Search for dissertations about: "scattering matrix"

Showing result 1 - 5 of 138 swedish dissertations containing the words scattering matrix.

2. 1. Scattering of elastic waves by an anisotropic sphere

   Author : Ata Jafarzadeh; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Sphere; T matrix; Effective wave number; Distribution of inclusions; Phase velocity.; Anisotropy; Attenuation; Scattering;

   Abstract : Scattering of a plane wave by a single spherical obstacle is the archetype of many scattering problems in physics and geophysics. Spherical objects can provide a good approximation for many real objects, and the analytic formulation for a single sphere can be used to investigate wave propagation in more complicated structures like particle composites or grainy materials, which may have application in non-destructive testing, material characterization, medical ultrasound, etc. READ MORE

4. 2. Scattering of elastic waves by an anisotropic sphere with application to polycrystalline materials

   Author : Ata Jafarzadeh; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Spherical obstacle; Anisotropy; Attenuation; Polycrystalline materials; Effective wave number; T matrix; Phase velocity; Scattering;

   Abstract : Scattering of a plane wave by a single spherical obstacle is the archetype of many scattering problems in various branches of physics. Spherical objects can provide a good approximation for many real objects, and the analytic formulation for a single sphere can be used to investigate wave propagation in more complex structures like particulate composites or grainy materials, which may have applications in non-destructive testing, material characterization, medical ultrasound, etc. READ MORE

5. 3. Assessing precision and accuracy in acoustic scattering matrix measurements

   Author : Luck Peerlings; Hans Bodén; Susann Boij; Avraham Hirschberg; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; aero-acoustics; sudden area expansion; in-duct acoustics; acoustic scattering matrix; impedance tube; uncertainty analysis; systematic errors; Vehicle and Maritime Engineering; Farkostteknik;

   Abstract : Acoustic scattering matrices are used to characterize the influence of inline duct elements on the acoustic wave propagation in wave guides.When measuring the properties of these matrices, errors are always present in the results and need to be characterized to make valid statements on the correspondence between model predictions and measurements. READ MORE

6. 4. Rough Scatterers in Acoustics and Elastodynamics

   Author : Per-Åke Jansson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; acoustic scattering; penny-shaped crack; rough surfaces; elastodynamic scattering; T matrix; null field approach;

   Abstract : The purpose of this thesis is to investigate the influence of roughness on wave scattering from finite-sized surfaces, in particular elastic wave scattering from cracks. Acoustic scattering from a sphere is considered using the null field approach. READ MORE

7. 5. Analytical methods of solution to eddy current interaction problems

   Author : Lars Larsson; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Boundary integral equation; Scattering; T matrix; Eddy current; Nondestructive evaluation;

   Abstract : The eddy current method is used for nondestructive evaluation of conducting materials. To achieve a greater knowledge and insure safe and reliable evaluation methods, the use of mathematical models is needed. READ MORE