Sökning: "non-stationary processes"

Visar resultat 1 - 5 av 19 avhandlingar innehållade orden non-stationary processes.

  1. 1. Estimation and Classification of Non-Stationary Processes : Applications in Time-Frequency Analysis

    Författare :Johan Brynolfsson; Statistical Signal Processing Group; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Time-Frequency Estimation; Parameter Estimation; Reassignment method; Non-Stationary Processes; Smooth spectral estimation; Neural Networks;

    Sammanfattning : This thesis deals with estimation and classification problems of non-stationary processes in a few special cases.In paper A and paper D we make strong assumptions about the observed signal, where a specific model is assumed and the parameters of the model are estimated. LÄS MER

  2. 2. Statistical inference and time-frequency estimation for non-stationary signal classification

    Författare :Rachele Anderson; Statistical Signal Processing Group; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Non-stationary processes; stochastic modeling; inference; spectral analysis; time-frequency analysis; classification; biomedical applications; deep learning;

    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

  3. 3. Predator responses to non-stationary rodent cycles

    Författare :Peter Hellström; Anders Angerbjörn; Xavier Lambin; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Buteo lagopus; Vulpes lagopus; Lemmus; Myodes; population cycles; predation; numerical response; functional response; arctic; lemmings; voles; fox; monitoring; raptors; zoologisk ekologi; Animal Ecology;

    Sammanfattning : Regular fluctuations in population size, cycles, are common in small mammals and have important effects on predator populations and life histories. In this thesis, I identify long-term patterns and processes in two specialist predators, the arctic fox Vulpes lagopus and the rough-legged buzzard Buteo lagopus, in relation to their prey (lemmings and voles) and in the case of the arctic fox also to a dominant competitor, the red fox Vulpes vulpes. LÄS MER

  4. 4. Noise diagnostics of Stationary and Non-Stationary Reactor Processes

    Författare :Carl Sunde; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; core-barrel vibrations; break-frequency method; wavelet; decay ratio; detector tube impacting; two-phase flow; spectral analysis; noise diagnostics;

    Sammanfattning : This thesis concerns the application of noise diagnostics on different problems in the area of reactor physics involving both stationary and non-stationary core processes. Five different problems are treated, divided into three different parts. LÄS MER

  5. 5. Numerical Modeling of Soot and NOx Formation in Non-Stationary Diesel Flames with Complex Chemistry

    Författare :Feng Tao; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; soot and NOx formation; non-stationary Diesel sprays; complex chemistry; Diesel spray auto-ignition; reaction zone structure; Diesel flame liftoff; turbulence-chemistry interaction;

    Sammanfattning : A complex chemistry model of reduced size (65 species and 268 reactions) derived on the basis of n-heptane auto-ignition kinetics, small hydrocarbon oxidation chemistry, polyaromatic hydrocarbon (PAH) and NOx formation kinetics together with a phenomenological soot model has been implemented in the KIVA code for multidimensional Diesel spray combustion simulations. An EDC (Eddy Dissipation Concept) based partially stirred reactor model is used to handle the turbulence-chemistry interaction. LÄS MER