• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.32-36
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• 2002

This paper presents the structural characteristic analysis of a centerless grinding machine with concrete bed. The centerless grinding machine is composed of grinding wheel head, regulating wheel head, concrete bed, wheel dresser and so on. Especially, the concrete bed is introduced to improve the static, dynamic and thermal characteristics of the centerless grinding machine. The structural analysis model of centerless grinding machine is constructed by the finite element method, and the structural characteristics in the design stage are estimated based on the structural deformation and harmonic response under the various testing conditions related to gravity force and directional farces

• International Journal of Aeronautical and Space Sciences
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• v.12 no.1
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• pp.84-91
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• 2011

A finite element analysis for the wing and landing gear of a composite target-drone air vehicle was performed. For the wing analysis, two load cases were considered: a 5g symmetric pull-up and a -1.5g symmetric push-over. For the landing gear analysis, a sinking velocity of 1.4 m/s at a 2g level landing condition was taken into account. MSC/NASTRAN and LS-DYNA were utilized for the static and dynamic analyses, respectively. Finite element results were verified by the static test of a prototype wing under a 6g symmetric pull-up condition. The test showed a 17% larger wing tip deflection than the finite element analysis. This difference is believed to come from the material and geometrical imperfections incurred during the manufacturing process.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.6
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• pp.241-247
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• 1999

This study presents the structural analysis of car a seat frame by the finite element method. The load-deformation characteristics of seat frame are simulated according to the test requirements by FMVSS. Three dimensional modeling technique is applied to the components of the seat frame. The shell, solid , gap and rigid elements are employed to model the car seat frame assembly. Numerical results show that the recliner and kunckle plate are identified as the possible weak part of frame, and the results are well consistent with the experimental static load test. The current analysis model can provide useful informations to design a new car seat and can reduce the overall design cost and time.

• Computational Structural Engineering
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• v.2 no.1
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• pp.47-53
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• 1989

An efficient model for three-dimensional analysis of multistory structures with flexible floor diaphrgms is proposed in this paper. Three-dimensional analysis of a building structure using a finite element model requires tedious input data preparation, longer computation time, and larger computer memory. The model proposed in this study is developed by assembling a series of two-dimensional resisting systems and is considered to overcome the shortcomings of a three-dimensional finite element model without deteriorating the accuracy of analysis results. Static and dynamic analysis results obtained using the proposed model are in excellent agreement with those obtained using three-dimensional finite element models in terms of displacement, periods, and mode shapes. Effects of floor diaphragm flexibility on seismic response of multistory building structures are investigated.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2000.11a
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• pp.161-164
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• 2000

In this paper, a finite element structural analysis for thin-walled open-section composite beams with elastic couplings has been performed. The analysis includes the effects of transverse shear across beam sections, torsion warping and constrained warping. Reissner's semi-complementary energy functional is used to obtain the beam st illness coefficients The bending and torsion related warpings and the shear correct ion factors are obtained as part of the analysis. The resulting theory describes the beam kinematics in terms of the axial, flap and lag bending, flap and lag shear, torsion and torsion-warping deformations. The static response has been validated against finite element predict ions, closed form solutions, and experimental data for rectangular sol id and I-beams with elastic couplings. The free vibration results are also compared with available literature.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.18 no.3
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• pp.311-320
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• 2005

In this paper an enhanced quadratic finite element for static and dynamic analysis of plate structures is presented. The performance of a proposed plate element is improved by the coupled use of non conforming displacement modes, the selective integration scheme, and the assumed shear strain fields. An efficient direct modification method is also applied to this element to solve the problem such as failure of the patch test due to the adoption of non conforming modes. The proposed quadratic finite element does not show any spurious mechanism and does not produce shear locking phenomena even with distorted meshes. It is shown that the results obtained by this element converged to analytical solutions very rapidly tough numerical tests for standard benchmark problems. It is also noted that this element is applicable to transient dynamic analysis of Mindlin plates.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.3
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• pp.265-274
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• 2011

This paper presents current state of the prediction simulator of structural characteristics of machinery equipment accuracy. Developed accuracy prediction simulator proceeds and estimates the structural analysis between the designer and simulator through the internet for convenience of designer. 3D CAD model which is input to the accuracy prediction simulator would simplified by the process of removing the small hole, fillet and chamfer. And the structural surface joints would be presented as the spring elements and damping elements for the structural analysis. The structural analysis of machinery equipment joints, containing rotary motion unit, linear motion unit, mounting device and bolted joint, are presented using Finite Element Method and their experiment. Finally, a general method is presented to tune the static stiffness at a rotation joint considering the whole machinery equipment system by interactive use of Finite Element Method and static load experiment.

• Structural Engineering and Mechanics
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• v.82 no.2
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• pp.205-224
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• 2022

This paper presents a refined finite element formulation for nonlinear static and dynamic analysis of sliding cable structures, overcoming the limitation of the existing approaches that neglect or approximate the friction, pulley dimension, temperature and geometric nonlinearity. A new family of elements with the same framework is proposed, consisting of the cable-pulley (CP) elements considering sliding friction, and the non-sliding cable-pulley (NSCP) elements considering static friction. Thereafter, the complete procedure of static and dynamic analysis using the proposed elements is developed, with the capability of accurately dealing with the friction at each pulley. Several examples are utilized to verify the validity and accuracy of the proposed elements and analysis strategy, and investigate the frictional, thermal and pulley-dimension effects as well. The numerical examples show that the results obtained in this work are in good accordance with the existing works when using the same approximations of friction, pulley dimension and temperature. By avoiding the approximations, the proposed formulation can be effectively adopted in predicting the more precise nonlinear responses of sliding cable structures.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.1190-1197
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• 2006

We have evaluated the structural stability of a platform screen door due to train wind pressure. The platform screen door was installed at the ground and underground station and had 65 meters in length. Also, the platform screen door was a safety device because it was placed between the train and the platform. The finite element analysis was used to calculate the stresses and deflections of platform screen door caused by wind pressure using ANSYS 10.0. Quasi-static analysis was introduced to save calculating time and check quickly structural performances when compared to those of transient analysis. The results show that structural stability of the platform screen door under train wind pressure is proven and quasi-static analysis can quickly check the structural integrity of platform screen door.

• International Journal of Aerospace System Engineering
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• v.6 no.1
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• pp.1-7
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• 2019

In the present study, structural safety and stability on the main wing and tail planes of the 1.2 ton WIG(Wing in Ground Effect) flight vehicle, which will be a high speed maritime transportation system for the next generation, was performed. The carbon-epoxy composite material was used in design of wing structure. The skin-spar with skin-stressed structural type was adopted for improvement of lightness and structural stability. As a design procedure for this study, the design load was estimated with maximum flight load. From static strength analysis results using finite element method of the commercial codes. From the stress analysis results of the main wing, it was confirmed that the upper skin structure between the second rib and the third rib was unstable for the buckling load. Therefore in order to solve this problem, three stiffeners at the buckled region were added. After design modification, even though the weight of the wing was a little bit heavier than the target weight, the structural safety and stability was satisfied for design requirements.