Sökning: "M Hellgren"

Hittade 4 avhandlingar innehållade orden M Hellgren.

  1. 1. G-structures and Families of Isotropic Submanifolds in Complex Contact Manifolds

    Författare :Patrik Hellgren; Sergei Merkulov; Henrik Pedersen; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Differential geometry; twistor; G-structures; deformation; MATHEMATICS; MATEMATIK; matematik; Mathematics;

    Sammanfattning : We study a generalized twistor correspondence between irreducible G-structures (with torsion in general) on complex manifolds Z and moduli spaces M of deformations of isotropic homogeneous submanifolds X in complex contact manifolds Y.For any irreducible G-structure on a complex manifold M we present an explicit construction of a contact manifold (a generalized twistor space) Y with contact line bundle L and a family F of isotropic submanifolds X in Y having M as its moduli space. LÄS MER

  3. 2. A systems approach to ice loads on concrete dams

    Författare :Rikard Hellgren; Richard Malm; Anders Ansell; Erik Nordström; Pierre Legér; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ice loads; Ice pressure; Dam safety; Concrete dams; Cold regions; Monitoring; Measurements; Concrete Structures; Betongbyggnad;

    Sammanfattning : Dams are mainly used for the storage of water to electricity production and irrigation, or for river regulation. Continuous work to assure a high dam safety level is a prerequisite to minimize the risk for the uncontrolled release of water. LÄS MER

  4. 3. Characterisation of inputs and outputs of striatal medium spiny neurons in health and disease

    Författare :Marko Filipović; Jeanette Hellgren Kotaleski; Arvind Kumar; Gilad Silberberg; Ad Aertsen; Andrew Sharott; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; basal ganglia; striatum; medium spiny neurons; subthalamic nucleus; globus pallidus; Parkinson s disease; in vivo; oscillations; spectral analysis; response variability; networks; simulations; modelling; Numerical Analysis; Numerisk analys; Computer Science; Datalogi; Biological and Biomedical Physics; Biologisk och biomedicinsk fysik;

    Sammanfattning : Striatal medium spiny neurons (MSNs) play a crucial role in various motor and cognitive functions. They are separated into those belonging to the direct pathway (dMSNs) and the indirect pathway (iMSNs) of the basal ganglia, depending on whether they express D1 or D2 type dopamine receptors, respectively. LÄS MER

  5. 4. Synthesis and characterization of magnetic nanolaminated carbides

    Författare :Andrejs Petruhins; Johanna Rosén; Per O. Å. Persson; Niklas K. Hellgren; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : MAX phases are a group of nanolaminated ternary carbides and nitrides, with a composition expressed by the general formula Mn+1AXn (? = 1 − 3), where M is a transition metal, A is an A-group element, and X is carbon and/or nitrogen. MAX phases have attracted interest due to their unique combination of metallic and ceramic properties, related to their inherently laminated structure of a transition metal carbide (Mn+1Xn) layer interleaved by an A-group metal layer. LÄS MER