• 한국세라믹학회지
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• 제45권8호
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• pp.472-476
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• 2008

The surface region of commercial stainless steel 304 and 316 plates has been modified through deposition of the multi-layered coatings composed of titanium film ($0.1{\mu}m$) and gold film ($1-2{\mu}m$) by an electron beam evaporation method. XRD patterns of the stainless steel plates deposited with conductive metal films showed the peaks of the external gold film and the stainless steel substrate. Surface microstructural morphologies of the stainless steel bipolar plates modified with multi-layered coatings were observed by AFM and FE-SEM images. The stainless steel plates modified with $0.1{\mu}m$ titanium film and $1{\mu}m$ gold film showed microstructure of grains of under 100 nm diameter. The external surface of the stainless steel plates deposited with $0.1{\mu}m$ titanium film and $2{\mu}m$ gold film represented somewhat grain growth of Au grains in FE-SEM image. The electrical resistance and water contact angle of the stainless steel bipolar plates modified with multi-layered coatings were examined with the thickness of the gold film.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.589-592
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• 2009

In this paper is presenting the shape design and elastomer bearings, which functioned as a joint connecting sub-structures and upper-structures with a railway bridge bearing systems. The elastomeric spherical bearing shaped and composed of alternated 17-layered metal shim plates and 18-layered elastomer plates, respectively. The elastomeric spherical bearing a high compressive load for perpendicular axis to layered plates and flexible motions are provided coincidently for other axes. The three types of elastomers, which were developed due to a designed shear modules were applied. Nonlinear analysis based on the material properties of designed bearing were accomplished. Therefore, the Nonlinear Analysis results were compared with the calculation results and the optimized shapes were designed.

• 대한기계학회논문집
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• 제17권9호
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• pp.2252-2263
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• 1993

The purpose of this study is to verify the vibration and damping characteristics of elastic-viscoelastic-elastic structures, theoretically and experimentally. The forth-order differential equations of motion are derived for the transverse vibration of three-layered plates with viscoelastic core layer. The equations consider both transverse displacements of the constraining layer and the bare base plate as variable and account for the effect of the transverse normal strain and the shear strain of viscoelastic core layer on the vibration of the plates. Finite difference analysis of the equations and experimental measurements are performed on the three-layered plates of completely free boundary condition. Comparative investigations on the theory and the results of direct frequency analysis of NASTRAN are carried out on the same structures.

• 한국해양공학회지
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• 제19권4호
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• pp.9-14
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• 2005

In the present paper, the wave absorbing performance of the fully submerged horizontal porous plates has been investigated, numerically and experimentally. The submerged porous system is composed of multi-layered horizontal porous plates that are clamped at the vertical setwall, which are slightly inclined and placed vertically, in parallel, with spacing. The hydrodynamic interaction of incident waves with the rigid porous multi-layered plates was formulated within the context of linear wave-body interaction theory and Darcy's law. In order to validate the effectiveness of the present computing code, the numerical results were compared with the analytical and experimental results. It is found that triple horizontal porous plates with slight inclination, if properly tuned for wave energy dissipation against the standing waves in front of the vertical wall, can have high performances in reducing the reflected wave amplitudes against the incident waves over a wide range of wave frequency.

• Steel and Composite Structures
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• 제2권2호
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• pp.99-112
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• 2002

The differential quadrature method (DQM) is a numerical technique of rather recent origin, which by its continually increasing applications in different problems of engineering, is a competing alternative to the conventional numerical techniques for the solution of initial and boundary value problems. The work of this paper concerns the application of the DQM in the area of the buckling of multi layered orthotropic composite plates with various boundary conditions the buckling of multi layered composite plates with constant and variable thickness under axial compressive static loading is considered. The effects of fiber orientation and boundary conditions on static behavior of composite plates are presented. The comparison of results from the present method and those obtained from NISA II software shows the accuracy and reliability of this method.

• 대한기계학회논문집
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• 제18권7호
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• pp.1759-1772
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• 1994

In this study, we re-examined the Tate's modified Bernoulli equation to study penetration phenomena for long rod projectile into single or multi-layered finite thickness plates. We used the force equlibrium equation at mushroomed nose/target interface instead of conventional pressure equation at the stagnation point. In our penetration model, we considered the velocity dependent $R_t$ value for semi-infinite target and considered only the back face effect for finite target. To compensate for $R_t$ value according to target's thickness and back face effect, we used the spherical cavity expansion theory for semi-infinite plate and used the cylindrical cavity expansion theory for finite plate. Also we developed the experimental technique using make screen to measure the penetration duration time at each layered plate. In 3-layered laminated RHA/mild steel/ A1 7039 plate, we observed that spall had occured around the back face of A1 7039 plate by the stress wave interaction. Through the comparison between theoretical and experimental data including Lambert's results, we conform that our study has good confidences.

• 대한기계학회논문집A
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• 제31권11호
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• pp.1100-1107
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• 2007

In this study, a method to characterize material properties of adhesive that is used in a layered plates bonding process is developed by combined evaluation of experiment, simulation and optimization technique. A small bonded specimens of rectangular plate are prepared to this end, and put into a thermal loading conditions. $Moir{\acute{e}}$ interferomety is used to measure submicron displacements occurred during the process. The elevated temperature is chosen as control factors. FE analysis with constant values for the adhesive materials is also carried out to simulate the experiment. Significant differences are observed from the two results, in which the simulation predicts the monotonic increase of the bending displacement whereas the measurement shows decrease of the displacement at above $75^{\circ}C$. In order to minimize the difference of the two, material parameters of the adhesive at a number of different temperatures are posed as unknowns to be determined, and optimization is conducted. As a result, optimum material parameters are found that excellently matches the simulation and experiment, which are decreased with respect to the temperature.

• 대한기계학회논문집A
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• 제24권2호
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• pp.421-430
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• 2000

We apply the Rayleigh Ritz method to analyze multi-layered plates with residual stresses. The method is very simple, straight forward, and easily programmable, but it should be applied to structure s only in simple shapes. We derive coupled variational equations based on the principle of virtual displacement, and investigate what kind of basis functions is desirable for the analysis of rectangular plates with various boundary conditions. We demonstrate the effectiveness and usefulness of the method through several examples. The analysis results obtained with the method are in good agreement with those available in literature. A multi-layered MEMS plate example shows that the coupling effect should not be ignored and that residual stresses do influence the stiffness of the structure very much.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.836-840
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• 2006

Design optimization of layered plates bonding process is conducted to achieve high product quality by considering uncertainties in a manufacturing process. During the cooling process of the sequential sub-processes, different thermal expansion coefficients lead to residual stress and displacement. thus resulting in defects on the surface of the adherent. So robust process optimization is performed to minimize the residual stress mean and variation of the assembly while constraining the distortion as well as the instantaneous maximum stress to the allowable limits. In robust process optimization, the dimension reduction (DR) method is employed to quantify both reliability and quality of the layered plate bonding. Using this method. the average and standard deviation is estimated. Response surface is constructed using the statistical data obtained by the DRM for robust objectives and constraints. from which the optimum solution is obtained.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문초록집
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• pp.367.1-367
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• 2002

Recently, the noise environmental issue in compound residential areas like apartments becomes a very critical factor fer the building designers. In order to satisfy the customer need to live in a quiet environment, several interior structures for buildings are being introduced. The multi-layered composite floor plate is one of them. This structure is designed to prevent the noise generated by an object collision. (omitted)