Sökning: "George Baravdish"

Hittade 5 avhandlingar innehållade orden George Baravdish.

  1. 1. Inverse Mathematical Models for Brain Tumour Growth

    Författare :Rym Jaroudi; George Baravdish; Tomas Johansson; Trucu Dumitru; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : We study the following well-established model of reaction-diffusion type for brain tumour growth:This equation describes the change over time of the normalised tumour cell density u as a consequence of two biological phenomena: proliferation and diffusion.We discuss a mathematical method for the inverse problem of locating the brain tumour source (origin) based on the reaction-diffusion model. LÄS MER

  3. 2. Inverse Problems for Tumour Growth Models and Neural ODEs

    Författare :Rym Jaroudi; George Baravdish; Tomas Johansson; Jonas Unger; Gabriel Eilertsen; Lukáš Malý; Torbjörn Lundh; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis concerns the application of methods and techniques from the theory of inverse problems and differential equations to study models arising in the areas of mathematical oncology and deep learning. The first problem studied is to develop methods to perform numerical simulations with full 3-dimensional brain imaging data of reaction-diffusion models for tumour growth forwards as well as backwards in time with the goal of enabling the numerical reconstruction of the source of the tumour given an image (or similar data) at a later stage in time of the tumour. LÄS MER

  4. 3. Reconstruction of flow and temperature from boundary data

    Författare :Tomas Johansson; Vladimir Kozlov; George Bastay (Baravdish); Jürgen Rossmann; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Partiella differentialekvationer; Operatorteori;

    Sammanfattning : In this thesis, we study Cauchy problems for elliptic and parabolic equations. These include the stationary Stokes system and the heat equation. Data are given on a part of the boundary of a bounded domain. The aim is to reconstruct the solution from these data. LÄS MER

  5. 4. The Use of Landweber Algorithm in Image Reconstruction

    Författare :Touraj Nikazad; Tommy Elfving; George Baravdish; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; convex feasibility; projection methods; simultaneous algorithms; iterative methods; stopping rules; semi-convergence; Numerical analysis; Numerisk analys;

    Sammanfattning : Ill-posed sets of linear equations typically arise when discretizing certain types of integral transforms. A well known example is image reconstruction, which can be modelled using the Radon transform. After expanding the solution into a finite series of basis functions a large, sparse and ill-conditioned linear system arises. LÄS MER

  7. 5. Variational Tensor-Based Models for Image Diffusion in Non-Linear Domains

    Författare :Freddie Åström; Michael Felsberg; George Baravdish; Reiner Lenz; Christoph Schnörr; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; image diffusion; variational formulation; denoising; tensor; non-linear;

    Sammanfattning : This dissertation addresses the problem of adaptive image filtering.Although the topic has a long history in the image processing community, researchers continuously present novel methods to obtain ever better image restoration results. LÄS MER