• Journal of the Korean Solar Energy Society
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• v.30 no.3
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• pp.108-115
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• 2010

Global warming and heat island make the outdoor air temperature ascend. Tall office buildings are covered with glass window facades as a design aspect and the portion of window area to facade area is increasing. Hence, cooling load for solar radiation passing through glass window is rising. Cooling air to a certain room is supplied equally despite the face of the room in most office buildings. Especially, the west part of the office cannot maintain the required temperature that occupant needs because of the solar heat coming through windows.?In this study, we projected the water spray system to reduce the solar heat transfer and to reflect the solar ray through windows. We perform the experiments to evaluate the performance of the solar heat protection devices. We measured the room temperature of two separated office rooms for solar heat control devices. The investigation's results show that the water spray system is sufficient to the coated glass and the venetian blinds for the decrease of the solar heat inflow.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.2
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• pp.296-302
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• 2010

If the fiber reinforced plastic is exposed to the moisture for a long period of time, most of moisture absorption occurs on the resin place, thus dropping cohesiveness between the molecules as the water molecules permeated between high molecular chains grant high molecular mobility and flexibility. Also as the micro crack occurs due to the permeation of moisture on the interface of glass fiber and epoxy resin, it is developed to the overall damage of interface place. Hence, the study on absorption is essential as the mechanical and physical properties of fiber reinforced composites are reduced. However, the study on absorption has the inconvenience needing to expose composite materials to fresh water or seawater for 1 month or up to 1 year. Therefore, this study has exposed fiber reinforced composites to fresh water and has developed a model with an accuracy of 98% after comparing the analysis value obtained by using ANSYS while basing on the experimental value of property decline by absorption and the basic properties of glass fiber and epoxy resin used in the experiment.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.533-536
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• 2006

A light-weight aggregate with a surface layer was fabricated using glass abrasive sludge and expanding agents. The glass abrasive sludges were mixed with expanding agents ($Fe_2O_3,\;graphite,\;CaCO_3$) and formed into precursors. These precursors were sintered in the range of $700-900^{\circ}C$ for 20min. The sintered light-weight aggregate had a surface layer with smaller pores and an inner region with larger pores. The surface layer and pores controlled the water absorption ratio and physical properties. As the expanding agent fraction and the sintering temperature increased, the porosity and pore size increased. The light-weight aggregate with $Fe_2O_3$ and graphite as the expanding agents had a low water absorption ratio while the porous material with $CaCO_3$ as the expanding agent had a higher water absorption ratio and more open pores.

• Conservation Science in Museum
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• v.15
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• pp.26-37
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• 2014

The Department of Conservation Science at the National Museum of Korea carried out conservation treatment on a prized glass ewer ^{Designated as Korean National Treasure No.193} in order to enhance the ewer's structural stability and restore its true color and transparency. Prior to the conservation treatment, experiments were conducted on various materials ^{e.g., Epoxy Resin, Acrylic Resin, Photopolymer Resin, Water Glass} in order to select the most suitable materials for glass conservation. As a result, cyanoacrylate, acrylic, and photopolymer resin were found to be the most appropriate as adhesives, and acrylic resin was an appropriate restoration material. Notably, however, cyanoacrylate resin must not be used solely, and epoxy resin must be detachable.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.2
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• pp.92-98
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• 2015

The physical effect induced by acoustic cavitation was investigated to accumulate basic data for the design of ultrasonic soil washing processes using aluminum foil erosion tests. A square aluminum foil was placed on the glass beads in the pyrex vessel submerged in the sonoreactor equipped with a 36 kHz ultrasound transducer module at the bottom. Cavitational erosion of foils was quantitatively analyzed for various glass bead diameter conditions (1, 2, and 4 mm), glass bead height conditions (5, 10, 15, and 20 mm), and water height conditions (5, 10, 15, and 20 mm). It was found that aluminum foil erosion significantly increased as the glass bead diameter increased and water height over the glass bead increased due to less attenuation of ultrasound and the optimization of sound field for cavitation. Moreover mechanical mixing was suggested to move constantly particles to the bottom area where the acoustic cavitation occurs most violently. It was because aluminium foil erosion by ultrasound transmitted through glass beads was relatively too weak.

