Sökning: "Monte Carlo simulations"

Visar resultat 26 - 30 av 441 avhandlingar innehållade orden Monte Carlo simulations.

1. 26. Computer Simulations in Materials Physics: Time-scales and Accuracy

   Författare :Urban Engberg; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; basis sets; computer simulations; pseudopotentials; materials physics; density functional theory; transition state theory; O N ; quantum Monte Carlo;

   Sammanfattning : Computer simulations are expected to play an increasingly important role within materials physics in the future. Owing to a combination of accurate physical approximations, improved implementations of these approximations, and the exponentially increasing power of computers, problems can now be solved on length and time-scales which were unimaginable only a decade ago. LÄS MER

3. 27. Computational Aspects of Lévy-Driven SPDE Approximations

   Författare :Andreas Petersson; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; multilevel Monte Carlo; numerical approximation of stochastic differential equations; multiplicative noise; Lévy processes; finite element method; variance redons; Monte Carlo; weak convergence; Lévy processes;

   Sammanfattning : In order to simulate solutions to stochastic partial differential equations (SPDE) they must be approximated in space and time. In this thesis such fully discrete approximations are considered, with an emphasis on finite element methods combined with rational semigroup approximations. There are several notions of the error resulting from this. LÄS MER

4. 28. Variance reduction methods for numerical solution of plasma kinetic diffusion

   Författare :Lars Josef Höök; Torbjörn Hellsten; Thomas Johnson; Lars-Göran Ericsson; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; variance reduction; Monte Carlo; quasi-Monte Carlo; kinetic diffusion; stochastic differential equation;

   Sammanfattning : Performing detailed simulations of plasma kinetic diffusion is a challenging task and currently requires the largest computational facilities in the world. The reason for this is that, the physics in a confined heated plasma occur on a broad range of temporal and spatial scales. LÄS MER

5. 29. Approximating Stochastic Partial Differential Equations with Finite Elements: Computation and Analysis

   Författare :Andreas Petersson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Lévy process; Lyapunov equation; white noise; finite element method; multilevel Monte Carlo; Monte Carlo; multiplicative noise; asymptotic mean square stability; stochastic heat equation; covariance operator; weak convergence; generalized Wiener process; numerical approximation; stochastic wave equation; Stochastic partial differential equations;

   Sammanfattning : Stochastic partial differential equations (SPDE) must be approximated in space and time to allow for the simulation of their solutions. In this thesis fully discrete approximations of such equations are considered, with an emphasis on finite element methods combined with rational semigroup approximations. LÄS MER

7. 30. Theoretical Studies Using Simple Ionic Liquid Models

   Författare :Hongduo Lu; Beräkningskemi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Room Temperature Ionic Liquids; Coarse-Grained Models; Differential Capacitance; Monte Carlo; Classical Density Functional Theory; Room Temprerature Ionic Luqids; coarse-grained model; differential capacitance; Monte Carlo simulation; Classical Density Functional Theory;

   Sammanfattning : Room Temperature Ionic Liquids (RTILs) are organic salts that melt below 100 degrees Celsius. The advantages of RTILs, such as high ionic concentrations and low melting points, promote several potential applications. For instance, RTILs could be utilized in manufacturing energy storage devices, and as efficient solvents. LÄS MER