Sökning: "Approximation theory"
Visar resultat 11 - 15 av 395 avhandlingar innehållade orden Approximation theory.
11. Extreme points of the Vandermonde determinant in numerical approximation, random matrix theory and financial mathematics
Sammanfattning : This thesis discusses the extreme points of the Vandermonde determinant on various surfaces, their applications in numerical approximation, random matrix theory and financial mathematics. Some mathematical models that employ these extreme points such as curve fitting, data smoothing, experimental design, electrostatics, risk control in finance and method for finding the extreme points on certain surfaces are demonstrated. LÄS MER
12. Inverse Problems in Analytic Interpolation for Robust Control and Spectral Estimation
Sammanfattning : This thesis is divided into two parts. The first part deals with theNevanlinna-Pick interpolation problem, a problem which occursnaturally in several applications such as robust control, signalprocessing and circuit theory. We consider the problem of shaping andapproximating solutions to the Nevanlinna-Pick problem in a systematicway. LÄS MER
13. Model Vertices Beyond the GW Approximation
Sammanfattning : We study the effects of local vertex corrections to the self energy of the electron gas. We find that a vertex derived from time-dependent density-functional theory can give accurate self energies without including the explicit time dependence of the exchange-correlation potential provided, however, that a proper decay at large momentum transfer (large q) is built into the vertex function. LÄS MER
14. Approximating Stochastic Partial Differential Equations with Finite Elements: Computation and Analysis
Sammanfattning : Stochastic partial differential equations (SPDE) must be approximated in space and time to allow for the simulation of their solutions. In this thesis fully discrete approximations of such equations are considered, with an emphasis on finite element methods combined with rational semigroup approximations. LÄS MER
15. Machine Learning Methods Using Class-specific Subspace Kernel Representations for Large-Scale Applications
Sammanfattning : Kernel techniques became popular due to and along with the rising success of Support Vector Machines (SVM). During the last two decades, the kernel idea itself has been extracted from SVM and is now widely studied as an independent subject. LÄS MER