• Title/Summary/Keyword: 행성

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Olivine Synthesis Using Stainless Steel Tube (스테인리스강관을 이용한 감람석 합성)

  • Gi Young Jeong
    • Korean Journal of Mineralogy and Petrology
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    • v.36 no.4
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    • pp.337-343
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    • 2023
  • Olivine is a complete solid solution of fayalite and forsterite that is abundant in Earth and extraterrestrial materials such as rocky planets, meteorites, asteroids, and interplanetary dust. Due to the wide range of olivine compositions, diverse olivine standards are required for quantitative mineralogical analysis of olivine-bearing materials. Olivine standards were synthesized using an electric furnace and stainless steel tubes at temperatures ranging from 1000~1100 ℃. Overall, olivine was synthesized covering the full range of composition, with some synthetic impurities and unreacted material. The synthesized olivine showed a linear increase in the unit cell dimension in proportion to the molar ratio of fayalite in the starting materials, and the diffraction intensity was consistent with that of natural olivine. However, iron-rich synthetic olivine samples tend to have a higher content of impurity, suggesting that not all synthetic olivine can be used as a standard material yet, and improvements in the synthesis process, such as using high purity starting materials and control of reaction time and temperature, are required.

[ $^{99m}Tc-DISIDA$ ] Scintigraphic Diagnosis Of Extrahepatic Hepatocellular Carcinoma Metastasis : Comparison with Primary Hepatocellular Carcinoma ($^{99m}Tc-DISIDA$ 신티그래피를 이용한 간세포암 간외 전이의 진단 : 원발 간세포암과의 비교)

  • Chung, Soo-Kyo;Kim, Sung-Hoon;Baik, Joon-Hyun;Kim, Young-Joo;Chun, Kyung-Ah;Park, Seog-Hee;Bahk, Yong-Whee;Shin, Kyung-Sub
    • The Korean Journal of Nuclear Medicine
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    • v.29 no.4
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    • pp.484-491
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    • 1995
  • It is well known that hepatobiliary agent are taken up by metastatic hepatocellular carcinoma(HCC) as well as primary HCC. But the reported cases of the extrahepatic metastasis of HCC diagnosed by hepatobiliary scintigraphy are for the most part hematogenous ones. The relation of the uptake pattern of hepatobiliary agent in the primary and metastatic HCC is also still remains unknown. So we undertook this study to evaluate the relation of the hepatobiliary scintigraphic patterns of primary and metastatic HCC with different metastatic routes. Nine patients with primary HCC and twelve cases of metastatic HCC including four lung metastases, one bone metastasis, one right atrial metastasis, one peritoneal wall metastasis, and five lymph node metastases were studied with $^{99m}Tc-DISIDA$ scintigraphy. The images were taken on 10, 30 minutes, 1, 2, 4-6 hours. The overall detection rates of hematogenous metastases(lung and bone) is 60%(3 of 5), direct metastasis(right atrium and peritoneal wall), 100%(2 of 2) and lymphatic metastases, 0%(0 of 5). In four of five metastatic cases demonstrated with hepatobiliary scintigraphy, biliary agent is also taken up by primary HCC lesions. And the appearing time of the radioactivity in the direct metastatic HCC lesioin is same as that of primary HCC and in the cases of hematogenous metastasis, earlier than that of primary HCC. Hepatobiliary scintigraphy is more useful in the diagnosis of the metastatic HCC than primary HCC, in the cases of hematogenous and direct metastasis.

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International Legal Status of U.S. Citizens Property Right to Space Resources (미국 국내법령상 우주자원 소유권의 국제법상 의의)

  • Shin, Hong-Kyun
    • The Korean Journal of Air & Space Law and Policy
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    • v.33 no.2
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    • pp.419-442
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    • 2018
  • Space Treaty Article 2 stipuates non-appropriation by sovereignty, and in any other means. Interpretative controversies has continued as regards the meaning of any other means. It is not clear whether appropriation by private entity is also prohibited or not. Furthermore, the controverse around the binding force of Article 1 has made worse the controversy regarding such appropriation. U.S. Congress has enacted the law regarding the space resouce mining in 2015. Its main purpose is to alleviate legal unstability which U.S, private companies have faced, and it provides some provisions regarding private rights about space resources. Original bill, H.R. 1508 included the property right. Amendment to the bill is to ensure that an "asteroid resource utilization activity" is inter-preted as on a single asteroid and not on any asteroid. The use of the word "in situ" in defining space resources simply means resources in place in outer space; but any such resource within or on an asteroid would need to be "obtained" in order to confer a property right. The use of the word "in situ" in merely defining a space resource in the bill is not equivalent to claiming sovereignty or control over celestial bodies or portions of space. Further, there is clear Congressional direction in the bill that the President is only to encourage space resources exploration and utilization, including lowering barriers to such activity, "consistent with" and "in accordance with" US international obligations. Federal courts are granted original jurisdiction over entities defined in ${\S}$ 51301(4) and in-situ asteroid resources that have been removed from an asteroid by such entities. Federal courts are not granted jurisdiction over outer space, the Moon, other celestial bodies, or the asteroid from which the in-situ natural resource was removed. It is said that the Space Resource Utilization Exploration Act of 2015, talked about the rights of private players to own-kind of a "finders keepers" law.

Design of a Wheel Test Bed for a Planetary Exploration Rover and Driving Experiment (행성탐사 로버 휠 테스트 베드 설계 및 주행 실험)

  • Kim, Kun-Jung;Kim, Seong-Hwan;Yu, Kee-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.4
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    • pp.372-377
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    • 2015
  • In this paper, the consideration factors that affect the actual driving of a rover wheel was examined based on the wheel-terrain model. For the evaluation of driving performance in a real environment, the test bed of the rover wheel consists of the driving part of the wheel and sensing part of the various parameters was designed and assembled. Using the test bed, the preliminary driving experiment concerning the slip ratio, sinkage, and friction force according to the rotational velocity and the shape of the wheel were carried out and evaluated. The wheel test bed and the experiment results are expected to contribute to finding the optimal result in the designing of the wheel shape and the planning of the driving conditions through further study.

Creating the Future: The Direction and Strategy for Advanced Korea(A-KOREA) (미래창조 선도국가(A-KOREA)의 방향성과 추진전략)

  • Ha, W.G.;Choi, M.S.;Kim, S.M.
    • Electronics and Telecommunications Trends
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    • v.28 no.2
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    • pp.115-131
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    • 2013
  • 본고에서는 인류문명의 탄생과 발전의 원동력을 커뮤니케이션 혁명에 두고, 인류역사를 언어문명, 문자문명, 인쇄문명 그리고 초연결 창조문명으로 구분한다. 이러한 전제하에서, 21세기 초엽에 우리가 목격하고 있는 '편재하는 인터넷 시대'를 초연결 창조문명 태동기로 본다. 본고의 목적은 이러한 창조문명 시대의 도래를 배경으로 미래창조국가의 프레임과 추진 전략을 고찰하는 데 있다. 이를 위해 초연결 융합창조망을 단계별로 구축하여 국가자원을 보다 잘 연결하고(Connected), 과학기술과 산업 그리고 인프라 등을 융합하여(Convergent), 새로운 성장동력과 국민복지를 창출하는(Creative) $C^3$ 기반 미래창조 선도국가(Advanced Korea for All: A-KOREA)의 방향성을 제시한다. 또한 'A-KOREA'를 실현하기 위해 기반 형성 단계, 도약 단계, 성숙 단계. 행성 단계로 구분한 후 각 단계별 추진 전략을 도출한다. 마지막으로 인류 신문명 시대의 미래창조 선도국가로 진입하기 위한 국가리더십의 표출 경로를 정리하여 보았다.

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S/W DEVELOPMENT OF HIGH PRECESION EPHEMERIS(I) (고정도 천체력 S/W 개발(I))

  • 안영숙;신종섭;박필호;박온광;이정숙
    • Journal of Astronomy and Space Sciences
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    • v.10 no.2
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    • pp.152-162
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    • 1993
  • We developed the S/W which calculate the Planetary and the Moon ephemerides. The ephemeris of the Solar system objects was obtained from a simultaneous numerical integration of the equations of motion for the nine planets and the Moon. The mathematical model includes contributions from (1) point-mass interactions (2) figure effect (3) earth tides (4) the orientations of the Earth and the Moon. The calculated ephemerides are compared with DE200 data produced by JPL (Jet Propulsion Laboratory).

