Sökning: "non-stationary random processes"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden non-stationary random processes.

1. 1. Ambiguity Domain Definitions and Covariance Function Estimation for Non-Stationary Random Processes in Discrete Time

   Författare :Johan Sandberg; Matematisk statistik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : The ambiguity domain plays a central role in estimating the time-varying spectrum of a non-stationary random process in continuous time, since multiplication in this domain is equivalent with estimating the covariance function of the random process using an intuitively appealing estimator. For processes in discrete time there exists a corresponding covariance function estimator. LÄS MER

3. 2. Discrete Stochastic Time-Frequency Analysis and Cepstrum Estimation

   Författare :Johan Sandberg; Matematisk statistik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; ambiguity domain; time-frequency analysis; time-frequency representations; covariance function; non-stationary random processes; Speaker recognition; MFCC; cepstrum;

   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

4. 3. Crossings and maxima in Gaussian fields and seas

   Författare :Eva Sjö; Matematisk statistik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; operations research; Statistics; random waves; extremes; generalised Rice s formula; level-crossings; Gaussian random fields; programming; actuarial mathematics; Statistik; operationsanalys; programmering; aktuariematematik;

   Sammanfattning : In this thesis the focus is on crossing points in random fields and the probability distributions of various crossing variables in different applications. The crossing points are generalisations to random fields of points of level crossings by stochastic processes. LÄS MER

5. 4. Radio Channel Prediction Based on Parametric Modeling

   Författare :Ming Chen; Chalmers University of Technology; []
   Nyckelord :Wireless communications; channel prediction; GLRT; CRLB; NLLS; polynomial phase signal; Kalman filter; NILS.; sinusoidal modeling; channel modeling; MIMO;

   Sammanfattning : Long range channel prediction is a crucial technology for future wireless communications. The prediction of Rayleigh fading channels is studied in the frame of parametric modeling in this thesis.Suggested by the Jakes model for Rayleigh fading channels,deterministic sinusoidal models were adopted for long rangechannel prediction in early works. LÄS MER

7. 5. Stochastic modelling and analysis of early mouse development

   Författare :Sofia Tapani; Göteborgs universitet; Göteborgs universitet; Gothenburg University; Göteborgs universitet; Gothenburg University; []
   Nyckelord :NATURVETENSKAP; MEDICIN OCH HÄLSOVETENSKAP; NATURAL SCIENCES; MEDICAL AND HEALTH SCIENCES; correlation; CUSUM; mouse; non-stationarity; pronucleus; stochastic differential equation; time series; wavelet decomposition; yeast; CUSUM;

   Sammanfattning : The aim of this thesis is to model and describe dynamical events for biological cells using statistical and mathematical tools. The thesis includes five papers that all relate to stochastic modelling of cells. LÄS MER