Small gain versus positive real modeling of real parameter uncertainty

Robust stabilization with positive real uncertainty: Beyond the small gain theorem *

Abstract: In many applications of feedback control, phase information is available concerning the plant uncertainty. For example, lightly damped flexible structures with colocated rate sensors and force actuators give rise to positive real transfer functions. Closed-loop stability is thus guaranteed by means of negative feedback with strictly positive real compensators. In this paper, the prope...

Robustness under Real Parameter Uncertainty

Parameter-dependent Lyapunov Functions for Real Parametric Uncertainty

A new test of robust stability/performance is proposed for linear systems with uncertain real-valued parameters. This test is an extension of the notion of quadratic stability where the xed quadratic Lyapunov function is replaced by a Lyapunov function with aane dependence on the uncertain parameters. Admittedly with some conservatism , the construction of such parameter-dependent Lyapunov func...

The octomorphic criterion for real parameter uncertainty: Real-/l bounds without circles and D,N-scales*

In this paper we introduce new bounds for robust stability analysis with real parameter uncertainty. The approach is based on an absolute stability criterion that excludes the Nyquist plot from a paraboloidal region containing the point -1 +j0. Transformation of this criterion to the case of norm-bounded uncertainty leads to a stability criterion in terms of the octomorphic, or figure-eight sha...

Modeling of Real Estate Income Tax: System Dynamics Approach

This study aims to design a model to realize real estate income tax in Tabriz city with due attention to the tax collection process. According to the related literature, the variables of "tax payment," "real estate," "tax evasion," "investment incentive," "rent and real estate speculation," and "advertisement in tax collection" are considered as key variables, affecting the conceptual model of ...