Results 31 to 40 of about 15,388 (303)

Shape-Preserving Properties of a Relaxed Four-Point Interpolating Subdivision Scheme

Mathematics, 2020
In this paper, we analyze shape-preserving behavior of a relaxed four-point binary interpolating subdivision scheme. These shape-preserving properties include positivity-preserving, monotonicity-preserving and convexity-preserving.
Pakeeza Ashraf, Abdul Ghaffar, Dumitru Baleanu, Irem Sehar, Kottakkaran Sooppy Nisar, Faheem Khan   +5 more
doaj   +1 more source

Positivity of flux vector splitting schemes [PDF]

, 1999
Over the last ten years, robustness of schemes has raised an increasing interest among the CFD community. One mathematical aspect of scheme robustness is the positivity preserving property.
Moschetta, Jean-Marc, Villedieu, Philippe, Gressier, Jérémie   +2 more
core   +1 more source

Shape-Preservation of the Four-Point Ternary Interpolating Non-stationary Subdivision Scheme

Frontiers in Physics, 2020
In this paper, we present the shape-preserving properties of the four-point ternary non-stationary interpolating subdivision scheme (the four-point scheme). This scheme involves a tension parameter.
Pakeeza Ashraf, Mehak Sabir, Abdul Ghaffar, Kottakkaran Sooppy Nisar, Ilyas Khan   +4 more
doaj   +1 more source

On the Entropy Projection and the Robustness of High Order Entropy Stable Discontinuous Galerkin Schemes for Under-Resolved Flows

Frontiers in Physics, 2022
High order entropy stable schemes provide improved robustness for computational simulations of fluid flows. However, additional stabilization and positivity preserving limiting can still be required for variable-density flows with under-resolved features.
Jesse Chan, Hendrik Ranocha, Andrés M. Rueda-Ramírez, Gregor Gassner, Gregor Gassner, Tim Warburton   +5 more
doaj   +1 more source

Necessary conditions for reaction-diffusion system with delay preserving positivity

Electronic Journal of Qualitative Theory of Differential Equations, 2016
We consider the reaction--diffusion system with delay \begin{equation*} \left\{\begin{aligned} &\frac{\partial u}{\partial t}=A(t,x)\Delta u-\sum_{i=1}^{k}\gamma_{i}(t,x)\partial_{x_{i}}u +f(t,u_{t}) , &x\in \Omega; \\ &B(u)|_{\partial \Omega}=0.\\ \
Lirui Feng, Xue Zhang, Jianhong Wu, Messoud Efendiev   +3 more
doaj   +1 more source

Preservation of positivity by dynamical coarse graining [PDF]

Physical Review A, 2008
18 pages, 7 figures, reviewers suggestions included and tightened presentation; accepted for publication in ...
Schaller, Gernot, Brandes, Tobias
openaire   +2 more sources

Positivity Preserving Multiapproximation

American Journal of Scientific and Industrial Research, 2012
We show that the degree of copositive multipolynomial approximation to a function which changes signs finitely many times in , can be estimated by ...
Eman Bhaya, Mayada Ali
openaire   +1 more source

Positivity and Monotonicity Preserving Biquartic Rational Interpolation Spline Surface

Journal of Applied Mathematics, 2014
A biquartic rational interpolation spline surface over rectangular domain is constructed in this paper, which includes the classical bicubic Coons surface as a special case.
Xinru Liu, Yuanpeng Zhu, Shengjun Liu
doaj   +1 more source

Positivity-preserving strategies and their comparision based on staggered CPR methods

Kongqi donglixue xuebao
High-order accurate algorithms often encounter numerical instabilities, such as negative density or pressure, when simulating flow fields with strong discontinuities, extremely low density, or low pressure.
Weizhe Wang, Zhen-Guo Yan, Huajun Zhu, Xinlong Feng   +3 more
doaj   +1 more source

On the Completely Positive and Positive Semidefinite-Preserving Cones—Part III [PDF]

ISRN Algebra, 2012
This paper studies the extremals and other faces of the completely positive and positive semidefinite-preserving linear transformations.
Andrew J. Klimas, Richard D. Hill
openaire   +2 more sources