Search for dissertations about: "spurious"

Showing result 1 - 5 of 84 swedish dissertations containing the word spurious.

  2. 1. Susceptibility effects in MRI and 1H MRS. The spurious echo artifact and susceptibility measurements

    Author : Åsa Carlsson; Göteborgs universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MRI; 1H MRS; susceptibility; spurious echo; artifact; artefact;

    Abstract : When performing magnetic resonance (MR) experiments, a strong homogeneous magnetic field is often preferred, especially in clinical applications. However, all objects that are placed in the magnetic field will disturb the field homogeneity and cause local magnetic field gradients. READ MORE

  4. 2. The Dirac Equation: Numerical and Asymptotic Analysis

    Author : Hasan Almanasreh; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Dirac operator; eigenvalue problem; finite element method; spurious eigenvalues; Petrov-Galerkin; cubic Hermite basis functions; stability parameter; meshfree method; $hp$-cloud; intrinsic enrichment; G-convergence; $ Gamma$-convergence; scattering theory; identification; wave operator; stationary approach; Dirac operator;

    Abstract : The thesis consists of three parts, although each part belongs to a specific subject area in mathematics, they are considered as subfields of the perturbation theory. The main objective of the presented work is the study of the Dirac operator; the first part concerns the treatment of the spurious eigenvalues in the computation of the discrete spectrum. READ MORE

  5. 3. Congenital clubfoot : Aspects on epidemiology, residual deformity and patient reported outcome

    Author : Henrik M Wallander; Göran Hansson; Sune Larsson; Michael Benson; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Congenital clubfoot; incidence; ultrasonography; forefoot adduction; navicular position; spurious correction; Ilizarov External Fixator; subjective outcome; stiffness; patient reported outcome; norm group; gender difference; Orthopaedics; Ortopedi; Orthopaedics; ortopedi;

    Abstract : The overall aim of this thesis on congenital clubfoot was to estimate the incidence with a national perspective, analyse residual deformities and their management, and evaluate patient reported long-term quality of life and foot function. Paper I was a prospective, nationwide sampling of 280 children with congenital clubfoot during 1995-96. READ MORE

  6. 4. Reliable hp finite element computations of scattering resonances in nano optics

    Author : Juan Carlos Araujo-Cabarcas; Christian Engström; David Cohen; Mats G. Larson; Jeffrey Ovall; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Scattering resonances; Helmholtz problems; pseudospectrum; Lippmann-Schwinger equation; finite element methods; nonlinear eigenvalue problems; spurious solutions;

    Abstract : Eigenfrequencies are commonly studied in wave propagation problems, as they are important in the analysis of closed cavities such as a microwave oven. For open systems, energy leaks into infinity and therefore scattering resonances are used instead of eigenfrequencies. READ MORE

  7. 5. Generation, Modulation, and Detection of Signals in Microwave Photonic Systems

    Author : Andreas Wiberg; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Microwave photonics; radio over fiber; mm-wave generation; PSK; QAM; subcarrier modulation; photonic frequency multiplication; spurious free dynamic range third-order intercept point; millimeter-wave photonics; uni-travelling-carrier photodiode; millimeter-wave communication system;

    Abstract : This thesis deals with the use of photonic technology in microwave and millimeter-wave applications. The two major parts of this work have been techniques for transmission and signal generation. READ MORE