Search for dissertations about: "mode-matching"

Showing result 1 - 5 of 10 swedish dissertations containing the word mode-matching.

  1. 1. Effective vibro-acoustical modelling of rubber isolators

    University dissertation from Stockholm : KTH

    Author : Michael Coja; KTH.; [2005]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Applied mechanics; Rubber isolator; Bush mounting; Dynamic stiffness; Waveguide; Fractional derivatives; Mode-matching; Pre-compressed; Prestrain; Preload; Predeformation; Viscoelasticity; Dispersion; Teknisk mekanik; TECHNOLOGY Engineering mechanics; TEKNIKVETENSKAP Teknisk mekanik;

    Abstract : This thesis, gathering four papers, concerns the enhancement in understanding and modelling of the audible dynamic stiffness of vibration rubber isolators including experimental measurements.Paper A studies the performances of three different types of vibration isolator using an indirect measurement technique to estimate the blocked dynamic transfer stiffness of each specimen. READ MORE

  2. 2. Periodic Structures with Higher Symmetries: Analysis and Applications

    University dissertation from Stockholm : KTH Royal Institute of Technology

    Author : Fatemeh Ghasemifard; KTH.; [2018]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; periodic structures; higher symmetries; dispersion analysis; mode matching; generalized Floquet theorem; Electrical Engineering; Elektro- och systemteknik;

    Abstract : In this thesis, periodic structures with higher symmetries are studied. Their wave propagation characteristics are investigated and their potential applications are discussed. Higher-symmetric periodic structures are described with an additional geometrical operation beyond a translation operator. READ MORE

  3. 3. Modelling of compact resonators

    University dissertation from Institutionen för farkostteknik

    Author : Pierre-Luc Regaud; KTH.; [2001]
    Keywords : Acoustic; Resonator compact; Fold; End correction; Spiral; Helical; Higher order modes; 2-port; Side-branch; Mode matching; Collocation; Weak formulation; Harmonic;

    Abstract : .... READ MORE

  4. 4. Thick Frequency Selective Structures

    University dissertation from Department of Electroscience, Lund University

    Author : Björn Widenberg; [2003]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; acoustics; Elektromagnetism; optik; akustik; optics; Electromagnetism; Energy Saving Window; Radome; Finite Elemente Method; Frequency Selective Structure; Mode Matching Technique;

    Abstract : This thesis presents a new method that can handle a general thick Frequency Selective Structure (FSS), that consists of an arbitrary number of aperture layers and dielectric layers. The method is based on the Mode Matching Technique (MMT) and the finite element method (FEM). The thesis consists of a General Introduction and five scientific papers. READ MORE

  5. 5. Online power transformer diagnostics using multiple modes of microwave radiation

    University dissertation from Stockholm : KTH Royal Institute of Technology

    Author : Mariana Dalarsson; KTH.; [2013]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; inverse problem; multiple modes; power transformers;

    Abstract : In the present thesis, we propose and investigate a new approach to diagnose the effects of the various degradation mechanisms, including thermal degradation at hot spots, winding deformations due to the mechanical forces from short circuit currents, partial discharges due to local electric field surges, and increased moisture levels in the cellulose insulation due to decomposition, that affect electric power transformers during their normal operation in an electric power grid.Although the proposed diagnostics method can in principle be used to detect various degradation mechanisms mentioned above, we focus in the present thesis on mechanical deformations of transformer winding structures. READ MORE