Now showing items 31-50 of 56

    • Identifying and modeling the dynamics of a core cancer sub-network. 

      Bayleyegn, Yibeltal Negussie. (2011)
      Many recent studies have shown that the initiation of human cancer is due to the malfunction of some genes at the R-checkpoint during the G1-to-S transition of the cell cycle. Identifying and modeling the dynamics of ...
    • Impact of exogenous reinfection on TB infection in a genetically susceptible population. 

      Mwangi, Wangari Isaac. (2013-12-17)
      In this study we investigated the impact of exogenous reinfection on genetically resistant and genetically sensitive sub populations. We qualitatively analysed the dynamics of TB by assuming that TB is transmitted in two ...
    • Matrices of graphs and designs with emphasis on their integral eigen-pair balance characteristic. 

      Jessop, Carol Lynne. (2015-01-05)
      The interplay between graphs and designs is well researched. In this dissertation we connect designs and graphs entirely through their associated matrices – the incidence matrix for designs and the adjacency matrix for ...
    • Matrix models of population theory. 

      Abdalla, Suliman Jamiel Mohamed. (2014-05-12)
      Non-negative matrices arise naturally in population models. In this thesis, we first study Perron- Frobenius theory of non-negative irreducible matrices. We use this theory to investigate the asymptotic behaviour ...
    • Modelling the response of cytotoxic t-lymphocytes in controlling solid tumour invasion. 

      Malinzi, Joseph. (2013-12-20)
      We present mathematical models to study the mechanism of interaction of tumour infiltrating cytotoxic lymphocytes (TICLs) with tumour cells. We focus on the phase spaces of the systems and the nature of the solutions for ...
    • New class of LRS spacetimes with simultaneous rotation and spatial twist. 

      Singh, Sayuri. (2016)
      In this thesis we study Locally Rotationally Symmetric (LRS) spacetimes in which there exists a unique preferred spatial direction at each point. The conventional 1+3 decomposition of spacetime is extended to a 1+1+2 ...
    • New classes of exact solutions for charged perfect fluids. 

      Mthethwa, Thulani Richard. (2014-03-28)
      We investigate techniques to generate new classes of exact solutions to the Einstein- Maxwell field equations which represent the gravitational field of charged perfect fluid spherically symmetric distributions of ...
    • New classes of exact solutions in relativistic astrophysics. 

      Matondo, Didier Kileba. (2015)
      The description of highly compact objects in a general relativistic setting is a problem of present research. The relativistic e ects arising from the presence of the electric eld and anisotropy are included in our ...
    • New realistic solutions for charged matter with an equation of state. 

      Takisa, Pedro Mafa.
      The purpose of this thesis is to provide new exact solutions to the Einstein-Maxwell system which are physically reasonable. We assume that the spacetime is static and spherically symmetric with a charged anisotropic ...
    • New solutions for nonlinear perfect fluids. 

      Nzama, Banele Jabula. (2016)
      We investigate the Einstein system that governs the evolution of uncharged shear-free spherically symmetric fluids. First we present the Einstein equations for the static spherically symmetric gravitational fields in ...
    • Nonclassical solutions of hyperbolic conservation laws. 

      Agbavon, Koffi Messan.
      This dissertation studies the nonclassical shock waves which appears as limits of certain type diffusive-dispersive regularisation to hyperbolic of conservation laws. Such shocks occur very often when the ux function ...
    • Numerical solution of the Klein-Gordon equation in an unbounded domain. 

      Lukumon, Gafari Abiodun. (2018)
      Abstract available in PDF file.
    • On Stephani universes. 

      Moopanar, Selvandren. (1992)
      In this dissertation we study conformal symmetries in the Stephani universe which is a generalisation of the Robertson-Walker models. The kinematics and dynamics of the Stephani universe are discussed. The conformal ...
    • On the integrity of domination in graphs. 

      Smithdorf, Vivienne. (1993)
      This thesis deals with an investigation of the integrity of domination in a.graph, i.e., the extent to which domination properties of a graph are preserved if the graph is altered by the deletion of vertices or edges or ...
    • On the physical viability of horizon-free collapse. 

      Ntshangase, Mlungisi Alex Doctor. (2015-09-04)
      The so-called Cosmic Censorship Conjecture has drawn widespread attention amongst astrophysicists and particle physicists. In particular, the end-state of gravitational collapse of a bounded matter distribution is a ...
    • Relativistic spherical stars. 

      Mkhwanazi, Wiseman Thokozani. (1993)
      In this thesis we study spherically symmetric spacetimes which are static with a perfect fluid source. The Einstein field equations, in a number of equivalent forms, are derived in detail. The physical properties of a ...
    • Relativistic thermodynamics of radiating stars. 

      Bogadi, Robert Sacha. (2016)
      In this research, on the topic of relativistic thermodynamics of radiating stars, the following three case studies are investigated: Gravitational collapse in spacially isotropic coordinates { The nature of a ...
    • Searching for exoplanets using the transit method. 

      Essack, Zahra. (2017)
      We present a study designed to detect transiting exoplanets in Kepler light curve data. We developed an exoplanet detection algorithm based on modelling transit light curves and fitting the models to light curve data ...
    • Shear-free models for relativistic fluids with heat flow and pressure isotropy. 

      Brassel, Byron P. (2014)
      We model the interior dynamics of a relativistic radiating fuid in a nonstatic spher- ically symmetric spacetime. The matter distribution takes the form of an imperfect fuid with a nonvanishing radially directed heat ...
    • Solution generating algorithms in general relativity. 

      Krupanandan, Daniel D. (2011)
      We conduct a comprehensive investigative review of solution generating algorithms for the Einstein field equations governing the gravitational behaviour of an isolated neutral static spherical distribution of perfect ...