• 제목/요약/키워드: cubic field

검색결과 235건 처리시간 0.023초

DETERMINATION OF CLASS NUMBERS OR THE SIMPLEST CUBIC FIELDS

  • Kim, Jung-Soo
    • 대한수학회논문집
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    • 제16권4호
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    • pp.595-606
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    • 2001
  • Using p-adic class number formula, we derive a congru-ence relation for class numbers of the simplest cubic fields which can be considered as a cubic analogue of Ankeny-Artin-Chowlas theo-rem, Furthermore, we give an elementary proof for an upper bound for the class numbers of the simplest cubic fields.

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UNIT GROUPS OF QUOTIENT RINGS OF INTEGERS IN SOME CUBIC FIELDS

  • Harnchoowong, Ajchara;Ponrod, Pitchayatak
    • 대한수학회논문집
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    • 제32권4호
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    • pp.789-803
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    • 2017
  • Let $K={\mathbb{Q}}({\alpha})$ be a cubic field where ${\alpha}$ is an algebraic integer such that $disc_K({\alpha})$ is square-free. In this paper we will classify the structure of the unit group of the quotient ring ${\mathcal{O}}_K/A$ for each non-zero ideal A of ${\mathcal{O}}_K$.

Integral Hellmann-Feynman Approach에 의한 KNiF$_3$의 Cubic Crystal Field Splitting 10 Dq의 계산 (Calculation of the Cubic Crystal Field Splitting 10 Dq in KNiF$_3$. An Integral Hellmann-Feynman Approach)

  • 김호징;김희준
    • 대한화학회지
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    • 제17권6호
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    • pp.395-405
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    • 1973
  • Integral Hellmann-Feynman formula를 사용하여 $KNiF_3$의 cubic crystal splitting 10Dq를 first principle로부터 계산하였다. Covalency parameter들과 필요한 적분치들은 Sugano와 Shulman의 계산치를 사용하였다. 계산치 7100$cm^{-1}$는 실험치 7250$cm^{-1}$와 대단히 잘 일치하였다. 고차섭동에너지 보정치는 10 Dq 자체와 같은 order of magnitude를 가지며 따라서 first principle로부터 10 Dq를 계산하는데 있어서 반드시 고려되어야 할 몫이라는 것을 발견하였다. 또한 point charge potential이 crystal field potential의 압도적인 부분을 차지하는 것을 발견하였다.

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RESTRICTION OF SCALARS AND CUBIC TWISTS OF ELLIPTIC CURVES

  • Byeon, Dongho;Jeong, Keunyoung;Kim, Nayoung
    • 대한수학회지
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    • 제58권1호
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    • pp.123-132
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    • 2021
  • Let K be a number field and L a finite abelian extension of K. Let E be an elliptic curve defined over K. The restriction of scalars ResKLE decomposes (up to isogeny) into abelian varieties over K $$Res^L_KE{\sim}{\bigoplus_{F{\in}S}}A_F,$$ where S is the set of cyclic extensions of K in L. It is known that if L is a quadratic extension, then AL is the quadratic twist of E. In this paper, we consider the case that K is a number field containing a primitive third root of unity, $L=K({\sqrt[3]{D}})$ is the cyclic cubic extension of K for some D ∈ K×/(K×)3, E = Ea : y2 = x3 + a is an elliptic curve with j-invariant 0 defined over K, and EaD : y2 = x3 + aD2 is the cubic twist of Ea. In this case, we prove AL is isogenous over K to $E_a^D{\times}E_a^{D^2}$ and a property of the Selmer rank of AL, which is a cubic analogue of a theorem of Mazur and Rubin on quadratic twists.

GALOIS STRUCTURES OF DEFINING FIELDS OF FAMILIES OF ELLIPTIC CURVES WITH CYCLIC TORSION

  • Jeon, Daeyeol
    • 충청수학회지
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    • 제27권2호
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    • pp.205-210
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    • 2014
  • The author with C. H. Kim and Y. Lee constructed infinite families of elliptic curves over cubic number fields K with prescribed torsion groups which occur infinitely often. In this paper, we examine the Galois structures of such cubic number fields K for the families of elliptic curves with cyclic torsion.

유한요소법을 이용한 과도 선형 동탄성 해석 (Transient Linear Elastodynamic Analysis by the Finite Element Method)

  • 황은하;오근
    • 한국산업융합학회 논문집
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    • 제12권3호
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    • pp.149-155
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    • 2009
  • A new finite element equation is derived by applying quadratic and cubic time integration scheme to the variational formulation in time-integral for the analysis of the transient elastodynamic problems to increase the numerical accuracy and stability. Emphasis is focused on methodology for cubic time integration scheme procedure which are never presented before. In this semidiscrete approximations of the field variables, the time axis is divided equally and quadratic and cubic time variation is assumed in those intervals, and space is approximated by the usual finite element discretization technique. It is found that unconditionally stable numerical results are obtained in case of the cubic time variation. Some numerical examples are given to show the versatility of the presented formulation.

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