• Journal of Aerospace System Engineering
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• v.3 no.3
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• pp.13-16
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• 2009

Aircraft flight control surfaces which are one of the most important elements of safety allow a pilot to adjust and control the aircraft's flight attitude. This paper is described of the control surface deflection angle measuring device. Data analysis through ground test and flight test can provide reliability of this device using the present system. It is also shown that measuring system is capable of detecting failure of control surfaces.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.861-864
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• 2005

A LCD glass plate is supported by multi-pin and golf-tee type support. In the FEM analysis, the support condition is treated as simply supported boundary .condition. In this study, the optimization on the location of multi-simply support is conducted. The size optimization method of ANSYS 8.0 is used as the optimization tool to search for the optimal support location of LCD glass plate. In the manufacturing process, the support condition is a fatal factor of quality control of LCD production. From the results of optimization, deflection decreases 51% compared with the original model.

• Structural Engineering and Mechanics
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• v.20 no.4
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• pp.405-420
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• 2005

In this paper, a hybrid/mixed nonlinear shell element is developed in polar coordinate system based on Hellinger/Reissner variational principle and the large-deflection theory of plate. A numerical solution scheme is formulated using the hybrid/mixed finite element method (HMFEM), in which the nodal values of bending moments and the deflection are the unknown discrete parameters. Stability of the present element is studied. The large-deflection analyses are performed for simple supported and clamped circular plates under uniformly distributed and concentrated loads using HMFEM and the traditional displacement finite element method. A parametric study is also conducted in the research. The accuracy of the shell element is investigated using numerical computations. Comparisons of numerical solutions are made with theoretical results, finite element analysis and the available numerical results. Excellent agreements are shown.

• Bulletin of the Korean Mathematical Society
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• v.58 no.1
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• pp.71-111
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• 2021

We consider the boundary value problem for the deflection of a finite beam on an elastic foundation subject to vertical loading. We construct a one-to-one correspondence �� from the set of equivalent well-posed two-point boundary conditions to gl(4, ℂ). Using ��, we derive eigenconditions for the integral operator ��M for each well-posed two-point boundary condition represented by M ∈ gl(4, 8, ℂ). Special features of our eigenconditions include; (1) they isolate the effect of the boundary condition M on Spec ��M, (2) they connect Spec ��M to Spec ����,α,k whose structure has been well understood. Using our eigenconditions, we show that, for each nonzero real λ ∉ Spec ����,α,k, there exists a real well-posed boundary condition M such that λ ∈ Spec ��M. This in particular shows that the integral operators ��M, arising from well-posed boundary conditions, may not be positive nor contractive in general, as opposed to ����,α,k.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2010.10a
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• pp.556-563
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• 2010

The main noise source of the rotary compressor for air conditioner was analyzed by using the measurement of sound intensity, modal analysis and operational deflection shape(ODS) analysis. In this study, the key noise source of rotary compressor was an accumulator, and noise was sharply increased due to the accumulator's resonance which has a big contribution to the noise. To reduce the excessive noise generated from accumulator, structural modification through ODS analysis were applied. Its validation was conducted by the measurement of noise and vibration on the accumulator's surface. The total noise was significantly reduced by 4.2dB(A).

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.340-343
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• 2007

In this paper, we present our method to reduce vibration of the base plate of a refrigerator by avoiding resonance between base plate and compressor operation. To verify the modes of the base plate, FE models of the base plate with free-free condition and applied boundary condition were built and validated by results from experimental modal analysis. Operating Deflection Shape analysis was applied to find the sensitive area on the base plate during compressor operation. In optimization process, Finite Difference Method - based sensitivity analysis is used to detect the most sensitive area. Finally, based on this numerical result, we will make beads on the base plate to reduce vibration of refrigerator.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.5 no.1
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• pp.13-20
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• 1999

Not only is it important that the physical properties of the paperboards be appropriate for the intended end use, but the proper arrangement of the component in the built-up board is essential for attaining the optimum moment of inertia and the maximum load-carrying ability in a box. It is known to be impossible to estimate the stress distribution and deflection pattern by experiments or theoretical analysis when the corrugated fiberboard get the bending force. This study was tried theoretical and finite element analysis to analyze structural strength characteristics of corrugated fiberboards. If the linerboard and corrugating medium of every corrugated fiberboards is made from the same material, the location of neutral axis comes close to inside liner in order of DMA, DM, DMB, SW and DW, and moment of inertia of area decreases in order of DMA, DMB, DW, DM and SW. With the finite element analysis, deflection of applied loads represented SW, DM, DMA, and TW in the order of their value.

• Journal of the Korean Wood Science and Technology
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• v.23 no.3
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• pp.8-15
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• 1995

This analytical study was carried out to make quality and productivity up in designing the frame-type furniture with semi-rigid joint by understanding the mechanical and structural behavior of the joint and by evaluating the validity of application of the time-saving Finite Element Method to its structural analysis. Slope deflection equation for rigid joint was modified to describe the moment-rotation behavior of semi-rigid joint and the joint stiffness factor(Z) could be calculated to lessen the experimental expense. It was proved that Finite Element Analysis with imaginary elements having equivalent MOE to the semi-rigid joint could be the alternative method for the structural analysis of the frame-type furniture, comparing the internal rotation of the 2-dimensional beam-to-column model with two-pin(wooden dowel) from the finite element method with other available theoretical and experimental rotation value.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.838-843
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• 2008

Since thickness deformation and lateral deflection often occurs during the collision of flexible bodies, they should be considered simultaneously in the impact analysis. The thickness deformation, however, cannot be considered in beam/shell theory since the thickness is assumed to be constant in the theory. So, solid elements are employed to estimate the thickness deformation. However, the CPU time increases significantly if solid elements are employed. In the present study, a modeling method for the impact analysis of a flexible body employing Hertzian contact theory is presented. The efficiency and the accuracy of the modeling method are discussed with some numerical examples.

• Magazine of the Korean Society of Agricultural Engineers
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• v.36 no.1
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• pp.103-115
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• 1994

The dynamic earthquake analysis of plane cable-stayed bridge structures was formulated and implemented into a computer program which analyzes plane cable-stayed bridge structu- res subjected to initial cable tensions, member dead and live loads and seismic loads. Cable-stayed bridges were modelled as multi-degrees of freedom systems with lumped- mass. Various earthquake responses such as dynamic deflection, bending moment, shear force and cable tension were investigated by the dynamic analyses in the form of the time history analysis. The time history analysis was based on the mode superposition method. The study revealed that Fan-l type cable-syayed bridges is generally superior to other types for the earthquake proof even though aspects of deflection and section force of each type presents respective advantages and disadvantages. The study provided a method to design the sections of cable-stayed bridges under seismic loads with various design parameters related to structural types. The study is expected to be useful for effective design of cable-stayed bridges with conside- ration of earthquake.