Sökning: "Initial value problem"

Visar resultat 1 - 5 av 79 avhandlingar innehållade orden Initial value problem.

  1. 1. On the discretization in time and space of parabolic integro-differential equations

    Författare :Nai-Ying Zhang; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; initial-boundary value problem; parabolic; partial; integro-differential equation; regularity; nonsmooth initial data; finite element method; fully discrete; Galerkin approximation; stability; error estimate; quadrature; stability;

    Sammanfattning : .... LÄS MER

  3. 2. Essays on Microeconometrics and Immigrant Assimilation

    Författare :Alpaslan Akay; Göteborgs universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Average marginal effect; Marginal effect of the average individual; Employment and earnings assimilation; Quasi-fixed effects approach; Initial value problem; Dynamic censored random-effects model; Monte Carlo experiment; Heckman’s approximation; Simple method of Wooldridge; Dynamic random-effects sample-selection model; wage-curve method;

    Sammanfattning : Paper I. Asymptotic bias reduction for a conditional marginal effects estimator in sam- ple selection models. In this article we discuss the di¤erences between the average marginal effect and the mar- ginal effect of the average individual in sample selection models, estimated by the Heck- man procedure. LÄS MER

  4. 3. Initial-Boundary-Value Problems for the Stokes and Navier–Stokes Equations on Staggered Grids

    Författare :Jonas Nilsson; Bertil Gustafsson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Stokes equations; Navier-Stokes equations; boundary conditions; staggered grids; higher-order methods; Numerical Analysis; Numerisk analys;

    Sammanfattning : In the first part of the thesis various types of boundary conditions for the steady state Stokes equations are considered. We formulate the boundary conditions in a new way, such that the boundary value problem becomes non-singular, and derive estimates of the solution. LÄS MER

  5. 4. Utilizing Problem Structure in Optimization of Radiation Therapy

    Författare :Fredrik Carlsson; Anders Forsgren; Edwin Romeijn; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Optimization; intensity-modulated radiation therapy; conjugate-gradient method; step-and-shoot delivery; column generation; quasi-Newton method; regularization; sequential quadratic programming; Optimization; systems theory; Optimeringslära; systemteori;

    Sammanfattning : In this thesis, optimization approaches for intensity-modulated radiation therapy are developed and evaluated with focus on numerical efficiency and treatment delivery aspects. The first two papers deal with strategies for solving fluence map optimization problems efficiently while avoiding solutions with jagged fluence profiles. LÄS MER

  7. 5. Unlocking the Potential of Brewer’s Spent Grain : Sustainable Biorefinery Approach and Value-Added Product Generation

    Författare :Mohsen Parchami; Mohammad J Taherzadeh; Sudip Rakshit; Högskolan i Borås; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Brewer s spent grain; Hydrothermal pretreatment; Organosolv pretreatment; Edible filamentous fungi; Anaerobic digestion; Biorefinery; Resource Recovery; Resursåtervinning;

    Sammanfattning : Brewer’s spent grain (BSG) constitutes 85% of brewing byproducts and 30% of initial malt. In 2021, BSG production reached approximately 37.2 million tons. Owing to its high moisture and nutritional content, BSG is prone to biological deterioration, causing environmental issues when discarded as waste. LÄS MER