• Journal of Korean Society for Atmospheric Environment
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• v.17 no.1
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• pp.75-84
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• 2001

Hot gas filtration method via using ceramic filters is an evolving technology applicable to numerous industrial and air pollution control processes. Alumino silicate, organic and inorganic binders were the major raw materials in manufacturing ceramic filters. In this work, disc type ceramic filters(50$\phi$$\times$10t) were manufactured by vacuum forming processes using ceramic raw materials. The porosity and bulk density of disc type ceramic filers ranged from 86 to 89% and from 0.27 to 0.36 g/㎤, respectively. In this work disc type ceramic medium were tested utilizing coupon experimental apparatus. Disc type filters showed high collection efficiencies over 99.96% with Darchs law coefficients of 4.1$\times$10(sup)10~9.63$\times$10(sup)10/$m^2$ depending on mean pore sizes. In addition, filtration and detachment of ceramic filters turned out to be performed effectively using 10 cm/sec face velocity, 5 minutes filtration cycle, 100msec pulse jet valve opening time and 3 bar pulsing pressure.

• Journal of Korean Neurosurgical Society
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• v.44 no.6
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• pp.382-384
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• 2008

Gas forming brain abscess is a rare disease caused by Klebsiella pneumoniae occurring in patients with impaired host defense mechanism such as diabetes mellitus or liver cirrhosis. A 59-year-old man with 2-year history of diabetes mellitus and 20-year history of liver cirrhosis presented to the hospital with headache. On the day after admission, severe headache was developed and he deteriorated rapidly. Brain CT showed a non-enhanced mass including multiple air density as well as surrounding edema seen in the right occipital lobe, and isodensity air-fluid level seen in the right lateral ventricle. Despite emergent ventricular drainage and intraventricular and intravenous administration of antibiotics, his condition progressively worsened to sepsis and to death after 5 days. Bacterial culture of blood and ventricular fluids disclosed a Gram (-) rod, Klebsiella pneumoniae. In this report we review the pathogenic mechanism and its management.

• The Journal of the Korean dental association
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• v.14 no.9
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• pp.733-737
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• 1976

The result were obtained as follow : 1. Formocresol produced the widest zone of inhibition and camphorated parachlorophenol was the next and engenol was the narrowest. 2. Formocresol revealed the most efficted forming ability of the volatile gas and camphorated parachlorophenol was the next and eugenol was the least. 3. In comparing with the weight per ml. of the tested medicaments, eugenol was 1039.99mg/ml. 4. The amount of saturation in filter paper disc camphorated parachlorophenol showed the most and eugenol showed the least.

• JSTS:Journal of Semiconductor Technology and Science
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• v.7 no.2
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• pp.82-87
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• 2007

The electrical properties of metallic junction diodes and metallic source/drain (S/D) Schottky barrier metal-oxide-semiconductor field-effect transistor (SB-MOSFET) were simulated. By using the abrupt metallic junction at the S/D region, the short-channel effects in nano-scaled MOSFET devices can be effectively suppressed. Particularly, the effects of trap states at the metal-silicide/silicon interface of S/D junction were simulated by taking into account the tail distributions and the Gaussian distributions at the silicon band edge and at the silicon midgap, respectively. As a result of device simulation, the reduction of interfacial trap states with Gaussian distribution is more important than that of interfacial trap states with tail distribution for improving the metallic junction diodes and SB-MOSFET. It is that a forming gas annealing after silicide formation significantly improved the electrical properties of metallic junction devices.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.157-158
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• 2007

Effects of post-metallization anneal (PMA) on interface trap characteristics of Si-$SiO_2$ are studied. The conventional PMA method utilizes forming gas anneal, where 10% hydrogen in nitrogen atmosphere is used. A new PMA method utilizes hydrogen rich PECVD- silicon nitride $(SiN_x)$ film as a hydrogen diffusion source and a out-diffusion blocking layer. It can be shown through charge pumping current measurement that the new PMA is indeed effective to decrease Si-$SiO_2$ interface trap density.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.585-589
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• 2007

