Search for dissertations about: "WAVELET TRANSFORMS"

Found 5 swedish dissertations containing the words WAVELET TRANSFORMS.

  2. 1. Wavelet Analysis of Economic Time Series

    Author : Fredrik N G Andersson; Nationalekonomiska institutionen; []
    Keywords : SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; freight transportation activity; wavelet analysis; cointegration; inflation; bandspectrum regression; money; coreinflation;

    Abstract : Economic theory commonly distinguishes between different time horizons such as the short run and the long run. Models with many time horizons are easily studied in the frequency domain, because the various time horizons are associated with a particular frequency or band of frequencies. READ MORE

  4. 2. Wavelet theory and some of its applications

    Author : Elin Johansson; Luleå tekniska universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Mathematics; Matematik;

    Abstract : This thesis deals with applied mathematics with wavelets as a joint subject. There is an introduction and two extensive papers, of which one is already published in an international journal. READ MORE

  5. 3. Hilbert space frames and bases : a comparison of Gabor and wavelet frames and applications to multicarrier digital communications

    Author : Niklas Grip; Luleå tekniska universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Mathematics; Matematik;

    Abstract : Several signal processing applications today are based on the use of different transforms. The signals under consideration are written as a linear combination (or series) of some predefined set of functions. Traditionally, orthogonal bases have been used for this purpose, for example, in the discrete Fourier transform. READ MORE

  6. 4. Feature Extraction for Low-Frequency Signal Classification

    Author : José Chilo; Thomas Lindblad; Christian Bohm; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; infrasound; seismic signals; feature extraction; wavelets; fingerprints; mining; multimodal data space; Atomic physics; Atomfysik; Electronics;

    Abstract : The development of the International Monitoring System (IMS) for the verification of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) has led to a rapid revival of interest in infrasound. Furthermore, the installation of low-frequency sensors at seismic sites has increased in recent years, providing researchers with large and heterogeneous data-sets in near real-time. READ MORE

  7. 5. Features and Origin of Electromagnetic Fields Generated by Lightning Flashes

    Author : Mohd Muzafar Ismail; Vernon Cooray; Farhad Rachidi; Uppsala universitet; []
    Keywords : negative cloud-to-ground lightning flashes; HF and VHF radiation; chaotic pulse trains; lightning initiation; zero-crossing time; electromagnetic fields; Engineering Science with specialization in Atmospheric Discharges; Teknisk fysik med inriktning mot atmosfäriska urladdningar;

    Abstract : Negative cloud-to-ground (CG) lightning flashes transport negative charge from cloud to ground. Negative ground flashes typically involve various processes identified as preliminary breakdown, stepped leader, return stroke, dart leader, dart-stepped leader, subsequent return stroke, and cloud activity between strokes, such as regular pulse trains and chaotic pulse trains. READ MORE