• Journal of the Korean Society of Safety
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• v.22 no.4
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• pp.26-31
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• 2007

According to the statistical analysis on the electrical fire of 2005 years, most of electrical fire is generated from short circuit(4,985 cases), overcurrent(755 cases) leakage current(391 cases), poor contact(378 cases), disconnection(36 cases) on the electrical wiring device. The researches for the fire hazard about normal electric wiring have already been progressing in the advanced country such as USA and Japan, but Comparative study of the disconnection has not been conducted. Therefore, in this paper, we have simulated the thermal analysis for electrical wire according to deteriorating time in a normal state and disconnection with electrical wire using the electrical-thermal finite element method(Flux 3D). This paper acquire basis data of electricity fire signal by disconnection and wish to help for electrical fire cause diagnosis business.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.417-421
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• 2003

The purpose of this paper is to study on the construction of roadbed with environmental friendly soil amendment agent. The special amendment agent used in this study is mainly composed of inorganic metal salts such as sodium chloride, magnesium chloride, potassium chloride, calcium chloride,, thus is friendly to the environment, and has a function of soil-cement-agent solidification. Various components of this agent weaken the negative function of humic acid and decompose humic acid itself. Then, the calcium cation of the cement can now be made contact directly to the soil surface. The project of local road demonstration of roadbed construction with special soil treatment agent was peformed in Northeast Thailand on August 1999 by the sponsor of Highway Department of Thailand. A series of field experiments including unconfined compressive strength were carried out to investigate the physical and mechanical characteristics of solidified roadbed treated by this solidifying agent. The results of this research showed that the roadbed using poor soil could be efficiently constructed by treatment of this amendment agent.

• Journal of the Korean Home Economics Association
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• v.41 no.5
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• pp.131-148
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• 2003

This study investigated family foster care characteristics according to types of foster parents-surrogate, kin, general parents and predicting factors of foster children's adjustability to new environment. Participants were 618 cases of foster parents in 17 areas of the country through stratified sampling. It was found that the surrogate foster parent, tends to be older, received less education, has lower income, and is in poor health, as opposed to kin parents or general foster parents. There were significant effects of foster parent's age, living arrangement, income, education, consideration of foster child, and the periods of foster care experience as well as child's sex, contact of biological parents on emotional, behavioral, and family relational adjustment of the foster children.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2002.11a
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• pp.36-46
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• 2002

The accurate characterization of paper structure may provide critical information for ideal selection of raw materials and papermaking processes as well as for predicting the behavior and the quality of final paper products. In this study, local paper structure and the relationship among the structural parameters, thickness, grammage, apparent density and surface roughness of various handsheet and commercial paper samples were evaluated by using recently developed methods. A new concept of surface roughness was also introduced. The results demonstrate that there is significant overestimation in the measured thickness when using the conventional caliper method that originates from the surface roughness and poor paper formation. A novel non-contact thickness tester, referred to as the twin laser profilometer(TLP), provided results that were not subject to these artifacts and thus provided the local intrinsic thickness and consequently the local intrinsic apparent density.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.2130-2131
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• 2011

Electric fire breaks out by various causes such as electric short, overload(over current), leakage current, poor contact, static electricity, insulation deterioration, partial disconnection and etc. In this paper, we studied analysis technique for scientific and systematic judgment for distinction of electricity fire existence and nonexistence, and described about electricity fire cause analysis process for collecting physical evidences. We handled external form analysis, Substance extension analysis, X-ray transmission analysis, cross-section analysis, thermal analysis, chemical structure analysis, surface structure analysis, component analysis, electrical properties analysis, and circuit analysis by analysis technique for electricity fire cause judgment. We expect that analysis technic elevation and correct cause of fire analysis of scene of a fire investigators and analysts through this paper which see help.

• BMB Reports
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• v.30 no.6
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• pp.385-389
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• 1997

Many cell types are known to stimulate $CD8^+$ T cells in allogeneic recognition such as mixed lymphocyte reaction (MLR). Whereas dendritic cells are most potent among them. T cells are usually considered very poor in stimulating $CD8^+$ T cells although there are some tumor cells that are weakly stimulatory. T cells, as a stimulator, cultured in the presence of concanavalin A that were otherwise nonstimulatory to $CD8^+$ T cells appeared to stimulate $CD8^+$ T cells strongly when they were pretreated with neuraminidase. The enhancement of MLR by neuraminidase could be achieved by treating either the stimulators or responders with neuraminidase. Removal of negatively-charged sialic acid moieties from the cell surface, which reduced electrostatic repulsion between responders and stimulators to give better cell-cell contact might be responsible for the enhanced MLR. In addition, neuraminidase treatment also appeared to deliver activation signal to responding T cells since it could activate $CD8^+$ T cells in synergy with phorbol myristate acetate. The maximal responses were observed when both responders and stimulators were treated with neuraminidase.

• Proceedings of the IEEK Conference
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• 2001.06b
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• pp.185-188
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• 2001

In this study, $Al_2$O$_3$films have been deposited with Atomic Layer Deposition(ALD) for gate insulator for MPTMA and $H_2O$ at low temperature below 40$0^{\circ}C$ . Conventional methods of $Al_2$O$_3$thin film deposition have suffered from the poor step coverage due to reduction of device dimension and increasing contact/via hole aspect ratio. ALD is a self-limiting growth process with controlled surface reaction where the growth rate is only dependent on the number of growth cycle and the lattice parameter of materials. ALD growth process has many advantages including accurate thickness control, large area and large batch capability, good uniformity, and pinholes freeness.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.4 s.112
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• pp.52-59
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• 2005

Most of printing paper market today have been occupied by western paper and some machine-made Hanji used don't show the characteristic advantages for traditional hand-made Hanji. Although hand-made Hanji has an aesthetic and qualitative value, it has limited uses because of poor printability as printing paper. Unlike western paper, conventional Hanji cannot be used as Printing paper because it is impossible to make the clear formation of printed dot and to develop a high level of sizing and picking problem occurs during printing. Improvements of physical and optical properties such as roughness, smoothness, air permeability, contact angle, opacity, and paper gloss as well as sizing level were accomplished through internal and surface sizing and calendering, which made the paper better suited for printing and decreased problems during printing.

• Tribology and Lubricants
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• v.27 no.1
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• pp.25-33
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• 2011

Rolling contact ball bearings are utilized almost exclusively for liquid propellant rocket engine turbopump. Turbopump ball bearings are required to endure high speed and high load for a poor lubricated condition in cryogenic environment. To evaluate bearing heat generation performance, friction torque is investigated as a function of rotation speed, bearing load and cooling flow rate through an experimental study using water coolants. Radial and axial loads are simultaneously applied to the test bearing by gas pressurized cylinder rod. Endurance performance of bearing has been also verified under the bearing required load for operating condition during total accumulated test time 2,100 sec.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.11a
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• pp.48-51
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• 2011

본 논문은 나사조임 단자대 내에 접속되는 전선의 접촉불량에 따른 발열특성을 분석하고자 단자대 접속개소의 조임토크를 KS C 2625에서 규정한 정상조임토크와 인위적인 불량조임토크를 변수로 설정하여 조임토크의 크기별로 동일한 부하를 인가한 후, 열화상카메라를 이용하여 접속불량에 따른 발열특성을 비교 분석하였다.