• Proceedings of the IEEK Conference
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• 2000.07b
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• pp.933-936
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• 2000

N-channel poly-Si TFT, processed by Solid Phase Crystalline(SPC) on a glass substrate, has been investigated by measuring its electrical properties before and after stressing. It is observed that the threshold voltage shift due to electrical stress varies with various stress conditions. Threshold voltages measured in 1.5um and 3um poly-Si TFT’s are 3.3V, 37V respectively. With the threshold voltage shift, the degradation of transconductance and subthreshold swing is also observed.

• Journal of Ocean Engineering and Technology
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• v.7 no.2
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• pp.57-67
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• 1993

The fracture behavior of plain woven glass/epoxy composite plates with a crack is investigated under static tensile loading. It is shown in this paper that the characteristic length associated with the point stress criterion depends on the crack length. To predict the not ched tensile strength, the point stress criterion proposed by Whitney and Nuismer are modified. An excellent agreement is found between the experimental results and the analytical prediction of the modified point stress criterion. The condition of unstable crack growth in the presence of a per-existing flaw(machined notch) is examined by means of the maximum stress intensity factor $K_max$ using maximumload P$_max$. The values of $K_max$ evaluated from energy release rate G$_max$(the compliance me thod) indicate a wide difference. Therefore in regard to anisotropy and heterogeneity of the composite materials studied, the modified shape correction factor f(a/W) is obtained. $K_max$evaluated by the compliance method a little or insignificantly depends on the initial crack length a, the specimen thickness B, the crack angle .theta. and the specimen geometry.

• Journal of the Korean Ceramic Society
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• v.30 no.6
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• pp.469-477
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• 1993

Residual stresses is one of the major factors to degrade the magnetic properties of VCR magnetic heads. Vicker's indentation technique was adapted to estimate the residual stresses Residual stresses and distribution in the glass and ferrite were obtained after bonding ferrite with glass, varing the cooling rate. The compressive and tensile stresses were developed in the interface and gradually decreased with increasing distance from the interface. The stresses were decreased with a cooling rate. The mean values of residual stress in ferrite were 10MN/㎡, 8MN/㎡, 5MN/㎡ with cooling rate 10℃/min, 5℃/min, 1℃/min respectively. When the bonded sample was annealed above the glass transition temperature followed by cooling at 5℃/min cooling rate, the residual stress was reduced to 6MN/㎡.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2005.05a
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• pp.219-223
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• 2005

Nowadays laser cutting is the most promising method of cutting FPD(Flat Panel Display) glass in mass-production line. And this method can also be used to cut other brittle materials such as quartz, sapphire, ceramic and semiconductor The concept of this method is shown in picture 1. Laser beam heats glass up to strain point, not to melting point and cooling system chills glass to induce maximun thermal stress in glass surface and then the thermal stress generates micro thermal crack, in other words blind depth of crack, along laser beam and cooling line.

• Structural Engineering and Mechanics
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• v.49 no.2
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• pp.261-271
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• 2014

This paper reported an experimental study on creep behaviors of PVB and Ionoplast laminated glass (LG) under load duration of 30 days. The tests were carried out in room temperature ($23^{\circ}C$). The study revealed that after sustaining loads for 30 days, the mid-span deflection of PVB LG increased by almost 102% compared with its short term deflection, while that of Ionoplast LG approximately increased by 14%; composite effects between two glass plies in PVB LG gradually reduced with time, but did not fully vanish at the 30th day; two glass plies in Ionoplast LG on the other hand was able to withstand loads as an effective composite section during the entire loading period; the creep behaviors of both LG were not finished yet at the 30th day. In addition to this, also studied was the varying of the bending stresses of PVB and Ionoplast LG under load duration of 2 hours. The tests were carried out in ambient temperatures of $30^{\circ}C$, $50^{\circ}C$ and $80^{\circ}C$ respectively. It was found that under a given load, although the bending stresses of both LG increased with increasing temperature, for PVB LG the increasing rate of the bending stress decreased with increasing temperature, while for Ionoplast LG the increasing rate of the bending stress increased with increasing temperature.

