Sökning: "high effciency"

Hittade 5 avhandlingar innehållade orden high effciency.

  1. 1. Towards Gap Waveguide Array Antenna for Millimeter Wave Applications

    Författare :Abbas Vosoogh; Chalmers University of Technology; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; gap waveguide; Electric Discharge Machining EDM ; Artificial Magnetic Conductor AMC ; slot array antenna; low sidelobe; high effciency; millimeter wave; aperture efficiency; Bandpass filter BPF ;

    Sammanfattning : The millimeter wave frequency range has got a lot of attention over the past few years because it contains unused frequency spectrum resources that are suitable for delivering Gbit/s end-user access in areas with high user density. Due to the limited output power that current RF active components can deliver in millimeter waves, antennas with the merits of low profile, high gain, high effciency and low cost are needed to compensate free space path loss and increase the communication distance for the emerging high data rate wireless systems. LÄS MER

  2. 2. Diluted Operation of a Heavy-Duty Natural Gas Engine - Aiming at Improved Effciency, Emission and Maximum Load

    Författare :Mehrzad Kaiadi; Förbränningsmotorer; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulence; Natural gas engine; Dilution limit; VGT; Cyclic variation; Closed-loop control; Heavy-duty;

    Sammanfattning : Most heavy-duty engines are diesel operated. Severe emission regulations, high fuel prices, high technology costs (e.g. catalysts, fuel injection systems) and unsustainably in supplying fuel are enough reasons to convenience engine developers to explore alternative technologies or fuels. LÄS MER

  3. 3. Aerodynamic design framework for low-pressure compression systems

    Författare :Marcus Lejon; Chalmers University of Technology; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; manufacturing variations; optimization; stage matching; tip clearance; validation; Turbomachinery; CFD; surface roughness; compressor;

    Sammanfattning : Aircraft engine manufacturers strive to improve current state of the art designs through continuous development efforts. By improving existing designs and exploring new alternatives, the goal is to reduce the fuel consumption - a topic of high relevance due to the remarkable growth rate of air traffc. LÄS MER

  4. 4. Self-Homodyne Coherent Systems using Advanced Modulation Formats

    Författare :Martin E Sjödin; Chalmers University of Technology; []

    Sammanfattning : Modulation formats that offer high spectral efficiency will be of great importance in future fiber optic communication systems. Currently, a lot of research effortsare ongoing to investigate the best ways of generating and detecting modulation formats in which both the phase and the amplitude of the light are used to carry information, such as 16-QAM. LÄS MER

  5. 5. Protein based approaches for further development of the pyrosequencing technology platform

    Författare :Maria Ehn; KTH; []
    Nyckelord :pyrosenquencing; ssb; zbasic; klenow; apyrase; expression; purification;

    Sammanfattning : The innovation of DNA analysis techniques has enabled arevolution in the field of molecular biology. In the 70’s,first technologies for sequence determination of DNA wereinvented and these techniques enormously increased thepossibilities of genetic research. LÄS MER