Browsing Research Articles (Mathematical Sciences) by Title
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Francis Guthrie : a colourful life
(Springer, 201209)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 2representations of finite groups and their 2characters
(Springer Link, 201102)Motivated by topological quantum field theory, we investigate the geometric aspects of unitary 2representations of finite groups on 2Hilbert spaces, and their 2characters. We show how the basic ideas of geometric ...

Left ventricular segmentation from MRI datasets with edge modelling conditional random fields
(BioMed Central, 201307)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
(IEEE  Institute of Electrical and Electronics Engineers, 200410)Agentoriented programming techniques seem appropriate for developing systems that operate in complex, dynamic, and unpredictable environments. We aim to address this requirement by developing modelchecking techniques for ...

Modeling HIV1 drug resistance as episodic directional selection
(PLOS Computational Biology, 201105)The evolution of substitutions conferring drug resistance to HIV1 is both episodic, occurring when patients are on antiretroviral therapy, and strongly directional, with sitespecific resistant residues increasing in ...

NonNegative Matrix Factorization for Learning AlignmentSpecific Models of Protein Evolution
(PLOS, 20111222)Models of protein evolution currently come in two flavors: generalist and specialist. Generalist models (e.g. PAM, JTT, WAG) adopt a onesizefitsall approach, where a single model is estimated from a number of different ...

On new high order quasilinearization approaches to the nonlinear model of catalytic reaction in a flat particle
(Hindawi Publishing Corporation, 2013)A novel computational approach known as pseudospectral quasilinearization (SQLM) is employed to tackle the twopoint boundary value problem describing the reactivity behaviour of porous catalyst particles subject to both ...

On the validity of evolutionary models with sitespecific parameters
(PLoS, 20140410)Evolutionary models that make use of sitespecific parameters have recently been criticized on the grounds that parameter estimates obtained under such models can be unreliable and lack theoretical guarantees of convergence. ...

An optimal proportion of mixing broadleaved forest for enhancing the effective productivity of moso bamboo
(John Wiley & Sons Ltd., 20150317)Moso bamboos (Phyllostachys edulis) are important forestry plants in southern China, with substantial roles to play in regional economic and ecological systems. Mixing broadleaved forests and moso bamboos is a common ...

Partitioning the hypercube Qn into n isomorphic edgedisjoint trees
(TU Graz University of Technology, 2011)ENGLISH ABSTRACT: The problem of finding edgedisjoint trees in a hypercube e.g. arises in the context of parallel computing. Independent of applications it is of high aesthetic appeal.

Propertybased slicing for agent verification
(Oxford University Press (OUP), 200912)Programming languages designed specifically for multiagent systems represent a new programming paradigm that has gained popularity over recent years, with some multiagent programming languages being used in increasingly ...

Realization of abstract convex geometries by point configurations
(Elsevier, 201001)The EdelmanJamison 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 EdelmanJamison problem is equivalent ...

The seesaw effect of winter temperature change on the recruitment of cotton bollworms Helicoverpa armigera through mismatched phenology
(John Wiley & Sons Ltd., 2015)Knowing how climate change affects the population dynamics of insect pests is critical for the future of integrated pest management. Rising winter temperatures from global warming can drive increases in outbreaks of some ...

Spatial assortment of mixed propagules explains the acceleration of range expansion
(Public Library of Science, 201408)Abstract Range expansion of spreading organisms has been found to follow three types: (i) linear expansion with a constant rate of spread; (ii) biphase expansion with a faster linear expansion following a slower linear ...

Special subvarieties of Drinfeld modular varieties
(Walter de Gruyter, 201011)We explore an analogue of the Andr´eOort conjecture for subvarieties of Drinfeld modular varieties. The conjecture states that a subvariety X of a Drinfeld modular variety contains a Zariskidense set of complex ...

Die SuidAfrikaanse uitgebreide maritieme gebied : ’n alternatiewe metode vir die bepaling van die voet van die kontinentale helling
(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
(Springer Verlag, 200910)Symbolic execution is a wellknown program analysis technique which represents program inputs with symbolic values instead of concrete, initialized, data and executes the program by manipulating program expressions involving ...

Thermodynamics analysis of variable viscosity hydromagnetic Couette flow in a rotating system with Hall effects
(MDPI, 20151120)In this paper, we employed both first and second laws of thermodynamics to analyze the flow and thermal decomposition in a variable viscosity Couette flow of a conducting fluid in a rotating system under the combined ...

Voorwerprekonstruksie vanaf verskeie onbeheerde sigpunte
(AOSIS Publishing, 20111027)Object reconstruction from multiple uncontrolled viewpoints. We present a featurebased approach to reconstruct unknown objects in 3D, using only a sequence of images from multiple views. The camera motion between ...

Zeta diversity as a concept and metric that unifies incidencebased biodiversity patterns
(The University of Chicago Press, 201411)Patterns in species incidence and compositional turnover are central to understanding what drives biodiversity. Here we propose zeta (ζ) diversity, the number of species shared by multiple assemblages, as a concept and ...