Sökning: "Shape analysis"

Visar resultat 16 - 20 av 948 avhandlingar innehållade orden Shape analysis.

1. 16. Some properties of one and twophase quadrature domains

   Författare :Mahmoudreza Bazarganzadeh; Henrik Shahgholian; Boris Shapiro; Anzdrej Szulkin; Stockholm University Department of Mathematics; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quadrature domain; Two- phase problems; Uniqueness; Free boundary problem; Level set method; Shape optimization. 2000 MSC: Primary 35R35; Secondary 35B06; 76D27; 49Q10;

   Sammanfattning : .... LÄS MER

3. 17. Adjoint-based aerodynamic shape optimization

   Författare :Olivier Amoignon; Martin Berggren; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Numerical Analysis; Numerisk analys;

   Sammanfattning : An adjoint system of the Euler equations of gas dynamics is derived in order to solve aerodynamic shape optimization problems with gradient-based methods. The derivation is based on the fully discrete flow model and involves differentiation and transposition of the system of equations obtained by an unstructured and node-centered finite-volume discretization. LÄS MER

4. 18. On Modelling Nonlinear Variation in Discrete Appearances of Objects

   Författare :Felix Wehrmann; Ewert Bengtsson; Lennart Thurfjell; Fredrik Bergholm; Timothy Cootes; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bildanalys; image analysis; shape description; nonlinear modelling; manifold reconstruction; auto-associative neural network; Bildanalys; Image analysis; Bildanalys;

   Sammanfattning : Mathematical models of classes of objects can significantly contribute to the analysis of digital images. A major problem in modelling is to establish suitable descriptions that cover not only a single object but also the variation that is usually present within a class of objects. LÄS MER

5. 19. Shape and material optimization for antenna applications

   Författare :Per Jacobsson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; explicit-implicit time stepping; sensitivity analysis; Nitsche s method; total scattering cross section; shape and material optimization; array antennas; finite element method;

   Sammanfattning : In this thesis, a gradient-based method for shape and material optimization fortwo antenna applications is presented: minimization of the active reflectioncoefficient for conformal array antennas; and minimization of the totalscattering cross section for cylindrical scatterers. The sensitivity of theobjective function with respect to changes of the shape and material of the geometry isexpressed in terms of the original field problem and an adjoint field problem. LÄS MER

7. 20. Methods for the analysis and characterization of brain morphology from MRI images

   Författare :Irene Brusini; Chunliang Wang; Örjan Smedby; Eric Westman; Lars-Olof Wahlund; Jorge Cardoso; KTH; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Brain MRI; Image Segmentation; Machine Learning; Deep Learning; Shape Analysis; Aging; Neurodegeneration; MRT av hjärnan; Bildsegmentering; Maskininlärning; Djupinlärning; Formanalys; Åldrande; Neurodegeneration; Medical Technology; Medicinsk teknologi;

   Sammanfattning : Brain magnetic resonance imaging (MRI) is an imaging modality that produces detailed images of the brain without using any ionizing radiation. From a structural MRI scan, it is possible to extract morphological properties of different brain regions, such as their volume and shape. LÄS MER