Sökning: "Matematisk logik"
Visar resultat 6 - 10 av 26 avhandlingar innehållade orden Matematisk logik.
6. Admissible transformations and the group classification of Schrödinger equations
Sammanfattning : We study admissible transformations and solve group classification problems for various classes of linear and nonlinear Schrödinger equations with an arbitrary number n of space variables.The aim of the thesis is twofold. LÄS MER
7. Generalized Vandermonde matrices and determinants in electromagnetic compatibility
Sammanfattning : Matrices whose rows (or columns) consists of monomials of sequential powers are called Vandermonde matrices and can be used to describe several useful concepts and have properties that can be helpful for solving many kinds of problems. In this thesis we will discuss this matrix and some of its properties as well as a generalization of it and how it can be applied to curve fitting discharge current for the purpose of ensuring electromagnetic compatibility. LÄS MER
8. Reordering in Noncommutative Algebras, Orthogonal Polynomials and Operators
Sammanfattning : The main object studied in this thesis is the multi-parametric family of unital associative complex algebras generated by the element $Q$ and the finite or infinite set $\{S_j\}_{j\in J}$ of elements satisfying the commutation relations $S_jQ=\sigma_j(Q)S_j$, where $\sigma_j$ is a polynomial for all $j\in J$. A concrete representation is given by the operators $Q_x(f)(x)=xf(x)$ and $\alpha_{\sigma_j}(f)(x)=f(\sigma_j(x))$ acting on polynomials or other suitable functions. LÄS MER
9. Symplectic methods for isospectral flows and 2D ideal hydrodynamics
Sammanfattning : The numerical solution of non-canonical Hamiltonian systems is an active and still growing field of research. At the present time, the biggest challenges concern the realization of structure preserving algorithms for differential equations on infinite dimensional manifolds. LÄS MER
10. Vector-valued Eisenstein series of congruence types and their products
Sammanfattning : Historically, Kohnen and Zagier connected modular forms with period polynomials, and as a consequence of this association concluded that the products of at most two Eisenstein series span all spaces of classical modular forms of level 1. Later Borisov and Gunnells among other authors extended the result to higher levels. LÄS MER
