• Proceedings of the Computational Structural Engineering Institute Conference
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• 1991.10a
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• pp.33-39
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• 1991

This Paper presents a geometrically nonlinear behaviors of shell problems by using the three-dimensional curved shell element, which includs large displacements and large rotations. The standard formulation of the geometrically nonlinearity is restricted to the assumption of infinitesmal rotation increments. This standard formulation for the displacement function is numerically improved by considering the second order expansions of Tayler series. The nonlinear behaviors of the single and double curved shells are compared wi th the other results.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.6
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• pp.36-41
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• 1998

The objective of this study is to investigate effects of prebuckling on the buckling of laminated composite cylindrical shells. axial compression is considered for laminated composite cylindrical shells with length to radius ratios. The shell walls are made of a laminate with several symmetric ply orientations. This study was made using finite difference energy method, utilizing the nonlinear bifurcation branch with nonlinear prebuckling displacements. The results are compared to the buckling loads determined when membrane prebuckling displacements are considered.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.2
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• pp.49-58
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• 1997

The objective of this study is to investigate effects of prebuckling on the bucking of laminated compostie cylindrical shells, Both axial compression and lateral pressure are considered for laminated composite cylindrical shells with length to radius ratios. The shell walls are made of a laminate with several symmetric ply orientations. The study was using finite difference energy method, utilizing the nonlinear bifurcation branch with nonlinear prebuckling displacements. The results are compared to the buckling loads determined when membrane prebuckling displacements are considered.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1998.03a
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• pp.112-116
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• 1998

The objective of this study is to investigate effects of prebuckling on the buckling of laminated composite cylindrical shells. Axial compression is considered for laminated composite cylindrical shells with length to radius ratios. The shell walls are made of a laminate with several symmetric ply orientations. This study was made using finite difference energy method, utilizing the nonlinear bifurcation branch with nonlinear prebuckling displacements. The results are compared to the buckling loads determined when membrane prebuckling displacements are considered.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.335.2-335
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• 2002

Non-singular boundary element method (BEM) codes are developed in acoustics application. The BEM code is then used to calculate unknown boundary surface normal displacements and surface pressures from known exterior near field pressures. And then the calculated surface normal displacements and surface pressures are again applied to the BEM in forward in order to calculate reconstructed field pressures. (omitted)

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.887-890
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• 1996

In this study, based on the assumption that the displacements of suspension systems under the external forces are very small, a linear form of elastokinametic equations in terms of infinitesimal displacements and joint reaction forces are derived. The equations can be applied to any form of suspensions once the type of kinematic joints and bushings are identified. The validity of the method is proved through the comparison of the results from the more complex solution offered by ADAMS

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1998.04a
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• pp.123-130
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• 1998

The probability of unseating failure of the bridge spans under earthquakes is investigated. Seismic excitations are simulated as nonstationary processes by combining a stationary process and an intensity function. For computational convenience, a simplified single-degree-of-freedom model is adopted, which retains the dynamic characteristics of the original brige motion in concern. The time history analysis for the developed single degree-of-freedom model are carried out to evaluate the response processes, and the probabilistic characteristics of response displacements are evaluated. The reliability analysis of the bridge against the unseating failure is performed with the statistical information of the maximum displacements of responses.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.10a
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• pp.161-168
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• 2002

To evaluate seismic performance of bridges, two procedures far capacity spectrum method are presented. The capacity spectrum procedures include the reduction factor-ductility-period relationship in order to construct the inelastic demand spectra from the elastic demand spectra. Application of the procedures is illustrated by example analysis. Maximum displacements estimated by the procedures are compared to those by inelastic time history analysis for several artificial earthquakes. The results show that the maximum displacements estimated by the procedures are, on overall, smaller than those by the inelastic time history analysis

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.10a
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• pp.173-176
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• 1997

A refined plate theory including the effects of transverse shearing is used to predict the free vibration frequencies, mode shapes and stress distributions in spinning laminated composite plates. In this theory, the displacements are expressed by trigonometric series representation through the thickness. In the series for the displacements only the first few terms are retained. The model is validated by comparing the results for isotropic plates with those available in the literature.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.538-541
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• 2004

We describe a method for the detection of nanometer scale displacements of nanoelectromechanical resonators. We also present an analysis of the mechanical motion of these devices. We evaluate the effectiveness of the detection technique by detecting displacements from a series of nanomechanical doubly clamped beam resonators with decreasing dimensions.