Results 221 to 230 of about 94,977 (261)

General Langevin Equations and Functional Integration

1981
We study functional integral representations for the transition probability density of Markov processes defined by general nonlinear Langevin equations. We give a review of our work covering the definition through discretization, the relation to ordering problems in the operator formalism and the ambiguities of perturbation expansions.
F. Langouche, D. Roekaerts, E. Tirapegui
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Langevin analysis of fission excitation functions induced by protons

Chinese Physics C, 2015
The stochastic Langevin approach to fission is applied to analyze fission excitation functions measured in p+206Pb and p+209Bi systems. A presaddle friction strength of (3–5) × 1021 s−1 is extracted by comparing theoretical predictions with experimental data.
Jian Tian, Ning Wang, Wei Ye
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Taylor expansion of the inverse function with application to the Langevin function

Mathematics and Mechanics of Solids, 2012
A Taylor power series is a powerful mathematical tool, which can be used to express an inverse function especially if it is given in an implicit form. This is for example the case for the inverse Langevin function, which is an indispensable ingredient of full-network rubber models.
Itskov, Mikhail, Dargazany, Roozbeh, Hörnes, Karl   +2 more
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A Pad� approximant to the inverse Langevin function

Rheologica Acta, 1991
Application of the methodology of Pade approximants to a Taylor expansion of the inverse Langevin function led to an accurate analytical expression. The approximation, retaining a finite extendibility of the Langevin spring, enables a convenient analysis of experimental data and analytical manipulations of material models.
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Solution of the fractional Langevin equation and the Mittag–Leffler functions

Journal of Mathematical Physics, 2009
We introduce the fractional generalized Langevin equation in the absence of a deterministic field, with two deterministic conditions for a particle with unitary mass, i.e., an initial condition and an initial velocity are considered. For a particular correlation function, that characterizes the physical process, and using the methodology of the Laplace
Camargo, R. Figueiredo, Chiacchio, Ary O., Charnet, R., de Oliveira, E. Capelas   +3 more
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Langevin machine: a neural network based on stochastically justifiable sigmoidal function

Biological Cybernetics, 1991
In neural networks the activation process controls the output as a nonlinear function of the input; and, this output remains bounded between limits as decided by a logistic function known as the sigmoid (S-shaped). Presently, by applying the considerations of Maxwell-Boltzmann statistics, the Langevin function is shown as the appropriate and ...
P S, Neelakanta, R, Sudhakar, D, DeGroff
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Nonlinear Langevin equations and the time dependent density functional method

Physical Review E, 1999
To study the time dependent density functional method (TDDFM), two streaming velocity (reversible) terms are reformulated in the nonlinear Langevin equation. Mori's [Prog. Theor. Phys. 33, 423 (1965)] projection operator method shows a variety of nonlinear Langevin equations.
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Long‐Time Behaviour of Langevin Algorithms with Time‐dependent Energy Function

Mathematische Nachrichten, 1995
AbstractWe study the Langevin algorithm on C∞ n‐dimensional compact connected Riemannian manifolds and on IRn, allowing the energy function U to vary with time. We find conditions under which the distribution of the process at hand becomes indistinguishable as t → ∞ from the “instantaneous” equilibrium distribution.
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Non-linear magnetic field analysis by FEM using Langevin function

IEEE Transactions on Magnetics, 2000
This work presents an improved method to take into account the magnetic nonlinearity in time-stepped two dimensional finite element calculations. A differential magnetic reluctivity tensor is employed. Also, in order to model the nonlinearity, a Langevin function is used. Numerical convergence is faster than classical procedures.
L.A. Righi, P.I. Koltermann, N. Sadowski, J.P.A. Bastos, R. Carlson, A. Kost, L. Janicke, D. Lederer   +7 more
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Correlation functions and masterequations of generalized (non-Markovian) Langevin equations

Zeitschrift f�r Physik B Condensed Matter and Quanta, 1978
For the statistical behavior of macrovariables described in terms of Langevin equations with a in general colored random force we deduce useful formulas which simplify the calculation of correlation functions. Utilizing these results and the stochastic properties of the random force we derive an exact time-convolutionless masterequation for the ...
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