• 제목/요약/키워드: (k, s)-generalization

검색결과 406건 처리시간 0.029초

ON THE SYNGE'S THEOREM FOR COMPLEX FINSLER MANIFOLDS

  • Won, Dae-Yeon
    • 대한수학회보
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    • 제41권1호
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    • pp.137-145
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    • 2004
  • In [13], we developed a theory of complex Finsler manifolds to investigate the global geometry of complex Finsler manifolds. There we proved a version of Bonnet-Myers' theorem for complex Finsler manifolds with a certain condition on the Finsler metric which is a generalization of the Kahler condition for the Hermitian metric. In this paper, we show that if the holomorphic sectional curvature of M is ${\geq}\;c^2\;>\;0$, then M is simply connected. This is a generalization of the Synge's theorem in the Riemannian geometry and the Tsukamoto's theorem for Kahler manifolds. The main point of the proof lies in how we can circumvent the convex neighborhood theorem in the Riemannian geometry. A second variation formula of arc length for complex Finsler manifolds is also derived.

남성 패션에 표현된 문화 꼴라쥬 현상 (Cultural Collage in Men's Fashion)

  • 이민선
    • 복식문화연구
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    • 제13권3호
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    • pp.469-480
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    • 2005
  • The purpose of this study is to analyze the meaning and the value of the cultural collage expressed in men's fashion. As for the research methodology, literary research was under taken to study psychoanalytical and socioeconomic contexts in which cultural collage has been formed. In addition, demonstrative studies in men's fashion were undertaken through the analysis of pictures. The cultural collage is defined as a phenomena of making creativity by combining cultures which have no relevance. In psychological and sociological aspects, the rise of the cultural collage is caused by multinational corporation, pluralization of identity, information society, consumer oriented production, consumer society and inundation of kitsch. On the basis of the characteristics and social backgrounds of cultural collage, the aesthetic values of men's fashion can be explained by pluralism de-generalization and relativity.

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A GENERALIZATION OF STONE'S THEOREM IN HILBERT $C^*$-MODULES

  • Amyari, Maryam;Chakoshi, Mahnaz
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제18권1호
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    • pp.31-39
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    • 2011
  • Stone's theorem states that "A bounded linear operator A is infinitesimal generator of a $C_0$-group of unitary operators on a Hilbert space H if and only if iA is self adjoint". In this paper we establish a generalization of Stone's theorem in the framework of Hilbert $C^*$-modules.

초등학교 6학년 수학영재학생들의 학습유형에 따른 일반화 및 정당화 비교 분석 (Comparative Analysis of Generalization and Justification of the Mathematically Gifted 6th Graders by Learning Styles)

  • 유미경;장혜원
    • 대한수학교육학회지:수학교육학연구
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    • 제27권3호
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    • pp.391-410
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    • 2017
  • 본 연구는 학습유형이 상이한 초등학교 6학년 수학영재학생들의 일반화 및 정당화의 특징을 분석함으로써 학습유형에 따른 개별화 지도방안에 대한 교수학적 시사점을 도출하는 것을 목적으로 한다. 이를 위해, 초등학교 6학년 수학영재학생 3명의 학습유형을 판별하고 주어진 수학적 과제를 해결하는 수행과정을 추적 관찰하였다. 학생들에게는 지필환경과 함께 지오지브라를 활용한 동적기하환경이 제공되었으며, 학생들이 작성한 활동지, 지오지브라의 활동이 기록된 학생의 산물, 두 연구자가 관찰하며 작성한 현장관찰일지, 과제 탐구 후 개별면담 등을 통해 자료를 수집하여 질적 분석을 실시하였다. 그 결과, 초등학교 6학년 수학영재학생들의 일반화 특성은 다양하게 나타났으나 그에 비해 정당화 수준은 동일한 것으로 드러났다. 또한, 학습유형에 따라 학습 환경에 대한 선호도의 차이를 보였다. 이러한 연구 결과를 바탕으로 수학영재학생들의 학습유형에 따른 개별화 지도방안에 대해 제안하였다.

ON THE BONNET′S THEOREM FOR COMPLEX FINSLER MANIFOLDS

  • Won, Dae-Yeon
    • 대한수학회보
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    • 제38권2호
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    • pp.303-315
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    • 2001
  • In this paper, we investigate the topology of complex Finsler manifolds. For a complex Finsler manifold (M, F), we introduce a certain condition on the Finsler metric F on M. This is a generalization of Kahler condition for the Hermitian metric. Under this condition, we can produce a Kahler metric on M. This enables us to use the usual techniques in the Kahler and Riemannian geometry. We show that if the holomorphic sectional curvature of $ M is\geqC^2>0\; for\; some\; c>o,\; then\; diam(M)\leq\frac{\pi}{c}$ and hence M is compact. This is a generalization of the Bonnet\`s theorem in the Riemannian geometry.

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CERTAIN HYPERGEOMETRIC IDENTITIES DEDUCIBLE BY USING THE BETA INTEGRAL METHOD

  • Choi, Junesang;Rathie, Arjun K.;Srivastava, Hari M.
    • 대한수학회보
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    • 제50권5호
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    • pp.1673-1681
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    • 2013
  • The main objective of this paper is to show how one can obtain eleven new and interesting hypergeometric identities in the form of a single result from the old ones by mainly employing the known beta integral method which was recently introduced and used in a systematic manner by Krattenthaler and Rao [6]. The results are derived with the help of a generalization of a well-known hypergeometric transformation formula due to Kummer. Several identities including one obtained earlier by Krattenthaler and Rao [6] follow as special cases of our main results.

STELLAR MAGNETIC ACTIVITY AND LONG TERM LUMINOSITY VARIATIONS OF LATE TYPE STARS.: I. ON GENERALIZATION OF ${\ddot{O}}PIK'S$ CONVECTION THEORY TO A ROTATING MEDIUM

  • Park, Chang-Bum;Yun, Hong-Sik;Lee, Jeong-Woo
    • 천문학회지
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    • 제18권2호
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    • pp.86-99
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    • 1985
  • A generalization of the original ${\ddot{O}}pik's$ cellular convection theory has been made to accomodate a rotating convective medium. With the use of the formulation, a set of rotating model envelopes of the sun and late type main sequence stars have been constructed under three different rotation periods. Their thermal structures are presented and characteristics of their convection are discussed in the context of stellar dynamo. In the present study it is noted that the rotational angular velocity increases in wards with depth, and its increase turns out to be about 6% at the bottom of the solar convection zone.

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A Generalization of S. P. Singh's T-invariant Point Theorem to Approximation Theory

  • Cho, Yeol Je
    • 한국수학교육학회지시리즈A:수학교육
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    • 제18권1호
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    • pp.21-23
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    • 1980
  • In [3], an extension of B. Brosowski s T-invariant Point Theorem is given where the linearity of the function and the convexity of the set are relaxed. In this paper, our main purpose is to generalize S. P. Singh's T-invariant Point Theorem to Approximation Theory.

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