Search for dissertations about: "symmetric tensors"

Showing result 1 - 5 of 9 swedish dissertations containing the words symmetric tensors.

2. 1. Families of cycles and the Chow scheme

   Author : David Rydh; Dan Laksov; Martin Olsson; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Families of cycles; Chow scheme; Hilbert scheme; zero-cycles; divided powers; symmetric tensors; symmetric product; Weil restriction; norm functor; Algebra and geometry; Algebra och geometri;

   Abstract : The objects studied in this thesis are families of cycles on schemes. A space — the Chow variety — parameterizing effective equidimensional cycles was constructed by Chow and van der Waerden in the first half of the twentieth century. Even though cycles are simple objects, the Chow variety is a rather intractable object. READ MORE

4. 2. Algorithms in data mining using matrix and tensor methods

   Author : Berkant Savas; Lars Eldén; Lieven De Lathauwer; Linköpings universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Volume; Minimization criterion; Determinant; Rank deficient matrix; Reduced rank regression; System identification; Rank reduction; Volume minimization; General algorithm; Handwritten digit classification; Tensors; Higher order singular value decomposition; Tensor approximation; Least squares; Tucker model; Multilinear algebra; Notation; Contraction; Tensor matricization; Newton s method; Grassmann manifolds; Product manifolds; Quasi-Newton algorithms; BFGS and L-BFGS; Symmetric tensor approximation; Local intrinsic coordinates; Global embedded coordinates; ; Numerical analysis; Numerisk analys;

   Abstract : In many fields of science, engineering, and economics large amounts of data are stored and there is a need to analyze these data in order to extract information for various purposes. Data mining is a general concept involving different tools for performing this kind of analysis. READ MORE

5. 3. New Techniques for Estimation of Source Parameters : Applications to Airborne Gravity and Pseudo-Gravity Gradient Tensors

   Author : Majid Beiki; Laust Pedersen; Mehrdad Bastani; Mark Pilkington; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Gravity gradient tensor; pseudo-gravity; magnetic field; eigenvector analysis; least squares algorithm; strike direction; source parameter estimation; analytic signal; Euler deconvolution; joint inversion; infinite dike model; geological contact model; Solid earth physics; Fasta jordens fysik; Geophysics with specialization in Solid Earth Physics; Geofysik med inriktning mot fasta jordens fysik;

   Abstract : Gravity gradient tensor (GGT) data contains the second derivatives of the Earth’s gravitational potential in three orthogonal directions. GGT data can be measured either using land, airborne, marine or space platforms. READ MORE

6. 4. Development of a water model with arbitrary rank multipolar polarization, repulsion and electrostatics

   Author : Jonatan Öström; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; teoretisk fysik; Theoretical Physics;

   Abstract : I report on the derivation, development and computer implementation of methods for computing the energies and forces between small rigid polarizable molecules, that are defined by the center-of-mass moments of their electronic and nuclear charge distributions and their linear response moments. The formalism is based on compact and efficient storage and manipulation of symmetric Cartesian tensors of arbitrary rank, and a general formula for the Cartesian gradients of one-dimensional interaction (kernel) potentials. READ MORE

7. 5. Conformal Einstein spaces and Bach tensor generalization in n dimensions

   Author : Jonas Bergman Ärlebäck; Brian Edgar; Magnus Herberthson; Mattias Marklund; Linköpings universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; MATHEMATICS; MATEMATIK;

   Abstract : In this thesis we investigate necessary and su±cient conditions for an n-dimensional space, n ≥ 4, to be locally conformal to an Einstein space. After reviewing the classical results derived in tensors we consider the four-dimensional spinor result of Kozameh, Newman and Tod. READ MORE