• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05b
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• pp.60-64
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• 2005

Discharge of the flat lamp lighting source research are requested very much. For improving brightness, life time, efficiency of flat lamp, plasma diagnosis of the flat lamp lighting source to understand property of lighting source is very important, distance of discharge electrode is 5.5mm and width is 16.5mm, we measured electron temperature and electron density measured with single langmuir probe in flat lamp, we tested the discharge from 100 Torr to 300 Torr pressure, the Pulse is rectangular pulse with frequency 20kHz and Duty ratio 20%. Resultly, electron temperature decreases and electron density increase as increase the gas pressure and electron temperature decreases and electron density increase as increase the voltage.

• The Bulletin of The Korean Astronomical Society
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• v.34 no.1
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• pp.71.1-71.1
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• 2009

• Bulletin of the Korean Space Science Society
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• 2009.04a
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• pp.57.1-57.1
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• 2009

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.79.2-79.2
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• 2015

The $M_{BH}-{\sigma}$ relation for galaxies is a stand-out illustration of the co-evolution of galaxies and their central supermassive black holes (SMBHs); however, how this co-evolution occurs and whether this relation holds for SMBHs of the early universe is still a matter of debate. In order to study this at higher redshifts, quasi-stellar objects (QSOs) are the best targets, due to their large sample size and effective $M_{BH}$ estimation. Nevertheless, it is difficult to examine properties of their host galaxies, simply due to the sheer brightness of the QSO itself. Here, we discuss a distinctive method in studying these QSO host galaxies, via gravitational lensing (GL). GL offers a unique approach in determining the mass of the lens object, in this case the host galaxy. QSOs from the SDSS quasar catalog were searched in the Hubble Space Telescope archives, and GL features around them were visually inspected. One such candidate is SDSS J1114-00; to increase its robustness as a GL system candidate, it was observed with the Inamori-Magellan Areal Camera & Spectrograph (IMACS) on the Magellan Baade Telescope at Las Campanas Observatory, to check whether the GL features have identical colors, meaning they are likely to originate from the same source. After confirmation of such GL systems, a sufficiently large sample will enable us to examine the $M_{BH}-{\sigma}$ relation at various redshifts, and in turn, investigate the co-evolution of SMBHs and their host galaxies.

• Journal of Sasang Constitutional Medicine
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• v.16 no.1
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• pp.20-36
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• 2004

After studying the theory of JangBu(臟腑), that is a physiology of Sasang Constitutional Medicine, in Sasang Constitutional Medicine, the author could draw a conclusion as these. 1. The basic thought of Sasang Constitutional Medicine is emphatic on the human beings itself unlike the idea of traditional Oriental Medicine, that accentuate the universe.(The traditional Oriental Medicine has a concept that the human beings follows the order of universe, but Sasang Constitutional Medicine has a different idea that human beings has the free will to the universe and newly comprehend the relationships between human beings and universe.) 2. Like the preceding, the theory of JangBu(臟腑), the physiology of Sasang Constitutional Medicine, is based on the autonomic mechanisms of human body itself. 3. The medical philosophy of Sasang Constitutional Medicine is Sasang(四象), that is Sa(事), Sim(心), Sin(身) and Mul(物). This Sasang is a classification of universe include human beings.(Sa(事) is event, Sim(心) is mind, Sin(身) is body, and Mul(物) is things. these four elements express the universe and human.) 4. The JangBu(臟腑) theory of Sasang Constitutional Medicine regard mind condition as important. The mind condition is divided into two factors. The one is Seong(性) the other is Jeong(情). The Seong(性) is an attitude toward the world, and the Jeong(情) is response to the stimulation from the world. 5. By the actions of Seong(性) and Jeong(情), the human body has different JangBu(臟腑) function, so the human body can be grouped in four constitutions. 6. Because of emphasis on mind condition, the Sasang JangBu(臟腑) theory has activism of human beings itself. 7. This activismor practical philosophy of Sasang JangBu(臟腑) theory, that is a physiology of Sasang Constitutional Medicine, gave birth to ethics or morality in Medical philosophy, that the human practice of ethics or morality bring a health and well being of human body.

• Journal of The Korean Astronomical Society
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• v.43 no.3
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• pp.75-93
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• 2010

We present the characteristics of the Seoul National University 4k Camera (SNUCAM) and report its performance on the 1.5m telescope at the Maidanak observatory in Uzbekistan. SNUCAM is a CCD camera with a pixel scale of 0.266" in $4096{\times}4096$ format, covering $18.1'{\times}18.1'$ field of view on the 1.5m. The camera is currently equipped with Bessell UBVRI, $H{\alpha}$, SDSS ugriz, and Y-band filters, allowing us to carry out a variety of scientific programs ranging from exoplanet studies to survey of quasars at high redshift. We examine properties of SNUCAM such as the bias level and its temporal variation, the dark current, the readout noise, the gain, the linearity, the fringe patterns, the amplifier bias, and the bad pixels. From our observations, we also constructed the master fringe frames in I-, z-, and Y-band. We outline some of the current scientific programs being carried out with SNUCAM, and demonstrate that SNUCAM on the 1.5m can deliver excellent images that reach to the $5-{\sigma}$ detection limits of R~25.5 mag and z~22.7 mag in 1 hour total integration.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.36.1-36.1
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• 2020

The progenitor of Type Ia supernovae (SNe Ia) is mainly believed to be a carbon/oxygen white dwarf (WD) with non-degenerate (single degenerate) or another WD companion (double degenerate). However, there is little observational evidence of their progenitor system. Recent studies suggest that shock-breakout cooling emission after the explosion can constrain the size of the progenitor system. To do so, we obtained a optical/Near-IR light curve of SN 2019ein, a normal but slightly sub-luminous type Ia supernova, from the very early phase using our high-cadence observation of Intensive Monitoring Survey of Nearby Galaxies (IMSNG). Assuming the expanding fireball model, the simple power-law fitting of the early part of the light curve gives power indices of 1.91 (B) and 2.09 (R) implying radioactive decay of 56Ni is the dominant energy source. By comparison with the expected light curve of the cooling emission, the early observation provides us an upper limit of the companion size of R∗≤1R⊙. This result suggests that we can exclude a large companion such as red giants, which is consistent with the previous study.

• Publications of The Korean Astronomical Society
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• v.27 no.4
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• pp.383-389
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• 2012

This report presents a summary of the Legacy of AKARI: A Panoramic View of the Dusty Universe meeting held between 27-29th February 2012 at Jeju Island, South Korea.

• Journal of The Korean Astronomical Society
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• v.37 no.5
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• pp.413-420
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• 2004

The current state and future prospects of ultra high energy cosmic ray physics are reviewed. These cosmic rays with energies well above $10^{18}$ eV are messengers of an unknown extremely high-energy universe.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.27-29
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• 1996

We describe the formation of large-scale inhomogeneous structure of expa-nding Universe on the basic of two components system-usual nonrelativistic particles and dark matter, with taking into account their interaction.