• Journal of the Korean Society of Safety
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• v.21 no.3 s.75
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• pp.73-80
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• 2006

Generally beam design depends on the yielding and maximum strength of each member varying with its section shape. Web plate of H-shape beam has not been substituted with glass plate, because it is known that its strength and heat properties are different and it is limited to substitute the existing steel web with glass element. Ceiling height of each room should be decreased with more than 60-80cm due to the beam. Differently from this condition, glass web beam has a good point to see through it and sunshine can be penetrate into the other size especially when it is installed as of outside wall. And also, it can be safer due to controlling room inside easier, if the strength is applicate. This study is to show some applicability after finding out the properties using the test. The test members with a size of $1,600{\times}200{\times}300{\times}9mm$ being SS41 rolled steel having THK 9mm flange while having 8,10mm and reinforced glass 12mm thickness is bonded with epoxy bond under the condition of temperature $28^{\circ}C$, humidity 50%, bonding power 24Mpa. It is show reinforced glass has 5 times of fracture stress more than the common glass but $50{\sim}150%$ difference between these 2 kinds of glass was shown. Reinforce glass did not support the original upper flange after fracture but the common glass did the upper flange after unloading. Generally reinforced glass is stronger than the common one but the common glass having a part of crack on it, compared with reinforced glass having the overall fracture could be more useful in case of needing ductility.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1179-1182
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• 2005

Nowadays, CRTs are threatened by the flat panel displays (FPD). The screen quality of the CRT is one of best among the displays, however, the depth of CRTs becomes one of the most important design factor to maintain the dominated portion in the display market. When designing slim CRTs, the structure of the glass is important design factor because of the weight and safety. The stress in the glass is increased according to the shortening the total length of tube. The residual stress of the seal is also a major factor should be considered due to the large seal edge thickness. The glass design concept for Vixlim is introduced in this paper.

• Journal of the Korean Society for Railway
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• v.3 no.2
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• pp.92-99
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• 2000

Composites are very useful material for light train carbody due to its high specific strength and lightweight characteristics. The composites, called 3-D board, are developed with a special stitching method. In this process, the glass fiber fabrics of skin material and foam core material are stitched together with glass fiber thread. The glass thread in Z-axis turns into FRP form. The conventional delamination problem can be solved with 3-D sandwich structure. In addition, with the lower density of foam, the weight of the panel and the operation expenses can be highly reduced. To evaluate the usefulness of the 3-D board, the double-deck light train carbody is studied. The stress analyses are carried out under various loads and boundary conditions with FEM Code, ANSYS. On comparing with the aluminum carbody, 3-D board carbody can be reduced by about 2 ton for the total weight of carbody.

• Journal of the Korean Ceramic Society
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• v.30 no.6
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• pp.441-448
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• 1993

The Ba1-xSrxTiO3 thin films deposited on ITO-coated glass substrate at 55$0^{\circ}C$ by rf magnetron sputtering method have individual preferential orientations as a function of composition (X=0, 0.25, 0.5, 0.75, 1) due to the stress relief interactions among the intrinsic compressive stress, thermal tensile stress adn extrinsic compressive stress (compressive stress in case of BaTiO3(Tc=12$0^{\circ}C$) and Ba0.75Sr0.25TiO3(Tc=57$^{\circ}C$)). This behavior also appears on the (BaSr)TiO3 thin films (X=0.5) deposited on ITO-coated glass substrate at deposition temperature between 35$0^{\circ}C$ and 55$0^{\circ}C$. The composition of Ba1-xSrxTiO3 thin films deposited on ITO-coated glass substrate at 55$0^{\circ}C$ is close to stoichiometry (1.009~1.089 in A/B ratio), but the compositional deviation from a stoichiometry is larger as SrTiO3 is added. The morphology of Ba1-xSrxTiO3 thin films is very similar for over all substrate temperatures, and the roughness due to the differences of cluster size is the smallest at X=0.25.

• Laser Solutions
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• v.9 no.1
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• pp.9-16
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• 2006

Glass is one of brittle materials. Generally, brittle material is weak for tensile stress but strong for compression stress. Laser breaking of glass used this brittle characteristics. Laser breaking of glass was simulated to optimize breaking condition by using commercial FEM code MARC which is applicable to thermo-mechanical coupling analysis. Various shapes of heat sources were applied to the analysis and the distance between heating and cooling source were varied for each simulation. The shapes of heat sources were circle, single and double ellipse and the distance was varied from 0mm to 30mm. Moving heat sources were designed on the basis of experimental condition. As a result, double elliptic shape of heat source was the most suitable among them in laser breaking of glass. And it should be useful to determine optimal condition of laser breaking for glass.