• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.511-516
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• 2013

The thickness and deflection of melting parts of the glass edge reach the biggest effect on the intensity and thermal insulation performance. During the sealing process using a hydrogen mixed gas torch, the thickness and the deflection effect of the edge part are affected by process parameters. In order to analyze the correlative relationship of the thickness prediction and the deflection of the edge part according to the process parameters, data was obtained by conducting sealing experiments. The main effects and interaction effects of process parameters for the thickness and the shape of the glass edge parts were analyzed through the design of experiment. A mathematical experiment equation that can predict the thickness and deflection of the edge part according to the process parameters was developed by conducting multiple regression equations.

• The Journal of the Korea Contents Association
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• v.18 no.10
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• pp.596-607
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• 2018

The purpose of this study was to review the relationships among parental care and parental overprotection perceived by adolescence, their ego-resilience and self-regulated learning ability. For this purpose, a total 2,002 students were selected from the seventh data sets of the Korean Child and Youth Panel Survey(KCYPS). More specifically, samples were composed of 1st graders in middle schools(n=2,002). As a result, first, the perceived parental care had significant effects on the self-regulated learning ability both directly and indirectly through ego-resilience. Second, the perceived parental overprotection had effects on their self-regulated learning ability mediated by ego-resilience. But the effect of parental overprotection was less than the effect of parental care. This study implies that parental care attitude and ego-resilience play important roles in the continuous development of adolescents' self-regulated learning ability.

• Composites Research
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• v.27 no.3
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• pp.96-102
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• 2014

In this study, we fabricated jute fiber reinforced polylactic acid (PLA) composite in the form of sandwich panel structure which includes core foam of chopped jute fiber reinforced PLA and outer skin layer of continuous glass fiber reinforced PLA. Flexural properties of the composite were assessed for different jute fiber weight fractions. Density of the core foam ranged from 0.31 to 0.67 $g/cm^3$ and void content fraction 0.51 to 0.71. The maximum flexural strength was 92.7 MPa at 12.5 wt.% of jute fiber content, and the maximum flexural modulus was 7.58 GPa at 30.0 wt.%. Cost analysis was also conducted. The cost to enhance the flexural strength of the applied structure was estimated to be $0.010USD/m^3/MPa$ for 12.5 wt.% fiber content.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.487-487
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• 2012

플라즈마 디스플레이 패널(PDP)은 공정 절차가 간단하고 가격 경쟁력이 매우 뛰어나 일찌감치 대형 평판 디스플레이 시장을 주도해 왔으며 빠른 응답 속도를 기반으로 한 생생한 화질의 구현으로 3D TV 시장에서도 꾸준한 사랑을 받고 있다. 향후 더 큰 화면을 요구하는 PID(Public Information Display) 시장에서도 PDP 는 두각을 나타낼 수 있을 것으로 보인다. 하지만 PDP 는 여전히 LCD, OLED 등의 디스플레이에 비해 발광 효율이 낮고 소비 전력이 높다는 단점을 가지고 있다. 또한 미국 환경청(EPA)과 에너지부(DOE)가 공동으로 마련한 전자 제품의 효율 등급제인 에너지 스타(Energy Star) 제도가 끊임없이 개편되면서 소비 전력에 대한 규제가 점차 강화되고 있기 때문에 발광 효율 및 소비 전력 특성의 개선은 현재 PDP 업계가 해결해야 할 가장 중요한 과제라고 할 수 있다. 발광 효율의 개선과 관련하여 최근에는 PDP의 보호막으로 널리 쓰이고 있는 MgO 보다 2차 전자 방출 계수가 높아 PDP의 구동 전압을 낮추는 동시에 휘도와 발광 효율 특성을 개선시킬 수 있는 신 보호막에 대한 연구가 활발히 이루어지고 있다. MgO를 대체 가능한 신 보호막으로 언급되는 물질은 SrO 혹은 CaO 등이 대표적이다. 하지만 이러한 물질들은 공기 및 수분에 대한 용해도가 높기 때문에 증착된 막이 이후의 공정 과정(합착 및 가열 배기 등)에서 대기 중에 노출 될 경우 심하게 변질될 수 있다. 이러한 문제점을 해결하기 위해서 신 보호막 위에 기존의 MgO 보호막을 얇게 증착하여 공기로부터의 접촉을 차단하거나 펠렛을 제조하는 과정에서 MgO 에 신 보호막 물질을 소량만 첨가하는 등의 방법들이 제안되어 왔으며 그 결과 기존의 PDP 대비 구동 전압을 낮추고 발광 효율을 획기적으로 개선하는데 성공한 결과들이 지속적으로 보고되고 있다. 하지만 신 보호막이 공기 및 수분에 민감한 만큼, 고온의 공정으로 인해 PDP의 하판 유리로부터 상판에 증착된 박막으로 확산되는 불순물에 의해서도 오염되며 이 역시 신 보호막의 특성을 구현하는데 방해 요소로 작용한다. 본 연구에서는 PDP 하판의 불순물이 상판의 박막으로 확산되는 것을 방지하고자 하판 형광체 인쇄전 PECVD 증착법으로 확산 방지막을 1 가량 형성하였다. 이후 SIMS 분석을 통하여 하판 불순물의 확산이 효과적으로 차단됨을 확인하였고 신 보호막의 오염을 최소화하여 결과적으로 PDP의 구동 전압을 낮추고 효율을 획기적으로 개선하는데 기여할 수 있음을 확인하였다.

