Search for dissertations about: "velocities"

Showing result 16 - 20 of 534 swedish dissertations containing the word velocities.

  2. 16. Simulation of dynamic instabilities during high rate deformation of ductile bars and plates

    Author : Kristina Nilsson; Mekanik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; numerical simulation; non-linear; wave propagation; multiple necking; necking; buckling; fracture; Mechanical engineering; Maskinteknik; finite elements; cohesive elements; dynamic; J2-flow theory; J2-deformation theory; viscoplastic; background inertia;

    Abstract : In this thesis, some of the phenomena occurring in plates and cylindrical bars subjected to dynamic loading are investigated. Numerical simulations using a dynamic finite element code are performed for a number of different sized specimens with various initial surface imperfections. Typically imposed loading velocities are in the range 10m/s.. READ MORE

  4. 17. Noninvasive assessment of cerebral circulation before, during and after carotid surgery

    Author : Helene Zachrisson; Göteborgs universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Internal carotid artery disease; cerebrovascular hemodynamics; Carotid thrombendarterectomy; Duplex ultrasound; transcranial Doppler; Internal carotid artery disease;

    Abstract : Non-invasive ultrasound investigations were evaluated in patients with carotid artery stenosis in comparison with radiological disease gradations and perioperative blood pressure measurements. The aim was to assess cerebrovascular hemodynamics before, during and after carotid thrombendarterectomy (CEA) in relation to the clinical outcome of the surgical intervention. READ MORE

  5. 18. Effects and nature on buffer ion enrichment in electric field assisted liquid chromatography

    Author : Björn Eriksson; []
    Keywords : ;

    Abstract : The aim of this study has been to investigate the properties and limitations of the separation technique electric field assisted capillary liquid chromatography (EF-LC). The electric current in the EF-LC has shown to be a limiting factor and has been the focus of the study. READ MORE

  6. 19. Coriolis generated secondary currents and their effects on turbulent channel flow

    Author : Rolf Larsson; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Vattenteknik; Water Resources Engineering;

    Abstract : The influence of secondary currents on various hydrodynamic processes in channel flow is discussed. Different mechanisms that generate secondary currents are presented. READ MORE

  7. 20. Influence of ice-cover on local scour at circular bridge piers : an experimental study

    Author : Peter Olsson; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Vattenteknik; Water Resources Engineering;

    Abstract : The objective of this work has been to investigate the effect of a simulated ice cover on the local scour depth around a cylindrical pier. Experiments were performed in a laboratory flume for different flow velocities with both a smooth and rough cover. The bed material consisted of uniform ripple-forming sand. READ MORE