Results 51 to 60 of about 7,957,612 (305)
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 +5 more
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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 +3 more
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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
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A high order positivity-preserving conservative WENO remapping method on 3D tetrahedral meshes
Computer Methods in Applied Mechanics and Engineering, 2022 We propose a high order positivity-preserving conservative remapping method on three-dimensional (3D) tetrahedral meshes, based on the weighted essentially non-oscillatory (WENO) reconstruction method.
Nuo Lei, Juan Cheng, Chi-Wang Shu
semanticscholar +1 more source
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
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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
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Positivity-preserving strategies and their comparision based on staggered CPR methods
Kongqi donglixue xuebaoHigh-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 +3 more
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A high order positivity-preserving conservative WENO remapping method based on a moving mesh solver
Journal of Computational Physics, 2022 In this paper, a high order accurate positivity-preserving conservative remapping algorithm is developed. Quadrilateral meshes in two dimensions are used as examples. This remapping method is based on the numerical solution of the trivial equation ∂u∂t =
Xiaolu Gu +3 more
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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
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Efficient Positivity-Preserving NSFD Scheme: Application to Advection-Diffusion-Reaction Equation [PDF]
Journal of Applied and Computational MechanicsSolving problems across a wide range of scientific and engineering domains, encompassing physical, mechanical and biological systems as well as financial markets, necessitates addressing parabolic equations of the advection-diffusion-reaction (ADR ...
Reza Shokri Jahandizi +3 more
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