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Black Hole Activities of Red Active Galactic Nuclei

  • Kim, Dohyeong;Im, Myungshin;Woo, Jong-Hak
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.1
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    • pp.72.1-72.1
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    • 2015
  • We investigate black hole (BH) activities of 16 red active galactic nuclei (AGNs). The 16 red AGNs selected by red colors in optical through near-infrared (NIR) and radio detection. In order to derive BH activities of the red AGNs, we use $P{\beta}$ line with NIR spectra obtained by the SpeX on the IRTF. The $P{\beta}$ line suffers from dust extinction less than UV/optical BH mass estimators. We compared Eddington ratios of the red AGNs and "normal" AGNs, and the Eddington ratios of red AGNs are significantly higher than those of "normal" AGNs. The result is consistent with a scenario that red AGNs are the intermediate population between star forming galaxies and "normal" AGNs, and BHs of red AGNs are very active and grow rapidly in such a stage.

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Geographical Distribution and Soil Characteristics of Elaeagnus Plants in Korea (한국산 보리수나무속 식물의 분포 및 생육지 토양 특성)

  • You, Young-Han;Kim, Kyung-Bum;An, Chung-Sun;Kim, Joon-Ho;Song, Seung-Dal
    • The Korean Journal of Ecology
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    • v.17 no.2
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    • pp.159-170
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    • 1994
  • The geographical distribution and soil characteristics of Korean Elaeagnus plants were investigated by literatures, field survey and soil analysis. Deciduous E. umbellata was distributed throughout the Korean peninsula including western and southern islands. Distribution area of evergreen Elaeagnus plants was classified into three groups; E. macrophylla and E. glabra belonged to group l occurring in the southern, western and eastern islands; E. submacrophylla to group 2 occurring in the southern and western islands; E. maritima and E. ankaii to group 3 in the southern islands only. Deciduous E. umbellata appeared euryeciously from poor soil to rich one, whereas evergreen Elaegnus plants appeared stenoeciously in haline soil near coast.

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Effect of Degradation Processes on Optimal Remediation Design Sorption and First-Order Decay Rate

  • Park, Dong-Kyu;Ko, Nak-Youl;Lee, Kang-Kun
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.04a
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    • pp.503-508
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    • 2004
  • Optimal remediation design using the pump and treat(P&T) method and natural attenuation was accomplished in consideration for degradation processes, such as sorption and first-order decay rate. Variation of both sorption and first-order decay rate has influence on design of optimal remediation application. When sorption effect increases, the more pumping rate and pumping wells are required. The location of operated wells is on the centerline of contaminant plume and wells near hot spot are mainly operated when sorption effect increases. The higher of first-order decay rate, the less pumping rate is required. These results show that the degradation processes have to be considered as one of the essential factors for optimal remediation design.

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Anatomical studies on the ear muscles of the Korean native goat (한국재래산양의 이개근에 대한 해부학적 연구)

  • Lee, Chang-hyun;Lee, Heungshik S.;Lee, In-se
    • Korean Journal of Veterinary Research
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    • v.29 no.3
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    • pp.239-244
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    • 1989
  • This study was carried out to investigate the origin, insertion, direction of muscle fibers and structure of the ear muscles of the Korean native goat. The description was based on the dissection of fifteen the Korean native goats with embalming fluid. The results were as follows: 1. The ear muscles of the Korean native goat were composed of the M. zygomaticoauricularis, M. scutuloauricularis superficialis, M. scutuloauricularis profundus, M. frontoscutularis, M. interscutularis, M. parietoauricularis, M. cervicoscutularis, M. cervicoauricularis superficialis, M. cervicoauricularis medius, M. cervicoauricularis profundus, M. auricularis profundus posterior and M. parotidoauricularis. 2. The M. frontoscutularis clearly seperated into temporal and frontal parts in 6 cases. 3. The M. scutuloauricularis profundus clearly separated into major and minor parts. 4. The M. zygomaticoauricularis blended with the M. parotidoauricularis near its insertion, but not with the M. scutuloauricularis.

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Terminal Myelocystocele : Pathoembryogenesis and Clinical Features

  • Lee, Ji Yeoun;Kim, Kyung Hyun;Wang, Kyu-Chang
    • Journal of Korean Neurosurgical Society
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    • v.63 no.3
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    • pp.321-326
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    • 2020
  • There has been confusion in the classification of terminal myelocystocele (TMCC) due to its diverse morphology and vague pathoembryogenesis. TMCC could be summarized as having the essential features of an elongated caudal spinal cord extruding out of the dorsal extraspinal space that fuses with the subcutaneous fat, which is in the shape of a trumpet-shaped cerebrospinal fluid-filled cyst. The extraspinal portion of the extruded spinal cord is nonfunctional. The morphological features suggest that TMCC is formed during secondary neurulation, specifically the failure of the degeneration of the secondary neural tube near the time of the terminal balloon. This review discusses the definition, as well as the clinical and surgical features, of TMCC with special emphasis on its pathoembryogenesis.

