• Title/Summary/Keyword: H-space

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ON THE EXTRACTION OF OPTICAL ROTATION CURVES FOR SPIRAL GALAXIES

  • Sohn, Young-Jonh;Rhee, Myung-Hyun;Chun, Mun-Suk
    • Journal of Astronomy and Space Sciences
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    • v.15 no.1
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    • pp.27-38
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    • 1998
  • We discussed four different methods - the single, double and triple Gaussian fits, and the intensity weighted centroid fit - which extract rotation curves from several emis-sion lines(i.e. [OII], $H{\beta}$, [OIII], and $H{\alpha}$) of spiral galaxies. Spatial extents and the shapes of rotation curves derived through various methods applying to each emission lines of a sample galaxy UGC 11635 are all in a good agreement with one another. Linewidths of $H{\beta}$ and $H{\alpha}$ measure from rotation profiles are in a good agreement with $H{\alpha}$ linewidth of Courteau (1992). however, linewidths of [OII] seems to be much broader than $H{\alpha}$, and the profile of [OIII] does not follow the profile of $H{\alpha}$.

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TORSION IN THE COHOMOLOGY OF FINITE H-SPACES

  • Choi, Young-Gi
    • Journal of the Korean Mathematical Society
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    • v.39 no.6
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    • pp.963-973
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    • 2002
  • We study torsion phenomena in the integral cohomology of finite if-spaces X through the Eilenberg-Moore spectral sequence converging to H*($\Omega$X; Z$_{p}$). We also investigate how the difference between the Z$_{p}$-filtration length f$_{p}$(X) and the Z$_{p}$-cup length c$_{p}$(X) on a simply connected finite H-space X is reflected in the Eilenberg-Moore spectral sequence converging to H*($\Omega$X;Z$_{p}$). Finally we get the following result: Let p be an odd prime and X an n-connected finite H-space with dim QH* (X;Z$_{p}$) $\leq$ m. Then H*(X;Z) is p-torsion free if (equation omitted).tion omitted).

ANOTHER CHARACTERIZATION OF ROUND SPHERES

  • Lee, Seung-Won;Koh, Sung-Eun
    • Bulletin of the Korean Mathematical Society
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    • v.36 no.4
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    • pp.701-706
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    • 1999
  • A characterization of geodesic spheres in the simply connected space forms in terms of the ratio of the Gauss-Kronecker curvature and the (usual) mean curvature is given: An immersion of n dimensional compact oriented manifold without boundary into the n + 1 dimensional Euclidean space, hyperbolic space or open half sphere is a totally umbilicimmersion if the mean curvature $H_1$ does not vanish and the ratio $H_n$/$H_1$ of the Gauss-Kronecker curvature $H_n$ and $H_1$ is constant.

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PERFORMANCE TEST OF THE PROTO-MODEL OF SPACE INFRARED CRYOGENIC SYSTEM (우주용 적외선 냉각시스템 시험모델 성능 평가)

  • Lee, D.H.;Yang, H.S.;Nam, U.W.;Lee, S.;Jin, H.;Kim, D.L.;Pak, S.;Kim, B.H.;Park, S.J.
    • Publications of The Korean Astronomical Society
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    • v.21 no.2
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    • pp.61-66
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    • 2006
  • We have tested the performance of the Proto-model of Space Infrared Cryogenic System (PSICS), which is a small infrared camera, developed by Korea Astronomy and Space science Institute (KASI), Korea Basic Science Institute (KBSI), Korea Institute of Machinery and Materials (KIMM), and i3system co., as a cooperation project. The purpose of PSICS is to ensure a technology of small infrared cryogenic system for future development of space infrared (IR) cameras. PSICS consists of cryogenic part, IR sensor and electronics part, and optical part. The performance test of each part and the integrated system has been completed successfully. PSICS will be used as a guiding camera for ground-based IR telescopes and a test system for developing a space-borne instrument.

Poisson integrals contained in harmonic bergman spaces on upper half-space

  • Yi, Heung-Su
    • Communications of the Korean Mathematical Society
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    • v.12 no.1
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    • pp.51-58
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    • 1997
  • On the setting of the upper half-space, H of the euclidean n-space, we consider the question of when the Poisson integral of a function on the boundary of H is a harmonic Bergman function and here we give a partial answer.

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