Sökning: "Euclidean geometry"

Visar resultat 16 - 20 av 26 avhandlingar innehållade orden Euclidean geometry.

1. 16. Manifold learning and representations for image analysis and visualization

   Författare :Anders Brun; Hans Knutsson; Magnus Herberthson; Carl-Fredrik Westin; Reiner Lenz; Linköpings universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; manifold learning; image analysis; signal processing; diffusion tensor mri; Medical informatics; Medicinsk informatik;

   Sammanfattning : We present a novel method for manifold learning, i.e. identification of the low-dimensional manifold-like structure present in a set of data points in a possibly high-dimensional space. The main idea is derived from the concept of Riemannian normal coordinates. LÄS MER

3. 17. Nonlinear elliptic problems with boundary blow-up

   Författare :Jerk Matero; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mathematics; Boundary blow-up; NTA domain; fractal; p-Laplaceoperator; Mange-Ampère operator; viscosity solution; mean curvature flow; gradient estimate; Fefferman s equation; superdiffusion; entire solution; maximum principle; Primary 35J65; MATEMATIK; MATHEMATICS; MATEMATIK; matematik; Mathematics;

   Sammanfattning : A classical problem in differential geometry is the prescribed curvature problemin a bounded domain, where the task is to conformally deform the Euclidean metric to another complete Riemannian metric with a prescribed curvature function.If this function is negative, the problem is equivalent to solving a nonlinear elliptic partial differential equation with boundary blow-up. LÄS MER

4. 18. Perceptually motivated speech recognition and mispronunciation detection

   Författare :Christos Koniaris; Olov Engwall; Martin Cooke; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; feature extraction; feature selection; auditory models; MFCCs; speech recognition; distortion measures; perturbation analysis; psychoacoustics; human perception; sensitivity matrix; pronunciation error detection; phoneme; second language; perceptual assessment;

   Sammanfattning : This doctoral thesis is the result of a research effort performed in two fields of speech technology, i.e., speech recognition and mispronunciation detection. Although the two areas are clearly distinguishable, the proposed approaches share a common hypothesis based on psychoacoustic processing of speech signals. LÄS MER

5. 19. Twisting and Turning in Six Dimensions

   Författare :Hampus Linander; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; 0 theory; 2; Yang-Mills theory; Topological twisting; Circle fibrations; Compactification; Supersymmetry; Topological field theory;

   Sammanfattning : This thesis investigates certain aspects of a six-dimensional quantum theoryknown as (2,0) theory. This theory is maximally supersymmetric and conformal,making it the most symmetric higher dimensional quantum theory known. It hasresisted an explicit construction as a quantum field theory yet its existence can beinferred from string theory. LÄS MER

7. 20. Some Cases of Kudla’s Modularity Conjecture for Unitary Shimura Varieties

   Författare :Jiacheng Xia; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; special cycles; Eisenstein series; spherical designs; central L-values; unitary Shimura varieties; Jacobi forms; rational points; generating functions; the circle method; Kudla s modularity conjecture; theta series; Rankin--Selberg method;

   Sammanfattning : A common theme of the thesis is the interplay of symmetry and rigidity, which is a general phenomenon in mathematics. Symmetry is a notion related to the degree to which an object remains unchanged under transformations, and rigidity is a notion that in terms of physics can be thought of as a lack of freedom, which leads to stronger properties of an object than we normally expect. LÄS MER