• Journal of the Korean Society of Food Science and Nutrition
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• v.3 no.1
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• pp.17-21
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• 1974

Tasty constituents such as free amino acids. free organic acids and free sugars and minerals in clavariaceae botrytis were surveyed through the course of this study. The results were as, follows: 1. Isoleucine valine threonine alanine methionine cysteine glutamine histidine glutamic acid and aspartic acid were presented in clavariaceae botrytis, and aspartic acid showed the highest amount. 2. Succinic acid was the major organic acid in clavariaceae botrytis, and also citric acid malic acid and fumaric acid were presented. 3. Clavariaceae botrytis contained fructose, maltose glucose and sucrose ; glucose and sucrose were more than 80% of total sugars. 4. Na K Mg Ca Zn Mn Cu am Fe by atomic absorption spectrometer were detected and assayed. and Al Si Ni Sn Ti Cr Ag Pb B and Sr detected by emission spectrograph. K of these minerals showed the highest amount but very small amount of Ca was presented.

• Bulletin of the Korean Space Science Society
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• 2003.10a
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• pp.52-52
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• 2003

1996년 미국 버클리 대학의 Space Science Laboratory와 공동으로 고온 성간 물질의 관측에 대한 Conceptual Study로부터 시작되어 1998년 과학위성 1호의 주 탑재체로 선정되면서 본격적인 개발에 들어간 원자외선 분광기(FIMS: Far-ultraviolet IMaging Spectrograph)는 Engineering Model 개발, Qualification Model 개발, Flight Model의 개발 및 보정, 그리고 최종적으로 과학기술위성 1호 본체와의 조립 시험 및 환경시험을 거쳐 2003년 9월 26일 러시아의 플레세츠크에서 COSMOS-3M 발사체에 의해 발사된다. FIMS를 포함한 과학위성 1호는 현재 발사를 위해 러시아 현지에 이송되어 최종 시험을 진행 중이며, 발사 후 약 20일 가량은 위성의 운용 시험을 하게 되며, 이후 FIMS의 운용에 영향을 줄 수 있는 Out-gassing이 충분히 이루어진 후 FIMS의 Test 및 초기 운용이 이루어 진다. FIMS의 Detector로 사용되는 MCP(Micro Channel Plate)의 정상적 동작이 확인되면, 1년여에 걸쳐 FIMS의 주 임무인 원자외선 영역(900∼1750')의 은하계 전천 탐사를 수행하게 된다. 전천 탐사가 마무리 되면, 전천탐사의 결과를 바탕으로 개별 천체의 영상 및 분광 자료를 획득하게 되며, 동시에 원자외선 영역의 오로라 및 지구 대기광 측정을 수행한다.

• Bulletin of the Korean Space Science Society
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• 2008.10a
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• pp.31.2-31.2
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• 2008

We present the results offar ultraviolet (FUV, 1350-1750 ${\AA}$) auroral observations made by the Far-ultraviolet IMaging Spectrograph (FIMS) instrument on the Korean microsatellite STSAT-1. The instrument was capable of resolving spatial structures of a few kilometers with the spectral resolution of 2-3 ${\AA}$. The observations were carried out simultaneously with the measurement of precipitating electrons using an electrostatic analyzer (ESA, 100 eV-20 keV) and a solid state telescope (SST, 170 keV-360 keV) on board the same satellite. With a careful mapping of the field lines, we were able to correlate the particle spectrum to the corresponding FUV spectrum of the footprints of the FIMS image that varied significantly in fine scales. We divided the FIMS spectral band into the LBH long (LBHL, 1640-1715 ${\AA}$) and LBH short (LBHS, 1380-1455 ${\AA}$) bands, and compared the electron energies with the intensities of LBHL and LBHS for the well-defined inverted-V structures. The result shows a strong correlation between the total LBH intensity and the energy flux measured by ESAwhile the peak energy itself does not correlate well with the LBH intensity. On the other hand, it was observed that the ratio of the LBHL intensity to that of LBHS increased significantly as the peak electron energy increased, primarily due to a smaller absorption by O2 at LBHL than at LBHS.

