Sökning: "wave splitting"

Visar resultat 21 - 25 av 43 avhandlingar innehållade orden wave splitting.

1. 21. Analyses of Seismic Wave Conversion in the Crust and Upper Mantle beneath the Baltic Shield

   Författare :Sverker Olsson; Roland Roberts; Hans Thybo; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geophysics; converted waves; Moho; upper mantle; Baltic Shield; tomography; anisotropy; receiver function; Geofysik;

   Sammanfattning : Teleseismic data recorded by broad-band seismic stations in the Swedish National Seismic Network (SNSN) have been used in a suite of studies of seismic wave conversion in order to assess the structure of the crust and upper mantle beneath the Baltic Shield. Signals of seismic waves converted between P and S at seismic discontinuities within the Earth carry information on the velocity contrast at the converting interface, on the depth of conversion and on P and S velocities above this depth. LÄS MER

3. 22. Quantum acoustics with propagating phonons

   Författare :Maria Ekström; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; phonon router; unidirectional transducer; phonon; Electromagnetically Induced Transparency; Surface acoustic wave; artificial atom; interdigital transducer; quantum acoustics; qubit; superconducting circuits;

   Sammanfattning : Surface acoustic waves (SAWs) are mechanical vibrations that propagate on the surface of solids while dissipating little power, consequently enabling them to propagate freely over long distances. The speed and wavelength of SAWs are reduced a five order of magnitude compared to when light is used as a carrier at gigahertz frequencies. LÄS MER

4. 23. On signal processing and electromagnetic modelling : applications in antennas and transmission lines

   Författare :Jonas Lundbäck; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Vector sensors; Statistical signal processing; Antennas; Directional Coupler; Tranmission lines; Partial discharge;

   Sammanfattning : This doctoral thesis is comprised of five parts. The first three parts concern signal processing and electromagnetic modelling of multiport antennas. The last two parts concern signal processing and transmission line theory applied to wave splitting on transmission lines. LÄS MER

5. 24. Adiabatic guiding of matter waves

   Författare :Markku Jääskeläinen; KTH; []
   Nyckelord :;

   Sammanfattning : Recent efforts in the field of ultracold atoms have goneinto creating wave guides of sub-micron sizes. In this thesis,the quantum dynamics of matter waves in such confiningpotential structures with minima extended in space isinvestigated. LÄS MER

7. 25. Solving the quantum scattering problem for systems of two and three charged particles

   Författare :Mikhail Volkov; Nils Elander; William McCurdy; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Scattering theory; three body scattering; Atomic and molecular physics; Atom- och molekylfysik; Mathematical physics; Matematisk fysik; fysik; Physics;

   Sammanfattning : A rigorous formalism for solving the Coulomb scattering problem is presented in this thesis. The approach is based on splitting the interaction potential into a finite-range part and a long-range tail part. In this representation the scattering problem can be reformulated to one which is suitable for applying exterior complex scaling. LÄS MER