Sökning: "symmetry exploiting"

Visar resultat 1 - 5 av 13 avhandlingar innehållade orden symmetry exploiting.

1. 1. Exploiting reciprocal space : Electron diffraction, textures and precession

   Författare :Peter Oleynikov; Sven Hovmöller; Xiaodong Zou; Jean-Paul Morniroli; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; electron crystallography; electron diffraction; texture patterns; precession electron diffraction; Inorganic chemistry; Oorganisk kemi;

   Sammanfattning : Electron crystallography emerges as a new tool for accurate structure determination of very small crystals. In order to exploit the full potential of electron diffraction, the methods for data acquisition and processing have to be developed towards the high standards of X-ray crystallography. LÄS MER

3. 2. Design of High Performance Computing Software for Genericity and Variability

   Författare :Malin Ljungberg; Michael Thuné; Kurt Otto; Hans Petter Langtangen; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; PDE solver; high-performance; coordinate invariant; curvilinear coordinates; symmetry exploiting; generalized Fourier transform; finite difference; expression templates; feature modeling; variability; Beräkningsvetenskap; Scientific Computing;

   Sammanfattning : Computer simulations have emerged as a cost efficient complement to laboratory experiments, as computers have become increasingly powerful. The aim of the present work is to explore the ideas of some state of the art software development practices, and ways in which these can be useful for developing high performance research codes. LÄS MER

4. 3. On Symmetries and Metrics in Geometric Inference

   Författare :Giovanni Luca Marchetti; Danica Kragic; Anastasiia Varava; Emanuele Rodolà; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Machine Learning; Computational Geometry; Voronoi; Delaunay; Symmetry; Equivariance; Datalogi; Computer Science;

   Sammanfattning : Spaces of data naturally carry intrinsic geometry. Statistics and machine learning can leverage on this rich structure in order to achieve efficiency and semantic generalization. Extracting geometry from data is therefore a fundamental challenge which by itself defines a statistical, computational and unsupervised learning problem. LÄS MER

5. 4. Wirelessly Powered Communications: From Signal Optimization to Antenna Design

   Författare :Boules Atef Nessim Mouris; Ragnar Thobaben; Aggelos Bletsas; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wireless power transfer; multi-tone signals; non-linear energy harvester; wirelessly powered sensors; joint source-channel coding; analog mappings; energy scheduling; mutual coupling reduction; electromagnetic bandgap; glide symmetry.; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : Future internet-of-things (IoT) and beyond 5G communication systems are envisioned to offer large-scale wireless connectivity where the different components of life, society and industry are connected in a smart yet sustainable way. The need for continuous battery charging and/or replacement is a bottleneck for sustainability in these systems. LÄS MER

7. 5. Defects, renormalization and conformal field theory

   Författare :Alexander Söderberg Rousu; Agnese Bissi; Pedro Liendo; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; defects; boundaries; replica twist defect; conformal field theory; quantum field theory; Coleman-Weinberg mechanism; renormalization group flows; Theoretical Physics; Teoretisk fysik;

   Sammanfattning : Defects in quantum field theories appear in many different contexts and are of great physical interest. Among other things, defects are used to describe the Kondō effect in condensed matter, confinement in quantum chromodynamics, Rényi entropy in quantum information and cosmic strings in string theory. LÄS MER