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Found 4 swedish dissertations matching the above criteria.

  2. 1. Computational algorithms for algebras

    Author : Samuel Lundqvist; Clas Löfwall; Ralf Fröberg; H. Michael Möller; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Hilbert function; Gröbner basis; zero-dimensional ideal; affine variety; projective variety; run-time complexity; Algebra and geometry; Algebra och geometri; Mathematics; matematik;

    Abstract : This thesis consists of six papers. In Paper I, we give an algorithm for merging sorted lists of monomials and together with a projection technique, we obtain a new complexity bound for the Buchberger-Möller algorithm and the FGLM algorithm. READ MORE

  4. 2. Modelling of Quantum Transport in Nanostructures

    Author : Dan Csontos; Fasta tillståndets fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; ballistic transport; quantum wire; quantum dot; resonant tunnelling; three-terminal; disorder; Physics; Fysik; Fysicumarkivet A:2002:Csontos; scattering matrix; quantum transport;

    Abstract : In this thesis, theoretical studies of the transport properties of three nanoscale systems: one-dimensional (1D) quantum wires (QWRs), zero-dimensional (0D), laterally confined, double-barrier resonant tunnelling structures (DBRTSs) and three-terminal ballistic junctions (TBJs), have been performed. In the first part of the thesis, an overview of the realization and properties of such systems is given along with a description of modelling tools used in the calculations. READ MORE

  5. 3. Synthesis and Characterization of Carbon Based One-Dimensional Structures : Tuning Physical and Chemical Properties

    Author : HamidReza Barzegar; Thomas Wågberg; Hans Kuzmany; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Carbon Nanotube; single-walled carbon nanotube; nitrogen doped; chemical vapor deposition; fullerene; hybrid structures; nanomaterials; nanomaterial;

    Abstract : Carbon nanostructures have been extensively used in different applications; ranging from electronic and optoelectronic devices to energy conversion. The interest stems from the fact that covalently bonded carbon atoms can form a wide variety of structures with zero-, one- and two-dimensional configuration with different physical properties. READ MORE

  6. 4. Families of Sets Without the Baire Property

    Author : Venuste Nyagahakwa; Vitalij Tjatyrko; Mats Aigner; Isidore Mahara; Vesko Valov; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : The family of sets with the Baire property of a topological space X, i.e., sets which differ from open sets by meager sets, has different nice properties, like being closed under countable unions and differences. On the other hand, the family of sets without the Baire property of X is, in general, not closed under finite unions and intersections. READ MORE