Sökning: "interval analysis"

Visar resultat 1 - 5 av 373 avhandlingar innehållade orden interval analysis.

  1. 1. Spectral analysis of the heart rate variability : a methodological study

    Författare :Urban Niklasson; Umeå universitet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; Heart-rate variability; R-R interval; cardiac autonomic function; spectral analysis; IPFM model;

    Sammanfattning : Heart rate and other cardiovascular variables are not steady but fluctuate over time. The evolution of computer technology the last 2 decades has made detailed analysis of the fluctuations possible and has focused the attention to the information content of the variability. LÄS MER

  2. 2. Computational dynamics – real and complex

    Författare :Anna Belova; Warwick Tucker; Denis Gaidashev; Àlex Haro Provinciale; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; Continued fractions; Generating functions; Rotation numbers; Rigorous computations; Interval analysis; Interval arithmetic; Multipliers; Quadratic map; Kuramoto-Sivashinsky equation; Mathematics; Matematik;

    Sammanfattning : The PhD thesis considers four topics in dynamical systems and is based on one paper and three manuscripts.In Paper I we apply methods of interval analysis in order to compute the rigorous enclosure of rotation number. LÄS MER

  3. 3. Weighted inequalities involving Hardy-type and limiting geometric mean operators

    Författare :Maria Nassyrova; Luleå tekniska universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Mathematics; Matematik;

    Sammanfattning : This thesis consists of an introduction and five papers, which all are devoted to different questions connected to weighted Hardy-type inequalities and their generalizations. The introduction gives an elementary overview of the area and serves as a frame for the following papers. In particular, it is pointed out where the obtained results fit in. LÄS MER

  4. 4. Qualitative and Spectral theory of some regular non-definite Sturm-Liouville problems

    Författare :Mervis Kikonko; Luleå tekniska universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Matematik; Mathematics;

    Sammanfattning : In this Licentiate thesis, we study some regular non-definite Sturm-Liouville problems. In this case, the weight function takes on both positive and negative signs on a given interval [a, b]. One feature of the non-definite Sturm-Liouville problem is the possible existence of non-real eigenvalues, unlike in the definite case (i.e. LÄS MER

  5. 5. Some new results concerning general weighted regular Sturm-Liouville problems

    Författare :Mervis Kikonko; Lars-Erik Persson; Peter Wall; Angelo B. Mingarelli; Alexey Karapetyants; Luleå tekniska universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Partial differential equations; Sturm-Liouville problem; Right-definite; left-definite; non-definite; indefinite; Dirichlet problem; spectrum; eigenvalues; non-real eigenvalues; Richardson number; Richardson index; turning point; Mathematics; Matematik;

    Sammanfattning : In this PhD thesis we study some weighted regular Sturm-Liouville problems in which the weight function takes on both positive and negative signs in an appropriate interval [a,b]. With such  problems there is the possible existence of non-real eigenvalues, unlike in the definite case (i.e. LÄS MER