Results 251 to 260 of about 109,202 (281)

Higher Order Perturbation Method in Reactor Calculations

Nuclear Science and Engineering, 1973
AbstractA higher order perturbation formula for calculating changes in the reactivity up to a desired order in concise form is given; the formula uses the iterative technique well known in quantum mechanics and in the neutron life-cycle method. This procedure is possible only when the adjoint flux in the unperturbed system is used as the weighting ...
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Stochastic Higher-Order Generalized Perturbation Theory for Neutron Diffusion and Transport Calculations

Volume 6: Beyond Design Basis Events; Student Paper Competition, 2013
The role of scientific computing has been heavily promoted in many fields to improve understanding the physics of complex engineering systems in recent years while conduct the experiments can be time-consuming, inflexible, expensive and difficult to repeat, e.g. nuclear reactor systems.
Congjian Wang, Hany S. Abdel-Khalik
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Use of continued fractions for the calculation of higher-order terms in a perturbation system

Chemical Physics Letters, 1981
Abstract Higher-order terms of eigenvalues in a perturbation system with discrete energy levels described by the Schrodinger equation are calculated using continued fractions. This method is used for calculating energy eigenvalues for a rigid rotator which has a dipole and interacts with an applied electric field.
Akio Morita, Hiroshi Watanabe
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Fast convergence and higher-order mode calculation of optical waveguides: perturbation method with finite difference algorithm

Optics & Laser Technology, 2005
We present an efficient algorithm for determining mode eigenvalues as well as field distributions of optical waveguides with two-dimensional transverse refractive index profile. The algorithm is devised with the analytical perturbation correction method combined with the finite difference approximation of Helmoltz's equation.
Partha Roy Chaudhuri, A.K. Ghatak, B.P. Pal, C. Lu   +3 more
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A perturbation method suitable for higher order calculations

Journal of Molecular Spectroscopy, 1965
Abstract A form of perturbation theory is described which is particularly useful for the calculation of the higher order corrections. In technique of application, the method is intermediate to the usual Rayleigh-Schrodinger method and the contact transformation technique of Van Vleck, but it appears to be more appropriate than either for a number of ...
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Calculation of the higher-order perturbations in the theory of gamma transport

Soviet Physics Journal, 1968
The higher-order perturbations in the application of perturbation theory to the γ-transport equation are discussed. An analytic expression is obtained for the perturbation flux of arbitrary order arising from a variation in the electron density of the medium, regardless of its geometry.
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Calculations combining the multiconfiguration Hartree-Fock method and many-body perturbation theory. III. Higher-order effects involving the correlation of the core

Journal of Physics B: Atomic, Molecular and Optical Physics, 1988
The multiconfiguration Hartree-Fock theory and many-body perturbation theory are combined in a calculation of the third-order contribution to the inner-shell correlation energy of the neutral beryllium atom. For this purpose, the contributions to the energy due to pair excitations from a MCHF reference state are expressed in terms of two-electron ...
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Higher Order Perturbative QCD Calculation of Jet Cross-Sections in e+ e- Annihilation

1981
We present in detail the analytic calculation of the Sterman-Weinberg type 3-jet cross section to order αs2 The fit to recent PLUTO data gives in the\({MS}\) scheme αs which corresponds to Λ=0.24 GeV in the 1-loop approximation.
Fabricius, K., Schmitt, I., Kramer, G., Schierholz, G.   +3 more
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Higher-order many-body perturbation-theory calculations of energy levels in cesium

Physical Review A, 1988
, Blundell, , Johnson, , Sapirstein
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Quantum Chemistry Calculations for Metabolomics

Chemical Reviews, 2021
Ricardo M Borges, Sean M Colby
exaly