Results 1 to 10 of about 8,645,088 (296)

Index event bias—a numerical example [PDF]

Journal of Clinical Epidemiology, 2013
Studies of determinants of recurrent disease often give unexpected results. In particular, well-established risk factors may seem not to have much influence on the recurrence risk. Recently, it has been argued that such paradoxical findings may be because of the bias caused by the selection of patients based on the occurrence of an earlier episode of ...
Smits, Luc J. M., van Kuijk, Sander M. J., Leffers, Pieter, Peeters, Louis L., Prins, Martin H., Sep, Simone J. S.   +5 more
openaire   +4 more sources

Logarithmic stability in determination of a 3D viscoelastic coefficient and a numerical example

Inverse Problems, 2010
Maya de Buhan, Axel Osses
exaly   +2 more sources

Dedalus: A flexible framework for numerical simulations with spectral methods [PDF]

Physical Review Research, 2019
Numerical solutions of partial differential equations enable a broad range of scientific research. The Dedalus Project is a flexible, open-source, parallelized computational framework for solving general partial differential equations using spectral ...
K. Burns, G. Vasil, J. Oishi, D. Lecoanet, B. Brown   +4 more
semanticscholar   +1 more source

Direct numerical simulation of turbulent channel flow up to $\mathit{Re}_{{\it\tau}}\approx 5200$ [PDF]

Journal of Fluid Mechanics, 2014
A direct numerical simulation of incompressible channel flow at a friction Reynolds number ( $\mathit{Re}_{{\it\tau}}$ ) of 5186 has been performed, and the flow exhibits a number of the characteristics of high-Reynolds-number wall-bounded turbulent ...
Myoungkyu Lee, R. Moser
semanticscholar   +1 more source

Direct numerical simulation of turbulence at lower costs [PDF]

, 1995
Direct Numerical Simulation (DNS) is the most accurate, but also the most expensive, way of computing turbulent flow. To cut the costs of DNS we consider a family of second-order, explicit one-leg time-integration methods and look for the method with the
Veldman, A.E.P., Verstappen, R.W.C.P., Verstappen, R.W.C.P.,, Veldman, A.E.P.,, R.W.C.P. Verstappen, A.E.P. Veldman   +5 more
core   +1 more source

Numerical upscaling for heterogeneous materials in fractured domains [PDF]

, 2021
We consider numerical solution of elliptic problems with heterogeneous diffusion coefficients containing thin highly conductive structures. Such problems arise e.g. in fractured porous media, reinforced materials, and electric circuits.
Siyang Wang, Wang, S. Y., Hellman, Fredrik, Axel Målqvist, Wang, Siyang, Målqvist, Axel,, Wang, Siyang,, Fredrik Hellman, M\ue5lqvist, Axel, Hellman, Fredrik,   +9 more
core   +1 more source

Exact solutions and numerical study of time fractional Burgers' equations

Applied Mathematics Letters, 2020
In this paper, we investigate the exact and numerical solutions of the time fractional Burgers’ equation. By using Cole–Hopf transformation and the method of variables separation, the exact solution is presented in terms of the Mittag-Leffler functions ...
Lili Li, Dongfang Li
semanticscholar   +1 more source

Numerical Distribution Functions for Unit Root and Cointegration Tests

, 1996
This paper employs response surface regressions based on simulation experiments to calculate distribution functions for some well-known unit root and cointegration test statistics.
J. MacKinnon
semanticscholar   +1 more source

Solutions of the Nonlinear Integral Equation and Fractional Differential Equation Using the Technique of a Fixed Point with a Numerical Experiment in Extended b-Metric Space

Symmetry, 2019
The present paper aims to define three new notions: Θ e -contraction, a Hardy–Rogers-type Θ -contraction, and an interpolative Θ -contraction in the framework of extended b-metric space.
T. Abdeljawad, R. Agarwal, E. Karapınar, P. Kumari   +3 more
semanticscholar   +1 more source

A numerical evaluation of solvers for the periodic Riccati differential equation

, 2009
Efficient and accurate structure exploiting numerical methods for solving the periodic Riccati differential equation (PRDE) are addressed. Such methods are essential, for example, to design periodic feedback controllers for periodic control systems ...
Andras Varga, Varga, Andreas, Varga, Andras,, Varga, Andras, Sergei Gusev, Kagström, Bo, Anton Shiriaev, Gusev, Sergei,, Shiriaev, Anton,, Stefan Johansson, Johansson, Stefan, Shiriaev, Anton, Kågström, Bo,, Gusev, Sergei, Johansson, Stefan,   +14 more
core   +1 more source