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The relationship between the auroral electrojet, interplanetary magnetic field and the magnetic storm

  • 박윤경;문가희;안병호
    • Bulletin of the Korean Space Science Society
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    • 2003.10a
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    • pp.80-80
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    • 2003
  • 서브스톰이 진행될 때 극지방의 지자기 교란은 대류 제트 전류와 서브스톰 전류 쐐기로 구성되는 오로라 제트 전류에 기인한다. 이들은 전기장 강화를 뜻하는 AU 지수와 전기 전도도 강화를 뜻하는 AL 지수로 나타낼 수 있다. 이들 AU, AL 지수와 자기폭풍의 정도를 나타내는 Dst 지수와의 상관관계를 구해봄으로써 서브스톰이 자기폭풍의 형성에 어떻게 기여하는지 조사하였다. 이를 위하여 월별 누적 AU, 누적 │AL│ 값을 구한 뒤 월별 누적 Dst 와의 상관관계를 구하였다. 한편 IMF(Interplanetary Magnetic Field)의 남쪽 자기장 성분으로부터 지구 자기장 내에 강력한 전기장이 형성되어 자기폭풍을 형성한다는 견해가 있다. 전기장 E=V(태양풍 속도)$\times$Bs(IMF의 남쪽 자기장 성분)으로 나타낼 수 있으므로 이로부터 구한 월별 누적 전기장과 누적 Dst 값을 비교해 봄으로써 자기권 대류가 자기폭풍 형성에 어느 정도 기여하는지 조사하였다. 본 연구를 위하여 1966년부터 1987년까지 20년간의 AE(AU, AL) 지수를 이용하였으며 IMF 자료는 ACE 위성이 제공하는 행성간 자기장 자료로 1997년부터 2002년까지의 자료를 이용하였다. 본 연구의 결과는 현재 논쟁이 되고 있는 storm-substorm의 인과관계를 보다 잘 규명할 것으로 기대된다.

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SPECTROSCOPY OF PLANETS AND COMETS (거대 행성들과 혜성들의 분광학)

  • KIM SANG JOON;LEE YOUNG SIEK;YI YU;KIM YOUNG HA
    • Publications of The Korean Astronomical Society
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    • v.15 no.spc1
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    • pp.31-38
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    • 2000
  • We have presented detected molecules, atoms, radicals, ions, and dimers in the atmospheres of planets and comets from Earth-based and spaceborne observatories during the last 3 decades. We have reviewed spectroscopic studies on the auroral emissions and air glows of the giant planets, and briefly summarized spectroscopic observations of dimers in the atmospheres of the giant planets and Titan. In particular, we highlighted the recent detections of new molecular emissions and absorptions in the spectra of the giant planets, Titan, and recent bright comets from spaceborne or ground-based observatories. We also reviewed current models and theories of the origin and evolution of the solar system, and implications of isotopic ratios in these atmospheres.

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Educational activities at DOAO using 1-m telescope in NYSC

  • Kwon, Sun-Gill;Kang, wonseok;Kim, Taewoo;Lee, Sang-Gak
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.2
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    • pp.45.2-45.2
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    • 2016
  • 국립고흥청소년우주체험센터(이하 우주체험센터)에서는 2013년부터 덕흥천문대를 활용한 프로그램을 청소년에게 제공하고 있고, 2016년부터는 1m망원경을 활용한 연구 또한 동시에 진행하고 있다. 우주체험센터에서는 청소년 및 일반대중을 위해 덕흥 천문대를 활용하여 우주과학교실, 별잔치, 대학생 현장실습, 우주과학동아리 등의 사업을 운영하고 있다. 본 발표에서는 과거부터 현재까지 운영해온 사업에 대한 소개 및 공유는 물론, 올해부터 진행 중인 1m망원경을 활용한 천문연구에 대한 소개도 진행할 예정이다. 현재 NYSC 1m망원경을 이용하여 외부은하의 초신성 모니터링과 함께 외계행성 별표면 통과현상을 관측하여 분석중이다. 또한, 2016년 9월부터는 관측제안서를 통한 외부 공개관측이 진행되며 전문가 이외에도 실제 청소년 관측 제안서에 멘토 역할을 하는 등 실질적 교육을 하고자 한다.

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Micromagnetism (미세자기학)

  • Yu, Yong-Jae
    • 한국지구물리탐사학회:학술대회논문집
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    • 2009.10a
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    • pp.107-109
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    • 2009
  • Micromagnetism explores magnetic configurations in nano-scales to visualize the details of magnetic domain structures, and also can produce snapshots of complex remanence or other magnetic states. The particle shape has a profound effect on the magnetic hysteresis. For instance, octahedral magnetite showed higher coercivity and squareness than cubic magnetite.

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