Sökning: "finite difference methods"

Visar resultat 6 - 10 av 149 avhandlingar innehållade orden finite difference methods.

1. 6. Uncertainty Quantification and Numerical Methods for Conservation Laws

   Författare :Per Pettersson; Jan Nordström; Gianluca Iaccarino; Gunilla Kreiss; Rémi Abgrall; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; uncertainty quantification; polynomial chaos; stochastic Galerkin methods; conservation laws; hyperbolic problems; finite difference methods; finite volume methods; Beräkningsvetenskap med inriktning mot numerisk analys; Scientific Computing with specialization in Numerical Analysis;

   Sammanfattning : Conservation laws with uncertain initial and boundary conditions are approximated using a generalized polynomial chaos expansion approach where the solution is represented as a generalized Fourier series of stochastic basis functions, e.g. orthogonal polynomials or wavelets. LÄS MER

3. 7. Adaptive methods in computational electromagnetics

   Författare :Pär Ingelström; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; finite elements; hybris methods; finite-difference time-domain; error estimation; mesh refinement; Padé approximation;

   Sammanfattning : .... LÄS MER

4. 8. Stable and High-Order Finite Difference Methods for Multiphysics Flow Problems

   Författare :Jens Berg; Jan Nordström; Per Lötstedt; David Zingg; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Summation-by-parts; Simultaneous Approximation Term; Stability; High-order accuracy; Finite difference methods; Dual consistency; Beräkningsvetenskap med inriktning mot numerisk analys; Scientific Computing with specialization in Numerical Analysis;

   Sammanfattning : Partial differential equations (PDEs) are used to model various phenomena in nature and society, ranging from the motion of fluids and electromagnetic waves to the stock market and traffic jams. There are many methods for numerically approximating solutions to PDEs. LÄS MER

5. 9. Finite Difference and Discontinuous Galerkin Methods for Wave Equations

   Författare :Siyang Wang; Gunilla Kreiss; Thomas Hagstrom; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Wave propagation; Finite difference method; Discontinuous Galerkin method; Stability; Accuracy; Summation by parts; Normal mode analysis; Beräkningsvetenskap med inriktning mot numerisk analys; Scientific Computing with specialization in Numerical Analysis;

   Sammanfattning : Wave propagation problems can be modeled by partial differential equations. In this thesis, we study wave propagation in fluids and in solids, modeled by the acoustic wave equation and the elastic wave equation, respectively. LÄS MER

7. 10. High order summation-by-parts methods in time and space

   Författare :Tomas Lundquist; Jan Nordström; Peter Eliasson; David A. Kopriva; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; summation-by-parts; time integration; stiff problems; weak initial conditions; high order methods; simultaneous-approximation-term; finite difference; discontinuous Galerkin; spectral methods; conservation; energy stability; complex geometries; non-conforming grid interfaces; interpolation;

   Sammanfattning : This thesis develops the methodology for solving initial boundary value problems with the use of summation-by-parts discretizations. The combination of high orders of accuracy and a systematic approach to construct provably stable boundary and interface procedures makes this methodology especially suitable for scientific computations with high demands on efficiency and robustness. LÄS MER