Gas hydrate is a special kind of inclusion compound that can be formed by capturing gas molecules to water lattice in high pressure and low temperature conditions. When referred to standard conditions, $1m^3$ solid hydrates contain up to $172Nm^3$ of methane gas, depending on the pressure and temperature of production, Such large volumes make natural gas hydrates can be used to store and transport natural gas. In this study, three-phase equilibrium conditions for forming methane hydrate were theoretically obtained in aqueous single electrolyte solution containing 3wt% Nacl. The results show that Nacl acts as a inhibitor, but help gases such as ethan, propane, i-butane, and n-butane reduce the hydrate formation pressure at the same temperature.

• Journal of the Korean Ceramic Society
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• v.14 no.4
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• pp.248-255
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• 1977

The effect of firing temperature, soaking time and batch composition upon the glass phase and pore formation as well as their distribution in slag foamed glass was investigated. Sulfur dioxide gas produced by the oxidation and reduction of metal sulfide in waterslag was attributed to foam forming agent. Slag foamed glass matrix was mainly composed of 35~60% glas phase and melilite crystalline phase. The increment of bentonite addition in batch lowered the foam forming temperature in studied system. The result showed also that the foam size distribution was broadened as th firing temperature wa inbereased.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.61.1-61.1
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• 2014

IC 10 is one of the most well-known irregular starburst dwarf galaxies in the Local Group. Its low metal and oxygen abundance together with proximity make it an excellent laboratory to test star formation models, especially in low-metallicity systems like galaxies in the early Universe as well as many other local dwarfs. Among a number of active star forming regions, we have detected H2O kilo-maser emission in the south-east region of IC 10(IC 10 SE) using the Korean VLBI Network(KVN). This maser line is likely to be associated with a giant molecular cloud identified in IC 10 SE by former CO studies. Using the HI and CO data from the VLA and SMA archive, we probe the atomic and molecular gas properties of IC 10 SE. We discuss how the cool gas morphology and kinematics are related with maser and star formation activity in IC 10 SE.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.11
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• pp.1055-1061
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• 2003

A study has been made of surface modification of various organic materials by ion implantation to increase the surface electrical properties. The substrate used were PP(polypropylene), PET(polyethylene teraphthalate), ECOP(ethylene copolyester), PS(polystyrene). N$_2$, Ar ion implantation was performed at energies of 40 and 50keV with fluences from 5${\times}$ 10$\^$15/ to 7${\times}$10$\^$16/ ions/$\textrm{cm}^2$ with and without H$_2$O gas environment. Surface resistance decrease of implanted polymers was affected by ion implantation energy, ion species, atmosphere of chamber and kind of polymer. In result, surface conductivity of polymers irradiated with atmosphere gas H$_2$O was 10 times more higher than normal vacuum atmosphere, but after 90 hours, surface conductivity returned to the without H$_2$O gas atmosphere condition caused by aging effect. After vacuum forming, surface resistance value was changed to over 10$\^$16/$\Omega$/$\square$, because creation of surface cracks.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.6
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• pp.580-585
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• 2004

Silicon dioxide (SiO$_2$) is widely used as a gate dielectric material for thin film transistors (TFT) and semiconductor devices. In this paper, SiO$_2$ films were grown by APCVD(Atmospheric Pressure chemical vapor deposition) at the high temperature. Experimental investigations were carried out as a function of $O_2$ gas flow ratios from 0 to 200 1pm. This article presents the SiO$_2$ gate dielectric studies in terms of deposition rate, refrative index, FT-IR, C-V for the gate dielectric layer of thin film transistor applications. We also study defect passivation technique for improvement interface or surface properties in thin films. Our passivation technique is Forming Gas Annealing treatment. FGA acts passivation of interface and surface impurity or defects in SiO$_2$ film. We used RTP system for FGA and gained results that reduced surface fixed charge and trap density of midgap value.