Results 231 to 240 of about 94,977 (261)

A Generalized Approach to Improve Approximation of Inverse Langevin Function

Volume 9: Mechanics of Solids, Structures, and Fluids, 2018
The inverse Langevin function has a crucial role in different research fields, such as polymer physics, para- or superpara-magnetism materials, molecular dynamics simulations, turbulence modeling, and solar energy conversion. The inverse Langevin function cannot be explicitly derived and thus, its inverse function is usually approximated using rational
Vahid Morovati, Hamid Mohammadi, Roozbeh Dargazany   +2 more
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A simple and accurate approximation of the inverse Langevin function

Rheologica Acta, 2015
The inverse Langevin function cannot be represented in an explicit form and requires an approximation by a series, a non-rational or a rational function as for example by a Pade approximation. In the current paper, an analytical method based on the Pade technique and the multiple point interpolation is presented for the inverse Langevin function. Thus,
Ehsan Darabi, Mikhail Itskov
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Generalized Langevin equation with fractional derivative and long-time correlation function

Physical Review E, 2006
We investigate the motion of a particle governed by a generalized Langevin equation with fractional derivative, nonlocal dissipative force, and long-time correlation function. We derive general expressions for the variances with a linear external force.
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Generalized Langevin equation with multiplicative noise: Temporal behavior of the autocorrelation functions

Physical Review E, 2011
The temporal behavior of the mean-square displacement and the velocity autocorrelation function of a particle subjected to a periodic force in a harmonic potential well is investigated for viscoelastic media using the generalized Langevin equation. The interaction with fluctuations of environmental parameters is modeled by a multiplicative white noise,
R, Mankin, K, Laas, A, Sauga
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Functional Langevin models for the mesoscopic dynamics of surfactant aggregation in solution

Physical Review E, 1996
We discuss a time-dependent potential model for the simulation of surfactant aggregation In solution. The numerical model is derived from a generalization of time-dependent Ginzburg-Landau theory or conserved order parameters. An element in our coarse-grained approach is that we retain important aspects of molecular detail by inclusion of single-chain ...
van Vlimmeren, B.A.C., Postma, M., Huetz, P., Brisson, A., Fraaije, J.G E M   +4 more
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Exact exponential function solution of the generalized Langevin equation for autocorrelation functions of many-body systems

Physical Review E, 2012
We show that an exact solution of the generalized Langevin equation (GLE) for the autocorrelations of a many-body classical system can be given in an exponential functionality (EF) form. As a consequence, the power spectrum of the correlation has a Lorentzian functionality, i.e., is represented by an infinite sum of Lorentzian functions corresponding ...
Fabrizio Barocchi, Ubaldo Bafile, Marco Sampoli   +2 more
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New facts concerning the approximation of the inverse Langevin function

Journal of Non-Newtonian Fluid Mechanics, 2017
Abstract The inverse Langevin function is an integral component for statistically-based network models which describe rubber-like materials. This function is very important from theoretical and practical points of view in variety of scientific fields like rheology, theory of magnetism and polymer science.
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Modified langevin functions for new birefringence effects in molecular liquids

Journal of Molecular Liquids, 1988
Abstract New types of Langevin function are developed for the analytical description of birefringence and anisotropy effects discovered recently by supercomputer simulation of molecular liquids. These include Langevin and Kielich functions for birefringence induced by a circularly polarised laser field, and for electric field induced anisotropy in ...
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A Langevin approach to fermion and quantum spin correlation functions

Journal of Physics A: Mathematical and General, 1983
By using spin-coherent states, the author shows that correlation functions for fermions or quantum spins follow from solutions to Langevin equations associated with a functional integral representation of the partition function. His method is applicable to any number of dimensions, may also be combined with boson variables, and is suitable for computer
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Complex Langevin and other approaches to the sign problem in quantum many-body physics

Physics Reports, 2021
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