• Computers and Concrete
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• v.14 no.5
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• pp.577-597
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• 2014

This paper aims to develop a prediction model for the hardened properties of waste LCD glass that is used in concrete by analyzing a series of laboratory test results, which were obtained in our previous study. We also summarized the testing results of the hardened properties of a variety of waste LCD glass concretes and discussed the effect of factors such as the water-binder ratio (w/b), waste glass content (G) and age (t) on the concrete compressive strength, flexural strength and ultrasonic pulse velocity. This study also applied a hyperbolic function, an exponential function and a power function in a non-linear regression analysis of multiple variables and established the prediction model that could consider the effect of the water-binder ratio (w/b), waste glass content (G) and age (t) on the concrete compressive strength, flexural strength and ultrasonic pulse velocity. Compared with the testing results, the statistical analysis shows that the coefficient of determination $R^2$ and the mean absolute percentage error (MAPE) were 0.93-0.96 and 5.4-8.4% for the compressive strength, 0.83-0.89 and 8.9-12.2% for the flexural strength and 0.87-0.89 and 1.8-2.2% for the ultrasonic pulse velocity, respectively. The proposed models are highly accurate in predicting the compressive strength, flexural strength and ultrasonic pulse velocity of waste LCD glass concrete. However, with other ranges of mixture parameters, the predicted models must be further studied.

• Progress in Medical Physics
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• v.24 no.3
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• pp.140-144
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• 2013

In this research, the glass dosimeter was calibrated to measure the standard absorbed dose of the Cs-137 irradiator and absorbed dose in a biological sample. Absorbed dose in water for Cs-137 gamma ray was determined by the IAEA TRS-277 protocol. The PTW-TM30013 ion chamber and the PTW-TM41023 water phantom were utilized for measuring absorbed dose and the value was compared with the reading from DoseAce GD-302M glass dosimeter from Asahi Techno Glass Corporation for its calibration. The uncertainty of measurement ($1{\sigma}$) of the calibrated glass dosimeter was 2.7% and this result would be applied to improve the accuracy in measurement of absorbed dose in a biological sample.

• Journal of the Korean institute of surface engineering
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• v.46 no.4
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• pp.162-167
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• 2013

Encapsulation is required since organic materials used in OLED devices are fragile to water vapor and oxygen. Laser sealing method is currently used where IR laser is scanned along the glass-frit coated lines. Laser method is, however, not suitable to encapsulating large-sized glass substrate due to the nature of sequential scanning. In this work we propose a new method of encapsulation using Joule heating. Conductive layer is patterned along the sealing lines on which the glass frit is screen printed and sintered. Electric field is then applied to the conductive layer resulting in bonding both the panel glass and the encapsulation glass by melting glass-frit. In order to obtain uniform bonding the temperature of a conductive layer having a shape of closed loop should be uniform. In this work we conducted simulation for heat distribution according to the structure of a conductive layer used as a Joule-heat source. Uniform temperature was obtained with an error of 5% by optimizing the structure of a conductive layer. Based on the results of thermal simulations we concluded that Joule-heating induced encapsulation would be a good candidate for encapsulation method especially for large area glass substrate.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.9
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• pp.571-576
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• 2015

In this study, we developed a lead-free $P_2O_5-V_2O_5-ZnO$ glass frit for sealing OLED using laser irradiation. The frit satisfied the characteristics required for laser sealing such as low glass transition temperature, low coefficient of thermal expansion (CTE), high water-resistance, and high absorption at the wavelength of the laser beam. Ceramic fillers were added to the glass frit in order to further reduce and match its CTE with that of the commercial glass substrate. The addition of Zirconium Tungsten Phosphate (ZWP) to the frit yielded the most desirable results, reducing the CTE to $45.4{\times}10^{-7}/^{\circ}C$, which is very close to that of the glass substrate ($44.0{\times}10^{-7}/^{\circ}C$). Successful formation of a solid sealing layer was observed by optical and scanning electron microscopy.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.326-326
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• 2007

Influence of $Nd_2O_3$ addition to $ZnO-B_2O_3$-based glass on the water leaching resistance of the glass was first investigated. The optimized $Nd_2O_3-ZnO-B_2O_3$ (NZB) glass was ball milled for varying time, mixing with followed by $Al_2O_3$ crystalline phase to form $Al_2O_3$-NZB glass composites at $875^{\circ}C$ for 1h. Microwave dielectric properties of the composites were investigated as a function of the ball milling time of the NZB glass. Dielectric constant and quality factor were 5.70 and 9497 GHz, respectively, when the NZB glass was ball milled for 6h prior to mixing with $Al_2O_3$.