• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.748-751
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• 2001

Monoleaflet polymer artificial heart valve was known to show remarkable improvement in antithrombosis and pressure drop compared with other type of artificial valve. In this investigation monoleaflet the vertical and horizontal deflection pattern of polymer heart valve with three types of supporting members straight member, and two curved members was analysed using the large deformation nonlinear finite element method.

• 한국정밀공학회지
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• 제20권3호
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• pp.120-124
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• 2003

Monoleaflet polymer artificial heart valve was known to show remarkable improvement in antithrombosis and pressure drop compared with other type of artificial valve. In this investigation of monoleaflet heart valve the vertical and horizontal deflection pattern of polymer heart valve with three types of supporting members, straight member and two curved members were analysed using the large deformation nonlinear finite element method.

• 한국농공학회지
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• 제43권5호
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• pp.106-115
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• 2001

This paper deals with the free vibrations of horizontally curved beams partially supported on elastic foundations. Taking account of the effects of rotatory inertia and shear deformation, differential equations governing the free vibrations of such beams are derived, in which the Pasternak foundation model is considered as the elastic foundation. Differential equations are numerically solved to calculate natural frequencies and mode shapes. The experiments were performed in which the free vibration frequencies of such curved beams in laboratorial scale were measured and these results agreed quite well with the present studies. In numerical examples, the circular, parabolic, sinusoidal and elliptic curved members are considered. The parametric studies are performed and the lowest four frequency parameters are reported in tables and figures as the non-dimensional forms. Also the typical mode shapes are presented.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.425-428
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• 2015

New technologies using a CNC machine are being developed to reduce the production cost of free-form buildings. For production of free-form members using such technologies, vast free-form buildings should be first split into multiple panels that are productible. Taking into consideration of the curved surface of free-form members, the segmented free-form panels may vary in shape and size, which may cause a lot of errors. In addition, it is time-consuming for the work. However, the current panelizing work is completed with the trials and errors of engineers and architectural designers even in large-scale projects, which results in increased construction duration and cost. Thus, it is necessary to develop a technology for panelizing free-form panels so as to maximize the economic feasibility of production technologies for free-form concrete members. The study intends to develeop automatic panelizing algorithms of free-form buildings considering the curved surface and size of free-form panels and the production conditions. The developed algorithms will be useful in applying the production technologies of free-form buildings using CNC machine and reducing the cost.

• 한국안전학회지
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• 제17권1호
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• pp.99-104
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• 2002

아크축(arch axis)의 연장(extensibility) 및 회전관성(rotatory inertia)을 고려한 곡선보(curved beam)의 평면내(in-plane) 자유진동을 미분구적법(DQM)을 이용하여 다양한 경계조건(boundary conditions)과 굽힘각(opening angles)에 따른 진동수(frequencies)를 계산하였다. DQM의 결과를 다른 수치해석결과와 비교하였으며, DQM은 적은 요소(grid points)을 사용하여 정확한 해석결과를 보여주었다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.875-880
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• 2001

This paper deals with the free vibrations curved beams with elastic springs. Taking into account the effects of rotatory inertia and shear deformation, differential equations governing the free vibrations of such beams are derived, in which each elastic spring is modeled as a discrete Winkler foundation with very short longitudinal length. Differential equations are solved numerically to calculate natural frequencies and mode shapes. In numerical examples, the circular, parabolic, sinusoidal and elliptic curved members are considered. The parametric studies are conducted and the lowest four frequency parameters are reported in tables and figures as the non-dimensional fonns. Also the typical mode shapes are presented.

• 한국안전학회지
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• 제14권1호
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• pp.199-207
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• 1999

곡선보(curved beam)의 평면내(in-plane)와 평면외(out-of-plane)의 자유진동을 해석하는데 differential quadrature method (DQM)를 이용하여 다양한 경계조건(boundary conditions)과 굽힘각 (opening angles)에 따른 진동수(frequencies)를 계산하였다. DQM의 결과는 엄밀해(exact solution) 또는 다른 수치해석(Rayleigh-Ritz, Galerkin 또는 FEM) 결과와 비교하였으며, DQM은 적은 요소(grid points)를 사용하여 정확한 해석결과를 보여주었다.

• 한국전산구조공학회논문집
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• 제20권4호
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• pp.417-425
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• 2007

곡선보(curved beam)의 회전관성(rotatory inertia) 및 전단변형(shear deformation)을 고려한 면외(out-of-plane) 자유진동을 해석하는데 미분구적법(DQM)을 이용하여 고정-고정 경계조건(boundary conditions)과 다양한 굽힘각(opening angles)에 따른 진동수(frequencies)를 계산하였다. DQM의 결과는 엄밀해(efact solution) 또는 다른 수치해석 결과와 비교하였으며, DQM은 적은 요소(grid points)를 사용하여 정확한 해석결과를 보여주었다.

• 한국산학기술학회논문지
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• 제7권5호
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• pp.793-800
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• 2006

곡선보(curved beam)의 회전관성(rotatory inertia) 및 전단변형(shear deformation)을 고려한 평면내(in-plane) 자유진동을 해석하는데 미분구적법(DQM)을 이용하여 고정-고정 경계조건(boundary conditions)과 다양한 굽힘각(opening angles)에 따른 진동수(frequencies)를 계산하였다. DQM의 결과는 엄밀해(exact solution) 또는 다른 수치해석(Rayleigh-Ritz, Galerkin 또는 FEM) 결과와 비교하였으며, DQM은 적은 요소(grid points)를 사용하여 정회한 해석결과를 보여주었다.

• 한국터널지하공간학회 논문집
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• 제6권4호
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• pp.279-290
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• 2004

이 논문은 I-단면 곡선강지보 (curved steel rib)의 등분포 하중 하에서, 비틀림 (warping)을 포함한, 외평면 (out-of-plane)의 안정성을 해석하였다. 미분구적법 (differential quadrature method, DQM)을 이용하여 다양한 경계조건, 굽힘각 (opening angles)과 강성매개변수 (stiffness parameter)에 따른 임계하중 (critical loads) 및 임계하중 매개변수 (dimensionless buckling parameter)를 계산하였고, Differential quadrature method (DQM)의 해석결과를 타 이론과 비교 분석 하였다. 또한 두 경계조건 (고정-고정, 고정-단순지지)하에서의 새로운 결과를 제시하였고, DQM을 이용한 곡선강지보의 좌굴해석은, 비교적 적은 요소 (grid points)를 사용하고도, 타 이론에 의한 해석적 결과에 비해 정확성과 안정성을 보여주었다.