• Title/Summary/Keyword: HST

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Sequence Stratigraphy of Late Quaternary Deposits in the Southeastern Continental Shelf, Korea (한국 남동 대륙붕 후 제4기 퇴적층의 시퀀스 층서)

  • 유동근;이치원;최진용;박수철;최진혁
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.8 no.4
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    • pp.369-379
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    • 2003
  • Analysis of high-resolution seismic profiles and sediment data from the southeastern continental shelf of Korea reveals that the late Quaternary deposits consist of a set of lowstand (LST), transgressive (TST), and highstand systems tracts (HST) that corresponds to the sea-level change after the Last Glacial Maximum. LST (Unit I) above the sequence boundary consists of sandy mud or muddy sand deposited during the last glacial period and is confined to the shelf margin and trough region. TST (Unit II) between transgressive surface and maximum flooding surface consists of sandy sediments deposited during the postglacial transgression (15,000-6,000 yr BP). Although TST is widely distributed on the shelf, it is much thinner than LST and HST. On the basis of distribution pattern, TST can be divided into three sub-units: early TST (Unit IIa) on the shelf margin, middle TST (Unit IIb) on the mid-shelf, and late TST (Unit IIc) on the inner shelf, respectively. These are characterized by a backstepping depositional arrangement. HST(Unit III) above the maximum flooding surface is composed of the fine-grained sediments deposited during the last 6000 yrs when sea level was close to the present level and its distribution is restricted to the inner shelf along the coast.

Shift Characteristics Analysis of Transmission for Construction Vehicles (건설차량용 변속장치의 특성 해석)

  • 윤소남;함영복;류찬수;최병오
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.674-679
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    • 2002
  • As the object of this study, a transmission system with the style of HST in combination with mechanical semi-automatic transmission for application in hydraulic wheel excavators was chosen. The dynamic characteristics of the object transmission was studied by numerical analysis of the mathematical model. The results of numerical analysis showed comparatively good agreements with experimental results, so the validity of the numerical analysis process was ascertained.

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Rest-frame optical spectroscopic properties of submillimeter galaxies

  • Shim, Hyunjin
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.2
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    • pp.74.3-74.3
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    • 2017
  • Considering the statistical redshift distribution of the known submillimeter galaxy (SMG) population, most of the significant optical emission lines such as [OII]${\lambda}3727$, $H{\beta}$, [OIII]${\lambda}5007$, and $H{\alpha}$ are redshifted into near-infrared. Using the 3D-HST grism data that provides low resolution NIR spectroscopy over the several deep fields covered by the JCMT large program S2CLS, I investigated the properties of the optical emission lines for submm galaxies which could be used as a proxy for future optical/NIR identification and follow up of the SMGs.

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Ca-CN Photometry of M5: A New Saga Begins

  • Lee, Jae-Woo
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.2
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    • pp.51.2-51.2
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    • 2017
  • As a result of our decade-long effort, we developed a new approach wherein small-aperture telescope powered by ingeniously designed narrow-band filter systems can have the capability to measure not only the heavy but also the lighter elemental abundances of the red-giant branch (RGB) and asymptotic-giant branch (AGB) stars in the globular clusters. Our novel approach can complement the intrinsic weakness of the results from the prestigious instruments, such as HST and the VLT. In our talk, we will present the multiple stellar populations of the RGB and the AGB stars in M5, as a pilot work.

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Kinematics and Geometrical Structure of the Planetary Nebula NGC 6881 (행성상 성운 NGC 6881의 운동학적 특성과 기하학적 구조)

  • Lee, Sang-Min;Hyung, Siek
    • Journal of the Korean earth science society
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    • v.28 no.7
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    • pp.847-856
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    • 2007
  • The Planetary nebula NGC 6881 displays quadrupole morphology and it also has a jet feature in its image. We investigated the line profiles of the optical region spectral emission lines, using the Hamilton Echelle Spectrograph (HES) at the Lick observatory. The HES data obtained in this study was the radiation coming from the inner region within the diameter of 4 second of arc. Expansion velocity was obtained, based on the strong emission line profiles of e.g. H, Hel, Hell, [OIII], [NII], [ArIII], [SII], and [SIII}, using the IRAF and StarLink/Dipso reduction packages. The HI recombination lines showed one single peak profile, while the He and forbidden strong lines displayed double peaks. The results of this study show that the outflow velocity of gas increases radially outwards due to the central stellar radiation pressure. It was concluded that three central rings appeared in the HST image are the result of a combined structure of bipolar cones (seen in e.g. HI lines) and a ring (seen in He, [SIII] lines) in projection.

