Minimal Positive Realizations of Third-Order Systems with Complex Poles.

In this paper, the conditions are discussed for the third-order systems with the complex poles to have third-order positive realizations. These systems are divided into two classes by the distribution of the complex poles. For one class, a sufficient condition is presented, and for the other one, a necessary and sufficient condition is presented. Finally some examples are given to show the contribution and limitation of these results. [ABSTRACT FROM AUTHOR]