نتایج جستجو برای: numerical solution ns

تعداد نتایج: 775190  

Journal: :iranian journal of science and technology (sciences) 2013
r, mokhtari

on the basis of a reproducing kernel space, an iterative algorithm for solving the one-dimensional linear and nonlinear schrödinger equations is presented. the analytical solution is shown in a series form in the reproducing kernel space and the approximate solution is constructed by truncating the series. the convergence of the approximate solution to the analytical solution is also proved. th...

Journal: :sahand communications in mathematical analysis 2015
parviz darania jafar ahmadi shali

in this paper, we studied the numerical solution of nonlinear weakly singular volterra-fredholm integral equations by using the product integration method. also, we shall study the convergence behavior of a fully discrete version of a product integration method for numerical solution of the nonlinear volterra-fredholm integral equations. the reliability and efficiency of the proposed scheme are...

Journal: :alexandria engineering journal 2021

In this study, a novel stochastic computational frameworks based on fractional Meyer wavelet artificial neural network (FMW-ANN) is designed for nonlinear-singular Lane-Emden (NS-FLE) differential equation. The modeling strength of FMW-ANN used to transformed the NS-FLE system difference equations and approximate theory implemented in mean squared error sense develop merit function equations. M...

Journal: :Astronomy and Computing 2023

Weak gravitational lensing is one of the few direct methods to map dark-matter distribution on large scales in Universe, and estimate cosmological parameters. We study a Bayesian inference problem where data covariance C, estimated from number ns numerical simulations, singular. In context large-scale structure observations, creation such N-body simulations often prohibitively expensive. Infere...

2008
O. COSTIN S. TANVEER

We summarize a recently developed integral equation approach to tackling the long-time existence problem for smooth solution v(x, t) to the 3-D Navier-Stokes equation in the context of a periodic box problem with smooth time-independent forcing and initial condition v0. Using an inverse Laplace transform of v̂(k, t) − v̂0 in 1/t, we arrive at an integral equation for Û(k, p), where p is inverse-L...

Journal: :Philosophical transactions. Series A, Mathematical, physical, and engineering sciences 2008
Ovidiu Costin Guo Luo Saleh Tanveer

We describe how the Borel summability of a divergent asymptotic expansion can be expanded and applied to nonlinear partial differential equations (PDEs). While Borel summation does not apply for non-analytic initial data, the present approach generates an integral equation (IE) applicable to much more general data. We apply these concepts to the three-dimensional Navier-Stokes (NS) system and s...

Journal: :J. Comput. Physics 2013
Li-Jun Xuan Kun Xu

Up to an arbitrary order of the Chapman–Enskog expansion of the kinetic Bhatnagar– Gross–Krook (BGK) equation, a corresponding analytic solution can be obtained. Based on such a compact exact solution, a new gas-kinetic scheme is constructed for the compressible Navier–Stokes equations. Instead of using a discontinuous initial condition in the gas-kinetic BGK–NS method Xu [K. Xu, A gas-kinetic ...

1997
MARI PAZ CALVO ARIEH ISERLES ANTONELLA ZANNA

In this paper we are concerned with the problem of solving numerically isospectral ows. These ows are characterized by the diierential equation L 0 = B(L);L]; L(0) = L 0 ; where L 0 is a d d symmetric matrix, B(L) is a skew-symmetric matrix function of L and B;L] is the Lie bracket operator. We show that standard Runge{Kutta schemes fail in recovering the main qualitative feature of these ows, ...

1996
Jeng Yen Linda R. Petzold

One of the outstanding problems in the numerical simulation of mechanical systems is the development of eecient methods for dealing with highly oscilla-tory systems. These types of systems arise for example in vehicle simulation in modeling the suspension system or tires, in models for contact and impact, in exible body simulation from vibrations in the structural model, and in molecular dynami...

Journal: :فیزیک زمین و فضا 0
سرمد قادر دانشیار، گروه فیزیک فضا، مؤسسه ژئوفیزیک دانشگاه تهران، ایران علیرضا محب الحجه دانشیار، گروه فیزیک فضا، مؤسسه ژئوفیزیک دانشگاه تهران، ایران مرضیه شریفی دوست دانش آموخته کارشناسی ارشد هواشناسی، گروه فیزیک فضا، مؤسسه ژئوفیزیک دانشگاه تهران، ایران

to control the nonlinear numerical instability, throughout the time evolution of the eulerian form of the nonlinear rotating shallow water equations, it is necessary to add numerical diffusion to the solution. it is clear that, this extra numerical diffusion degrades the accuracy of the numerical solution and should be kept as small as possible. in a conventional approach a hyper-diffusion is u...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید