Search for dissertations about: "geometrical distortions"

Showing result 1 - 5 of 8 swedish dissertations containing the words geometrical distortions.

  2. 1. Geometric distortions in MRI based radiotherapy and PET/MRI

    Author : Josef Lundman; Tufve Nyholm; Anne Larsson; Jörgen Olofsson; Marco Riboldi; Umeå universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Magnetic resonance imaging; MRI; PET MR; PET MRI; medical imaging; radiotherapy; geometrical distortions; MR-only; MRI-only; radiofysik; radiation physics;

    Abstract : Magnetic resonance imaging (MRI) offers high soft-tissue contrast compared to computed tomography (CT). This contrast is helpful in many cases, not least for delineating tumours for radiotherapy treatment, and has led to increasing use in radiotherapy treatment planning (RTP). READ MORE

  4. 2. SAR Image Focus Errors due to Incorrect Geometrical Positioning in Fast Factorized Back-Projection

    Author : Annelie Wyholt; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Back-Projection; topography effects; range distortions; Autofocus; SAR;

    Abstract : Synthetic Aperture Radar, SAR, is an aperture synthesis technique to generate an image of the ground from air or space with high resolution. Signal processing is performed in frequency domain with Fourier Transform techniques, or in time domain with Back Projection techniques. READ MORE

  5. 3. Digital process planning of joining by numerical models in the automotive industry

    Author : Oscar Andersson; Arne Melander; KTH; []
    Keywords : Production Engineering; Industriell produktion;

    Abstract : The automotive industry is striving towards reduction of greenhouse gas emission by reducing product weight and improving fuel efficiency of their products. The introduction of lightweight materials have imposed greater pressure not only on the product development but also on manufacturing systems. READ MORE

  6. 4. Sintering simulation framework for 316L stainless steel components manufactured by binder jetting

    Author : Alberto Cabo Rios; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Sintering; sintering modelling; additive manufacturing; binder jetting; stainless steel.; dilatometry;

    Abstract : Binder Jetting (BJT) is an additive manufacturing (AM) technology allowing mass-production of small to medium-size metal components. BJT is a multi-step AM technology, where the geometrical shape of components is provided during the printing step, and the final properties are achieved through a second consolidation step - sintering. READ MORE

  7. 5. Nuclear Magnetic Resonance for Diffusion Imaging Development and evaluation of spin-echo-based pulse sequences for in vivo studies of water self-diffusion

    Author : Sara Brockstedt; Lund Medicinsk strålningsfysik; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; perfusion fraction; electrocardiographic triggering; segmented EPI SEPI ; echo-planar imaging EPI ; fast spin-echo FSE ; spin-echo SE ; navigator echoes; phase corrections; diffusion; Magnetic resonance; MRI; ischaemic stroke; Medicine human and vertebrates ; Medicin människa och djur ;

    Abstract : The interest in diffusion imaging with nuclear magnetic resonance techniques has increased during the last few years. The main reason is the possibility of early diagnosis of acute ischaemic stroke, at a time when conventional MR techniques and computerised tomography fail. READ MORE