• Title/Summary/Keyword: Observational period

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Development of Representative GCMs Selection Technique for Uncertainty in Climate Change Scenario (기후변화 시나리오 자료의 불확실성 고려를 위한 대표 GCM 선정기법 개발)

  • Jung, Imgook;Eum, Hyung-Il;Lee, Eun-Jeong;Park, Jihoon;Cho, Jaepil
    • Journal of The Korean Society of Agricultural Engineers
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    • v.60 no.5
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    • pp.149-162
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    • 2018
  • It is necessary to select the appropriate global climate model (GCM) to take into account the impacts of climate change on integrated water management. The objective of this study was to develop the selection technique of representative GCMs for uncertainty in climate change scenario. The selection technique which set priorities of GCMs consisted of two steps. First step was evaluating original GCMs by comparing with grid-based observational data for the past period. Second step was evaluating whether the statistical downscaled data reflect characteristics for the historical period. Spatial Disaggregation Quantile Delta Mapping (SDQDM), one of the statistical downscaling methods, was used for the downscaled data. The way of evaluating was using explanatory power, the stepwise ratio of the entire GCMs by Expert Team on Climate Change Detection and Indices (ETCCDI) basis. We used 26 GCMs based on CMIP5 data. The Representative Concentration Pathways (RCP) 4.5 and 8.5 scenarios were selected for this study. The period for evaluating reproducibility of historical period was 30 years from 1976 to 2005. Precipitation, maximum temperature, and minimum temperature were used as collected climate variables. As a result, we suggested representative 13 GCMs among 26 GCMs by using the selection technique developed in this research. Furthermore, this result can be utilized as a basic data for integrated water management.

Seismic Research Network in KIGAM (한국자원연구소 지진 네트워크)

  • 이희일
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2000.10a
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    • pp.49-56
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    • 2000
  • Instrumental observation of earth quakes in KIGAM was first attempted in the earty 1980`s by using 6 portable seismographs in the vicinity of Yang-San Faults. Now twenty-four permanent stations, which are equipped with short-period or broad-band seismometer, are included in seismic research network in KIGAM, including KSRS array station in Wonju which is consisted of 26 bore-hole stations. The seismic network of KIGAM is also linked to that of KEPRI(Korea Electric Power Research Institute)which is consisted of eight stations installed within and around the nuclear power plants. Owing to real-time data acquisition by telemetry, it became feasible to automatically locate hypocenters of the local events within fifteen minutes by computer data processing system, named KEMS(Korea Earthquake Monitoring System). Results of the hypocenter determination, together with observational data, are compiled and stored in the data base system. And they are published via web site whose URL is http://quake.kigam.re.kr KIGAM is also running t재 permanent geomagnetic stations installed in Daejun and Kyungju. The observed geomagnetic data are transmitted to Earthquake Research Centre in KIGAM by seismic network and compiled for the purpose of earthquake prediction research and other basic geophysical research.

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THE RELATIVE SUNSPOT NUMBERS IN 1996 (1996년 혹점 상대수)

  • Sim, Kyung-Jin
    • Publications of The Korean Astronomical Society
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    • v.12 no.1
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    • pp.23-33
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    • 1997
  • We have analyzed 223 data of the daily sunspot observations during the period of January 1 to December 31 in 1996 and present the daily relative sunspot numbers. During the 1996, the preliminary annual average of the relative sunspot numbers found to be 8.8 based on 3.7 distinct spots in a single group for 0.6 spot groups According to the appearance of 123 spot groups, our analysis shows that the mean life time of spot group is about 5 day and 5.8 hours. The proper conversion factor of the Korea Astronomy Observatory(KAO) derived from a comparison of one thousand one hundred and eighty observational sunspot numbers from 1992 to 1996 with those of international sunspot numbers is determined to be 1.17 instead of 0.97 which is in use.

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High Energy Observational Investigations of Supernova Remnants and their Interactions with Surroundings

  • Hui, Chung-Yue
    • Journal of Astronomy and Space Sciences
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    • v.30 no.3
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    • pp.127-132
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    • 2013
  • Here we review the effort of Fermi Asian Network (FAN) in exploring the supernova remnants (SNRs) with state-of-art high energy observatories, including Fermi Gamma-ray Space Telescope and Chandra X-ray Observatory, in the period of 2011- 2012. Utilizing the data from Fermi LAT, we have discovered the GeV emission at the position of the Galactic SNR Kes 17 which provides evidence for the hadronic acceleration. Our study also sheds light on the propagation of cosmic rays from their acceleration site to the intersteller medium. We have also launched an identification campaign of SNR candidates in the Milky Way, in which a new SNR G308.3-1.4 have been uncovered with our Chandra observation. Apart from the remnant, we have also discovered an associated compact object at its center. The multiwavelength properties of this X-ray source suggest it can possibly be the compact binary that survived a supernova explosion.

ASTROPHYSICS OF DUSTY STELLAR WINDS FROM AGB STARS

  • Suh, Kyung-Won
    • Journal of The Korean Astronomical Society
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    • v.47 no.6
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    • pp.219-233
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    • 2014
  • The main site of dust formation is believed to be the cool envelopes around AGB stars. Nearly all AGB stars can be identified as long-period variables (LPVs) with large amplitude pulsation. Shock waves produce by the strong pulsation and radiation pressure on newly formed dust grains drive dusty stellar winds with high mass-loss rates. IR observations of AGB stars identify various dust species in different physical conditions. Radio observations of gas phase materials are helpful to understand the overall properties of the stellar winds. In this paper, we review (i) classification of AGB stars; (ii) IR two-color diagrams of AGB stars; (iii) pulsation of AGB stars; (iv) dust around AGB stars including dusty stellar winds; (v) dust envelopes around AGB stars; (vi) mass-loss and evolution of AGB stars; and (vii) contribution of AGB dust to galactic environments. We discuss various observational evidences and their theoretical interpretations.

