Sökning: "term analysis"

Visar resultat 21 - 25 av 2534 avhandlingar innehållade orden term analysis.

  1. 21. Topics in polynomial sequences defined by linear recurrences

    Författare :INNOCENT NDIKUBWAYO; Boris Shapiro; Rikard Bøgvad; Tamás Forgács; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; recurrence relation; q-discriminant; generating function; polynomial sequence; support; real zeros; matematik; Mathematics;

    Sammanfattning : This licentiate consists of two papers treating polynomial sequences defined by linear recurrences.In paper I, we establish necessary and sufficient conditions for the reality of all the zeros in a polynomial sequence {P_i} generated by a three-term recurrence relation P_i(x)+ Q_1(x)P_{i-1}(x) +Q_2(x) P_{i-2}(x)=0 with the standard initial conditions P_{0}(x)=1, P_{-1}(x)=0, where Q_1(x) and Q_2(x) are arbitrary real polynomials. LÄS MER

  3. 22. High order summation-by-parts based approximations for discontinuous and nonlinear problems

    Författare :Cristina La Cognata; Jan Nordström; Sara Zahedi; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Numerical approximations using high order finite differences on summation-byparts (SBP) form are investigated for discontinuous and fully nonlinear systems of partial differential equations. Stability and conservation properties of the approximations are obtained through a weak imposition of interface and boundary conditions with the simultaneous-approximation-term (SAT) technique. LÄS MER

  4. 23. On pressure-driven Hele-Shaw flow

    Författare :Salvador Manjate; Peter Wall; John Fabricius; Johan Byström; Niklas Lundström; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Applied Mathematics; Tillämpad matematik;

    Sammanfattning : The present licentiate thesis is devoted to the rigorous derivation of the equations governing thin-film flow of incompressible Newtonian and non-Newtonian fluids. More precisely, we consider flow in a generalized Hele-Shaw cell, which is a thin three-dimensional domain confined between two surfaces connected by cylindrical obstacles of various shapes. LÄS MER

  5. 24. Integral representations of Herglotz-Nevanlinna functions

    Författare :Mitja Nedic; Annemarie Luger; Alexandru Aleman; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; integral representations; Herglotz-Nevanlinna functions; several complex variables; Mathematics; matematik;

    Sammanfattning : In this thesis, we study integral representations of Herglotz-Nevanlinna functions, that is to say holomorphic functions defined on a product of several copies of the complex upper half-plane having non-negative imaginary part. The manuscript is divided into three parts, beginning with a general introduction followed by two papers. LÄS MER

  7. 25. Bifurcations and Exchange of Stability with Density Dependence in a Coinfection Model and an Age-structured Population Model

    Författare :Jonathan Andersson; Vladimir Kozlov; Uno Wennergren; Ezio Venturino; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : In nature many pathogens and in particular strains of pathogens with negative effects on species coexists. This is for simplicity often ignored in many epidemiological models. It is however still of interest to get a deeper understanding how this coexistence affects the dynamics of the disease. LÄS MER