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Positivity Preservation Properties of the Rantzer Multipliers
IEEE Transactions on Automatic Control, 2011The Rantzer multipliers are known to preserve the positivity of certain aberrations of memoryless monotone positive nonlinearities. We show that if the nonlinearity input is constrained to be positive valued for all time instants, these multipliers are positivity preserving for a larger class of nonlinearities.
Vishwesh V. Kulkarni 0001 +2 more
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On the Positivity Preserving Property of Hinged Plates
SIAM Journal on Mathematical Analysis, 2009In this work we show that the Kirchhoff–Love model for a hinged plate $\Delta^2 v = f \text{ in }E,\; v = \Delta v - (1 - \sigma) \kappa v_n = 0 \text{ on }\partial E$ admits, for $f \in L^2(E)$ and $-1 < \sigma < 1$, a unique weak solution in $W^{2,2}(E) \cap W^{1,2}_0(E)$ which satisfies the positivity preserving property when $E \subset \mathbb{R}^2$
Enea Parini, Athanasios Stylianou
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Positivity-Preserving Schemes in Multidimensions
SIAM Journal on Scientific Computing, 2000The performance of the MUSCL-Hancock upwind scheme is examined on problems of two-dimensional advection. It is found that when the advection direction is skewed relative to the mesh, most discrete total variation diminishing (TVD) limiters give rise to large spurious oscillations near discontinuities.
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Internal positivity preserved model reduction
International Journal of Control, 2009This article studies model reduction of continuous-time stable positive linear systems under the Hankel norm, H ∞ norm and H 2 norm performance. The reduced-order systems preserve the stability as well as the positivity of the original systems. This is achieved by developing new necessary and sufficient conditions of the model reduction performances in
Jun-e Feng +3 more
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Positivity Preserving Semigroups and Positivity Preserving Coercive Forms
2018We recall the idea of Ma and Rockner (Canad. J. Math., 47:817–840, 1995, [13]) and report some further progress along the line of the research initiated by Ma and Rockner (Canad. J. Math., 47:817–840, 1995, [13]). The further progress includes the technique of \(h\hat{h}\)-transformations for positivity preserving semigroups, and includes our recent ...
Xian Chen, Zhi-Ming Ma, Xue Peng
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Positivity Preserving Exponential Integrators for Differential Riccati Equations
Journal of Scientific Computing, 2023zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Hao Chen 0015, Alfio Borzì
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Nica’s q-Convolution is Not Positivity Preserving
Communications in Mathematical Physics, 2005zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Positivity Preserving Balanced Truncation for Descriptor Systems
SIAM Journal on Control and Optimization, 2009We propose a model reduction method for positive systems that ensures the positivity of the reduced-order model. In the standard as well as in the descriptor case, for continuous-time and discrete-time systems, our approach is based on constructing diagonal solutions of Lyapunov inequalities. These are linear matrix inequalities (LMIs), which are shown
Timo Reis, Elena Virnik
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Positivity-Preserving Scattered Data Interpolation
2005The construction of a C1 interpolant to scattered data is considered in which the interpolant is positive everywhere if the original data are positive. This study is motivated by earlier work in which sufficient conditions are derived on Bezier points in order to ensure that surfaces comprising cubic Bezier triangular patches are always positive.
Abd. Rahni Mt. Piah +2 more
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