Sökning: "equations"

Visar resultat 16 - 20 av 1691 avhandlingar innehållade ordet equations.

1. 16. Convergence rates of adaptive algorithms for deterministic and stochastic differential equations

   Författare :Kyoung-Sook Moon; KTH; []
   Nyckelord :adaptive mesh refinement algorithm; computational complexity; a posteriori error estimate; ordinary differential equations; stochastic differential equations;

   Sammanfattning : .... LÄS MER

3. 17. Optimal Switching Problems and Related Equations

   Författare :Marcus Olofsson; Kaj Nyström; Saïd Hamadène; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; optimal switching; stochastic control; variational inequalities; backward stochastic differential equations; incomplete information; stochastic filtering; Mathematics; Matematik;

   Sammanfattning : This thesis consists of five scientific papers dealing with equations related to the optimal switching problem, mainly backward stochastic differential equations and variational inequalities. Besides the scientific papers, the thesis contains an introduction to the optimal switching problem and a brief outline of possible topics for future research. LÄS MER

4. 18. Geometric Methods for some Nonlinear Wave Equations

   Författare :Jonatan Lenells; Matematik (naturvetenskapliga fakulteten); []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Natural science; Geodesic flow; Nonlinear wave equations; Geometric methods; Naturvetenskap;

   Sammanfattning : A number of results related to the geometric interpretation of some dispersive nonlinear wave equations are presented. It is first described how some well-known shallow water equations arise geometrically as Euler equations for the geodesic flow on the Virasoro group endowed with certain right-invariant metrics. LÄS MER

5. 19. Hybrid Solvers for the Maxwell Equations in Time-Domain

   Författare :Fredrik Edelvik; Per Lötstedt; Jan Hesthaven; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Maxwell s equations; time-domain; finite volume methods; finite element methods; hybrid solver; dispersive materials; thin wires; Beräkningsvetenskap; Scientific Computing;

   Sammanfattning : The most commonly used method for the time-domain Maxwell equations is the Finite-Difference Time-Domain method (FDTD). This is an explicit, second-order accurate method, which is used on a staggered Cartesian grid. The main drawback with the FDTD method is its inability to accurately model curved objects and small geometrical features. LÄS MER

7. 20. Topics in Nonlinear Elliptic Differential Equations

   Författare :Shoyeb Waliullah; Andrzej Szulkin; Thomas Bartsch; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Concentration-compactness principle; critical Sobolev exponent; symmetric solutions of elliptic equations; degenerate elliptic equation; Nehari manifold; Caffarelli-Kohn-Nirenberg inequality; infinitely many solutions; MATHEMATICS; MATEMATIK; Mathematics; matematik;

   Sammanfattning : In this thesis we examine the existence of solutions to nonlinear elliptic partial differential equations via variational methods.In Paper I we consider the existence of constrained minimizers which correspond to solutions of equations involving the iterated Laplacian, the iterated p-Laplacian and the critical Sobolev exponent. LÄS MER