Sökning: "tensor"

Visar resultat 11 - 15 av 266 avhandlingar innehållade ordet tensor.

  1. 11. Diffusion tensor magnetic resonance imaging of the brain : Tractography analysis with application in healthy individuals and patients

    Författare :Johanna Mårtensson; Elna-Marie Larsson; Jimmy Lätt; Danielle van Westen; Tim Dyrby; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Magnetic Resonance Imaging; Diffusion Tensor Imaging; Tractography; white matter tracts; Radiology; Radiologi;

    Sammanfattning : In study 1, thirty-eight healthy controls were used for optimization of the method. Fifteen patients with progressive supranuclear palsy and an equal number of age-matched healthy controls underwent diffusion tensor MRI and were then investigated and compared groupwise. LÄS MER

  3. 12. Theoretical and computational advances in small-angle x-ray scattering tensor tomography

    Författare :Leonard Nielsen; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; tensor tomography; reciprocal space map; small-angle scattering;

    Sammanfattning : The relationships between microscopic and macroscopic structures is a central topic of materials physics. Small-angle x-ray scattering (SAXS) is a powerful experimental technique for probing and mapping variations in electron density, given by the reciprocal space map, down to the nanometer scale in two dimensions. LÄS MER

  4. 13. The Chevreton tensor and its trace

    Författare :Ingemar Eriksson; Marc Mars; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; MATHEMATICS; MATEMATIK;

    Sammanfattning : In this thesis we investigate the Chevreton tensor in Einstein-Maxwell theory. It was introduced in 1964 as the counterpart, for electromagnetic fields, of the well-known Bel-Robinson tensor of the gravitational field. We prove that, in the absence of electromagnetic sources, this tensor is completely symmetric. LÄS MER

  5. 14. Applications of diffusion MRI: Tensor-valued encoding, time-dependent diffusion, and histological validation

    Författare :Jan Brabec; Lund Medicinsk strålningsfysik; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; diffusion MRI; meningioma; glioma; brain tumors; intracranial tumors; undulations; restricted diffusion; time dependence; spherical b-tensor encoding; linear b-tensor encoding; histogram analysis; anisotropic kurtosis; isotropic kurtosis; hyperintensity; conspicuity; white matter; detection; diffusion spectrum; consistency; type; grade; axon diameter; axonal trajectories; Fysicumarkivet A:2022:Brabec;

    Sammanfattning : Diffusion MRI (dMRI) sensitizes the MR signal to the diffusion of water molecules at the microscopic level and thereby non-invasively probes tissue microstructure. This is relevant when determining biological properties of tissues, for example, cancer type and its malignancy. LÄS MER

  7. 15. Diffusion Tensor Imaging and Tractography in Epilepsy Surgery Candidates

    Författare :Daniel Nilsson; Göteborgs universitet; []
    Nyckelord :epilepsy; epilepsy surgery; temporal lobe resection; optic radiation; diffusion tensor imaging; tractography;

    Sammanfattning : In selected patients with medically refractory epilepsy, surgical treatment can render the patients seizure free or significantly reduce seizure frequency. Temporal lobe resection (TLR) for temporal lobe epilepsy (TLE) is the most commonly performed epilepsy surgery procedure. LÄS MER