Results 71 to 80 of about 570,809 (200)

Reconstruction and deceleration-acceleration transitions in modified gravity [PDF]

, 2010
We discuss the cosmological reconstruction in modified Gauss-Bonnet and F(R) gravities. Two alternative representations of the action (with and without auxiliary scalar) are considered.
Nojiri, Shin'ichi, Odintsov, Sergei D., Toporensky, Alexey, Tretyakov, Petr   +3 more
core   +2 more sources

New Approximate Analytical Solutions of the Falkner‐Skan Equation [PDF]

Journal of Applied Mathematics, 2012
We propose an iterative method for solving the Falkner‐Skan equation. The method provides approximate analytical solutions which consist of coefficients of the previous iterate solution. By some examples, we show that the presented method with a small number of iterations is competitive with the existing method such as Adomian decomposition method ...
openaire   +4 more sources

Innovative Application of the Ritz Method to Oil-Gas Seepage Problems: A Novel Variational Approach for Solving Underground Flow Equations

Energies
State-of-the-art commercial simulators (e.g., Eclipse, CMG) predominantly employ finite difference schemes, which face persistent challenges in modeling strongly nonlinear seepage dynamics. This study explores the application of the Ritz method, grounded
Xiongzhi Liu, Hao Yang, Lifei Dong, Ming Lei, Jie Han, Hao Kang   +5 more
doaj   +1 more source

Developing Clean Technology through Approximate Solutions of Mathematical Models [PDF]

, 2012
In this paper, the role of mathematical modeling in the development of clean technology has been considered. One method each for obtaining approximate solutions of mathematical models by ordinary differential equations and partial differential ...
Anake, T. A.
core   +1 more source

Optimal homotopy asymptotic method for flow and heat transfer of a viscoelastic fluid in an axisymmetric channel with a porous wall. [PDF]

PLoS ONE, 2013
In this article, an approximate analytical solution of flow and heat transfer for a viscoelastic fluid in an axisymmetric channel with porous wall is presented.
Fazle Mabood, Waqar A Khan, Ahmad Izani Md Ismail   +2 more
doaj   +1 more source

A skeleton approximate solution of the Einstein field equations for multiple black-hole systems

, 2004
An approximate analytical and non-linear solution of the Einstein field equations is derived for a system of multiple non-rotating black holes. The associated space-time has the same asymptotic structure as the Brill-Lindquist initial data solution for ...
A. Komar, A. Lichnerowicz, D.D. Holm, D.R. Brill, E. Gourgoulhon, G. Schäfer, G.B. Cook, G.B. Cook, Gerhard Schäfer, Guillaume Faye, H.P. Pfeiffer, H.P. Pfeiffer, J.M. Bowen, L. Blanchet, L. Blanchet, L. Blanchet, L. Blanchet, L. Blanchet, L.E. Kidder, M. Shibata, P. Grandclément, P. Jaranowski, P. Jaranowski, P. Jaranowski, P. Jaranowski, P. Jaranowski, P. Jaranowski, Piotr Jaranowski, R.J. Gleiser, S. Brandt, S.M. Kopejkin, T. Damour, T. Damour, T. Damour, T. Damour, T. Damour, T. Damour, T. Ohta, T. Regge, T.W. Baumgarte, V.C. de Andrade, Y. Itoh   +41 more
core   +1 more source

Approximate Analytical Solutions for Strongly Coupled Systems of Singularly Perturbed Convection–Diffusion Problems

Mathematics
This work presents a reliable algorithm to obtain approximate analytical solutions for a strongly coupled system of singularly perturbed convection–diffusion problems, which exhibit a boundary layer at one end. The proposed method involves constructing a
Essam R. El-Zahar, Ghaliah F. Al-Boqami, Haifa S. Al-Juaydi   +2 more
doaj   +1 more source

Comparative analysis of the approximate analytical and finite element solutions for misaligned tube

Vestnik Samarskogo Gosudarstvennogo Tehničeskogo Universiteta. Seriâ: Fiziko-Matematičeskie Nauki, 2014
The boundary value problem of steady-state creep for thick-walled misaligned tube under internal pressure was considered. The approximate analytical solution of this problem by method of small parameter including the second approach is under construction.
Vladimir P Radchenko, Anna D Moskalik, Igor' E Adeyanov   +2 more
doaj   +1 more source

Analytical Approximant to a Quadratically Damped Forced Cubic-Quintic Duffing Oscillator

The Scientific World Journal, 2022
The cubic-quintic Duffing oscillator of a system with strong quadratic damping and forcing is considered. We give elementary approximate analytical solution to this oscillator in terms of exponential and trigonometric functions. We compare the analytical
Alvaro H. S. Salas
doaj   +1 more source

Approximate analytical solution of the Graetz problem

Journal of Physics: Conference Series, 2021
Abstract The study on velocity and temperature distribution in fluid flows is important both for the theory and practical applications. The design of efficient heat-exchange equipment, the development of heat and thermomechanical modes of product treatment, the determination of heat losses in the pipeline systems include the need to ...
openaire   +1 more source