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Visar resultat 1 - 5 av 29 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Analysis and Design of Conformal Array Antennas

   Författare :Patrik Persson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Conformal antennas; conformal arrays; UTD; high frequency method; MoM; hybrid method; mutual coupling; singly curved surface; doubly curved surface; geodesics; dielectric covered circular cylinder; non-paraxial region. paraxial region; waveguide fed; Electrical engineering; Elektroteknik;

   Sammanfattning : Today there is a great need for communication between people and even between things, using systems onboard e.g. aircraft, cars, ships and satellites. As a consequence, these communications needs require antennas mounted on or integrated in the surfaces of different vehicles or platforms, i. LÄS MER

3. 2. Computation of EMC Properties of Slots and Printed Circuit Boards

   Författare :Jan Carlsson; RISE; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; corrugations; crosstalk; FDTD; spectral domain; EFIE; chokes; Finite Difference Method; printed circuit board; transmission line network; EMC analysis; PCB; transmission line theory; radiated emission; Method of moments; MM; MoM; electric field integral equation; soft and hard surfaces; slot; radiated susceptibility;

   Sammanfattning : This thesis deals with the numerical solution of electromagnetic compatibility (EMC) problems for electronic systems, such as radiated emission, susceptibility and crosstalk on printed circuit boards and transmission through slots. The analysis of printed circuit boards is done by using an electric field integral equation (EFIE) expressed in the frequency domain, which is solved by using the method of moments. LÄS MER

4. 3. Computational Tools for Antenna Analysis and Design

   Författare :Doruk Tayli; Teoretisk elektroteknik; []
   Nyckelord :Antenna theory; Fundamental bounds; method of moments MoM ; Characteristic modes; macro basis functions MBFs ; adaptive cross approximation ACA ; endfire arrays;

   Sammanfattning : Many engineers and scientists prevalently use computational tools in electromagnetics, which is also the predominant case for antennas. The ever-increasing number of applications and technologies that employ antennas create a constant demand to improve and extend existing tools and develop new ones. LÄS MER

5. 4. Evaluation of a metal-on-metal total hip arthroplasty

   Författare :Henrik Dahlstrand; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :;

   Sammanfattning : Background: After the introduction of the Metasul system by Weber in 1988, total hip arthroplasty (THA) with metal-on-metal (MoM) bearings became increasingly popular in the 1990s. MoM bearings aimed to reduce the problem of aseptic loosening associated with polyethylene wear particles from conventional polyethylene cups. LÄS MER

7. 5. Bax and oxidized phospholipids - a deadly complex : Apoptotic protein-lipid assemblies studied by MAS NMR spectroscopy

   Författare :Artur Dingeldein; Gerhard Gröbner; Mikael Elofsson; Tobias Sparrman; Daniel Topgaard; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NMR spectroscopy; mitochondrial membranes; apoptosis; membrane dynamics and organization; Bcl-2 family proteins; Bax protein; biokemi; Biochemistry;

   Sammanfattning : Mitochondria are renowned for their vital role as cellular powerhouses because they provide ATP via cellular respiration. Additionally, these organelles also play an important role in other physiological processes, such as apoptosis. LÄS MER