• Journal of Information Display
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• v.5 no.3
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• pp.18-24
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• 2004

Voltage-dependent transmittance characteristics associated with various cell parameters have been studied in-plane switching liquid crystal display when both common and pixel electrodes are transparent. When both electrodes are opaque, the transmittance is related to only the distance (I) between electrodes. However, where transparent electrode is used, it is influenced not only the 1but also an electrode width (w) and rubbing angle. In addition, these factors are related to operating voltage which shows maximal transmittance. To maximize the light efficiency of the cell and obtain low operating voltage, the above-mentioned cell parameters need to be optimized.

• Journal of KSNVE
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• v.2 no.4
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• pp.305-315
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• 1992

In order to investigate the effects of layer-wise in-plane displacements on vibration and damping characteristics of composite laminated plates, the finite element method based on the generalized laminated plate theory(GLPT) has been formulated. Specific damping capacity of each mode was obtained by modal strain energy method. To see the effect of transverse shear on deformation, the strain energy of stress components was computed. The accuracy of this study was examined for the cylindrical bending vibration of cross-ply plate strip. The results were very accurate compared with 3-D solutions. The numerical results show that through-thickness variation of in-plane displacements has not so much influence on the natural frequency, but has a great influence on the damping of composite plates, especially on the damping of thick composite plates since the damping is affected by local behavior while the natural frequency is affected by global behavior.

• Geomechanics and Engineering
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• v.12 no.6
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• pp.919-933
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• 2017

A series of Brazilian tests under diameter compression for disc specimens was carried out to investigate the strength and failure behavior by using acoustic emission (AE) and photography monitoring technique. On the basis of experimental results, load-displacement curves, AE counts, real-time crack evolution process, failure modes and strength property of granite specimens containing two pre-existing holes were analyzed in detail. Two typical types of load-displacement curves are identified, i.e., sudden instability (type I) and progressive failure (type II). In accordance with the two types of load-displacement curves, the AE events also have different responses. The present experiments on disc specimens containing two pre-existing holes under Brazilian test reveal four distinct failure modes, including diametrical splitting failure mode (mode I), one crack coalescence failure mode (mode II), two crack coalescences failure mode (mode III) and no crack coalescence failure mode (mode IV). Compared with intact granite specimen, the disc specimen containing two holes fails with lower strength, which is closely related to the bridge angle. The failure strength of pre-holed specimen first decreases and then increases with the bridge angle. Finally, a preliminary interpretation was proposed to explain the strength evolution law of granite specimen containing two holes based on the microscopic observation of fracture plane.

• Journal of the Korean Society for Nondestructive Testing
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• v.28 no.2
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• pp.211-216
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• 2008

In this study, we have developed a program which can calculate phase and group velocities, attenuation and wave structures of each mode in multi-layered plates. The wave structures of each mode are obtained, varying material properties and number of layers. The key in the success of guided wave NDE is how to optimize the mode selection scheme by minimizing energy loss when a structure is in contact with liquid. In this study, the normalized out-of-plane displacements at the surface of a free plate are used to predict the variation of modal attenuation and verily the correlation between attenuation and wave structure. It turns out that the guided wave attenuation can be efficiently obtain from the out-of-plane displacement variation of a free wave guide alleviating such mathematical difficulties in extracting complex roots for the eigenvalue problem of a liquid loaded wave guide. Through this study, the concert to optimize guided wave mode selection is accomplished to enhance sensitivity and efficiency in nondestructive evaluation for multi-layered structures.

• Steel and Composite Structures
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• v.17 no.1
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• pp.1-19
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• 2014

Buckling and vibration characteristics of circular laminated plates under in-plane edge loads and resting on Winkler-type foundation are solved by the Ritz method. Inclusive numerical data are presented for the first three eigen-frequencies as a function of in-plane load for different classical edge conditions. Moreover, the effects of fiber orientation on the natural frequencies and critical buckling loads of laminated angle-ply plates with stacking sequence of $[({\beta}/-{\beta}/{\beta}/-{\beta})]_s$, are studied. Also, selected deformation mode shapes are illustrated. The correctness of results is established using finite element software as well as by comparison with the existing results in the literature.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2001.04a
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• pp.304-311
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• 2001

Unreinforced masonry is widely used as a structural material in residential constructions and known to have poor seismic performance in the out-of-plane rather than in-plane behavior. In countries of lower seismicity such as Korea, it is necessary to check the possibility of the mode of the out-of-plane failure. Though face loading is a major cause of the failure of masonary walls, Korean Seismic Code does not include provision for face-loaded unreinforced masonry walls. This paper briefly reviews the concept of analysis for unreinforced masonry walls subjected to face-load excitation proposed by Priestley, and its applicatility to Korean case.

• International Journal of Fluid Machinery and Systems
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• v.1 no.1
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• pp.169-180
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• 2008

As a major component of a power plant, a turbine generator must have sufficient reliability. Longer blades have lower natural frequency, thereby requiring that the design of the shaft and blade takes into account the coupling of the blade vibration mode, nodal diameter k=0 and k=1 with vibration of the shaft. The present work analyzes the coupling of the translation motion of the shaft with in-plane vibration of the blades with k=1 modes. At a rotational speed ${\Omega}_1=|{\omega}_s-{\omega}_b|$, the resonance of the blades has a relatively large amplitude. A violent coupled resonance was observed at a rotational speed ${\Omega}_2=|{\omega}_s+{\omega}_b|$. Resonance in blade vibration at ${\Omega}_1=|{\omega}_s-{\omega}_b|$ was experimentally confirmed.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.10a
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• pp.45-52
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• 2001

A series of unreinforced masonry (URM) walls were analytically investigated for a limited version of seismic in-plane performance. For this URM walls were assumed to be an elastic continuum and modeled as isotropic plane stress elements within which the nature of cracking was propagated. Accordingly, cracking mode of behavior in URM was modeled by smeared-crack approach. Total of 70 cases were considered for various parameters such as axial load ratio, aspect ratio and effective section area ratio due to the existence of opening, etc. The analysis results indicated a general tendency in base shear coefficient and deformability of URM walls for these variables.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.9
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• pp.1486-1491
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• 2003

A modeling method for the modal analysis of a composite trapezoidal plate undergoing in-plane translational acceleration is presented in this paper. The equations of motion for the plate are derived and transformed into a dimensionless form. The effects of the inclination angles, fiber orientation angle and the acceleration on the modal characteristics of the plate are investigated.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.792-795
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• 2006

In-plane-switching (IPS)-mode LCD is one of the most useful technologies for a broad range of viewing angles. To apply for IPS-LCDs, we synthesized novel homogeneous alignment materials, changing dianhydrides (BTDA and BPDA) and bridged diamines (ODA and PACM). We measured their pre-tilt angles using the crystal rotation method with positive LC and their surface properties.