• 제목/요약/키워드: K-space

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Seasonal Variations of the Zodiacal Light toward the Ecliptic Poles at the Infrared Wavelengths

  • Pyo, Jeonghyun;Kim, Il-Joong;Jeong, Woong-Seob;Lee, Dae-Hee;Moon, Bongkon;Park, Youngsik;Park, Sung-Joon;Park, Won-Kee;Lee, Duk-Hang;Nam, Uk-Won;Han, Wonyong;Seon, Kwang-Il;Matsumoto, Toshio;Kim, Min Gyu;Lee, Hyung Mok
    • 천문학회보
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    • 제41권1호
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    • pp.47.3-48
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    • 2016
  • The zodiacal light (ZL), combination of the sunlight scattered by and the infrared light emitted by the interplanetary dust (IPD) particles, changes with time due to the asymmetric distribution of the particles with respect to the Earth's orbit. Especially, the variation of the ZL brightness toward the ecliptic poles are useful to probe the properties of the global distribution of the IPD because we can evade the effect of the small scale structures, such as the asteroidal dust bands. The ecliptic poles are frequently visited by the infrared (IR) space telescopes owing to their sun-synchronous orbits or for specific purposes. We collect and analyze the observations toward the ecliptic poles by COBE/DIRBE, AKARI, and MIRIS, covering the wavelengths from about 1 to $25{\mu}m$. The observed seasonal variations of the ZL are modeled with a simple IPD cloud model to derive cloud parameters. The parameters are compared with those of the empirical cloud models by Kelsall et al. (1998) and Kondo et al. (2016), and the discrepancies are discussed.

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Some Properties on Intuitionistic Fuzzy Metric Space

  • Park, Jong-Seo;Kwun, Young-Chel;Park, Jin-Han
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제10권2호
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    • pp.152-156
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    • 2010
  • We define some terminologies on intuitionistic fuzzy metric space and prove that the topology generated by any intuitionistic fuzzy metric space is metrizable. Also, we show that if the intuitionistic fuzzy metric space is complete, then the generated topology is completely metrizable, a Baire space, and that an intuitionistic fuzzy metric space is precompact if and only if every sequence has a Cauchy subsequence.

Observation Planning Software for FIMS

  • Park, J.H.;K.I. Seon;I.S. Yuk;U.W. Nam;W. Han;K.S. Ryu;K.W. Min;J. Seon;J. Edelstein
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
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    • 한국우주과학회 2000년도 한국우주과학회보 제9권1호
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    • pp.49-49
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    • 2000
  • No Abstract, See Full Text

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Baseline Design and Performance Analysis of Laser Altimeter for Korean Lunar Orbiter

  • Lim, Hyung-Chul;Neumann, Gregory A.;Choi, Myeong-Hwan;Yu, Sung-Yeol;Bang, Seong-Cheol;Ka, Neung-Hyun;Park, Jong-Uk;Choi, Man-Soo;Park, Eunseo
    • Journal of Astronomy and Space Sciences
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    • 제33권3호
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    • pp.211-219
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    • 2016
  • Korea's lunar exploration project includes the launching of an orbiter, a lander (including a rover), and an experimental orbiter (referred to as a lunar pathfinder). Laser altimeters have played an important scientific role in lunar, planetary, and asteroid exploration missions since their first use in 1971 onboard the Apollo 15 mission to the Moon. In this study, a laser altimeter was proposed as a scientific instrument for the Korean lunar orbiter, which will be launched by 2020, to study the global topography of the surface of the Moon and its gravitational field and to support other payloads such as a terrain mapping camera or spectral imager. This study presents the baseline design and performance model for the proposed laser altimeter. Additionally, the study discusses the expected performance based on numerical simulation results. The simulation results indicate that the design of system parameters satisfies performance requirements with respect to detection probability and range error even under unfavorable conditions.