The fragmented asteroid 354P/LINEAR (2010 A2) captured by the K-GMT science program

  • Kim, Yoonyoung;Ishiguro, Masateru;Lee, Myung Gyoon
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.2
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    • pp.49.2-49.2
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    • 2017
  • With support from the K-GMT science program (PID: GN-2016B-Q-14), we conducted observations of active asteroid 354P/LINEAR (2010 A2) when it made its closest approach to Earth (i.e., the geocentric distance of 1.06 au on 2017 January 27-28). Taking advantage of the best observing geometry since the discovery, we obtained the first evidence for the rotational status of the largest fragment (~120 m in diameter), which was slowly rotating, that is, the rotational period of 11.36 hours. In addition, we succeed in direct imaging of 10 sub-fragments (~20 m in diameter or larger). Based on these new observational results, we conjecture that this active asteroid was created as a result of catastrophic collision among unknown asteroids. The details of this work are given in Astrophysical Journal Letters, 842, L23.

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A Study on the Manufacture of the Continuum Receiver System for Observing Cosmic Radio Waves (우주전파 관측용 연속파 수신시스템 제작에 관한 연구)

  • 서정빈;이창훈;임인성;한석태
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.9
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    • pp.67-75
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    • 1994
  • In this paper, we manufactured the continuum receiver system for observing the continuum waves emitted from the continuum sources with using the 14m radio-telescope. The receiving system measures the total power of the continuum sources and consists of DC-amplifier, beam-chopper system. Phase-Locked Loop(PLL) circuit, blanking circuit and its period selection circuit, V/F converter, and counter part which are capable of interfacing with the computer which is used for a data acquisition and making the radio-telescope track the source. We compared the obsevation results which use the existing DVM method with the observation results which use the continuum receiver to measure the total power of the sources. Moreover, by method of beam switching observation which uses newly installed beam chopper system. We can significantly improve the observational efficiency more than the existing position switching observation method.

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Spasmodic Torticollis Case Managed by Intraoral Balancing Appliance of FCST (FCST의 구강내 균형장치를 이용한 경추부 근긴장 이상증 증례보고)

  • Lee, Young Jun;Yin, Chang Shik
    • Journal of TMJ Balancing Medicine
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    • v.6 no.1
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    • pp.24-26
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    • 2016
  • To investigate the effects of the postural balance of TMJ using intraoral balancing appliance of functional cerebrospinal technique (FCST) combined acupuncture and manual medicine therapeutics in the treatment of congenital muscular torticollis. An idiopathic cervical dystonia case was managed with postural training with intraoral balancing appliance, combined with acupuncture and manual medicine therapeutics. Clinical assessment included radiography, Toronto Western Spasmodic Torticollis Rating Scale, and global clinical impression. Clinical improvement was observed over 5 months of treatment period. Clinical observational data on spasmodic torticollis provide an positive prospective for further investigation on the effect of FCST.

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A Correlation Study on Nurses′Subjective Perception and Their Effectiveness (간호원의 주관적 지각과 직무효율성간의 상관연구)

  • 정현숙
    • Journal of Korean Academy of Nursing
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    • v.3 no.2
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    • pp.101-109
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    • 1973
  • The present study in the view of humanistic psychology was attempted to seek the purpose of study, the relationship between nurses′working efficiency that measured by an observational working efficiency scale and their subjective perception. "Perceptual orientation scale"(Choy, Chung Hoon 1971) was administered to 100 nurses during the Period of May to July 1972, and the relationship with their ratings by their supervising head nurses. Educational background, ages, and their lengths of caller were compared with their subjective perceptions. All the relationship were calculated by the method of chi-squares and correlational coefficients. The results of this study are summarized as follow: 1. There is no significant relationship between nurses′subjective perceptions and their working ratings. 2. There is significant relationship between nurses′subjective perceptions and their educational backgrounds. 3. There is no significant relationship between nurses′subjective perceptions and their lengths of career. 4. There is no significant relationship between nurses′subjective perceptions and their ages. The results of the present study are interpreted to the sampled research group of this study and are not to be extended to any other groups.

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Design of the Low Energy Electron Detector for DITSAT-B

  • Park, Young-Wan-;Min, Kyoung-Wook
    • Bulletin of the Korean Space Science Society
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    • 1993.10a
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    • pp.22-22
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    • 1993
  • We developed the low energy electron detector (LEED) for KITSAT-B which was launched on September 26, 1998. The sensor head is mounted on the top of the satellite so that it can measure the precipitating electron flux along the Magnetic field line in the auroral zone at 820 km altitude. The detector system is composed of 4 parts : the electrostatic analyzer, the spira10on detector, the discriminator / Preamplifier, and the interface to the spacecraft. The analyzer limits the access to the spiraltron only to the electrons of certain energies which are determined by the electrostatic field across the two coaxial cylindrical analyzer plates. The energy spectrum of the detector in consideration is about 100 eV to 6.7 KeV, which is swept in 1.6 seconds and divided into 16 bins. It 81so is 1.6 second reset period after each swept, We will discuss the technical features of the system as well as the future observational schedule.

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