Isolated Congenital Left Ventricular Diverticulum in Adults

  • Jung, Joon Chul;Oh, Hong Chul;Kim, Kyung-Hwan
    • Journal of Chest Surgery
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    • v.48 no.5
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    • pp.355-358
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    • 2015
  • Isolated congenital left ventricular diverticulum is a rare cardiac malformation. Here, we report the case of a 33-year-old woman who had suffered from recurrent transient ischemic attacks for 6 years. Preoperative cardiac magnetic resonance imaging and computed tomography angiography revealed a diverticulum near the apex. The diverticulum was successfully obliterated by cardiopulmonary bypass. We suggest that isolated congenital left ventricular diverticulum can be easily corrected with a low surgical risk by patch repair and plication techniques.

TREATMENT OF INVERTED MAXILLARY INCISOR (Inverted Maxillary Incisor의 치료)

  • Shin, Soo-Jeong;Chang, Young-In;Suhr, Cheong-Hoon
    • The korean journal of orthodontics
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    • v.23 no.1 s.40
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    • pp.137-145
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    • 1993
  • Inverted maxillary incisor is that maxillary incisor rotates to the counterclockwise direction. The incisal margin and root apex of the impacted incisor is palpated at the mucobuccal fold near the labial frenum and on the palate among the rugae, respectively. Orthodontists confront ectopically erupting teeth in various locations. In the past, extraction of impacted teeth that deviated from their normal course of eruption had been performed indiscriminately. But, if it has not any clearcut contraindications, effeort should be made to achieve optimal esthetic results by conservative means, combining the skills of oral surgeon and orthodontist. The present report provides an illustration of satisfactory correction of a inverted maxillary incisor with surgical intervention and many springs that correct the tooth axis. This technique provides the clinician with an additional means to avoid unnecessary extraction of inverted teeth in certain cases.

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Harmonic Reduction of Parallel-Connected Thyristor Rectifiers with an Active Interphase Reactor

  • Choi, Sewan;Oh, Junyong;Kim, Kiyong
    • Proceedings of the KIPE Conference
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    • 1998.10a
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    • pp.276-280
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    • 1998
  • This paper proposes a harmonic a harmonic reduction technique of the parallel-connected twelve-pulse thyristor rectifiers. The proposed system is an improvement over the diode rectifier system with an active interphase reactor [2]. In this scheme, a low KVA (0.15 Po (PU) ) active current source injects a triangular current into an interphase reactor of a twelve-pulse thyristor rectifier along the phase delay angle. The current injection results in near sinusoidal input current with less than 1% THD. Detailed analysis of the proposed scheme along scheme along with design equations is illustrated. Simulation results verify the concept.

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MODELING AND OPTIMIZATION Of A FIXED-BED CATALYTIC REACTOR FOR PARTIAL OXIDATION OF PROPYLENE TO ACROLEIN

  • Lee, Ho-Woo;Ha, Kyoung-Su;Rhee, Hyun-Ku
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.451-451
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    • 2000
  • This study aims for the optimization of process conditions in a fixed-bed catalytic reactor system with a circulating molten salt bath, in which partial oxidation of propylene to acrolein takes place. Two-dimensional pseudo-homogeneous model is adopted with estimation of suitable parameters and its validity is corroborated by comparing simulation result with experimental data. The temperature of the molten salt and the feed composition are found to exercise significant influence on the yield of acrolein and the magnitude of hot spot. The temperature of the molten salt is usually kept constant. This study, however, suggests that the temperature of the molten salt must be axially adjusted so that the abrupt peak of hot spot should not appear near the reactor entrance. The yield of acrolein is maximized and the position and the magnitude of hot spot are optimized by the method of the iterative dynamic programming (IDP).

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UBV CCD PHOTOMETRY OF INTERMEDIATE AGE OPEN CLUSTER M11 I. STATISTICAL ANALYSIS

  • SUNG HWANKYUNG;LEE SEE-WOO;LEE MYUNG GYOON;ANN HONG BAE
    • Journal of The Korean Astronomical Society
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    • v.29 no.2
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    • pp.269-278
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    • 1996
  • We present the color-magnitude diagrams (CMD) of more than 24,000 stars in the field of an intermediate age open cluster M11, based on wide field CCD imaging. The morphology of the CMDs varies strikingly as the distance from the center of the cluster increases. From the surface number density analysis, we confirm the mass segregation effect in this cluster: the bright, massive stars are centrally more concetrated than the faint, low mass stars. The slope of the field-corrected surface density with respect to magnitude progressively increases as the radius increases, up to r = 5'. Most of the field stars in or near the cluster main sequence band and in the bright part of the red stars in the CMDs appear to be nearly at the same distance as M11, and they are considered to be the major component of disk stars in the Sagittarius-Carina arm.

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