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arXiv · 2103.02541

Representation of rational positive real functions of several variables by means of positive long resolvent

M. F. Bessmertnyi
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Abstract

A rational homogeneous (of degree one) positive real matrix-valued function is presented as the Schur complement of a block of the linear pencil with positive semidefinite matrix coefficients. The partial derivative numerators of a rational positive real function are the sums of squares of polynomials.

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M. F. Bessmertnyi. 2021-03-03. Representation of rational positive real functions of several variables by means of positive long resolvent. https://arxiv.org/abs/2103.02541

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