Sökning: "Voronoi tessellation"

Hittade 5 avhandlingar innehållade orden Voronoi tessellation.

  1. 1. Voronoi-Based Coding

    Författare :Erik Agrell; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Voronoi diagram; linear block code; Gaussian channel; neighbor descent; nearest neighbor search algorithm; computational geometry; asymptotic theory; source coding; lattice; vector quantization; soft-decision decoding; index assignment; channel coding; complexity;

    Sammanfattning : The performance of a digital communication system can generally be improved by increasing the number of variables being jointly coded. In this sense, it is desirable to have, e.g., higher-dimensional quantizers, longer channel codes, and more users in a multiple-access system. LÄS MER

  3. 2. Non-overlapping Germ-grain Models: Characteristics and Material Modelling

    Författare :Jenny Andersson; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Poisson process; Convex sets; Material fatigue; Voronoi tessellation; Germ-grain process; Pair-correlation function; Mark-correlation function; Short cracks; Volume fraction; Germ-grain process;

    Sammanfattning : We consider three different non--overlapping germ--grain models, two of which are constructed in a similar fashion. These two models are generalisations of Mat\'ern's hard--core models. In both cases we start with a homogeneous Poisson process and use the points as centres of convex sets, grains, of the same shape. LÄS MER

  4. 3. Metal Hydrogen Interaction and Structural Characterization of Amorphous Materials from first principles

    Författare :Robert Johansson; Ralph Scheicher; Olle Eriksson; Rajeev Ahuja; Peter Mohn; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; hydrogen; vanadium; zintl; laves; strain; diffusion; amorphous; dft; molecular dynamics; md; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : In this thesis, first-principles calculations based on density functional theory have been employed to investigate metal hydrogen interaction in transition, p-block and rare earth metals. Furthermore, the accuracy of the stochastic quenching method was tested in describing the structure of amorphous Fe(1-x)Zrx. LÄS MER

  5. 4. Deriving effective forces for mesoscopic particle simulations

    Författare :Johan Nyström; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Coarse graining; Boids; Force covariance; Mori-Zwanzig projection; Dissipative particle dynamics; Force matching; Flocking.;

    Sammanfattning : In the field of molecular simulations, the long-standing aim has been to study mechanisms that cannot easily be observed in experiments or understood in terms of more abstract models. This is hard for systems of mesoscopic size (proteins, membranes etc. LÄS MER

  7. 5. Mechanical optimization of orthopaedic bone screw constructs

    Författare :Yijun Zhou; Cecilia Persson; Benedikt Helgason; Philip Procter; Richie Gill; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Trabecular bone; screw implant; explicit finite element modelling; computed tomography; numerical optimization; neural network; hydrogel; Engineering Science with specialization in Biomedical Engineering; Teknisk fysik med inriktning mot medicinsk teknik;

    Sammanfattning : Orthopaedic screw implants are crucial in surgical procedures for bone structures, with a longstanding issue being screw loosening. Improving screw stability requires an enhanced understanding of the bone-implant interactions and associated failure mechanisms. This knowledge can be used to optimize screw designs. LÄS MER