• Applied Chemistry for Engineering
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• v.10 no.8
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• pp.1114-1118
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• 1999

Barrier rib for the plasma display panel(PDP) was made by photolithographic process utilizing photosensitive barrier rib paste. The barrier rib paste was prepared by first dissolving ethylcellulose(binder polymer) in butyl carbitol(BC)/butyl carbitol acetate(BCA) =30/70 wt % mixture solvent at 15 wt % concentration. To this solution a mixture of functional monomers consisted of tripropyleneglycol diacrylate/ pentaerythritol triacrylate = 50/50 wt %, Irgacur 651 photoinitiator, and barrier rib powder were added and then the whole mixture was mixed in the three roll mill for 2 hr. The effect of component and concentration of photosensitive barrier paste on the photolithographic process was studied. After optimization of the paste formulation and photolithographic process, barrier rib could be obtained with good resolution up to $100{\mu}m$ height.

• Journal of the Korean Vacuum Society
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• v.9 no.3
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• pp.237-241
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• 2000

The structural, electrical and etching characteristics of Al alloy thin film with low impurity concentrations AlNd deposited by using do magnetron sputtering deposition are investigated for the applications as gate bus line in the TFt-LCD panel. And ITO thin film was deposited on AlNd, then the contact resistance was measured by Kelvin resistor. The deposited thin films show the decrease of resistivity and the increase of grain size after the RTA at $300^{\circ}C$ for 20 min. Moreover, the resistivity of AlNd does not show appreciable grain size dependence after RTA. It is concluded that the decrease of resistivity after RTA is due to the increase of grain size. The annealed AlNd is found to be hillock free. The etching profiles of AlNd was good and the minimun contact resistance was about $110\;{\mu\Omega}cm$. Calculation results reveal that the AlNd (2wt.%) thin film can be applicable to 25" SXGA class TFT-LCD panels.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.4
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• pp.651-656
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• 2019

This paper is a study on the structure system and implementation of cantilever actuator for decontamination. There are many kinds of exterior materials that attach to the exterior walls of a building. Glass, in particular, can be contaminated in a short period of time due to external exposure. The pollutants like this damage the appearance of a building. It can also cause health problems for users, and dust attached to solar panels creates problems that greatly reduce the power generation of solar panels. In order to remove such contaminants, professional workers usually remove contaminants attached to the outer walls. However, even with stability, accidents are often caused by a number of unexpected variables that occur in the field. Thus, to overcome these shortcomings, the cantilever actuator structure system was proposed. The system was designed through research. Then, we made a cantilever actuator and checked its operability. Finally, the effectiveness of the cantilever actuator was reviewed.

• International Area Studies Review
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• v.14 no.2
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• pp.251-272
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• 2010

This study was done through Panel Gravity Model to analyze the trade pattern of Korean motor industry and empirical analysis was also performed on the effect of regional economies joining to the Korean trade is to draw out some implications. Compared with per capita pattern regarding the income levels of both the countries, the results indicated that trade of Korean motor industry followed GDP pattern in accordance with the overall market. The results of effect on regional economic integration to Korean motor industry reflected 179% and 198% increase in motor trade industry and motor parts trade, respectively. To expand the trade of Korean motor industry at the international competitiveness level, focus should be made on smaller, smarter and greener car with lesser impact on the environment. Hence, the present investigation suggested that government should not delay in retaining the core technology as well as private sector should also aggressively invest in the market.

• Composites Research
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• v.20 no.6
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• pp.8-14
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• 2007

Debonding failure characteristics of the composite skin-stiffener specimens were experimentally investigated. The influences of bonding methods, types of stiffener shape and various secondary bonding parameters were evaluated. Present test results combined with the previous test results[1] showed that the failure displacement of the skin-stiffener specimens well evaluates the skin-stiffener debonding failure strength of the composite stiffened panels. The specimens with an open type stiffener had lower bending stiffness and larger failure displacement than those with a closed type stiffener. Secondary bonding and co-curing with adhesive had better failure strength than co-curing without adhesive film. Secondary bonded specimens failed by adhesive failure and co-cured specimens failed by delamination failure. As the bondline thickness was thinner, the skin-stiffener specimens had higher failure strength. The fillets had no influence on failure strength of the specimens. The influence of the surface roughness was shown according to types of stiffener shape.

• Journal of the Korean Applied Science and Technology
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• v.34 no.1
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• pp.152-162
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• 2017

A hydrophilic coating solution was prepared by adding a silane coupling agent and a nano-inorganic oxide in aqueous surfactant solution to increase the efficiency of photovoltaic power generation due to the introduction of antifogging and antifouling properties on the glass surface of the solar cell module. Addition of $Ludox^{(R)}$, a nano-inorganic oxide, to 1% hydrophilic coating solution showed improved hydrophilicity and excellent antifogging effect regardless of $Ludox^{(R)}$ concentration. However, the antifouling effect on the glass surface was showed only when Ludox was added more than 10%. In the case of addition of 0.7% of hydrolyzed TEOS at pH 4, the antifogging effect was maintained as a result of the steam test as well as the antifouling effect even after the coated glass surface was rubbed 100 times with a wet Kimwipe. In addition, from the surface roughness ($R_q$) calculated using AFM data, the higher surface roughness with irregular surface shape was obtained with the higher concentration of TEOS. The addition of 0.7% of TEOS showed relatively high surface roughness and well organized surface condition which can help to improve transmittance of light. In conclusion, $Ludox^{(R)}$ is not required only for the antifogging property. However, at least 10% of Ludox should be added to show antifouling effect and 0.7% of TEOS should be added for good durability.