Search for dissertations about: "steepest-descent algorithms"

Found 2 swedish dissertations containing the words steepest-descent algorithms.

  2. 1. System Modeling Using Basis Functions and Application to Echo Cancelation

    Author : Lester S.H. Ngia; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Laguerre filters; Gauss-Newton algorithms; Levenberg-Marquard algorithms; room acoustics; separable nonlinear least-squares; adaptive filtering; off-line estimation; echo cancelation; on-line estimation; system modeling; neural net filters; Kautz filters; loudspeaker systems; steepest-descent algorithms; Hammerstein models;

    Abstract : This thesis concerns modeling of linear and nonlinear dynamic systems, where the applied models can be described by basis function expansions. In the first part of the thesis, the investigated model (or filter) structures and parameter estimation algorithms are described. READ MORE

  4. 2. Online power transformer diagnostics using multiple modes of microwave radiation

    Author : Mariana Dalarsson; Martin Norgren; Sven Nordebo; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; inverse problem; multiple modes; power transformers;

    Abstract : In the present thesis, we propose and investigate a new approach to diagnose the effects of the various degradation mechanisms, including thermal degradation at hot spots, winding deformations due to the mechanical forces from short circuit currents, partial discharges due to local electric field surges, and increased moisture levels in the cellulose insulation due to decomposition, that affect electric power transformers during their normal operation in an electric power grid.Although the proposed diagnostics method can in principle be used to detect various degradation mechanisms mentioned above, we focus in the present thesis on mechanical deformations of transformer winding structures. READ MORE