Search for dissertations about: "spectral fitting"

Showing result 1 - 5 of 32 swedish dissertations containing the words spectral fitting.

  1. 1. Spectral Analysis of Nonuniformly Sampled Data and Applications

    Author : Prabhu Babu; Peter Stoica; Fredrik Gustafsson; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Spectral analysis; array processing; nonuniform sampling; sparse parameter estimation; direction of arrival DOA estimation; covariance fitting; sinusoidal parameter estimation; maximum-likelihood; non-parametric approach; exoplanet detection; radial velocity technique; Sudoku; Electrical Engineering with specialization in Signal Processing; Elektroteknik med inriktning mot signalbehandling;

    Abstract : Signal acquisition, signal reconstruction and analysis of spectrum of the signal are the three most important steps in signal processing and they are found in almost all of the modern day hardware. In most of the signal processing hardware, the signal of interest is sampled at uniform intervals satisfying some conditions like Nyquist rate. READ MORE

  2. 2. Structural Elements in Native Celluloses

    Author : Kristina Wickholm; KTH; []
    Keywords : cellulose I; accessible fibril surfaces; inaccessible fibril surfaces; para-crystalline cellulose; fibril aggregates; CP MAS 13C-NMR spectroscopy; spectral fitting; PCA; PLS;

    Abstract : In this thesis, a schematic model for the structure ofaggregated cellulose I fibrils is proposed. The model consistsof a crystalline fibril core surrounded by less orderedcellulose forms. These cellulose forms are fibril surfacesaccessible to water, fibril surfaces inaccessible to water andpara-crystalline cellulose. READ MORE

  3. 3. Group-Sparse Regression : With Applications in Spectral Analysis and Audio Signal Processing

    Author : Ted Kronvall; Statistical Signal Processing Group; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sparse regression; group-sparsity; statistical modeling; regularization; hyperparameter-selection; spectral analysis; audio signal processing; classification; localization; multi-pitch estimation; chroma; convex optimization; ADMM; cyclic coordinate descent; proximal gradient;

    Abstract : This doctorate thesis focuses on sparse regression, a statistical modeling tool for selecting valuable predictors in underdetermined linear models. By imposing different constraints on the structure of the variable vector in the regression problem, one obtains estimates which have sparse supports, i.e. READ MORE

  4. 4. Material and technique development for ultrasound optical tomography using spectral hole burning filters

    Author : Alexander Bengtsson; NanoLund: Centre for Nanoscience; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Biomedical imaging; ultrasound optical tomography; acousto-optical tomography; rare-earth-ion doped crystals; spectral holeburning; slow light filters; Tm 3:LaF3; Fysicumarkivet A:2022:Bengtsson;

    Abstract : The molecular sensitivity provided by optical photons has potential advantages in medical diagnostics, for example, in distinguishing healthy from cancerous tissue. However, scattering resulting from inhomogeneities in the refractive index of tissues prevents spatially resolved optical measurements in biological material, except at very shallow depths. READ MORE

  5. 5. Model-based and matched-filterbank signal analysis

    Author : Andreas Jakobsson; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; non-parametric spectral estimation; efficient implementations; array processing; parameter estimation; identifiability; subspace fitting; Signal processing; Signalbehandling; Signal Processing; Signalbehandling;

    Abstract : The dissertation deals with model-based and matched-filterbank signal analysis. The matched-filterbank (MAFI) spectral estimation approach is introduced, and it is shown that both the amplitude spectrum Capon (ASC) and the amplitude and phase estimation (APES) spectral estimators can be expressed as MAFI spectral estimators. READ MORE