• 제목/요약/키워드: Energies

검색결과 2,433건 처리시간 0.028초

A NEW CONSTRUCTION OF BIENERGY AND BIANGLE IN LORENTZ 5-SPACE

  • Korpinar, Talat;Unluturk, Yasin
    • 호남수학학술지
    • /
    • 제43권1호
    • /
    • pp.78-87
    • /
    • 2021
  • In this study, we firstly compute the energies and the angles of Frenet vector fields in Lorentz 5-space ��5. Then we obtain the bienergies and biangels of Frenet vector fields in ��5 by using the values of energies and angles. Finally, we present the relations among energies, angles, bienergies, and biangles with graphics.

Computational Prediction of Solvation Free Energies of Amino Acids with Genetic Algorithm

  • Park, Jung-Hum;Lee, Jin-Won;Park, Hwang-Seo
    • Bulletin of the Korean Chemical Society
    • /
    • 제31권5호
    • /
    • pp.1247-1251
    • /
    • 2010
  • We propose an improved solvent contact model to estimate the solvation free energies of amino acids from individual atomic contributions. The modification of the solvation model involves the optimization of three kinds of parameters in the solvation free energy function: atomic fragmental volume, maximum atomic occupancy, and atomic solvation parameters. All of these atomic parameters for 17 atom types are developed by the operation of a standard genetic algorithm in such a way to minimize the difference between experimental and calculated solvation free energies. The present solvation model is able to predict the experimental solvation free energies of amino acids with the squared correlation coefficients of 0.94 and 0.93 for the parameterization with Gaussian and screened Coulomb potential as the envelope functions, respectively. This result indicates that the improved solvent contact model with the newly developed atomic parameters would be a useful tool for the estimation of the molecular solvation free energy of a protein in aqueous solution.

탄화수소류의 결합해리에너지와 라디칼 반응의 안정화에너지에 대한 섭동분자궤도론적 연구 (Pertubation MO Treatments for Stabilization Energy of Radical Reaction and Bond Dissociation Energy of Some Hydrocarbons)

  • 이갑룡;서만철;김호순
    • 대한화학회지
    • /
    • 제34권2호
    • /
    • pp.136-142
    • /
    • 1990
  • 탄화수소류에 대해서 PMO (Pertubation Molecular Orbital) 방법으로 NBMO (Nonbonding Molecular Orbital) 계수를 구하여 안정화에너지 ${\delta}E$를 계산하였다. 그 결과 ${\delta}E$값은 라디칼 반응의 활성화에너지, 결합해리에너지 및 방사선 조사시 생성되는 생성물의 생성확률(G 값)과 좋은 상관성을 보였다.

  • PDF

대체에너지를 이용한 발전기술의 경제성평가 (Economic Evaluation of Generating Systems Using Renewable Energies)

  • 조인승;이창호;진병문
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1999년도 추계학술대회 논문집 학회본부 A
    • /
    • pp.172-174
    • /
    • 1999
  • In Korea, the consumption of renewable energy among primary energies has marked only 1.03%, composed of mostly hydro power facilities, as of 1998. This situation has been basically due to the market limit and high generation cost of renewable energies. Furthermore, the policies and strategies for promoting the renewable energy have been insufficient in comparison with that of the developed countries. This paper mainly focuses on the economic feasibility and sensitivity analysis for renewable energies.

  • PDF

실리카에 담지된 바나듐 촉매의 산성도에 대한 CNDO/2 분자궤도론적 계산 (CNDO/2 MO Calculations for Catalytic Acidity of V-silicalite)

  • 김명철
    • 공업화학
    • /
    • 제5권2호
    • /
    • pp.357-360
    • /
    • 1994
  • V-silicalite의 활성점을 표현하는 몇 가지 분자 cluster모델에 대하여 CNDO/2 계산을 수행하고 Wiberg결합차수와 LUMO에너지 및 전체에너지를 얻었다. 제안된 각 모델 분자들의 B산성도는 O-H결합의 결합차수를 통해 조사하였다. 또한 계산으로부터 구한 LUMO에너지는 각 활성점 모델의 L산성도를 나타내었다. 각 cluster모델의 구조적 안정성은 전체에너지를 통해 설명하였다.

  • PDF

Numerical procedure for the vibration analysis of arbitrarily constrained stiffened panels with openings

  • Cho, Dae Seung;Vladimir, Nikola;Choi, Tae Muk
    • International Journal of Naval Architecture and Ocean Engineering
    • /
    • 제6권4호
    • /
    • pp.763-774
    • /
    • 2014
  • A simple and efficient vibration analysis procedure for stiffened panels with openings and arbitrary boundary conditions based on the assumed mode method is presented. Natural frequencies and modes are determined by solving an eigenvalue problem of a multi-degree-of-freedom system matrix equation derived by using Lagrange's equations of motion, where Mindlin theory is applied for plate and Timoshenko beam theory for stiffeners. The effect of stiffeners on vibration response is taken into account by adding their strain and kinetic energies to the corresponding plate energies whereas the strain and kinetic energies of openings are subtracted from the plate energies. Different stiffened panels with various opening shapes and dispositions for several combinations of boundary conditions are analyzed and the results show good agreement with those obtained by the finite element analysis. Hence, the proposed procedure is especially appropriate for use in the preliminary design stage of stiffened panels with openings.

Relationships between the Raman Excitation Photon Energies and Its Wavenumbers in Doped trans-Polyacetylene

  • Kim, Jin-Yeol;Kim, Eung-Ryul;Ihm, Dae-Woo;Tasumi, Mitsuo
    • Bulletin of the Korean Chemical Society
    • /
    • 제23권10호
    • /
    • pp.1404-1408
    • /
    • 2002
  • The resonance Raman spectra of trans-polyacetylene films doped heavily with electron donor (Na) and acceptor (HClO4) have been measured with excitation wavelengths between 488- and 1320-nm, and the relationships between the Raman excitation photon energies (2.54-0.94 eV) and its wavenumbers were discussed. We found the linear dependence of the Raman shifts with the exchanges of excitation photon energies. In particular, the Raman wavenumbers in the C=C stretching $(V_1$ band) showed a dramatic decrease with the increase in Raman excitation photon energies. In the case of acceptor doping, its change is larger than that of donor doping. The observed wavenumber (1255-1267 $cm^{-1}$) of the $V_2$ band (CC stretch) of Na-doped form is lower than that of the corresponding band (1290-1292 $cm^{-1}$) of its pristine trans-polyacetylene, whereas the contrary is the case for the HClO4 doped form (1295-1300 $cm^{-1}$). The origin of doping-induced Raman bands is discussed in terms of negative and positive polarons.

QFPR Analysis for Selectivity of between Na+ and Li+ Ions to 12-Crown-4: by a Monte Carlo Simulation Study

  • Kim, Hag-Sung
    • Bulletin of the Korean Chemical Society
    • /
    • 제31권10호
    • /
    • pp.2823-2829
    • /
    • 2010
  • We investigated the solvent effects on the relative free energies of binding of $Na^+$ and $Li^+$ ions to 12-crown-4 and ${\Delta}log\;K_s$ (the difference of stability constant of binding) by a Monte Carlo simulation of statistical perturbation theory (SPT) in several solvents. Comparing the relative free energies of binding of $Na^+$ and $Li^+$ ions to 12-crown-4, in $CH_3OH$ of this study with experimental works, there is a good agreement among the studies. We have reported the quantitative free energy polarity (of solvent) relationships (QFPR) of the relationship between the relative free energies and solvent polarity studied on the solvent effects on the relative free energies of binding of $Na^+$ and $Li^+$ ions to 12-crown-4.

Diffraction Analysis of LC Gratings based on Linearly Graded Phase Model for Surface Anchoring Energies

  • Yu, Chang-Jae;Lee, Sin-Doo
    • Journal of Information Display
    • /
    • 제8권3호
    • /
    • pp.22-28
    • /
    • 2007
  • We reported the diffraction analysis of the liquid crystal (LC) binary gratings and the surface anchoring energies for planar and homeotropic alignments. The planar and homeotropic anchoring energies were directly derived based on the linearly distorted director distribution near domain boundaries, in which the distorted lengths correspond to the extrapolation lengths into both planar and homeotropic regions. From the diffraction analysis for the LC binary gratings with various grating periods based on the linearly graded phase model, both distorted lengths into planar and homeotropic regions were simultaneously obtained. In this work, the planar and homeotropic anchoring energies were found to be about $1.4\;{\times}\;10^{-4}\;J/m^2$ and $0.9\;{\times}\;10^{-5}\;J/m^2$, respectively.

Exciton Binding Energies in GaAs-Al\ulcornerGa\ulcornerAs and In\ulcornerGa\ulcornerAs-Inp Quantum Well Structures

  • Lee, Jong-Chul
    • Journal of Electrical Engineering and information Science
    • /
    • 제2권6호
    • /
    • pp.106-110
    • /
    • 1997
  • The binding energies of the ground state of both the heavy-hole and light-hole excitons in a GaAs(In\ulcornerGa\ulcornerAs) quantum well sandwiched between two semi-infinite Al\ulcornerGa\ulcornerAs(InP) layers are calculated as a function of well width in the presence of an arbitray magnetic field. A variational approach is followed using very simple trial wave function. The applied magnetic field is assumed to be parallel to the axis of growth and the binding energies are calculated for a finite value of the height of the potential barrier. The exciton binding energies for a given value of the magnetic field are found to be increased than their values in a zero magnetic field due to the compression of their wave functions within the well with the applied magnetic field.

  • PDF