Sökning: "Second-order functions"
Visar resultat 21 - 25 av 56 avhandlingar innehållade orden Second-order functions.
21. Towards a relativistically covariant many-body perturbation theory - With numerical implementation to helium-like ions
Sammanfattning : The experimental results for simple atomic systems have become more and more accurate and in order to keep up with the experimental achievements the theoretical procedures have to be refined. Recent accurate experimental results obtained for helium-like ions in the low- and moderate-Z regions proclaim the importance of theoretical calculations that combines relativistic, QED and electron correlation effects. LÄS MER
22. The Double Layer Potential Operator Through Functional Calculus
Sammanfattning : Layer potential operators associated to elliptic partial differential equations have been an object of investigation for more than a century, due to their contribution in the solution of boundary value problems through integral equations.In this Licentiate thesis we prove the boundedness of the double layer potential operator on the Hilbert space of square integrable functions on the boundary, associated to second order uniformly elliptic equations in divergence form in the upper half-space, with real, possibly non-symmetric, bounded measurable coefficients, that do not depend on the variable transversal to the boundary. LÄS MER
23. Enhancement, Detection, and Visualization of 3D Volume Data
Sammanfattning : Three-dimensional (3D) volume data become increasingly common with the emergence and wide availability of modern 3D image acquisition techniques. The demand for computerized analysis and visualization techniques is constantly growing to utilize the abundant information embedded in these data.This thesis consists of two parts. LÄS MER
24. Theoretical Studies on Electronic Structure, Spectra and Conductivity of Pristine and Alkali Doped Polyacetylene
Sammanfattning : The present thesis is a theoretical investigation of the electronic properties of linear polyenes to get an insight into conductive phenomena in pristine and doped polyacetylene. Conductivity in polyacetylene is a complex phenomena and cannot be treated within simple band models. LÄS MER
25. Weighted inequalities involving Hardy-type and limiting geometric mean operators
Sammanfattning : This thesis consists of an introduction and five papers, which all are devoted to different questions connected to weighted Hardy-type inequalities and their generalizations. The introduction gives an elementary overview of the area and serves as a frame for the following papers. In particular, it is pointed out where the obtained results fit in. LÄS MER
