Sökning: "line source model"

Visar resultat 1 - 5 av 128 avhandlingar innehållade orden line source model.

  1. 1. Model Based Speech Enhancement and Coding

    Författare :David Yuheng Zhao; Bastiaan Kleijn; Peter Kabal; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; statistical model; Gaussian mixture mdel GMM ; hidden Markov model HMM ; moise reduction; Telecommunication; Telekommunikation;

    Sammanfattning : In mobile speech communication, adverse conditions, such as noisy acoustic environments and unreliable network connections, may severely degrade the intelligibility and natural- ness of the received speech quality, and increase the listening effort. This thesis focuses on countermeasures based on statistical signal processing techniques. LÄS MER

  2. 2. Sparse Modeling of Grouped Line Spectra

    Författare :Ted Kronvall; Statistical Signal Processing Group; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; line spectra; parameter estimation; convex optimization; group-sparsity; block-sparsity; dictionary learning; ADMM; adaptive penalty; total variation; multi-pitch estimation; chroma; audio processing; TDOA; near-field localization; amplitude modulation;

    Sammanfattning : This licentiate thesis focuses on clustered parametric models for estimation of line spectra, when the spectral content of a signal source is assumed to exhibit some form of grouping. Different from previous parametric approaches, which generally require explicit knowledge of the model orders, this thesis exploits sparse modeling, where the orders are implicitly chosen. LÄS MER

  3. 3. Source Term Model Approaches to Film Cooling Simulations

    Författare :Petter Dahlander; Chalmers University of Technology; []
    Nyckelord :;

    Sammanfattning : Film cooling simulations using Computational Fluid Dynamics (CFD) are very difficult and extremely computer power demanding. This thesis deals with the development of a method to save computer power for these types of simulations. The cooling air is injected using additions to the source terms of the discretised governing equations. LÄS MER

  4. 4. Voltage Source Converters with Energy Storage Capability

    Författare :Hailian Xie; Hans-Peter Nee; Lennart Ängquist; Ambra Sannino; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Voltage source converter; StatCom; Energy storage; Active power compensation; Phase jump; Voltage dip; VSC; Weak network; Flux modulation; deadbeat control; Electric power engineering; Elkraftteknik;

    Sammanfattning : This project deals with voltage source converters with energy storage capability. The main objective is to study the possible benefits of energy storage to a power system with a VSC as the interface between them. First of all, a converter control system is proposed for a two level VSC. LÄS MER

  5. 5. A Signal Processing Approach to Practical Neurophysiology : A Search for Improved Methods in Clinical Routine and Research

    Författare :Björn Hammarberg; Dick Stegeman; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Systemteknik; matched filter; asynchronous detection; Kalman filter; initialization; MHT; Wiener deconvolution; line source model; electromyography; needle EMG; motor unit potential; MUAP; mean fiber concentration; jitter; microneurography; C-fiber; spike sorting; Systemteknik; Systems engineering; Systemteknik; Signal Processing; signalbehandling;

    Sammanfattning : Signal processing within the neurophysiological field is challenging and requires short processing time and reliable results. In this thesis, three main problems are considered.First, a modified line source model for simulation of muscle action potentials (APs) is presented. LÄS MER