Sökning: "natural frequency analysis"

Visar resultat 16 - 20 av 369 avhandlingar innehållade orden natural frequency analysis.

1. 16. Electromagnetic dispersion modeling and analysis for HVDC power cables

   Författare :Stefan Gustafsson; Sven Nordebo; Martin Norgren; Linnéuniversitetet; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; HVDC power cables; electromagnetic model; TDR measurement; sensitivity analysis; dispersion relation; propagation constant; low-frequency asymptotics;

   Sammanfattning : Derivation of an electromagnetic model, regarding the wave propagation in a very long (10 km or more) High Voltage Direct Current (HVDC) power cable, is the central part of this thesis. With an existing “perfect” electromagnetic model there are potentially a wide range of applications. LÄS MER

3. 17. A periodically Ordered Structures in One Dimension

   Författare :Michael Hörnquist; Mads Peter Sørensen; Linköpings universitet; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : This thesis deals with different aspects of aperiodically ordered structures in one dimension. The approach is entirely theoretical, and the models used have various relevance for real systems. LÄS MER

4. 18. Optical sensors in drinking water production : Towards automated process control in relation to natural organic matter

   Författare :Claudia Cascone; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :NATURVETENSKAP; NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : Access to safe and clean drinking water is a basic human right (A/RES/64/292). In Sweden, large drinking water treatment plants use mainly surface water as water source. The long-term trend of increasing natural organic matter (NOM) in boreal and north European surface waters negatively affects the overall performance of the treatment processes. LÄS MER

5. 19. Computational electromagnetics : software development and high frequency modeling of surface currents on perfect conductors

   Författare :Sandy Sefi; Jesper Oppelstrup; Francisco Saez de Adana; KTH; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; High frequency approximations; Maxwell’s equations; Method of Moments; Physical Optics; Geometrical Theory of Diffraction; Extraction Extrapolation; Numerical analysis; Numerisk analys;

   Sammanfattning : In high frequency computational electromagnetics, rigorous numerical methods be come unrealistic tools due to computational demand increasing with the frequency. Instead approximations to the solutions of the Maxwell equations can be employed to evaluate th electromagnetic fields. LÄS MER

7. 20. On MIMO Systems and Adaptive Arrays for Wireless Communication : Analysis and Practical Aspects

   Författare :Mattias Wennström; Michael A. Jensen; Uppsala universitet; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Systemteknik; antenna array; calibration; MIMO system; flat fading; non-linear amplifier; switched parasitic antenna; analog beamformer; adaptive antenna testbed; Systemteknik; Systems engineering; Systemteknik; Signal Processing; signalbehandling;

   Sammanfattning : This thesis is concerned with the use of multiple antenna elements in wireless communication over frequency non-selective radio channels. Both measurement results and theoretical analysis are presented. New transmit strategies are derived and compared to existing transmit strategies, such as beamforming and space-time block coding (STBC). LÄS MER