• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
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• pp.450-455
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• 1998

In this paper, finite element with embedded discontinuous line is introduced in order to avoid the difficulties of adding new nodal points along with crack growth in discrete crack model. With the discontinuous element using discontinuous shape function, stiffness matrix of finite element is derived and dual mapping technique for numerical integration is employed. Using the finite element program made with employed algorithms, algorithm is verified and fracture analysis of simple concrete beam is performed.

• 소성∙가공
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• 제8권3호
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• pp.313-318
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• 1999

Many products related to automobile and airplane industry have been manufactured by semi-solid forging. In this paper finite element analysis of product by combined extrusion in semi-solid state was performed and its experimental verification using A356 was conducted. distribution of solid fraction was analyzed and compared with the experimental microstructure in the product. In addition, distribution of temperature in the product was analysed by finite element method.

• 동력기계공학회지
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• 제21권1호
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• pp.37-42
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• 2017

A curved beam is one of the basic and important structural elements in structural design. In this paper, the authors formulated the computational algorithm for analyzing the free vibration of curved beams using the finite element-transfer stiffness coefficient method. The concept of the finite element-transfer stiffness coefficient method is the combination of the modeling technique of the finite element method and the transfer technique of the transfer stiffness coefficient method. And, we confirm the effectiveness the finite element-transfer stiffness coefficient method from the free vibration analysis of two numerical models which are a semicircle beam and a quarter circle beam.

• 한국정밀공학회지
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• 제22권10호
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• pp.202-209
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• 2005

In this study, two dimensional and three dimensional finite element models of lower first premolar were analyzed. The mandibular specimen including a premolar was obtained from a cadaver and scanned with micro-CT. Finite element method models were reconstructed from CT images at mid-sagittal plane of the tooth. Most studies have used a wide range of value(0.07${\~}$1000MPa) for elastic modulus of periodontal ligament. The elastic modulus of the periodontal ligament was analyzed by finite element method and compared with that of experiment model. This study indicated that the model without pulp was more suitable than that with pulp in two dimensional finite element analysis.

• 한국안전학회지
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• 제19권1호
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• pp.38-43
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• 2004

Many analysis methods, including finite element method, have been suggested and used for assessing the integrity of cracked structures. In the paper, in order to analyze arbitrary three dimensional cracks, the finite element alternating method is extended. The crack is modeled by the symmetric Galerkin boundary element method as a distribution of displacement discontinuities, which is formulated as singularity-reduced integral equations. And the finite element method is used to calculate the stress values for the uncracked body only. Applied the proposed method to several example problems for planner cracks in finite bodies, the accuracy and efficiency of the method were demonstrated.

• Structural Engineering and Mechanics
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• 제22권5호
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• pp.575-597
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• 2006

Enhanced three-dimensional finite elements for geometrically nonlinear analysis of cable-supported structures are presented. The cable element, derived by using the concept of an equivalent modulus of elasticity and assuming the deflection curve of a cable as catenary function, is proposed to model the cables. The stability functions for a frame member are modified to obtain a numerically stable solution. Various numerical examples are solved to illustrate the versatility and efficiency of the proposed finite element model. It is shown that the finite elements proposed in this study can be very useful for geometrically nonlinear analysis as well as free vibration analysis of three-dimensional cable-supported structures.

• 소성∙가공
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• 제25권5호
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• pp.325-331
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• 2016

In this paper, a three-dimensional part model is constructed for the finite element analysis of hemming models where hemming defects frequently occur. The roller path is modeled as the boundary condition with the one-dimensional beam element and the revolute joint model. With the constructed part model and the roller movement, a finite element analysis has been pursued in order to identify the hemming load and hemming defects such as wrinkling in the flange region. The analysis result shows that the maximum hemming load occurs in the intake situation while oscillatory behavior of the load is found especially when hemming the curved model because of wrinkle generation. This paper compares the amplitude and the period of wrinkle between the analysis result and the experiment, which shows good agreement with each other.

• 한국전산구조공학회논문집
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• 제17권1호
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• pp.1-10
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• 2004

최근, 유한요소해석견과의 신뢰도를 향상시키기 위하여 활발하게 연구되고 있는 적응유한요소해석은 반복계산을 통해서 해석결과의 오차가 사용자에 의해 지정된 허용오차와 같아지도록 하는 해석방법이다. 이와 간은 적응유한요소해석은 해석결과의 오차평가와 이에 따른 유한요소의 재구성과정으로 나누어진다. rp방법에서는 절점의 위치를 이동시켜 요소의 크기를 조절하는 r방법과 형상함수찻수를 증가시키는 p방법을 동시에 적용함으로써 적응해석의 유효성을 향상시키고자 하였다. 제안한 rp방법의 특성을 규명하고 적응해석의 유효성을 보이기 위하여 전형적인 이차원 평면문제들을 해석하고 그 결과를 검토하였다.

• Structural Engineering and Mechanics
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• 제9권1호
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• pp.89-97
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• 2000

A modified constitutive model has been developed for nonlinear finite element analysis of axisymmetric reinforced concrete structures, and then implemented into an existing finite element program. By comparing with the experimental results available, the present model has been validated.

• 대한전자공학회논문지
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• 제26권8호
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• pp.1137-1144
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• 1989

In this paper, for eliminating the spurious solutions which have been necessarily included in the solutions of earlier vectorial finite-element method, we have proposed the improved finite-element method for the analysis of dielectric waveguides in the three-component magnetic field.