• Structural Engineering and Mechanics
• /
• v.63 no.2
• /
• pp.217-223
• /
• 2017

Glass fiber reinforced gypsum panels (GFRG) are hollow panels made from modified gypsum plaster and reinforced with chopped glass fibers. The hollow cores of panels can be filled with in-situ concrete/reinforced concrete or insulation material to increase the structural strength or the thermal insulation, respectively. GFRG panels are unfilled when used as partition walls. As load bearing walls, the panels are filled with M 20 grade concrete (reinforced concrete filling) in order to resist the gravity and lateral loads. The study was conducted in two stages: First stage involves formulation of the alternate light weight mix by conducting experimental investigations to obtain the optimum combination of phosphogypsum and shredded thermocol. In the second stage the alternate mixes are filled in GFRG panels and experimental investigations are conducted to compare the performance against panels filled with conventional M 20 mix.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.8 no.4
• /
• pp.28-33
• /
• 2009

Yoke is a part of rotor in unmanned helicopter. It was transferred power of engine to the rotor. It has been usually produced by machining and used wastefully material. And it has been considered to improve its proof stress against repeated loading of the products. Therefore we studied Forging process for satisfaction of these ability and process design for yoke forming has been studied by using FE analysis. Die design and forming analysis have been performed according to the conditions such as billet volume, flash control, cavity filling, and the distribution of damage in the products. In the comparison between die forging processes, side punch effects has been investigated by considering billet dimensions.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2002.08a
• /
• pp.500-503
• /
• 2002

In this paper, we demonstrate the deformation of TFT-LCD panel using numerical analysis based on the finite element method. To make better uniform cell gap and less stress at a photo-definable spacer (spacer), we have investigated process and design factors such as amount of liquid crystal (LC), spacer density, area, height, and material property. Furthermore we optimized design factors and achieved the robust design through the simulation.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1996.11a
• /
• pp.182-186
• /
• 1996

In this work, a method is described to investigate the progressive and compound process in the coining and piercing operation for given conditions and parameters, using the FEM simulation and model experiment. The effect of the die shape on the compound process is established, and the die shape depends on the position of coining die and the width of the part coined. It is found that Progressive process is better than compound process, since material's filling into the die is not completed and the higher stress acts on the edge of the punch according to width being increased.

• Transactions of Materials Processing
• /
• v.16 no.4 s.94
• /
• pp.271-275
• /
• 2007

These days, recycling of plastic material has become a major issue due to the landfills and environmental problem. This study investigates the fluidity of thermoplastic vulcanizate(TPV), which can be used for an automobile part such as a weather strip, in order to replace ethylene propylene rubber(EPDM). Injection molding experiments with the spiral flow test mold and panel cover mold are conducted to examine the fluidity of TPV during injection molding. It is found out that the recycled TPV's flow length is a little bit longer than the virgin TPV. However, the filling weight for a panel cover parts by a recycled TPV is almost the same as that by a virgin TPV.

• Journal of Korea Foundry Society
• /
• v.23 no.1
• /
• pp.47-51
• /
• 2003

This experimental study was carried out to investigate the solidification characteristics of polystyrene added styronaphthalene pattern materials using various castability test methods. The styronaphthalene showed an excellent filling capacity and shaping behavior having about 0.2 mm meniscus radius. The shell thickness of styronaphthalene showing smooth wall at the solid/liquid interface increased with the increasing of polystyrene addition. The solidification microstructure of styronaphthalene showed a typical thin ribbon reinforced composite structure, which has fibrous amorphous skeleton of polystyrene and crystalline naphthalene. From the results of this study, it was found that the polystyrene added styronaphthalene showed a precision shaping behavior as disposable pattern material under the atmospheric condition.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2009.03a
• /
• pp.912-921
• /
• 2009

Pulse-discharge technology (PDT) is an innovative technology which uses enormous energy developed by electric discharge for a very instant moment of time. Lately, it has been applied to make expanded sections at the ends of piles and anchors. The expanded section is formed by the deformation of bore-hole induced by shockwave energy developed in filling material by the pulse discharge. In this study, considering the phenomenon of pulse-discharge as an underwater explosion, finite element analyses were carried out to model the shockwave development by pulse discharge. The simulation technique was verified by comparing results with underwater discharge test results.

• Ceramist
• /
• v.22 no.1
• /
• pp.17-26
• /
• 2019

The metal-to-insulator transition (MIT) with external stimuli is one of the main issues in correlated oxides. The physical properties are extremely sensitive to band filling, because the MIT is attributed to the strong correlation between electrons in narrow d-band. Since hydrogen is the smallest and lightest element, it is not only likely to doped reversibly in oxides, but also acts as a dopant to provide electrons. The correlated oxides showing MIT are structurally expanded after hydrogenation, and their electrical properties are drastically changed. Researches on this phenomenon have been actively carried out to date. They are of great scientific importance, and the use of this material is very diverse, including the development of next-generation hydrogen sensor, or hydrogen-based neuromorphic devices.

• Journal of Electrochemical Science and Technology
• /
• v.8 no.2
• /
• pp.146-154
• /
• 2017

In this study, copper (II) oxide was prepared for use in a copper electroplating solution. Copper chloride powder and copper (II) oxide are widely used as raw materials for electroplating. Copper (II) oxide was synthesized in this study using a two-step chemical reaction. Herein, we developed a method for the preparation of copper (II) oxide without the use of sintering. In the first step, copper carbonate was prepared without sintering, and then copper (II) oxide was synthesized without sintering using sodium hydroxide. The optimum amount of sodium hydroxide used for this process was 120 g and the optimum reaction temperature was $120^{\circ}C$ regardless of the starting material.

• Proceedings of the KIEE Conference
• /
• 1999.07e
• /
• pp.2453-2455
• /
• 1999

We propose that we use a porous-Si for a new spatial walk-off polarizing material with a large split angle. The beam-split an91e f is determined by the filling factor g(or porosity p) of the columnar dielectric substance and the slant angle $\theta$. Theoretically, by the assuming that $n_2$=3.5, and $n_1$=1 one can predict that a large split angle, up to $27^{\circ}$, is possible if one can construct such films with $Si.^{[3]}$ To accomplish this, we use porous-Si. As a result of theoretical simulation, the best structural parameters for attaining the maximum split angle $\phi$=$27.5^{\circ}$ are $\theta$=$58.7^{\circ}$ and p=57.6%.