• Title/Summary/Keyword: SED

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Mid-Infrared Luminosity Function of Local Galaxies in the North Ecliptic Pole Region

  • Kim, Seong-Jin;Lee, Hyeong-Mok
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.38.1-38.1
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    • 2013
  • We present observational estimation of the infrared (IR) luminosity function (LF) of local (z < 0.3) star-forming (SF) galaxies derived from the AKARI NEP-Wide samples. We made an analysis of the NEP-Wide data with optical spectroscopic information allowing an accurate determination of luminosity function. Spectroscopic redshifts for about 1650 objects were obtained with MMT/Hectospec and WIYN/Hydra, and the median redshifts is about 0.22. To measure the contribution of SF galaxies to the luminosity function, we excluded AGN sample by comparing their SEDs with various model template. Spectroscopic redshifts and the AKARI's continuous filter coverage in the mid-IR (MIR) wavelength (2 ~ 25 micron) enable us to avoid large uncertainties from the mid-IR SED of galaxies and corresponding k-corrections. The 8-micron luminosity function shows a good agreement with the previous works in the bright-end, whereas it seems not easy to constrain the faint-end slope. The comparison with the results of the NEP-Deep data (Goto et al. 2010) suggests the luminosity evolution to the higher redshifts, which is consistent with the down-sizing evolutionary pattern of galaxies.

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Photometric Reverberation Mapping with SQUEAN: A Test Study using Medium Bands

  • Taak, Yoon Chan;Im, Myungshin;Choi, Changsu
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.71.1-71.1
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    • 2016
  • Photometric reverberation mapping is an effective alternative to time consuming spectroscopy. It usually employs narrow bands to track the luminosity variations of broad emission lines, such as Balmer lines, and broadbands for the continuum variability. Here, we investigate the feasibility of substituting these for medium bands, with 50nm widths, that are currently being used on the SED Camera for QUasars in EArly uNiverse (SQUEAN) installed on the 2.1m Otto Struve Telescope at McDonald Observatory. Three targets with recent variability and/or short expected time lags were selected, and observed for 15 minutes each in the medium band containing $H{\alpha}$, and the two adjacent bands for continuum subtraction afterwards. Analysis shows that for one of the objects, SDSS J0350+0037, the pure $H{\alpha}$ emission line flux has a S/N ~ 12, so that variabilities up to ~ 8% are detectable. Thus, future observations using these medium bands on SQUEAN seem to be practical.

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Noodle Making Characteristics of Buckwheat Composite Flours (메밀복합분을 이용한 제면 특성)

  • 김복란;최용순;김종대;이상영
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.28 no.2
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    • pp.383-389
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    • 1999
  • To determine the optimum condition for buckwheat noodle making, we prepared noodle from com posite flours of buckwheat, wheat and corn starch, and those physical properties and sensory evalua tion were investigated. The weights of cooked noodle became lower with increasing buckwheat content level indicating that elution of its components to soup was high. Wheat flour in the composite flours probably caused to drop gelatinization temperature and maximum viscosity compared to buck wheat flours. Corn starch in the composite flours increase gelatinization temperature and maximum viscosity compared to buckwheat flours. From the result of farinogram, buckwheat flour lower water absorption ability, and increased dough development time compared to composite flours. Adhesiveness of the cooked noodle with wheat flour was decreased. Cohesiveness of the cooked noodle was decrea sed with increasing buckwheat flour level. In sensory evaluation, chewing and softness of noodle with 100% buckwheat flour was evaluated the best. In taste, BW1 and BSW1 noodles showed slightly higher preference although there was no significant differences.

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Host galaxy of tidal disruption object, Swift J1644+57

  • Yoon, Yongmin;Im, Myungshin;Lee, Seong-Kook;Pak, Soojong
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.48.2-48.2
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    • 2014
  • We present long-term optical to NIR data of the tidal disruption object, Swift J1644+57. The data were obtained with CQUEAN, UKIRT WFCAM observations. We analyze the morphology of the host galaxy of this object and decompose the bulge component using high resolution HST WFC3 images. We conclude that the host galaxy is bulge dominant. We also estimate the multi-band fluxes of the host galaxy through the light curves based on the long-term observational data. We fit the SED models to the multi-band fluxes of the host galaxy and determine its stellar mass. Finally, we estimate the mass of the central super massive black hole which is responsible for the tidal disruption event. The estimated stellar mass and black hole mass are ${\sim}10^{9.1}M_{\odot}$, ${\sim}10^{6.8}M_{\odot}$, respectively. We compare our results to other previous estimates.

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HOST GALAXY OF TIDAL DISRUPTION OBJECT, SWIFT J1644+57

  • YOON, YONGMIN;IM, MYUNGSHIN;LEE, SEONG-KOOK;PAK, SOOJONG
    • Publications of The Korean Astronomical Society
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    • v.30 no.2
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    • pp.475-476
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    • 2015
  • We analyze the host galaxy of the tidal disruption object, Swift J1644+57, based on long-term optical to NIR data obtained with CQUEAN and UKIRT WFCAM observations. We decompose the bulge component using high resolution HST WFC3 images. We conclude that the host galaxy is bulge dominant. We investigate optical to NIR light curves and estimate the multi-band fluxes of the host galaxy. We fit spectral energy distribution (SED) models in order to determine the stellar mass. Finally, we estimate the mass of the black hole in the center of the host galaxy based on several scale relations.

