Some Matrix Inequalities in Multiport Network Connections

  • Tsuyoshi Ando
  • Fumio Kubo
Part of the Operator Theory: Advances and Applications book series (OT, volume 40)


Connections of resistive multiport electrical networks give rise to several questions concerning comparisons among certain functions of impedance matrices of branch networks. In the present paper, some matrix inequalities, related to symmetric function means of an n-tuple of positive definite matrices, are proved to answer a part of the conjectures of Anderson, Morley and Trapp.


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Copyright information

© Birkhäuser Verlag Basel 1989

Authors and Affiliations

  • Tsuyoshi Ando
    • 1
  • Fumio Kubo
    • 2
  1. 1.Division of Applied Mathematics, Research Institute of Applied ElectricityHokkaido UniversitySapporo 060Japan
  2. 2.Department of Mathematics Faculty of ScienceToyama UniversityToyama 930Japan

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