A Control of the ZVZCS PS-FB DC/DC Converter using All-Pass Filter (전역통과필터를 이용한 ZVZCS PS-FB DC/DC 컨버터의 제어)

  • Cho, Han-Jin;Lee, Won-Cheol;Lee, Sang-Seok;Lee, Su-Won;Won, Chung-Yuen
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.24 no.1
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    • pp.152-159
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    • 2010
  • High power density and power conversion efficiency have been required in the power converters according to the rapid growth of industry. In this context, the next generation High Speed Train(HST) requires power converter which has high-efficiency, high-performance and high-density. In this paper, the new control technique for battery charger used for the next generation HST is proposed. The phase shift ZVZCS converter is classified according to a resonant circuit which is located in the primary or secondary side. In this paper, The PWM switching technique using all-pass filter is proposed to control ZVZCS converter which has resonant circuit in the secondary side. ATmega_128 micro controller based in all-pass filter in substitute for phase shift IC is presented to have digital control. To verify the proposed topology, the simulation and experiment are performed by using PSIM software and 1[kW] experimental set-up.

Analysis of Solute Transport with Steady State Groundwater Flow in Layered Aquifer (정상 지하수흐름을 갖는 층상대수층에서의 용질이동해석)

  • Lee, Seung-Han;Jeong, Il-Mun
    • Journal of Korea Water Resources Association
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    • v.30 no.1
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    • pp.23-34
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    • 1997
  • The Nanji-Do ladnfill is an ill-conditioned reclaimed land without pollution intercepting facilities, and has high ground water table and deep stratum. The purpose of this study is to analyze the solute transport in steady-state groundwater flow and to predict the solute dispersion in Nanji-Do landfill using HST-3D model. As results, the groundwater flows radially outward from the center of No. 1 and No. 2 landfills, and large amount of runoff is moved into Han River. The predicted relative concentration of total dissolved solute(TDS) at two years later was 0.25 in the weathering zone, 0.26 in the lower alluvium, and 0.28 in the upper alluvium. Thus, the further pollution to bottom rock and Han River was predicted by comparing the corresponding present values of 0.29, 0.32 and 0.35.

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A Study of the Correlation Between the Siblings Relation and the Personality Characteristics on the Oriental Medical University Students by MMPI Profiling (MMPI 척도로 본 한의대생의 형제자매관계와 성격특성의 연관성에 관한 연구)

  • Ha, Ji-Won;Jung, Jin-Heong;Kim, Bo-Kyung
    • Journal of Oriental Neuropsychiatry
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    • v.23 no.4
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    • pp.123-132
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    • 2012
  • Objectives : This study aims to investigate the correlation between the characteristics of personality on MMPI scale, and the siblings relation, number of current family living with, gender and age of the Oriental Medical University students. Methods : For this study, we carried out the MMPI profiling and gathered information regarding the sibling relation of the subjects. We studied the correlation between the two measures, and the correlation between MMPI scales and the subjects' gender and age. Results : 1. The group without siblings had higher STY figures then the groups with siblings. 2. There was no significant differences in MMPI profiles among the only child group, first-born group, second-born group, and third-born group. 3. The married group showed higher Pd, Pt, Sc, BDL figures than the unmarried group. 4. As the number of family members currently living with increased, the BDL and STY figures decreased. 5. The male group had higher Hs, Hy, Pa, Ma, NAR, BDL, ANT, CPS, PAR, and SZD figures, while the female group had higher D, Pd, Mf, Pt, HST, PAG, and DEP figures. 6. As the subjects' age increased, the figure of Hs, D, Pt, Sc, Si, AVD, and SZD increased, while the HST figure decreased. Conclusions : By the above results, we can assume that the sibling relations and the order one is born in the family does not affect one's personality much in grown-ups; whereas the gender and age affect the personality.

DISCOVERY OF WHITE DWARFS IN THE GLOBULAR CLUSTERS M13 AND M22 USING HST ACS PHOTOMETRIC DATA

  • CHO, DONG-HWAN;YOON, TAE SEOG;LEE, SANG-GAK;Sung, HYUN-IL
    • Journal of The Korean Astronomical Society
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    • v.48 no.6
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    • pp.333-341
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    • 2015
  • A search for hot and bright white dwarfs (WDs) in the Milky Way globular clusters M13 (NGC 6205) and M22 (NGC 6656) is carried out using the deep and homogeneous V I photometric catalog of Anderson et al. and and Sarajedini et al., based on data taken with the ACS/WFC aboard the Hubble Space Telescope (HST). V versus V − I color-magnitude diagrams (CMDs) of M13 and M22 are constructed and numerous spurious detections are rejected according to their photometric quality parameters qfit(V ) and qfit(I). In the case of M13, further radial restriction is applied to reject central stars with higher photometric errors due to central crowding. From each resultant V versus V −I CMD, sixteen and thirteen WD candidates are identified in M13 and M22, respectively. They are identified as stellar objects in the accompanying ACS/WFC images and are found to be randomly distributed across the central regions of M13 and M22. Their positions in the CMDs are in the bright part of the DA WD cooling sequences indicating that they are true WDs. In order to confirm their nature, follow-up spectroscopic observations are needed.