Now showing items 9-21 of 21

  • Francis Guthrie : a colourful life 

    Maritz, Pieter; Mouton, Sonja (Springer, 2012-09)
    In 1852, in London, Francis Guthrie posed the question of colouring a map with four colours only, the question that eventually became known as the Four Colour Problem. The problem is famous, but what else do we know of ...
  • The geometry of unitary 2-representations of finite groups and their 2-characters 

    Bartlett, Bruce (Springer Link, 2011-02)
    Motivated by topological quantum field theory, we investigate the geometric aspects of unitary 2-representations of finite groups on 2-Hilbert spaces, and their 2-characters. We show how the basic ideas of geometric ...
  • Left ventricular segmentation from MRI datasets with edge modelling conditional random fields 

    Dreijer, Janto F.; Herbst, Ben M.; Du Preez, Johan A. (BioMed Central, 2013-07)
    Background: This paper considers automatic segmentation of the left cardiac ventricle in short axis magnetic resonance images. Various aspects, such as the presence of papillary muscles near the endocardium border, makes ...
  • Model checking rational agents 

    Bordini, Rafael H.; Fisher, Michael; Wooldridge, Michael; Visser, Willem (IEEE - -Institute of Electrical and Electronics Engineers, 2004-10)
    Agent-oriented programming techniques seem appropriate for developing systems that operate in complex, dynamic, and unpredictable environments. We aim to address this requirement by developing model-checking techniques for ...
  • Modeling HIV-1 drug resistance as episodic directional selection 

    Murrell, Ben; De Oliveira, Tulio; Seebregts, Chris; Pond, Sergei L. Kosakovsky; Scheffler, Konrad (PLOS Computational Biology, 2011-05)
    The evolution of substitutions conferring drug resistance to HIV-1 is both episodic, occurring when patients are on antiretroviral therapy, and strongly directional, with site-specific resistant residues increasing in ...
  • Non-Negative Matrix Factorization for Learning Alignment-Specific Models of Protein Evolution 

    Murrell, Ben; Weighill, Thomas; Buys, Jan; Ketteringham, Robert; Moola, Sasha; Benade, Gerdus; du Buisson, Lise; Kaliski, Daniel; Hands, Tristan; Scheffler, Konrad (PLOS, 2011-12-22)
    Models of protein evolution currently come in two flavors: generalist and specialist. Generalist models (e.g. PAM, JTT, WAG) adopt a one-size-fits-all approach, where a single model is estimated from a number of different ...
  • Partitioning the hypercube Qn into n isomorphic edge-disjoint trees 

    Wagner, Stephan; Wild, Marcel (TU Graz University of Technology, 2011)
    ENGLISH ABSTRACT: The problem of finding edge-disjoint trees in a hypercube e.g. arises in the context of parallel computing. Independent of applications it is of high aesthetic appeal.
  • Property-based slicing for agent verification 

    Bordini, Rafael H.; Fisher, Michael; Wooldridge, Michael; Visser, Willem (Oxford University Press (OUP), 2009-12)
    Programming languages designed specifically for multi-agent systems represent a new programming paradigm that has gained popularity over recent years, with some multi-agent programming languages being used in increasingly ...
  • Realization of abstract convex geometries by point configurations 

    Adaricheva, Kira; Wild, Marcel (Elsevier, 2010-01)
    The Edelman-Jamison problem is to characterize those abstract convex geometries that are representable by a set of points in the plane. We show that some natural modification of the Edelman-Jamison problem is equivalent ...
  • Spatial assortment of mixed propagules explains the acceleration of range expansion 

    Ramanantoanina, Andriamihaja; Ouhinou, Aziz; Hui, Cang (Public Library of Science, 2014-08)
    Abstract Range expansion of spreading organisms has been found to follow three types: (i) linear expansion with a constant rate of spread; (ii) bi-phase expansion with a faster linear expansion following a slower linear ...
  • Special subvarieties of Drinfeld modular varieties 

    Breuer, Florian (Walter de Gruyter, 2010-11)
    We explore an analogue of the Andr´e-Oort conjecture for subvarieties of Drinfeld modular varieties. The conjecture states that a subvariety X of a Drinfeld modular variety contains a Zariski-dense set of complex ...
  • Die Suid-Afrikaanse uitgebreide maritieme gebied : ’n alternatiewe metode vir die bepaling van die voet van die kontinentale helling 

    Pantland, N. A.; Van Vuuren, J. H. (AOSIS OpenJournal, 2006)
    Kuslande het ’n eenmalige geleentheid om by die Verenigde Nasies (VN) aansoek te doen om ’n uitgebreide maritieme gebied, indien hul wetenskaplik kan toon dat die voet van die kontinentale helling (VKH) buite hul soewereine ...
  • A survey of new trends in symbolic execution for software testing and analysis 

    Pasareanu, Corina S.; Visser, Willem (Springer Verlag, 2009-10)
    Symbolic execution is a well-known program analysis technique which represents program inputs with symbolic values instead of concrete, initialized, data and executes the program by manipulating program expressions involving ...