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Visar resultat 1 - 5 av 126 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Efficient Electromagnetic Induction Modelling : Adaptive mesh optimisation, advanced boundary methods and iterative solution techniques

   Författare :Laura M. Buntin; Thomas Kalscheuer; Gunilla Kreiss; Zhengyong Ren; Klaus Spitzer; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Applied geophysics; Electromagnetic theory; Numerical Modelling; Geo-Electromagnetics; Magnetotellurics; Controlled-source electromagnetics; Goal-oriented adaptive mesh refinement; Perfectly-matched layers; Iterative solution methods; Preconditioning; Geofysik med inriktning mot fasta jordens fysik; Geophysics with specialization in Solid Earth Physics;

   Sammanfattning : Forward modelling of electromagnetic induction data simulates the electric and magnetic fields within a computational domain for a given distribution of electromagnetic material properties and a given source of the electromagnetic field. The quantities of interest are the fields at receiver locations at the Earth's surface. LÄS MER

3. 2. Electromagnetic Interference in Distributed Outdoor Electrical Systems, with an Emphasis on Lightning Interaction with Electrified Railway Network

   Författare :Nelson Theethayi; Rajeev Thottappillil; Farhad Rachidi; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical engineering; Electromagnetic Compatibility EMC ; Lightning; Lightning Protection; Transmission Lines; Electromagnetic Wave Propagation; Underground Cables; Grounding; Electromagnetic Transients; Electromagnetic Interference; Shielding Effectiveness; Railway Systems; Elektroteknik; elektronik och fotonik; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

   Sammanfattning : This thesis deals with the electromagnetic compatibility (EMC) problems of distributed electrical networks, especially that caused by lightning to electrified railway. Lightning transients were found to damage important devices that control train movements, causing traffic stoppage and delays. LÄS MER

4. 3. Design and Characterization of Functional Structures for Electromagnetic Waves

   Författare :Andreas Ericsson; Teoretisk elektroteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electromagnetic scattering; functional structure; circular polarization selective structure; reflector antenna; electromagnetic absorber; radar cross section; compressive sensing; triaxial weave; homogenization; physical optics;

   Sammanfattning : This dissertation deals with design and characterization of functional structures for scattering of electromagnetic waves. An abundance of these structures can be found in nature, such as the structural coloration in the feathers of a peacock, the scales of butterflies and the shell of scarab beetles. LÄS MER

5. 4. Electromagnetic and Spin Properties of Hyperons

   Författare :Elisabetta Perotti; Stefan Leupold; Luis Alvarez Ruso; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Electromagnetic form factors; hyperon physics; dispersion relations; QCD; chiral perturbation theory; CP violation; Fysik; Physics;

   Sammanfattning : The study of hyperons improves our understanding of nature in multiple ways. The intrinsic properties of hadrons are not fully understood at a fundamental level. Hence, the electromagnetic properties of hyperons provide complementary information to that of the nucleon and therefore allow for a broader investigation of the structure of matter. LÄS MER

7. 5. Transport theory and finite element methods for mesoscopic superconducting devices

   Författare :Kevin Marc Seja; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; non-equilibrium superconductivity; finite element methods; unconventional superconductors; quasiclassical theory; transport theory;

   Sammanfattning : At low temperatures, electrons in a superconductor exhibit pairing correlations that result in a macroscopic, phase-coherent ground state. This leads to peculiar electromagnetic properties such as the flow of dissipationless charge currents and expelling of external magnetic fields. LÄS MER