Essays about: "Wiener"

Showing result 1 - 5 of 79 essays containing the word Wiener.

  1. 1. A geometric approach to calculating the limit set of eigenvalues for banded Toeplitz matrices

    University essay from Lunds universitet/Matematik LTH

    Author : Teodor Bucht; [2023]
    Keywords : Toeplitz matrices; Banded Toeplitz matrices; Limit set; Eigenvalues; Mathematics and Statistics;

    Abstract : This thesis is about the limiting eigenvalue distribution of n × n Toeplitz matrices as n → ∞. The two classical questions we want to answer are: what is the limit set of the eigenvalues, and what is the limiting distribution of the eigenvalues. Our main result is a new approach to calculate the limit set Λ(b) for a Laurent polynomial b, i.e. READ MORE

  3. 2. The effects of management practices and environmental variables on the biodiversity of Nardus grasslands in the national park Hohe Tauern, Austria

    University essay from SLU/Dept. of Ecology

    Author : Rebecca Paulina Dörner; [2023]
    Keywords : biodiversity; Nardus stricta; Nardus grassland; national park Hohe Tauern; East Tyrol; alpine pastures;

    Abstract : Introduction. A large part of the biodiversity of the Alps is linked to an interaction between the natural environment and traditional land-use practices. This study focuses on the priority habitat type of species rich Nardus grasslands (Natura 2000 Code 6230*), which is endangered, but continues to thrive in extensively managed subalpine pastures. READ MORE

  4. 3. Contribution to the Understanding of the Effects of Propagation through the Ionosphere of P-band SAR Data

    University essay from Luleå tekniska universitet/Institutionen för system- och rymdteknik

    Author : Johannes Samuel Erland Rönner; [2023]
    Keywords : Synthetic aperture radar; Ionosphere;

    Abstract : The BIOMASS mission from the European Space Agency (ESA) is designed to measurebiomass and carbon content in Earth’s forests. To account for phase changes caused byionospheric variations, a map-drift autofocus algorithm is developed, which utilises a phasescreen of the ionosphere to eliminate phase errors in the signal. READ MORE

  5. 4. Speckle suppression in ultrasound images of heterogeneous materials

    University essay from Luleå tekniska universitet/Institutionen för system- och rymdteknik

    Author : Simon Johnsson; [2023]
    Keywords : Ultrasound; non-destructive testing; wiener filter; signal processing;

    Abstract : Performing non-destructive testing (NDT) on materials is a helpful tool for maintenance and quality control because the materials are not destroyed or disturbed; ultrasound imaging is one type of NDT. Ultrasound imaging of heterogeneous materials contains many echoes from the material itself. READ MORE

  6. 5. Evaluation of a Novel Reconstruction Framework for Gamma Knife Cone-Beam CT - The Impact of Scatter Correction and Noise Filtering on Image Quality and Co-registration Accuracy

    University essay from KTH/Fysik

    Author : Ida Hägnestrand; [2023]
    Keywords : Gamma Knife; Cone-beam computed tomography; Image quality; Image reconstruction; Co-registration; Contrast; Uniformity; Spatial resolution; Scatter correction; Wiener filter; Noise filter; Patient positioning; Stereotactic radiosurgery; Gammakniv; Strålkniv; Cone-Beam Computed Tomography; Bildkvalitet; Bildrekonstruktion; Co-registrering; Kontrast; Uniformitet; Spatial upplösning; Spridningskorrigering; Wienerfilter; Brusfilter; Stereotaktisk strålkirurgi;

    Abstract : The Gamma Knife is a non-invasive stereotactic radiosurgery system used for treatments of deep targets in the brain. Accurate patient positioning is needed for precise radiation delivery to the target. READ MORE