Sökning: "Herglotz functions"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden Herglotz functions.

  1. 1. On Herglotz-Nevanlinna functions in several variables

    Författare :Mitja Nedic; Annemarie Luger; B. L. G. Jonsson; Ragnar Sigurðsson; Pamela Gorkin; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Herglotz-Nevanlinna functions; several complex variables; integral representations; Nevanlinna measures; Herglotz-Nevanlinnafunktioner; flera komplexa variabler; integralframställningar; Nevanlinnamått; Mathematics; matematik;

    Sammanfattning : In this thesis, we investigate different aspects of the class of Herglotz-Nevanlinna functions in several variables. These are holomorphic functions on the poly-upper half-plane having non-negative imaginary part. Our results are presented in the four research articles A1 - A4, which are included in this thesis. LÄS MER

  3. 2. Integral representations of Herglotz-Nevanlinna functions

    Författare :Mitja Nedic; Annemarie Luger; Alexandru Aleman; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; integral representations; Herglotz-Nevanlinna functions; several complex variables; Mathematics; matematik;

    Sammanfattning : In this thesis, we study integral representations of Herglotz-Nevanlinna functions, that is to say holomorphic functions defined on a product of several copies of the complex upper half-plane having non-negative imaginary part. The manuscript is divided into three parts, beginning with a general introduction followed by two papers. LÄS MER

  4. 3. Optimization and Physical Bounds for Passive and Non-passive Systems

    Författare :Yevhen Ivanenko; Sven Nordebo; Börje Nilsson; Mats Gustafsson; Mariana Dalarsson; Aaron Welters; Linnéuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Convex optimization; physical bounds; Herglotz functions; quasi-Herglotz functions; passive systems; non-passive systems; approximation; absorption in lossy media; Waves; Signals and Systems; Vågor; signaler och system;

    Sammanfattning : Physical bounds in electromagnetic field theory have been of interest for more than a decade. Considering electromagnetic structures from the system theory perspective, as systems satisfying linearity, time-invariance, causality and passivity, it is possible to characterize their transfer functions via Herglotz functions. LÄS MER

  5. 4. Dispersion Relations in Scattering and Antenna Problems

    Författare :Christian Sohl; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; acoustic and electromagnetic waves; sum rules; scattering and absorption; causality; Herglotz functions;

    Sammanfattning : This dissertation deals with physical bounds on scattering and absorption of acoustic and electromagnetic waves. A general dispersion relation or sum rule for the extinction cross section of such waves is derived from the holomorphic properties of the scattering amplitude in the forward direction. LÄS MER

  7. 5. Estimation of electromagnetic material properties with application to high-voltage power cables

    Författare :Yevhen Ivanenko; Sven Nordebo; Martin Norgren; Linnéuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Material losses; power cables; cylindrical multipole expansion; Herglotz functions; convex optimization; sum rules; Waves and Signals; Vågor och signaler;

    Sammanfattning : Efficient design of high-voltage power cables is important to achieve an economical delivery of electric power from wind farms and power plants over the very long distances as well as the overseas electric power. The main focus of this thesis is the investigation of electromagnetic losses in components of high-voltage power cables. LÄS MER