Sökning: "stochastic simulation"

Visar resultat 11 - 15 av 233 avhandlingar innehållade orden stochastic simulation.

  1. 11. Stochastic Modeling and Simulation of the TCP protocol

    Författare :Jörgen Olsén; Ingemar Kaj; Joachim Charzinski; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mathematical statistics; TCP; flow-control; network simulator; ns-2; stochastic modeling; throughput; packet loss rate; fixed-point method; Matematisk statistik; Mathematical statistics; Matematisk statistik;

    Sammanfattning : The success of the current Internet relies to a large extent on a cooperation between the users and the network. The network signals its current state to the users by marking or dropping packets. The users then strive to maximize the sending rate without causing network congestion. LÄS MER

  3. 12. LES stochastic modelling of cavitation with its applications in OpenFOAM

    Författare :Boxiong Chen; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Rayleigh-Plesset Equation; Cavitation; Modelling; Simulation; Eulerian Stochastic Field Method; OpenFOAM; Homogeneous Equilibrium Model;

    Sammanfattning : Cavitation is a vaporization process that commonly happens in high-pressure injector nozzles nowadays. It has been shown by previous studies that cavitation has a significant influence on the subsequent atomization process, the quality of which would in turn heavily affect the process of combustion. LÄS MER

  4. 13. Stochastic Reactor Models for Engine Simulations

    Författare :Martin Tunér; Förbränningsmotorer; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; SRM; Stochastic Reactor Model; Engine Simulation; Chemical kinetics; HCCI; Direct injection; Combustion; NVO; Modeling; PDF;

    Sammanfattning : The aim of the thesis work is the further development of practical engine simulation tools based on Stochastic Reactor Models, SRMs. Novel and efficient implementations were made of a variety of SRMs adapted to different engine types. The models in question are the HCCI-SRM, the TwoZone SI-SRM and the DI-SRM. LÄS MER

  5. 14. Approximation of Infinitely Divisible Random Variables with Application to the Simulation of Stochastic Processes

    Författare :Magnus Wiktorsson; Matematisk statistik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; operations research; Statistics; aktuariematematik; Stochastic differential equation; Infinitely divisible distribution; Type G distribution; Lévy process; Stochastic integral; Mathematical Statistics; Matematik; Mathematics; programming; actuarial mathematics; Statistik; operationsanalys; programmering;

    Sammanfattning : This thesis consists of four papers A, B, C and D. Paper A and B treats the simulation of stochastic differential equations (SDEs). The research presented therein was triggered by the fact that there were not any efficient implementations of the higher order methods for simulating SDEs. LÄS MER

  7. 15. Identification of Stochastic Nonlinear Dynamical Models Using Estimating Functions

    Författare :Mohamed Abdalmoaty; Håkan Hjalmarsson; Adrian Wills; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Prediction Error Method; Maximum Likelihood; Data-driven; Learning; Stochastic; Nonlinear; Dynamical Models; Non-stationary Linear Predictors; Intractable Likelihood; Latent Variable Models; Estimation; Process Disturbance; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : Data-driven modeling of stochastic nonlinear systems is recognized as a very challenging problem, even when reduced to a parameter estimation problem. A main difficulty is the intractability of the likelihood function, which renders favored estimation methods, such as the maximum likelihood method, analytically intractable. LÄS MER