Search for dissertations about: "equation"

Showing result 21 - 25 of 1350 swedish dissertations containing the word equation.

2. 21. High Order Symmetric Finite Difference Schemes for the Acoustic Wave Equation

   Author : Abraham Zemui; Bertil Gustafsson; Leif Abrahamsson; Per Weinerfelt; Uppsala universitet; []
   Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; finite element method; mass lumping; high order; finite difference method; wave equation; Numerical Analysis; Numerisk analys;

   Abstract : When someone speaks, or when a piano is played, sound waves are spread through the room. Physically the propagation of sound is governed by the acoustic wave equation. This thesis deals with the problem of finding solutions to this equation by numerical methods. READ MORE

4. 22. A Fast Method for Solving the Helmholtz Equation Based on Wave Splitting

   Author : Jelena Popovic; Olof Runborg; Elisabeth Larsson; KTH; []
   Keywords : Helmholtz equation; high fequency waves;

   Abstract : In this thesis, we propose and analyze a fast method for computing the solution of the Helmholtz equation in a bounded domain with a variable wave speed function. The method is based on wave splitting. The Helmholtz equation is first split into one--way wave equations which are then solved iteratively for a given tolerance. READ MORE

5. 23. Developments in the theory of the Prigogine-Herman kinetic equation of vehicular traffic

   Author : Alexandros Sopasakis; Partiella differentialekvationer; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Chapman-Enskog expansion; Traffic; Prigogine-Herman; Kinetic equation; Unstable flow;

   Abstract : The nonlinear kinetic equation of Prigogine and Herman is examined in regards to existence and uniqueness of solutions. The solution exists and is unique in the Banach space of bounded continuous functions over a particular subspace Ω. READ MORE

6. 24. On Numerical Methods for the Diffusion Equation Subject to Non-Local Boundary Conditions

   Author : Gunnar Ekolin; Göteborgs universitet; Göteborgs universitet; Gothenburg University; []
   Keywords : forward Euler method; backward Euler method; the Crank-Nicolson method; heat equation; Galerkin finite element methods; backward Euler method;

   Abstract : In the first paper three different finite difference methods for solving the heat equation in one space dimension with boundary conditions containing integrals over the interior of the interval are considered. The schemes are based on the forward Euler, the backward Euler and the Crank-Nicolson methods. Error estimates are derived in maximum norm. READ MORE

7. 25. Automatic Parallelization using Pipelining for Equation-Based Simulation Languages

   Author : Håkan Lundvall; Peter Fritzson; Welf Löwe; Linköpings universitet; []
   Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Equation-Based languages; automatic parallelization; Modelica; simulation; Ekvationsbaserade språk; automatisk parallellisering; Modelica; simulering; Computer science; Datalogi;

   Abstract : During the most recent decades modern equation-based object-oriented modeling and simulation languages, such as Modelica, have become available. This has made it easier to build complex and more detailed models for use in simulation. READ MORE