• 제목/요약/키워드: mathematical structures

검색결과 935건 처리시간 0.023초

ON THE FINITENESS OF REAL STRUCTURES OF PROJECTIVE MANIFOLDS

  • Kim, Jin Hong
    • 대한수학회보
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    • 제57권1호
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    • pp.109-115
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    • 2020

  • Recently, Lesieutre constructed a 6-dimensional projective variety X over any field of characteristic zero whose automorphism group Aut(X) is discrete but not finitely generated. As an application, he also showed that X is an example of a projective variety with infinitely many non-isomorphic real structures. On the other hand, there are also several finiteness results of real structures of projective varieties. The aim of this short paper is to give a sufficient condition for the finiteness of real structures on a projective manifold in terms of the structure of the automorphism group. To be more precise, in this paper we show that, when X is a projective manifold of any dimension≥ 2, if Aut(X) does not contain a subgroup isomorphic to the non-abelian free group ℤ ∗ ℤ, then there are only finitely many real structures on X, up to ℝ-isomorphisms.

  • https://doi.org/10.4134/BKMS.b190084 인용 PDF KSCI

교사의 수학적 관념에 대한 연구 (A Study on Teachers' Conceptions of Mathematics)

  • 김용대
    • 한국수학교육학회지시리즈A:수학교육
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    • 제41권1호
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    • pp.35-44
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    • 2002

  • The purpose of this study is to estimate teachers'conceptions of mathematics through the conception on compositions of mathematical knowledge, the conception on structure of mathematical knowledge, the conception on status of mathematical knowledge, the conception on mathematical activity, and the conception of mathematics learning. This study reached the following conclusions: Most of teachers has more internal viewpoint than external viewpoint on the compositions, structures and status of mathematical knowledge, mathematical activity and mathematics learning.

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