Sökning: "frequency"

Visar resultat 16 - 20 av 5211 avhandlingar innehållade ordet frequency.

1. 16. Dynamics and Extreme Value Problems for Moored Floating Platforms

   Författare :Yungang Liu; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; quasi-static; frequency-domain; extreme value; convolution; floating platform; low-frequency; time-domain; mooring cable; wave-frequency;

   Sammanfattning : This research deals with the dynamic response analyses and extreme value problems of moored floating platforms. It can be divided into three major subjects: first, the analysis of single cables and cable induced mooring damping; second, the dynamic analysis of the moored platforms, with special emphasis on the damping mechanisms and generation of the low-frequency excitation force time series; and third, the extreme wave-frequency responses and the combination of the low-frequency and wave-frequency extreme responses. LÄS MER

3. 17. High frequency electronic packaging : SBU-materials, material characterization, simulation and processing

   Författare :Christian Johansson; Hjalmar Hesselbom; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; dielectric loss; high frequency electrical characterization; microwave circuits; multilayer thin film technology; ORMOCER; permittivity; sequential build up; silicone elastomer;

   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

4. 18. Modeling and Control of Voltage Source Converters Connected to the Grid

   Författare :Michael Lindgren; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; voltage source converter; switching frequency; pulse width modulation; IGBT valve; power electronics; small-signal; L-filter; LCL-filter; transfer function; line filter; active filtering; frequency response; sampling frequency;

   Sammanfattning : This thesis deals with the modeling and control of pulse width modulated (PWM) voltage source converters connected to the grid. When voltage source converters are connected to the grid, the power quality and the dynamic performance are affected by the line filter connected between the converter and the grid, and by nonlinearities caused by the switching converter. LÄS MER

5. 19. Frequency stable diode lasers in atomic physics and fundamental metrology

   Författare :Johan Åman; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Iodine; semiconductor laser; frequency standard; frequency stabilisation; Calcium; length standard; fundamental metrology; extended cavity; experimental atomic physics;

   Sammanfattning : .... LÄS MER

7. 20. Impact of adjacent dielectrics on the high-frequency performance of graphene field-effect transistors

   Författare :Muhammad Asad; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high-frequency electronics; Graphene; transit frequency; contact resistance; MOGFETs; drift velocity; field-effect transistors; saturation velocity; maximum frequency of oscillation; diamond;

   Sammanfattning : Transistors operating at high frequencies are the basic building blocks of millimeter wave communication and sensor systems. The high velocity and mobility of carriers in graphene can open ways for development of ultra-fast group IV transistors with similar or even better performance than that achieved with III-V based semiconductors. LÄS MER