• Journal of the Korean Vacuum Society
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• v.16 no.5
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• pp.353-358
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• 2007

J-shaped superluminescent diodes (SLD) utilizing trench structure have been fabricated on the multiple quantum dots epi-structure with its ground state energy wavelength of $1.3\;{\mu}m$. It was observed that optical power was drastically increased up to 20 times in comparison with that of SLD without trench structure, The electroluminescence characteristics showed that the peak intensity of excited state was several ten times higher in the SLD with trench than without trench structure. It is explained that the optical power enhancement of J-shaped SLD with trench structure resulted from the drastic increase of peak intensity of excited state.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.12
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• pp.6373-6386
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• 2013

This study examined the relationship between the MBTI character types and heart rate variability. The subjects were 25 students in the department of emergency medical technology in C city, Chungnam, Korea. The heart rate variability was measured under two conditions: a stable state, and in the second week and fourth week in clinical practice. The period of the heart rate variability measurements was from Jun. 21, 2013 to Jul. 26, 2013.The changes in the HRV at the stable state and during clinical practice depending on the MBTI character types, and the HRV at the stable state and during clinical practice according to the distribution chart of four character types showed a significant difference in the nHF and standard deviation of all R-R intervals (SDNN). In the changes in the HRV at the stable state and during clinical practice depending on the preference distribution chart of each indicator, the T-F group and J-P group in the nLF, T-F group and J-P group in the nHF, S-N group in the standard deviation of all R-R intervals (SDNN) and the J-P group in the mHR showed a significant difference.

• Journal of the Korean Vacuum Society
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• v.18 no.4
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• pp.266-271
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• 2009

We have investigated the lasing characteristics of GaAs-based 1300 nm wavelength region InAs Quantum Dot Laser Diode grown by Migration Enhanced Molecular Beam Epitaxy. Under a pulsed and CW operation, we observed the state switching of lasing wavelength from ground state (1302 nm) to excited state (1206 nm) due to the gain saturation of ground state. Under a pulsed operation, $J_{th}=92A/cm^2$, $\lambda_L=1311\;nm$ and under a CW operation, $J_{th}=247A/cm^2$, $\lambda_L=1320\;nm$.

• Bulletin of the Korean Mathematical Society
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• v.12 no.1
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• pp.5-6
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• 1975

• Proceedings of the Korean Nutrition Society Conference
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• 1999.05b
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• pp.53-53
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• 1999

• Kyungpook Mathematical Journal
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• v.26 no.1
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• pp.11-22
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• 1986

• Kyungpook Mathematical Journal
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• v.31 no.2
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• pp.143-150
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• 1991

• Kyungpook Mathematical Journal
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• v.19 no.1
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• pp.3-7
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• 1979

• Computational Structural Engineering
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• v.14 no.3
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• pp.41-47
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• 2001

• Carbon letters
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• v.10 no.2
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• pp.94-96
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• 2009

[ $C_f/C-Cu$ ]composites were fabricated by infiltrating molten Cu into different $C_f/C$ preforms prepared by chemical vapor infiltration, resin impregnation and carbonization. The microstructure and properties of the composites were investigated. The results show that Cu in the composites filled the pores and showed network-like distribution. Compared with homemade J204 brush material and certain grade pantograph slider from abroad, the composites have higher flexural strength and better electrical conductivity. The friction and wear properties of the composites are better than that of J204, and closed to that of the abroad material.