Sökning: "Vector Field Method"

Visar resultat 6 - 10 av 76 avhandlingar innehållade orden Vector Field Method.

1. 6. Sound Field Design for Transducer Array-Based Acoustic Levitation

   Författare :Carl Andersson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Nonlinear Acoustics; Sound Field Design; Transducer Arrays; Acoustic Levitation; Numerical Optimization;

   Sammanfattning : Acoustic levitation is a technique where sound waves are used to hold an object at a designated position, suspending it against other external forces and keeping it stable in the desired position. Transducer arrays are an arrangement of many loudspeaker elements, tuned such that the array creates a sound field that is too complicated for the individual elements to produce on their own. LÄS MER

3. 7. Time Domain Boundary Element Methods for Acoustic Scattering

   Författare :Georgios Natsiopoulos; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; time domain; curved surface; room acoustics; boss model; boundary element method; regularization; transient; Hermite interpolation; hypersingular; acoustic scattering; vector potential;

   Sammanfattning : In room acoustics, numerical computation of scattering phenomena is an important subject, since it is needed to accurately predict the influence of reflectors, the audience, balconies, etc, on the perceived acoustic quality of auditoria. The large physical volumes of auditoria and the wide frequency content of music and speech, together with the complicated geometries involved however, makes predictions in room acoustics a challenging task from a computational point of view. LÄS MER

4. 8. Structural Information Content of the Optical Field

   Författare :Per Martinsson; Ari Friberg; Karl-Heinz Brenner; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Photonics; Fotonik;

   Sammanfattning :  The communication modes are a mathematical technique for the description of structural information in optical fields. These modes are orthogonal, optimally  connected functions characteristic of the optical system. Mathematically they are obtained by the singular value decomposition (SVD) of the operator that represents the field propagation. LÄS MER

5. 9. Experimental verification of tomographic measurement methods in ultrasound

   Författare :Monica Almqvist; Avdelningen för Biomedicinsk teknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; airborne.; high resolution; characterization; tomography; light diffraction; doppler; ultrasound; vector tomography; Instrumentation technology; Mät- och instrumenteringsteknik;

   Sammanfattning : This thesis describes two different measurement methods applied to ultrasound. The first method, Ultrasound doppler vector tomography, uses ultrasound to measure blood flow and the second method, Light diffraction tomography, measures the pressure field in an ultrasound beam with laser light. LÄS MER

7. 10. Design, Modelling and Control of Electrical Machines - With Applications to Iron-powder Machines and Acoustic Noise

   Författare :David Martinez; Industriell elektroteknik och automation; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; BEM; induction machine; noise prediction; vector control; acoustic noise; HEV; series magnetization; leakage reduction; thermal model; FEM; MEC; claw-poles; SMC; slip-ring-less machine; sound intensity measurements; vibration; Electrical engineering; Elektroteknik;

   Sammanfattning : This thesis consists of two parts, the first dealing with the design of iron-powder synchronous machines, and the second with the analysis and prediction of the acoustic noise in electrical machines. In Part I, a 1.6 kW electrically magnetized claw-pole machine with magnetically conducting end-plates has been analyzed and a prototype tested. LÄS MER