Sökning: "Cylindrical"

Visar resultat 1 - 5 av 291 avhandlingar innehållade ordet Cylindrical.

1. 1. Waveguide slot antennas with cylindrical outer structures

   Författare :Johan Wettergren; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cylindrical structures; arbitrary cross sections; waveguide slots; two-dimensional solutions; slot admittance; cylindrical antennas; moment method; slot antennas; spectral domain; cylindrical geometries;

   Sammanfattning : .... LÄS MER

3. 2. Analysis of Dipole and Patch Antennas in Cylindrical Structures

   Författare :Peter Slättman; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fourier transform; cross-section; patch; slot; arbitrary; EFIE; trough guide; cylindrical; dipole; moment method; antenna; aperture coupled;

   Sammanfattning : This thesis deals with the analysis of dipoles, patches, and aperture coupled patches located in an infinitely long cylindrical structure with arbitrary cross-section. The analysis exploits the two-dimensional nature of the structure by expanding all fields and currents in spatial harmonics along the cylinder axis, and solving the subsequent spectral two-dimensional problems by the moment method. LÄS MER

4. 3. Impact of Metallic Projectiles on a Ceramic Target Surface : Transition Between Interface Defeat and Penetration

   Författare :René Renström; Bengt Lundberg; Patrik Lundberg; Nils-Gunnar Ohlson; Uppsala universitet; []
   Nyckelord :Engineering physics; Projectile; Cylindrical; Conical; Yield strength; Compressibility; Perfect flow; Self-similar flow; Interface defeat; Dwell; Teknisk fysik; Teknisk fysik med inriktning mot hållfasthetslära; Engineering Science with specialization in Solid Mechanics;

   Sammanfattning : The purpose of this thesis is to gain understanding of the load on flat target surfaces produced by projectile impact. Models are proposed from which upper and lower bounds can be derived for the transition be-tween interface defeat and normal penetration. LÄS MER

5. 4. Buoy Geometry, Size and Hydrodynamics for Power Take Off Device for Point Absorber Linear Wave Energy Converter

   Författare :Halvar Gravråkmo; Mats Leijon; Jan Isberg; Luke Myers; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; point absorber; wave; energy; converter; ocean; wec; toroidal; buoy; torus; cylindrical; cylinder; experiment; full scale; trial; sea; energy; renewable; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

   Sammanfattning : Wave energy converters of point absorber type have been developed and constructed. Full scale experiments have been carried out at sea and electricity has been successfully delivered. Linear permanent magnet generators together with a subsea substation and buoys of various geometric shapes have been investigated theoretically and experimentally. LÄS MER

7. 5. Cylindrical Waveguide Slot Antenna Analysis

   Författare :Johan Wettergren; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; basis function; mutual admittance; cylinder; MPIE; slot; integral equation; waveguide; antenna; mutual coupling; moment method; EFIE;

   Sammanfattning : Waveguide slot antennas with longitudinal and transverse slots are analyzed using a rigorous method. The antennas are divided into regions, which are analyzed separately and matched by a moment method procedure. At the apertures between the regions, the electric fields are expanded in trigonometric basis functions. LÄS MER