Search for dissertations about: "mode-matching"

Showing result 1 - 5 of 9 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. Modern numerical methods in electromagnetics applied to the design of reflector antennas and horn feeds

    University dissertation from Chalmers University of Technology

    Author : Martin Johansson; Chalmers tekniska högskola.; Chalmers University of Technology.; [1994]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; corrugated horn; dual-frequency; dual-band; low noise; very long baseline interferometry; VLBI; finite element method; mode matching; coaxial waveguide; circular waveguide; reflector antenna; offset; dual-reflector feed; physical optics; cluster feed; ray tracing; diffraction;

    Abstract : .... 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; Lunds universitet.; Lund University.; [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 : Popular Abstract in Swedish Denna avhandling presenterar en metod som kan hantera generella tjocka frekvensselektiva strukturer (FSS). Metoden är baserad på modanpassning och finita elementmetoden (FEM). Avhandlingen är en sammanläggningsavhandling och består av en introduktion som följs av fem vetenskapliga artiklar. 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