Sökning: "rotating magnetic field"

Visar resultat 26 - 30 av 31 avhandlingar innehållade orden rotating magnetic field.

  1. 26. CO studies of Herbig-Haro regions

    Författare :René Liseau; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : High resolution CO (J=1-0) observations of HH 7-11 in NGC 123? and the region around Lk Ha 224 in NGC 7129, using the 25m Millimeter Wave Telescope at Onsala, Sweden, have resulted in detailed maps. These dark cloud regions, forming stars of low to intermediate mass, show signs of shock excitation, identified as Herbig-Haro objects and H?0 masers. LÄS MER

  3. 27. Modelling and analysis of multiphysical interactions in hydropower rotor systems

    Författare :Martin Karlsson; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Datorstödd maskinkonstruktion; Computer Aided Design;

    Sammanfattning : In this thesis the objective is to develop rotordynamical models of hydropower units, where coupling between mechanical, electromagnetic and fluid dynamical system systems is of certain interest. Both fluid-rotor and electromechanical interactions are known to change the system coefficients of the rotor system, which affects eigenfrequencies, damping, stability and response. LÄS MER

  4. 28. NMR studies of Carbohydrate Structure and Dynamics in Solution

    Författare :Torgny Rundlöf; Thomas Peters; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organic Chemistry; organisk kemi;

    Sammanfattning : Methods for studies of the structures of carbohydrates in solution and their dynamics are presented. Approaches employing nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry (MS), force-field computer simulations and chemical methods are described. LÄS MER

  5. 29. High-Performance Finite Element Methods : with Application to Simulation of Diffusion MRI and Vertical Axis Wind Turbines

    Författare :Van-Dang Nguyen; Johan Hoffman; Johan Jansson; Axel Målqvist; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; High performance finite element method; computational diffusion MRI; turbulent flow; vertical axis wind turbine.; Computer Science; Datalogi;

    Sammanfattning : The finite element methods (FEM) have been developed over decades, and together with the growth of computer engineering, they become more and more important in solving large-scale problems in science and industry. The objective of this thesis is to develop high-performance finite element methods (HP-FEM), with two main applications in mind: computational diffusion magnetic resonance imaging (MRI), and simulation of the turbulent flow past a vertical axis wind turbine (VAWT). LÄS MER

  7. 30. Digital motion control techniques for electrical drives

    Författare :Sanath Alahakoon; KTH; []
    Nyckelord :;

    Sammanfattning : Digital motion control area toady is a well-established one,which is believed to be first initiated by power electronicengineers in the early seventies. Modern digital controltheory, advances in digital signal processor andmicrocontroller technology and recent developments in powerelectronic devices have made this field a very competitive one. LÄS MER