Sökning: "stochastic differential equations"

Visar resultat 16 - 20 av 88 avhandlingar innehållade orden stochastic differential equations.

1. 16. Coarse Graining Monte Carlo Methods for Wireless Channels and Stochastic Differential Equations

   Författare :Håkon Hoel; Anders Szepessy; Ola Hössjer; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Coarse graining; Monte Carlo Methods; Stochastic processes; Numerical analysis; Numerisk analys;

   Sammanfattning : This thesis consists of two papers considering different aspects of stochastic process modelling and the minimisation of computational cost. In the first paper, we analyse statistical signal properties and develop a Gaussian pro- cess model for scenarios with a moving receiver in a scattering environment, as in Clarke’s model, with the generalisation that noise is introduced through scatterers randomly flip- ping on and off as a function of time. LÄS MER

3. 17. Identification and Estimation for Models Described by Differential-Algebraic Equations

   Författare :Markus Gerdin; Torkel Glad; Lennart Ljung; Manfred Deistler; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Differential-Algebraic Equations; Identifiability; Nonlinear systems; Modelling; Identification; Descriptor systems; Automatic control; Reglerteknik;

   Sammanfattning : Differential-algebraic equations (DAEs) form the natural way in which models of physical systems are delivered from an object-oriented modeling tool like Modelica. Differential-algebraic equations are also known as descriptor systems, singular systems, and implicit systems. LÄS MER

4. 18. On weak and strong convergence of numerical approximations of stochastic partial differential equations

   Författare :Fredrik Lindgren; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Additive noise; Cahn-Hilliard-Cook equation; Error estimate; Finite element; Hyperbolic equation; Parabolic equation; Rational approximation; Stochastic partial differential equation; Strong convergence; Truncation; Wiener process; Weak convergence; Weak convergence;

   Sammanfattning : This thesis is concerned with numerical approximation of linear stochastic partial differential equations driven by additive noise. In the first part, we develop a framework for the analysis of weak convergence and within this framework we analyze the stochastic heat equation, the stochastic wave equation, and the linearized stochastic Cahn-Hilliard, or the linearized Cahn-Hilliard-Cook equation. LÄS MER

5. 19. A contribution to population dynamics in space

   Författare :Nikias Sarafoglou; Å.E. Andersson; Umeå universitet; []
   Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Population growth; population age structure; migration; labour market; housing market; production function; stochastic differential equations; partial differential equations;

   Sammanfattning : Population models are very often used and considered useful in the policy-making process and for planning purposes. In this research I have tried to illuminate the problem of analysing population evolution in space by using three models which cover a wide spectrum of complementary methodologies:a The Hotell. LÄS MER

7. 20. Contributions to nonlinear mixed-effects modeling

   Författare :Jacob Leander; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; nonlinear mixed-effects models; stochastic differential equations; parameter estimation; extended Kalman filter; sensitivity equations; stochastic differential equations;

   Sammanfattning : The topic of this thesis is nonlinear mixed-effects models. A nonlinear mixed-effects model is a hierarchical regression model used to analyze measurements from several individuals simultaneously, which allows sharing of information between similar individuals. LÄS MER