Sökning: "Peter Lundberg"

Visar resultat 21 - 25 av 36 avhandlingar innehållade orden Peter Lundberg.

  1. 21. Characterization of the MRI patient exposure environment and exposure assessment methods for magnetic fields in MRI scanners

    Författare :Jennifer Frankel; Jonna Wilén; Anders Garpebring; Johan Olsrud; Peter Lundberg; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; electromagnetic fields; exposure assessment; magnetic resonance imaging; switched gradient fields; radiofrequency fields; exposure metrics; radiofysik; radiation physics;

    Sammanfattning : Magnetic resonance imaging (MRI) has become one of the most common imaging modalities available in modern medicine, and it is an indispensable diagnostic tool thanks to the unparalleled soft-tissue contrast and high image resolution. It is also a unique exposure environment consisting of a complex mix of magnetic fields. LÄS MER

  3. 22. On atmospheric low frequency variability, teleconnections and link to jet variability

    Författare :Waheed Iqbal (وحید اقبال ); Abdel Hannachi; Peter Lundberg; Thomas Spengler; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; atmosfärvetenskap och oceanografi; Atmospheric Sciences and Oceanography;

    Sammanfattning : The atmosphere is a complex system with an infinite number of independent variables. The best approximations of the atmosphere are made using numerical models. The use of such models provides an invaluable tool for studying the atmospheric system. LÄS MER

  4. 23. Piezoelectric Generation and Damping of Extensional Waves in Bars

    Författare :Anders Jansson; Bengt Lundberg; Urmas Valdek; Peter Olsson; Uppsala universitet; []
    Nyckelord :Technology; Piezoelectric; wave; generation; damping; bar; TEKNIKVETENSKAP;

    Sammanfattning : This thesis focuses on the electromechanical processes of generation and damping of transient waves in bars with attached piezoelectric members. In particular, the influence of amplifier and electrical circuitry on the mechanical waves is of interest. LÄS MER

  5. 24. Some Concepts of Estuarine Modeling

    Författare :Bror Jönsson; Peter Lundberg; Kristofer Döös; Björn Kjärfve; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Oceanography Modeling Estuaries; Meteorology; Meteorologi;

    Sammanfattning : If an estuarine system is to be investigated using an oceanographic modeling approach, a decision must be made whether to use a simple and robust framework based on e.g. mass-balance considerations, or if a more advanced process-resolving three-dimensional (3-D) numerical model are necessary. LÄS MER

  7. 25. Social Entrepreneurship and Influence on Regional Firm Demography

    Författare :Habib M. Kachlami; Martin Johanson; Peter Öhman; Heléne Lundberg; Mats Westerberg; Mittuniversitetet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES;

    Sammanfattning : The central interest of this thesis is the emergence of social  ventures. In this regard, it investigates two types of questions: what regional factors influence the emergence of social  ventures? and what  types of interaction may emerge between the emergence of social  ventures and the demography (entry,  exit  and migration) of commercial ventures in a region? The thesis also aims to adopt a macro-oriented approach to studying the research questions. LÄS MER