Results 271 to 280 of about 15,388 (303)

Internal positivity preserved model reduction

International Journal of Control, 2009
This 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, James Lam, Zhan Shu 0001, Qing Wang 0051   +3 more
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Preserving positive realness through discretization

Proceedings of the 2000 American Control Conference. ACC (IEEE Cat. No.00CH36334), 2000
Continuous linear systems with positive real transfer functions have desirable stability and realizability properties. The conditions to guarantee that continuous positive realness is preserved under discretization by a standard sampler and zero order hold are investigated here.
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Nica’s q-Convolution is Not Positivity Preserving

Communications in Mathematical Physics, 2005
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Positivity-Preserving Scattered Data Interpolation

2005
The 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, Tim N. T. Goodman, Keith Unsworth   +2 more
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Preservations of Positive Realness under Discretizations

1993 American Control Conference, 1993
Positive Realness preservation properties of five commonly used discretization methods have been examined in this paper.
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Families of positivity preserving but not completely positive superoperators

Physics Letters A, 2005
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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The tail of a positivity-preserving semigroup

Israel Journal of Mathematics, 1974
With certain assumptions a representation theorem is proved for the elements of $$ \cap _{\sigma \in \Sigma } $$ σS, where Σ is an abelian semigroup of, endomorphisms of a real vector space, andS is a convex antisymmetric cone.
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Preservation Librarian: Position Overview

2019
50 years after Frazer Poole was named the first Preservation Librarian at the Library of Congress, Preservation Librarianship is a small but mature field in research libraries. Since Poole began his work, the core responsibilities of the position, namely to ensure enduring access to collections acquired and held by libraries, remain essentially ...
Durant, Fletcher, Smith, Bonnie
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Positivity Preserving Model Reduction

2009
We propose a model reduction method for positive systems that ensures the positivity of the reduced model. Our approach is based on constructing diagonal solutions of Lyapunov inequalities. These are linear matrix inequalities (LMIs), which are shown to be feasible.
Timo Reis, Elena Virnik
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Preserving Positive Isotropic Curvature

2010
The condition of positive curvature on totally isotropic 2-planes was first introduced by Micallef and Moore [MM88].
Ben Andrews, Christopher Hopper
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