• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.6
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• pp.107-115
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• 2002

A parametric study has been conducted to evaluate the effects of finite element modeling methods on the internal loads, sizing and the weight of the multi-spar aircraft wing structures. The wing is idealized into total 18finite element models and subjected to 4typical external load conditions. An automatic sizing algorithm based on MSC/NASTRAN and MSC/PATRAN is developed. The results show that the critical part affection the internal loads and weight of the structure is wing skin. Effect of modeling of the spar and rib on the structural behavior is not manifest. On the contrast to the general expectation, the models using the bending-resistant elements show the heavier weight than ones by the elements without bending stiffness. From this results, designers of multi-spar wing are recommended to construct the finite element model considering the bending stiffness, or to check the characteristics of the structure before modeling.

• Computational Structural Engineering
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• v.4 no.1
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• pp.83-94
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• 1991

This paper presents an efficient and accurate method for nonlinear analysis of frame structures by idealized structural unit method. The main idea behind the present method is to minimize the computational effort by reducing the number of unknowns. An explicit form of the tangential elastic stiffness matrix of the element is derived by the principle of virtual work. The ultimate limit state of the element is judged on the basis of the formation of a plastic hinge mechanism. The elasto-plasto-plastic stiffness matrix of the element is derived by plastic node method and the post-ultimate stiffness equation is formulated under a simple analytic consideration. A comparison between the present solution and the existing experimental and other numerical result for unit column member and simple frame structure is made. If is clear from the result of this study that the present method is very useful because the computing time required is very small while giving the accurate solution.

• Journal of the Society of Naval Architects of Korea
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• v.28 no.2
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• pp.307-317
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• 1991

A displacement-based finite element method is presented for the geometrically nonlinear analysis of eccentrically stiffened plates. The nonlinear degenerated shell and eccentric isobeam(isoparametric beam) elements are formulated on the basis of total Lagrangian and updated Lagrangian descriptions. To describe the stiffener's local plate buckling mode, some additional local degrees of freedom are used in the eccentric isobeam element. The eccentric isobeam element can be affectively employed to model the eccentric stiffener just like the case of the degenerated shell element. A detailed nonlinear analysis including the effects of stiffener's eccentricity is performed to estimate the critical load and the post buckling behaviour of an eccentrically stiffened plate. The critical buckling loads are found higher than analytic plate buckling load but lower than Euler buckling load which are the buckling strength requirements of classification society.

• Journal of the Korean Society of Hazard Mitigation
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• v.6 no.2 s.21
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• pp.9-15
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• 2006

Structures of Civil Engineering have been designed with a safety as their main purpose. However recently, the greenness side of the technology of civil engineering regarded as most Important and also utility values and stability of the structures. Also developments in the technology make materials to be higher strength and they shortened scales and stiffness of the structural members. This means that it brings an immoderate deflection and vibration of bridge structures simultaneously. Accordingly, this study ai ed to find and estimate the most idealized structure models on the effects of the deflection and vibration of bridges from the traffic lane load and human vibration - the main pass of bridge structures.

• Proceedings of the Korean Magnestics Society Conference
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• 2006.11a
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• pp.154-155
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• 2006

• Journal of Korean Electronics
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• v.11 no.3
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• pp.28-32
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• 1991

• Proceedings of the Membrane Society of Korea Conference
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• 2001.05a
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• pp.88-92
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• 2001

• Bulletin of the Korean Space Science Society
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• 1998.10a
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• pp.14-14
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• 1998

• Proceedings of the Korean Magnestics Society Conference
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• 2003.06a
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• pp.254-255
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• 2003

• The Journal of the Korean dental association
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• v.45 no.3 s.454
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• pp.132-135
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• 2007