Sökning: "resonance frequency analysis."

Visar resultat 21 - 25 av 98 avhandlingar innehållade orden resonance frequency analysis..

1. 21. Ferromagnetic Resonance as a Probe of Magnetization Dynamics : A Study of FeCo Thin Films and Trilayers

   Författare :Yajun Wei; Peter Svedlindh; Sujeet Chaudhary; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ferromagnetic resonance FMR ; Gilbert damping; magnetic coupling; FeCo;

   Sammanfattning : The high frequency dynamic magnetic responses of FeCo thin films and structures have been investigated mainly using ferromagnetic resonance (FMR) technique.The FMR resonance condition and linewidth are first derived from the dynamic Landau- Lifshitz-Gilbert equation, followed by a study of the conversion between FMR field and frequency linewidths. LÄS MER

3. 22. ROBUST DETECTION AND SPECTRAL ANALYSIS OF SIGNALS WITH APPLICATIONS IN SPECTROSCOPY

   Författare :Naveed Butt; Matematisk statistik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Detection; NQR; NMR; Raman Spectroscopy; Spectral Analysis.;

   Sammanfattning : Modern spectroscopic techniques, such as nuclear quadrupole resonance (NQR), nuclear magnetic resonance (NMR), and Raman spectroscopy, rely heavily on statistical signal processing systems for decision making and information extraction. The first part of this thesis introduces novel robust algorithms for detection, estimation, and classification of signals obtained through these spectroscopic techniques. LÄS MER

4. 23. Multiscale analysis of multi-channel signals

   Författare :Håkan Carlqvist; Jan-Olov Strömberg; Maria Hansson; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mathematical statistics; Matematisk statistik; Mathematical statistics; Matematisk statistik;

   Sammanfattning : I: Amplitude and phase relationship between alpha and beta oscillations in the human EEG We have studied the relation between two oscillatory patterns within EEG signals (oscillations with main frequency 10 Hz and 20 Hz), with wavelet-based methods. For better comparison, a variant of the continuous wavelet transform, was derived. LÄS MER

5. 24. Mild Traumatic Brain Injury : Studies on outcome and prognostic factors

   Författare :Marianne Lannsjö; Jörgen Borg; Per Enblad; Ulla Johansson; Richard Levi; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Rehabilitation; Mild Traumatic Brain Injury; Rivermead Post-concussion Symptoms Questionnaire; Rasch-analysis; prediction; outcome; head CT pathology; Magnet Resonance Imaging; Rehabilitation Medicine; Rehabiliteringsmedicin;

   Sammanfattning : Objectives: To explore the prevalence and structure of self-reported disability after mild traumatic brain injury and the impact of traumatic brain pathology on such outcome.Material and methods: In study 1-3, symptoms data were collected by use of Rivermead Post-concussion Symptoms Questionnaire (RPQ) and data on global function by use of Glasgow Outcome Scale Extended (GOSE) from 2602 patients at 3 months after MTBI. LÄS MER

7. 25. Modelling of Terahertz Planar Schottky Diodes

   Författare :Aik-Yean Tang; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; S-parameter extraction; Electro-thermal; Schottky diodes; Skin effect; Electromagnetic; Frequency multipliers; High-power frequency multiplier; Current crowding; Proximity effect; Submillimetre wave generation and detection; Geometric modelling; Gallium Arsenide;

   Sammanfattning : This thesis deals with the modelling of THz planar Schottky diodes, focusing on analyses of the geometry- dependent parasitics and the diode chip thermal management. Moving towards higher operating frequencies, the electromagnetic couplings pose significant limitations on the diode performance. LÄS MER