Visar resultat 1 - 5 av 64 avhandlingar innehållade ordet Time-Frequency.
Sammanfattning : Non-stationary signals are very common in nature, e.g. sound waves such as human speech, bird song and music. It is usually meaningful to describe a signal in terms of time and frequency. LÄS MER
Sammanfattning : This thesis deals with ultrafast dynamics of electronic processes in rare gas atoms. The processes we explore include photoemission, where we time the emission of electrons moving away from the atomic core following ionization by a photon; and auto-ionization, where the atom spontaneously releases an electron wave-packet following photo-excitation. LÄS MER
Sammanfattning : The theory of stochastic time-frequency analysis of non-stationary random processes has mostly been developed for processes in continuous time. In practice however, random processes are observed, processed, and interpreted at a finite set of time points. LÄS MER
Sammanfattning : This licentiate thesis, containing two papers, is in the field of biomedical signal processing with main focus on signal processing of the ECG in patients with atrial fibrillation (AF). The two papers deal with different aspects of characterization of the f waves during atrial fibrillation. LÄS MER
Sammanfattning : This thesis focuses on statistical methods for non-stationary signals. The methods considered or developed address problems of stochastic modeling, inference, spectral analysis, time-frequency analysis, and deep learning for classification. LÄS MER