Sökning: "high frequencies"
Visar resultat 1 - 5 av 774 avhandlingar innehållade orden high frequencies.
1. High-Efficiency SiC Power Conversion : Base Drivers for Bipolar Junction Transistors and Performance Impacts on Series-Resonant Converters
Sammanfattning : This thesis aims to bring an understanding to the silicon carbide (SiC) bipolar junction transistor (BJT). SiC power devices are superior to the silicon IGBT in several ways. They are for instance, able to operate with higher efficiency, at higher frequencies, and at higher junction temperatures. LÄS MER
2. High frequency electronic packaging : SBU-materials, material characterization, simulation and processing
Sammanfattning : Electronic packaging continues to move towards improved performance and lower cost. Requirements of higher performance, reduced size, weight and cost of both High Density Interconnects (HDI) and high frequency (HF) devices has led to the search for new: materials, material combinations, methods, processes and production equipment. LÄS MER
3. Temporal Aspects of High-Intensity Laser-Matter Interactions
Sammanfattning : The availability of short-pulse, high-intensity lasers has opened doors to new areas in atomic and plasma physics. The short pulses (a few femtoseconds), that are available today, enable unprecedented temporal measurements, while the high peak power accessible (several terawatts) allows physicists to study the interaction between light and relativistic plasmas. LÄS MER
4. High Frequency Tyre Vibrations
Sammanfattning : High frequency (above 1 kHz) noise generation from the tyre/road interaction is still not fully understood and accurately modelled.Two noise generation mechanisms previously suggested in the literature are reviewed: air pumping and noise generation cased by adhesive effects between the tyre tread and road surface. LÄS MER
5. Nanostructured electromagnetic metasurfaces at optical frequencies
Sammanfattning : Electromagnetic metasurfaces are broadly defined as optically thin layersthat are structured on the subwavelength scale. In general, metasurfacesthus consist of nanoparticles, or other kinds of ”meta-atom”, arranged insome pattern where both the individual particle sizes and the inter-particledistances are much smaller than the wavelength. LÄS MER