Sökning: "frequency conversion"

Visar resultat 6 - 10 av 194 avhandlingar innehållade orden frequency conversion.

1. 6. Electric Energy Conversion Systems : Wave Energy and Hydropower

   Författare :Karin Thorburn; Mats Leijon; Petra Lundström; Uppsala universitet; []
   Nyckelord :Engineering physics; Ocean wave power; renewable energy; linear generator; farm simulation; Teknisk fysik;

   Sammanfattning : Electric energy conversion is an important issue in today's society as our daily lives largely depend on the supplies of energy. Two energy sources are studied for conversion in the present thesis, ocean waves and hydropower. The work focuses on the generator and the transmission of its output to the electric grid. LÄS MER

3. 7. Silicon Integrated HBV Frequency Multipliers for THz Applications

   Författare :Aleksandra Malko; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; frequency multipliers; Heterostrucutre Barrier Varactors HBVs ; THz sources; wafer bonding.; integrated circuits; heterogeneous integration; Compund semiconductors; epitaxial transfer; MICs;

   Sammanfattning : This thesis deals with integrated varactor diode circuits for terahertz (THz) applications. In particular hybrid, monolithic microwave integrated circuits (MMICs), and heterogeneous integration are explored for frequency multiplier applications. LÄS MER

4. 8. Gene conversion of the mouse MHC class II

   Författare :Kari Högstrand; Ulf Gyllensten; Stockholms universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MHC; H2; gene conversion; evolution; polymorphism; Immunology; Immunologi; immunologi; Immunology;

   Sammanfattning : The major histocompatibility complex (MHC) is the most polymorphic vertebrate gene loci known to exist. Gene products of the MHC are responsible for presentation of antigen derived peptides to T cells of the immune system, which thereby become activated and involved in the elimination of particles recognised as non-self. LÄS MER

5. 9. Heterostructure Barrier Varactors for High Efficiency Frequency Multipliers

   Författare :Lars Dillner; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; frequency multiplier; Heterostructure Barrier Varactor HBV ; millimeter wave; submillimeter wave; power source;

   Sammanfattning : This thesis describes the Heterostructure Barrier Varactor (HBV) and its application in frequency multipliers. Different HBV materials, fabrication processes, and device models are presented. The aim of this work is to improve the efficiency of HBV frequency multipliers. LÄS MER

7. 10. Millimetre wave waveguide enclosed grid frequency multipliers and imaging

   Författare :Robin Dahlbäck; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Millimeter wave; THz imaging; THz sources; Grid; Heterostructure Barrier Var- actors HBVs ; Varactors; Array; FMCW; 2D-grid; Quasi-optical.; Frequency multipliers; Radars; sub-millimetre waves; Schottky diodes;

   Sammanfattning : The utilisation of the THz spectrum ( 0.3-10 THz ) is hampered by fundamental difficulties in generating power at these frequencies. LÄS MER