• Journal of Astronomy and Space Sciences
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• v.18 no.3
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• pp.209-218
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• 2001

Global exposure time distribution through all-sky survey, one of main science missions of KAISTSAT-1, has been simulated. Exposure time distribution has its minimum on the celestial equator and increases with moving to polar regions according to the present mission operation scenario. SAA (South Atlantic Anomaly) and the moon can make further decreases of exposure time around the celestial equator Effects of SAA on all-sky survey exposure time can be compensated with a simple observational scheduling, orbit exchange between orbits allocated to all-sky survey passing through the SAA region and ones allocated to upper atmosphere observations not affected by SAA. It, however, seems that present exposure time distribution is not adequate for the concrete study of the evolution of interstellar medium. A scheme for active time allocation is needed for redistribution of exposure times weighted around the celestial poles, and additional studies on the advanced mission operation and the observational scheduling are also needed.

• Journal of Astronomy and Space Sciences
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• v.31 no.2
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• pp.177-186
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• 2014

The Immersion Grating Infrared Spectrometer (IGRINS) is a near-infrared wide-band high-resolution spectrograph jointly developed by the Korea Astronomy and Space Science Institute and the University of Texas at Austin. IGRINS employs three HAWAII-2RG Focal Plane Array (H2RG FPA) detectors. We present the design and fabrication of the detector mount for the H2RG detector. The detector mount consists of a detector housing, an ASIC housing, a Field Flattener Lens (FFL) mount, and a support base frame. The detector and the ASIC housing should be kept at 65 K and the support base frame at 130 K. Therefore they are thermally isolated by the support made of GFRP material. The detector mount is designed so that it has features of fine adjusting the position of the detector surface in the optical axis and of fine adjusting yaw and pitch angles in order to utilize as an optical system alignment compensator. We optimized the structural stability and thermal characteristics of the mount design using computer-aided 3D modeling and finite element analysis. Based on the structural and thermal analysis, the designed detector mount meets an optical stability tolerance and system thermal requirements. Actual detector mount fabricated based on the design has been installed into the IGRINS cryostat and successfully passed a vacuum test and a cold test.

• Journal of The Korean Astronomical Society
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• v.41 no.6
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• pp.163-172
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• 2008

Using the spectral data in the 3700 to $10050{\AA}$ wavelength range secured with the Hamilton Echelle Spectrograph (HES) at the Lick observatory, we have investigated the expansion velocities and the physical conditions of the elliptical planetary nebula NGC 6803. Various forbidden and permitted lines, e.g. HI, HeI, HeII, [OIII], [NII], [ArIII], and [SII], indicate complicated but systematic physical conditions variation: electron temperatures $T_{\varepsilon}\;{\sim}\;9000$ - 11000 K and electron number densities $N_{\varepsilon}\;{\sim}\;2000$ - $9000\;cm^{-3}$. The line profile analysis of these ions also indicates the systematic change or the acceleration of the expansion velocities in the range of 10 - $22\;km\;s^{-1}$. We show that the velocity gradient and physical condition found in various ions are closely related to the prolate ellipsoidal structure of NGC 6803. The expansion velocity and the ionic abundance of $O^{2+}$ were derived based on the OII and [OIII] lines. In spite of the discrepancy of ionic abundances derived by the two cases and their line profiles, the expansion velocities of them agree well. We find that the ratios of the red to blue line component of the HeII & OII lines are different from those of the [OIII] or other forbidden lines that indicates a possible involvement of emission of HeII & OII lines. This subtle difference and the different physical condition of the lines are likely to be caused by the elongated geometry and the latitude dependence of the emission zone.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.98-98
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• 2014

Due to the simple vertical structure of magnetic field, pores can be exploited to study the transport of mechanical energy by waves along the magnetic field to the chromosphere and corona. For a better understanding of physics of pores, we have investigated chromospheric traveling features running across two merged pores from their centers at the speed about 55 km s-1, in the active region AR 11828. The pores were observed on 2013 August 24 by using high time, spatial, and spectral resolution data from the Fast Imaging Solar Spectrograph (FISS) of the 1.6 meter New Solar Telescope (NST). We infer a LOS velocity by applying the bisector method to the Ca II $8542{\AA}$ band and $H{\alpha}$ band, and investigate intensity and the line-of-sight velocity changes at different wavelengths and different positions at the pores. We find that they have 3 minutes oscillations, and the intensity oscillation from the line center is preceded by that from the core ($-0.3{\AA}$) of the bands. There is no phase difference between the intensity and the LOS velocity oscillations at a given wavelength. The amplitude of LOS velocity from near the core spectra is greater than that from the far core spectra. These results support the interpretation of the observed wave as a slow magnetoacoustic wave propagating along the magnetic field lines in the pores. The apparent horizontal motion and a sudden decrease of its speed beyond the pores can be explained by the projection effect caused by inclination of the magnetic field with a canopy.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.54.1-54.1
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• 2016

