Sökning: "mode estimation"

Visar resultat 1 - 5 av 115 avhandlingar innehållade orden mode estimation.

1. 1. Resonant magnetic perturbation effect on the tearing mode dynamics : Novel measurements and modeling of magnetic fluctuation induced momentum transport in the reversed-field pinch

   Författare :Richard Fridström; Per Brunsell; Lorenzo Frassinetti; Tommaso Bolzonella; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; RFP; reversed-field pinch; tokamak; tearing mode; RMP; fusion; plasma; resonant magnetic perturbation; stochastic; magnetic; field; viscosity; mode; locking; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : The tearing mode (TM) is a resistive instability that can arise in magnetically confined plasmas. The TM can be driven unstable by the gradient of the plasma current. When the mode grows it destroys the magnetic field symmetry and reconnects the magnetic field in the form of a so-called magnetic island. LÄS MER

3. 2. Non-intrusive Methods for Mode Estimation in Power Systems using Synchrophasors

   Författare :Vedran Peric; Luigi Vanfretti; Xavier Bombois; Cristian Rojas; Mani V. Venkatasubramanian; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Synchrophasors; Phasor measurement units; system identification; mode estimation; electromechanical oscillations; prediction error; signal selection; experiment design; probing; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : Real-time monitoring of electromechanical oscillations is of great significance for power system operators; to this aim, software solutions (algorithms) that use synchrophasor measurements have been developed for this purpose. This thesis investigates different approaches for improving mode estimation process by offering new methods and deepening the understanding of different stages in the mode estimation process. LÄS MER

4. 3. Channel Estimation in Wireless Communication Systems Employing Multiple Antennas

   Författare :Mikael Coldrey; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; multiple antennas; capacity; channel estimation; non-parametric estimation; training; distributed sources; MIMO; Wireless communications; superimposed pilots; performance bounds;

   Sammanfattning : Antennas that are able to adaptively direct the transmitted (and received) energy are of great interest in future wireless communication systems. The directivity implies reduced transmit power and interference, and also a potential for increased capacity. LÄS MER

5. 4. Signal Processing for Spectroscopic Applications

   Författare :Erik Gudmundson; Peter Stoica; Peter Händel; Stoica Stoica; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; spectral estimation; spectroscopic techniques; MRI; NMR; NQR; signal detection; parameter estimation; missing data; non-uniform sampling; damped sinusoids; detection of explosives; T1-mapping; relaxometry; brain imaging; skin imaging; blood velocity estimation; medical ultrasound; Signal processing; Signalbehandling; Elektroteknik med inriktning mot reglerteknik; Electrical Engineering with specialization in Automatic Control;

   Sammanfattning : Spectroscopic techniques allow for studies of materials and organisms on the atomic and molecular level. Examples of such techniques are nuclear magnetic resonance (NMR) spectroscopy—one of the principal techniques to obtain physical, chemical, electronic and structural information about molecules—and magnetic resonance imaging (MRI)—an important medical imaging technique for, e. LÄS MER

7. 5. Estimation of synchronization parameters

   Författare :Jaap van de Beek; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Signalbehandling; Signal Processing;

   Sammanfattning : This thesis deals with the estimation of synchronization parameters in {Orthogonal Frequency Division Multiplexing} (OFDM) communication systems and in active ultrasonic measuring systems. Estimation methods for the timing and frequency offset and for the attenuation taps of the frequency selective channel are presented and investigated. LÄS MER