• 제목/요약/키워드: STAR

검색결과 3,315건 처리시간 0.022초

ON STAR MOMENT SEQUENCE OF OPERATORS

  • Park, Sun-Hyun
    • 호남수학학술지
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    • 제29권4호
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    • pp.569-576
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    • 2007
  • Let $\cal{H}$ be a separable, infinite dimensional, complex Hilbert space. We call "an operator $\cal{T}$ acting on $\cal{H}$ has a star moment sequence supported on a set K" when there exist nonzero vectors u and v in $\cal{H}$ and a positive Borel measure ${\mu}$ such that <$T^{*j}T^ku$, v> = ${^\int\limits_{K}}\;{{\bar{z}}^j}\;{{\bar{z}}^k}\;d\mu$ for all j, $k\;\geq\;0$. We obtain a characterization to find a representing star moment measure and discuss some related properties.

TRIGGERED HIGH MASS STAR FORMATION

  • Kurtz, Stan
    • 천문학회지
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    • 제40권4호
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    • pp.137-140
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    • 2007
  • Triggered star formation is not a new idea - it's been around for at least the last 30 years. Although it has never disappeared from the scene, it seems to be enjoying something of a renaissance in recent years, in both observational and theoretical studies. Here we give a brief discussion of the background of triggered star formation, describe some of our own recent observational efforts in this regard, and briefly mention some initial conclusions that may be drawn.

Interaction of Supernova Remnants With the Ambient medium

  • DWARKADAS VIKRAM V.
    • 천문학회지
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    • 제34권4호
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    • pp.243-246
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    • 2001
  • We summarize various aspects of the interaction of supernova remnants (SNRs) with the ambient medium. We discuss the evolution' of SNRs in environments sculpted by the progenitor star, and summarize the factors on which this evolution depends. As a specific example, we consider the evolution of the medium around a 35 M$\bigodot$ star, and the interaction of the shock wave with this medium when the star explodes as a SN. We also discuss the interaction of Type Ia SNe with the ambient medium, especially the formation and growth of hydrodynamic instabilities.

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성형결합기 손실특성 개선에 관한 연구 (A Study on Loss Improvement of Star Coupler)

  • 박준오;정영철;이형종
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 추계학술대회 논문집 학회본부 C
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    • pp.603-604
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    • 2000
  • We investigate the low loss of star coupler which employs UV-written tapered waveguide and apply it to AWG. It exhibits the lower loss due to the gradual increase of the width of the UV-written taper waveguide than the conventional star coupler, which is improved by as much as 0.49dB.

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Precision Attitude Determination Design Using Tracker

  • Rhee, Seung-Wu;Kim, Zeen-Chul
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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    • pp.53-57
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    • 1998
  • Star tracker placement configuration is proposed and the properness of the placement configuration is verified for star tracker's sun avoidance angle requirement. Precision attitude determination system is successfully designed using a gyro-star tracker inertial reference system for a candidate LEO spacecraft. Elaborate kalman filter formulation for a spacecraft is proposed for covariance analysis. The covariance analysis is performed to verify the capability of the proposed attitude determination system. The analysis results show that the attitude determination error and drift rate error are good enough to satisfy the mission of a candidate spacecraft.

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초고압 지중선로 감시시스템 연구 (Surveillance System For Underground Power Transmission Lines)

  • 한기만;이광철;김충식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1993년도 하계학술대회 논문집 B
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    • pp.618-620
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    • 1993
  • This system using optical fiber provides various information about underground tunnel and power transmission lines-atmospheric temperature, humidity, oil pressure, flammable gas, cable behavior, and so on. To transmit various data and to keep reliability, optical MUXs are adopted. User can easily operate monitoring software by using GUI.

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ASYMPTOTIC FOR THE NUMBER OF STAR OPERATIONS ON ONE-DIMENSIONAL NOETHERIAN DOMAINS

  • Spirito, Dario
    • 대한수학회지
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    • 제58권5호
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    • pp.1239-1260
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    • 2021
  • We study the set of star operations on local Noetherian domains D of dimension 1 such that the conductor (D : T) (where T is the integral closure of D) is equal to the maximal ideal of D. We reduce this problem to the study of a class of closure operations (more precisely, multiplicative operations) in a finite extension k ⊆ B, where k is a field, and then we study how the cardinality of this set of closures vary as the size of k varies while the structure of B remains fixed.