The Spitzer Public Legacy Survey of the 1 square degree UKIDSS Ultra Deep Survey (SpUDS)

  • Kim, Min-Jin;Dunlop, James S.;Lonsdale, Carol J.;Farrah, Duncan;Lacy, Mark;Sun, Ming;SpUDS team, SpUDS team
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.1
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    • pp.51.2-51.2
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    • 2011
  • The Spitzer Public Legacy Survey of the UKIDSS Ultra Deep Survey (SpUDS) has been carried out with four IRAC bands and one MIPS band (24um). SpUDS surveys 1 square degree of the UDS field, that has been covered by one of the deepest near IR surveys and by various multiwavelength observations from X-ray to radio (XMM, GALEX, Subaru, SCUBA, VLA). We present a summary of the photometric data including number counts derived at 3.6-24 microns. In conjunction with extensive multiwavelengh data, we are able to show the multiwavelenght color distribution of MIR sources, and how different SED types contribute to the number counts.

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Novel High-Rate High-Performance Space-Time Codes

  • Le, Minh-Tuan;Mai Linh;Pham, Van-Su;Giwan Yoon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2004.05a
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    • pp.32-35
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    • 2004
  • In this paper, we propose two novel high-rate high-performance space-time codes for multiple-input multiple-output (MIMO) systems. When $n_{T}$ transmit antennas and $n_{R}$ = $n_{T}$ receive antennas are deployed, the two proposed codes respectively offer transmission rates of ( $n_{T}$ -I) and ( $n_{T}$ - 2) symbols per channel use and diversity orders of 3 and 5. As a consequence, our proposed codes allow the MIMO systems to employ a simple detection technique based on QR decomposition. Moreover, for equal or even higher spectral efficiencies, our proposed codes always provide much better bit error rate (BER) performances than V-BLAST architecture does when $n_{R}$ = $n_{T}$. Computer simulation is given to verify performances of our proposed codes.sed codes.des.

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A Study for Accelerated Life Testing and Failure Analysis of Chip Varistor (Varistor 의 ALT(Accelerated Life Testing) 설계 및 주 고장모드 분석)

  • Chang Woo-Sung;Lee Jun-Hyuk;Lee Kwan-Hun;Oh Young-Hwan
    • Proceedings of the Korean Reliability Society Conference
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    • 2005.06a
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    • pp.51-67
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    • 2005
  • General chip SMD parts(chip resistance, chip capacitor, chip varistor etc.) are very wide sed electronics parts for IT units. But, failure modes are indistinct for these chip parts. In factory and field the failure modes are recognized to accidental failure mope caused by potential defect. In this paper used chip varistor ALT(Accelerate Life Test) test for verify general failure modes in chip SMD parts. Also the results are useful for general chip SMD ALT tests.

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Effect of Processed Cyperi Rhizoma on Rat Kidney Function (수치(修治) 향부자 분획물의 흰쥐 신기능에 미치는 영향)

  • Kim, Tae-Hee;Yang, Ki-Sook;Park, Ji-Young
    • YAKHAK HOEJI
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    • v.42 no.1
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    • pp.70-74
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    • 1998
  • Cyperus rotundus L. (Cyperaceae) has been used as an analgesic, antiinflammatoty agent, diuretic and emmenagoga in folk remedies. Cyperi Rhizomata, processed and unproces sed, were extracted with MeOH and fractionated with petroleum ether (Pet. Ether), $CHCl_3$, BuOH, water. In order to investigate the effects of their fractions on kidney function of acute renal failure rats induced by $HgCl_2$ urinary volume, BUN, Creatinine, Uric acid were determined. The diuretic effect of processed Cyperi Rhizoma was significantly increased in renal failure rats, on serum chemical parameters, the significant inhibition of BUN (blood urea nitrogen) of processed Cyperi Rhizoma was revealed.

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The Movement Monitoring of Structures using GPS

  • Shon, Howoong;Oh, Seok Hoon;Kim, Youngkyung
    • Journal of the Korean Geophysical Society
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    • v.7 no.4
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    • pp.325-330
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    • 2004
  • For the monitoring of structures, it is desirable for the measurement system to deliver equal precision in all components. When using GPS the accuracy, availability, reliability and integrity of the position solutions is very dependent on the number and geometric distribution of the available satellites. Therefore the positioning precision is not the same in all there component, and large variations (in positioning) precision can be expected during a 24-hour period. This situation becomes worse when the line-of-sight to GPS satellites becomes obstructed, such as in urban environments. Pseudolites can be sed to augment GPS and improve a geometrically weak satellite constellation. The use of pseudolites as supplement(s) of GPS for the movement measurement of bridges is demonstrated in this paper. It is shown that pseudollites can improve the vertical position components.

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