 잠열 축열재와의 열평형 방정식을 구성하였으며, Newton-Raphson반복법을 이용하여 수치해석을 하였고, 실험 분석을 통하여 수치해의 타당성을 검증하였다. 시뮬레이션 모델을 위하여 C언어를 사용하였으며, 겨울철 (11월-2월)의 기후 조건이 유사한 여러 날을 선정하여 온도, 태양강도, 상대습도, 토양 수분함량 등을 자료로 하여 모델링을 하였다. 여기에 사용된 토양 조건은 사양토로 건조한 상태를 유지하였다. 이상과 같은 분석에 의하여 그린하우스내 경시적 공기온도 변화와 열전달 현상의 실험치와 이론분석 결과가 잘 일치하고 있음을 알 수 있었다.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.160-160
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• 2016

토석류 재해규모의 예측이나 효과적인 사방 구조물의 검토에 있어 토석류 수치모형은 매우 중요하다. 따라서 본 연구에서는 토석류의 유동특성을 파악하고 토석류 피해지역의 정확한 분석을 통해 토석류 유출저감시설(사방댐)의 설치 위치 및 저감효과 등을 분석하였다. 이를 위해 토석류해석시 침식 및 퇴적작용 해석이 가능한 Hyper KANAKO모형을 이용하여 토석류 수치모델링을 수행하였고, 대상지역의 정확한 분석을 위해 지상LiDAR로 실측된 고정밀도 DEM자료를 구축하고 수치모델링을 통해 사방댐의 적정 설치 위치 및 제원에 따른 토석류 저감효과 등을 분석함으로써 토석류 저감 대책 수립 시 기본자료를 제공하고자 한다.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.2107-2108
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• 2011

전력계통의 절연설계에 있어 뇌과전압을 정확하게 측정하고 분석하는 것은 매우 중요하다 할 수 있다. 유도뢰 해석의 일환인 수치해석은 계산식을 기반으로 유도뢰 차폐효과에 대해 해석이 가능하나 이러한 수치적 해석은 선로정수, 뇌격전류의 크기 또는 접지저항 값이 변경되었을 경우 재계산을 하는데 다소 복잡한 과정을 거쳐야하기 때문에 이를 일괄적으로 처리할 수 있는 프로그램의 개발 필요성이 대두되었다. 이에 유도뢰 차폐효과 계산 프로그램을 MATLAB을 사용하여 개발하였다.

• Journal of KSNVE
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• v.9 no.3
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• pp.607-612
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• 1999

Natural frequencies of non-symmetrically tapered beams with simply supported ends were determined by solving the frequency equations. In the case of symmetrically tapered beams. the finite element method was adopted for frequency computation. Computed frequencies of tapered beams were expressed as functions of taper ratio. a. and sectional properties. ( m, n).

• Journal of the Korean Wood Science and Technology
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• v.36 no.3
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• pp.24-29
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• 2008

Numerical analysis model was used to analyse the behaviors of multiple bolted connections. Axial-bending element was supposed as basic model, and the effects of frame members and steel fasteners were classified for the behavior analysis. In the condition only two bolts were used, the traditional analytical methods, which show somewhat accuracy, have some advantages more than numerical analysis that need many time consuming, However, more many bolts were used in practical field condition. Also, it is impossible to analyse the behaviors of various bolts layouts and arrangements conditions by traditional analytical methods. Therefore, there is only numerical analysis method for the accurate behavioranalysis on the practical bolted connection condition. Therefore, numerical analysis method was applied on the various multiple bolted connections. On the result exactness and the reflection of connection condition, numerical analysis method showed the superiority more than widely used traditional empirical analysis methods as yield model.

• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.4
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• pp.77-86
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• 2016

A numerical analysis is performed to investigate the effect of a supply channel and jet hole arrangement on the heat flow characteristics of impingement jet. The jet holes in a supply channel are composed of a single or staggered array from the center of a leading edge channel. The software ICEMCFD is used to generate the structured grids for calculation domain and a CFD code CFX 15.0 to perform the simulation. The present solutions are validated by comparison with the experimental and numerical ones of others. A comparison of mass flow rates of impingement jets and Nusselt numbers on the impingement surface for the single or staggered arrays is made.