Sökning: "strong invariants"

Visar resultat 1 - 5 av 18 avhandlingar innehållade orden strong invariants.

  1. 1. Nonlinear Theory of Partially Coherent Optical Waves

    Författare :Tobias Hansson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nonlinear optics; partial coherence; beam collapse; saturable logarithmic media; soliton interaction; dressing method; parabolic beams; Wigner transform; invariants; modulational instability;

    Sammanfattning : Nonlinear effects arise in optics as a consequence of the medium properties being modified by the presence of light. Of particular interest are situations where the effect of the nonlinearity can be described by an intensity dependent refractive index and the subsequent interplay with dispersion and diffraction. LÄS MER

  3. 2. Functional Program Correctness Through Types

    Författare :Nils Anders Danielsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; well-typed syntax; normalisation by evaluation; program correctness; total languages; partial languages; lazy evaluation; time complexity; strong invariants; dependent types;

    Sammanfattning : This thesis addresses the problem of avoiding errors in functionalprograms. The thesis has three parts, discussing different aspects ofprogram correctness, with the unifying theme that types are anintegral part of the methods used to establish correctness. LÄS MER

  4. 3. Construction of Adaptive Multistep Methods for Problems with Discontinuities, Invariants, and Constraints

    Författare :Fatemeh Mohammadi; Numerisk analys; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; multistep methods; Initialization; beta-blocking; Discontinuity; Time adaptivity; Strong stability preserving; Differential algebraic equations;

    Sammanfattning : Adaptive multistep methods have been widely used to solve initial value problems. These ordinary differential equations (ODEs) may arise from semi-discretization of time-dependent partial differential equations(PDEs) or may combine with some algebraic equations to represent a differential algebraic equations (DAEs). LÄS MER

  5. 4. MHD Stability and Confinement of Plasmas in a Single Mirror Cell

    Författare :Natalia Savenko; Olov Ågren; Per Helander; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Engineering physics; MHD; plasma confinement; magnetic mirror; adiabatic particle motion; adiabatic invariants; Teknisk fysik; Engineering physics; Teknisk fysik;

    Sammanfattning : Thermonuclear fusion is a promising energy source for the future. If an economically efficient thermonuclear reactor would be built it has to be a cheap, safe, and highly productive electric power plant, or, a heating plant. LÄS MER

  7. 5. Multipoint Okounkov bodies, strong topology of ω-plurisubharmonic functions and Kähler-Einstein metrics with prescribed singularities

    Författare :Antonio Trusiani; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Okounkov bodies; Seshadri constant; Kähler-Einstein metrics; Kähler Geometry; Canonical metrics; Fano manifolds; Pluripotential theory; Complex Monge-Ampère equations; Kähler packing;

    Sammanfattning : The most classical topic in Kähler Geometry is the study of Kähler-Einstein metrics as solution of complex Monge-Ampère equations. This thesis principally regards the investigation of a strong topology for ω-plurisubharmonic functions on a fixed compact Kähler manifold (X,ω), its connection with complex Monge-Ampère equations with prescribed singularities and the consequent study of singular Kähler-Einstein metrics. LÄS MER