• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.537-538
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• 2006

BSCCO thin films have been fabricated by epitaxy growth at an ultra-low growth rate. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. MgO(100) was used as a substrate. In order to appreciate stable existing region of Bi 2212 phase with temperature and ozone pressure, the substrate temperature was varied between 650 and $720^{\circ}C$ and the highly condensed ozone gas pressure ($PO_3$) in vacuum chamber was varied between $2.0{\times}10^{-6}$ and $2.3{\times}10^{-5}\;Torr$.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.83.2-83.2
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• 2019

We study the stability of the magnetic structure in active region (AR) 12371 producing an M6.5 flare on June 22 2015. We first perform a nonlinear force-free fields (NLFFFs) extrapolation to derive three-dimensional (3D) magnetic fields based on time series of observed photospheric magnetic fields. The NLFFFs well describe an observed sigmoidal structure with the shape of a double arc magnetic configuration. Next, we examine three possible instabilities (kink, torus, and double arc) to investigate how the M6.5 flare is triggered in the double arc loops. Consequently, the double arc loops are stable against kink and torus instabilities, but possibly unstable against the double arc instability before the flare occurrence. Finally, we discuss a probable scenario for the M6.5 flare.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.41.1-41.1
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• 2019

The stability analysis of coronal magnetic structures is important for studying the initiation of solar flares and eruptions. In order to understand the flare onset process, we first reconstructed the 3D coronal magnetic structures of active region 12371 with an M6.5 flare using a nonlinear force-free field (NLFFF) model based on vector magnetic fields. The NLFFFs successfully produce the observed sigmoidal structure which is composed of two branches of sheared arcade loops. The stability analysis were examined for three representative MHD instabilities: the kink, the torus, and the double arc instabilities. Our stability analysis shows that the two branches of sheared arcade loops are quite stable against the kink and torus instabilities, but unstable against the double arc instability before the flare occurrence. Finally, we discuss a probable onset process of the M6.5 flare.

• Proceedings of the SAREK Conference
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• 2006.11a
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• pp.83-83
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• 2006

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.1
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• pp.49-58
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• 1998

In this paper, a new equivalent circuit model for quantum-well laser diode (LD) is proposed. The model includes carrier transport effects in the SCH region, and rprovides, in a stable and accurate manner, large-and small-signal responses of laser diode output power as function of injected currents. SPICE simulation was performed using the circuit model and results are presented for L-I characteristics, pulse and frequency responses under various conditions. It is expencted that the new equaivalent circuit model will find useful applications for designing and analyzing OEIC, LD driver circuits, and LD packaging.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.1371-1372
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• 2010

• 한국연소학회:학술대회논문집
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• 1999.10a
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• pp.189-200
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• 1999

Combustion characteristics of a regenerative combustor for high temperature air combustion have experimentally studied. Temperature measurement on regenerative ceramic material and combustor has been carried out with changing equivalence ratio at constant turn-over period. Stable and unstable combustion region have been found and also detailed averaged temperature profile with respect to various air flow conditions have been obtained.

• 한국초전도학회:학술대회논문집
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• v.9
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• pp.237-237
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• 1999

We have observed that a stable and reproducible Negative Differential Resistance(NDR) is induced by external microwave at low power in Nb/AlO$_x$/Al/Alo$_x$/Nb junctions. To study the erratic and pozzling NDR observations we have simulated Stewart-McCumber model in the region. Experimental results and simulation results will be presented with a discussion to draw a dynamic interpreration of the NDR.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.51.3-51
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• 2001

In this paper, research of unmanned electric bicycle based on autonomic traveling is discussed. We derived dynamic equation of bicycle and introduced control theory that bicycle´s tilt angle and velocity is stable in some region. We implemented system using DSP processor, accelerometer and DC motor. Then, we carried out an experiment based on studied Control theory.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.53.6-53
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• 2002

$\textbullet$ Present a new stability analysis method of NCSs $\textbullet$ Propose the stability condition of NCSs with dynamic controller $\textbullet$ Find the stability region where NCSs for power system are guaranteed to be stable $\textbullet$ Determine a proper sampling period of NCSs that preserves desired stability performance $\textbullet$ Experiment : NCSs for power system using CAN.