The Property of Kippenhahn Curves of Kronecker Sum and Applications
In many physical applications, we must solve a system of linear equations such as . The Kronecker sum can get a convenient representation for linear equations . In this paper, let and be denoted reducible companion matrices. We study the property of the Kippenhahn curve and of the numerical rang being an elliptic disc by making use of matrices Kronecker sum and the Kippenhahn curve continually.
W. L. Zhao "The Property of Kippenhahn Curves of Kronecker Sum and Applications", Advanced Materials Research, Vols. 108-111, pp. 670-675, 2010