• 제목/요약/키워드: Basis Set

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Examples of Quadratically Hyponormal Weighted Shifts

  • He, Wei;Li, Chunji
    • Kyungpook Mathematical Journal
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    • 제45권3호
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    • pp.413-421
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    • 2005
  • In this paper, we have a further discussion about quadratically hyponormal weighted shifts with weight sequence ${\alpha}:1,1,{\sqrt{a}},\left({\sqrt{b}},{\sqrt{c}},{\sqrt{d}}\right)^{\wedge}$ on the basis of sufficient conditions for positively quadratically hyponormal weighted shifts. We set examples of quadratically hyponormal weighted shifts with weight sequence of the above form, and also establish a general method for setting examples.

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Molecular Structure and Vibrational Spectra of Biphenyl in the Ground and the Lowest Triplet States. Density Functional Theory Study

  • 이상연
    • Bulletin of the Korean Chemical Society
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    • 제19권1호
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    • pp.93-98
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    • 1998
  • The molecular geometries and harmonic vibrational frequencies of biphenyl in the ground and the first excited triplet states have been calculated using the Hartree-Fock and Becke-3-Lee-Yang-Parr (B3LYP) density functional methods with 6-31G* basis set. Structural change occurs from a twisted benzene-like to a planar quinone-like form upon the excitation to the first excited state. Scaled harmonic vibrational frequencies for the ground state obtained from the B3LYP calculation show good agreement with the available experimental data. A few vibrational fundamentals for both states are newly assigned based on the B3LYP results.

Computational Study on the Isomers of Cyanopolyacetylenes H(C$\equiv$C)nC$\equiv$N (n=1-3)

  • 이석진;박성우;이성율
    • Bulletin of the Korean Chemical Society
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    • 제21권7호
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    • pp.734-740
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    • 2000
  • Density functional theory calculations are presented for the geometrical isomers of the cyanopolyacetylenes H(C≡C)n,,C≡N (n = I-3). The structures, hartmonic frequencies and dipole moments are computed, employing the 6-311G** basis set. The ener gies of barrier to isomerization (exchange of carbon and nitrogen atoms) are also computed in order to estimate the stability of the isomers in interstellar space.

Molecular Structure and Vibrational Spectra of 9-Fluorenone Density Functional Theory Study

  • 이상연;부봉현
    • Bulletin of the Korean Chemical Society
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    • 제17권8호
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    • pp.760-764
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    • 1996
  • The molecular geometry and vibrational frequencies of 9-fluorenone have been calculated using the Hartree-Fock and Becke-3-Lee-Yang-Parr(B3LYP) density functional methods with 6-31G* basis set. Harmonic vibrational frequencies obtained from the B3LYP calculation show good agreement with the available experimental data. A few vibrational fundamentals are newly assigned based on the B3LYP results. The B3LYP calculation is reconfirmed to be useful in the assignment of the fundamental vibrational frequencies.

Theoretical Studies on the Potential Energy Profiles for Proton Transfer Reaction in Formamide Dimer

  • Young Shik Kong;Mu Shik Jhon
    • Bulletin of the Korean Chemical Society
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    • 제10권6호
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    • pp.488-491
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    • 1989
  • Theoretical studies on the proton transfer reaction in a formamide dimer have been done by Ab initio SCF calculation. In this study, we have shown several effects on the potential energy profile of the proton transfer in a formamide dimer, such as the effect of a basis set, the effect of a geometry optimization, and the effect of a distance between proton-donor and proton-acceptor.

Structures and Spectroscopic Properties of $OC_nO$ (n=2-6): Density Functional Theory Study

  • 김경환;이보순;이성열
    • Bulletin of the Korean Chemical Society
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    • 제19권5호
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    • pp.553-557
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    • 1998
  • Density functional theory calculations are reported for the carbon clusters bonded with two oxygen atoms $OC_No$ (n=2-6). The structures, vibrational frequencies and dipole moments are computed by BLYP theory with the 6-311G* basis set. Good agreement is obtained between the computed and experimentally observed properties. The ground states of these molecules are shown to be linear. Cyclic structures with higher energy are also predicted.

Conformational Study of Pseudo-Proline Dipeptide in the Gas Phase and Solutions

  • Park, Hae-Sook;Kang, Young-Kee
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.158.1-158.1
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    • 2003
  • We report here the results on N-acetyl-N"-methylamide of oxazolidine (Ac-Oxa-NHMe) calculated using the ab initio molecular orbital method with the self-consistent reaction field (SCRF) theory at the HF level of theory with the 6-31 +G(d) basis set. The displacement of the $\gamma$-$CH_2$ group in proline ring by oxygen atom has affected the structure of proline, cis-trans equilibrium, and rotational barrier. The up-puckered structure is found to be prevalent for the trans conformers of the Oxa amide. (omitted)

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Axial Power Distribution Calculation Using a Neural Network in the Nuclear Reactor Core

  • Kim, Y. H.;K. H. Cha;Lee, S. H.
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1997년도 추계학술발표회논문집(1)
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    • pp.58-63
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    • 1997
  • This paper is concerned with an algorithm based on neural networks to calculate the axial power distribution using excore defector signals in the nuclear reactor core. The fundamental basis of the algorithm is that the detector response can be fairly accurately estimated using computational codes. In other words, the training set, which represents relationship between detector signals and axial power distributions, for the neural network can be obtained through calculations instead of measurements. Application of the new method to the Yonggwang nuclear power plant unit 3 (YGN-3) shows that it is superior to the current algorithm in place.

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A NOTE ON g-SEMISIMPLICITY OF A FINITE-DIMENSIONAL MODULE OVER THE RATIONAL CHEREDNIK ALGEBRA OF TYPE A

  • Gicheol Shin
    • 충청수학회지
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    • 제36권2호
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    • pp.77-86
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    • 2023
  • The purpose of this paper is to show that a certain finite dimensional representation of the rational Cherednik algebra of type A has a basis consisting of simultaneous eigenvectors for the actions of a certain family of commuting elements, which are introduced in the author's previous paper. To this end, we introduce a combinatorial object, which is called a restricted arrangement of colored beads, and consider an action of the affine symmetric group on the set of the arrangements.

방사 기저 함수 신경망을 이용한 3차원 얼굴인식 (3D face recognition based on radial basis function network)

  • 양욱일;손광훈
    • 대한전자공학회논문지SP
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    • 제44권2호
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    • pp.82-92
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    • 2007
  • 본 논문에서는 3차원 얼굴인식을 위한 방사 기저 함수 신경망 기반의 새로운 전역적 형태 특징과 그 특징을 추출하는 방법을 제안한다. 방사 기저 함수 신경망은 방사 기저 함수들의 가중합으로써, 얼굴 형태 정보의 비선형성을 방사 기저 함수의 선형합으로 잘 표현한다. 이 논문에서는 얼굴의 가로 방향 프로파일을 학습된 방사 기저 함수 신경망에 적용시켰을 때 생성되는 가증치를 새로운 전역적 형태 특징으로 제안한다. 제안하는 전역적 형태 특징의 경우 국소적 특징의 특성을 가지며, 일반적인 전역적 특징의 특성인 특징의 복잡도도 감소시킨다. 100명의 데이터베이스 영상과 100명에 대한 서로 다른 3개의 포즈를 포함하는 300개의 테스트 영상을 이용한 실험에서 제안하는 전역적 형태 특징과 은닉 마르코프 모델을 이용한 특징 비교를 통해서 94.7%의 인식률을 얻었다.