Stellar wind and radiation pressure from massive stars can trigger the formation of new generation of stars. The sequential age distribution of stars, the morphology of cometary globules, and bright-rimmed clouds have been accepted as evidence of triggered star formation. However, these characteristics do not necessarily suggest that new generation of stars are formed by the feedback of massive stars. In order to search for any physical connection between star forming events, we have initiated a study of gas and stellar kinematics in NGC 1893, where two prominent cometary nebulae are facing toward O-type stars. The spectra of gas and stars in optical and near-infrared (NIR) wavelength are obtained with Hectochelle on the 6.5m MMT and Immersion GRating INfrared Spectrograph on the 2.7m Harlan J. Smith Telescope at McDonald observatory. In this study, the radial velocity field of gas across the cluster is investigated using $H{\alpha}$ and [N II] ${\lambda}$ 6584 emission lines, and that of the cometary nebula Sim 130 is also probed using 1-0 S(1) transition line of $H_2$. We report a distinctive velocity field of the cometary nebulae and many ro-vibrational transitions of $H_2$ even at high energy levels in the NIR spectra. These properties indicate the interaction between the cometary nebulae and O-type stars, and this fact can be a clue to triggered star formation in NGC 1893.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.36.2-36.2
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• 2012

The aim of this study was to explore the role of galaxy mergers on the formation and evolution of galaxies in galaxy clusters. For this purpose, u', g', r' deep optical imaging and multi-object spectroscopic observation were done for four rich Abell clusters at z ${\lesssim}$ 0.1 (A119, A2670, A3330, and A389) with a MOSAIC 2 CCD and Hydra spectrograph mounted on a Blanco 4-m telescope at CTIO. With the deep images, we found that about 25% of the bright red-sequence galaxies exhibited post-merger signatures in a cluster environment. This fraction was much higher than what was expected from the results of the field environment (-35%, van Dokkum 2005) and significantly low on-going merger fractions (about one-fifth of the field) appeared in the clusters currently. Taking advantage of the most up-to-date semi-analytic model, the results indicate that most of the post-merger galaxies may have carried over their merger features from their previous halo environment. All the brightest cluster galaxies in our cluster samples revealed faint structures in their halos as well as multiple nuclei in their centers seen in the deep optical images. We suggest that the mass of the BCGs increased mainly though major mergers at recent epochs based on their post-merger signatures and the large gaps in the total magnitudes between the BCGs and the second-rank BCGs. A UV bright tidal tail and tidal dwarf galaxy (TDG) candidates around the post-merger galaxy, NGC 4922, were discovered in the outskirts of the Coma cluster using the GALEX UV data. We did two-component stellar population modeling for the TDG candidates and the results indicate that they are an early form of dwarf galaxies frequently found around massive early-type galaxies in clusters. In conclusion, we suggest that the mergers of galaxies are an important driving force behind galaxy formation and evolution in cluster environments even until recent epochs.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.89.1-89.1
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• 2012

We have investigated a coronal jet observed near the limb on 2010 June 27 by the Hinode/X-Ray Telescope (XRT), EUV Imaging Spectrograph (EIS), and Solar Optical Telescope (SOT), and the SDO/Atmospheric Imaging Assembly (AIA), Helioseismic and Magnetic Imager (HMI), and on the disk by STEREO-A/EUVI. From EUV (AIA and EIS) and soft X-ray (XRT) images we have identified both cool and hot jets. There was a small loop eruption in Ca II images of the SOT before the jet eruption. Using high temporal and multi wavelength AIA images, we found that the hot jet preceded its associated cool jet by about 2 minutes. The cool jet showed helical-like structures during the rising period. According to the spectroscopic analysis, the jet's emission changed from blue to red shift with time, implying helical motions in the jet. The STEREO observation, which enabled us to observe the jet projected against the disk, showed that there was a dim loop associated with the jet. We have measured a propagation speed of ~800 km/s for the dimming front. This is comparable to the Alfven speed in the loop computed from a magnetic field extrapolation of the HMI photospheric field measured 5 days earlier and the loop densities obtained from EIS Fe XIV line ratios. We interpret the dimming as indicating the presence of Alfvenic waves initiated by reconnection in the upper chromosphere.