Sökning: "spectral reduction"

Visar resultat 1 - 5 av 86 avhandlingar innehållade orden spectral reduction.

1. 1. Advanced Spectral Analysis with Applications

   Författare :Niclas Sandgren; Peter Stoica; Thomas L. Marzetta; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; frequency-selective spectral analysis; damped sinusoidal model; prior knowledge; multichannel spectroscopy; phantom experimental data; in-vivo in-vitro data analysis; area-selective analysis; cepstrum thresholding; total-variance reduction; two-dimensional spectral estimation; spectral smoothing; irregular sampling; CARMA signals; Signal processing; Signalbehandling;

   Sammanfattning : Spectral analysis has advanced the last decades as a signal processing tool to extract significant information about certain properties of measured data. The practical use of spectral analysis techniques in time-series analysis has been emphasized in the immense amount of previous literature in the field and by a rapidly growing number of applications. LÄS MER

3. 2. Spectral Moment Problems : Generalizations, Implementation and Tuning

   Författare :Enrico Avventi; Anders Lindquist; Giorgio Picci; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Optimization; systems theory; Optimeringslära; systemteori;

   Sammanfattning : Spectral moment interpolation find application in a wide array of use cases: robust control, system identification, model reduction to name the most notable ones. This thesis aims to expand the theory of such methods in three different directions. The first main contribution concerns the practical applicability. LÄS MER

4. 3. Modeling and Model Reduction by Analytic Interpolation and Optimization

   Författare :Giovanna Fanizza; Anders Lindquist; György Michaletzky; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Analytic Interpolation theory with a degree constraint; rational covariance extension problem; spectral estimation; model reduction; optimization; passive system; Optimization; systems theory; Optimeringslära; systemteori;

   Sammanfattning : This thesis consists of six papers. The main topic of all these papers is modeling a class of linear time-invariant systems. The system class is parameterized in the context of interpolation theory with a degree constraint. LÄS MER

5. 4. Inverse Problems in Analytic Interpolation for Robust Control and Spectral Estimation

   Författare :Johan Karlsson; Anders Lindquist; Alberto Isidori; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nevanlinna-Pick Interpolation; Approximation; Model Reduction; Robust Control; Gap-robustness; Sensitivity Shaping; Entropy functional; Spectral Estimation; Weak*-topology; Monge-Kantorovic Transportation; Optimization; systems theory; Optimeringslära; systemteori;

   Sammanfattning : This thesis is divided into two parts. The first part deals with theNevanlinna-Pick interpolation problem, a problem which occursnaturally in several applications such as robust control, signalprocessing and circuit theory. We consider the problem of shaping andapproximating solutions to the Nevanlinna-Pick problem in a systematicway. LÄS MER

7. 5. Nonlinear dimensionality reduction of gene expression data

   Författare :Jens Nilsson; Matematik LTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Gene expression; Manifold learning; Nonlinear dimensionality reduction; Microarray;

   Sammanfattning : Using microarray measurements techniques, it is possible to measure the activity of genes simultaneously across the whole genome. Since genes influence each others activity levels through complex regulatory networks, such gene expression measurements are state samples of a dynamical system. LÄS MER