• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.513-514
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• 2009

• Proceedings of the KSLP Conference
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• 2014.03a
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• pp.15-15
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• 2014

• Proceedings of the KSLP Conference
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• 2011.03a
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• pp.18-18
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• 2011

• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.349-352
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• 1987

• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.358-360
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• 1987

• Proceedings of the KSPS conference
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• 2003.05a
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• pp.196-199
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• 2003

The results of this thesis show that Seoul dialect speakers neutralized /$\varepsilon$/ and /e/ to /E/ about 80％ and the old aged generations pronounced /ㅐ/ and /ㅔ/ as it is than the young aged generations's.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.773-774
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• 2011

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.1
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• pp.64-69
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• 1999

Polyacrylonitrile(PAN)-based carbon fiber tows were heat-treated by the internal resistance heating method under the certain load. To consider the strain behavior of the fiber tows during heat-treatments, 1200~$2200^{\circ}C$, strain changes of those were measured. It was observed that the larger longitudinal strain was induced under the larger stretching stress. The changes in the strain are different from the temperature regions below and above $1700^{\circ}C$. Obtained apparent activation energies under the stretching stresses of 70 and 322 MPa from time-strain curves were 67.46 and 52.27kJ$mol^{-1}$, respectively. Therefore, it was known that the larger stretching stresses effectively reduce the apparent activation energy of the fiber structure development of the fiber tows.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.6
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• pp.1069-1076
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• 2002

The high temperature creep behavior of heat machine systems such as aircraft engines, boilers and turbines in power plants and nuclear reactor components have been considered as an important and needful fact. There are considerable research results available for the design of high temperature tube materials in power plants. However, few studies on the Initial Strain Method (ISM) capable of securing repair, maintenance, cost loss and life loss have been made. In this method, 3 long time prediction Of high temperature creep characteristics can be dramatically induced through a short time experiment. The purpose of present study is to investigate the high temperature creep lift of Udimet 720, SCM 440-STD61 and 1Cr-0.5Mo steel using the ISM. The creep test was performed at 40$0^{\circ}C$ to $700^{\circ}C$ under a pure loading. In the prediction of creep life for each materials, the equation of ISM was superior of Larson-Miller Parameter(LMP). Especially, the long time prediction of creep life was identified to improve the reliability.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.6 no.1
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• pp.24-30
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• 2000

Chitosan films were prepared using four types of chitosans with different molecular weight and the effect of molecular weight of chitosan on selected film properties such as color, water vapor permeability (WVP), water solubility (WS), tensile strength (TS), and elongation at break (E) was investigated. Generally, the total color difference (${\Delta}E$) and WS of the films decreased, while TS and E of the films increased as molecular weight of chitosan increased. WVP of the films did not show any significant relationship with molecular weight of chitosan.