Browsing Applied Mathematics by Title
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Matrices of graphs and designs with emphasis on their integral eigenpair balance characteristic.
(20150105)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.
(20140512)Nonnegative matrices arise naturally in population models. In this thesis, we first study Perron Frobenius theory of nonnegative irreducible matrices. We use this theory to investigate the asymptotic behaviour ... 
A modelling approach for determining the freshwater requirements of estuarine macrophytes.
(1998)Increased abstraction of water in the catchment results in a reduced or altered pattern of river flow and this holds serious consequences for the downstream estuarine ecosystem. In South Africa this is a serious concern ... 
Modelling the response of cytotoxic tlymphocytes in controlling solid tumour invasion.
(20131220)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 ... 
Modelling waterborne diseases.
(20150320)Waterborne diseases are among the major health problems threatening the life of individuals globally. This thesis investigates the dynamics of waterborne disease under different conditions and consequently determines ... 
Models in isotropic coordinates with equation of state.
(20150904)In this thesis we consider spacetimes which are static and spherically symmetric related to the Einstein and EinsteinMaxwell system of equations in isotropic coordinates. We study both neutral and charged matter ... 
New classes of exact solutions for charged perfect fluids.
(20140328)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 models for quark stars with charge and anisotropy.
(2014)We find new classes of exact solutions for the EinsteinMaxwell field equations. The solutions are obtained by considering charged anisotropic matter with a linear equation of state consistent with quark stars. The field ... 
New realistic solutions for charged matter with an equation of state.
The purpose of this thesis is to provide new exact solutions to the EinsteinMaxwell system which are physically reasonable. We assume that the spacetime is static and spherically symmetric with a charged anisotropic ... 
Noncircularity of beams in the CMB polarization power spectrum estimation.
(20150105)Precise measurements of the Cosmic Microwave Background (CMB) anisotropies have been one of the foremost concerns in modern cosmology as it provides valuable information on the cosmology of the Universe. However, an ... 
Nonclassical solutions of hyperbolic conservation laws.
This dissertation studies the nonclassical shock waves which appears as limits of certain type diffusivedispersive regularisation to hyperbolic of conservation laws. Such shocks occur very often when the ux function ... 
On new and improved seminumerical techniques for solving nonlinear fluid flow problems.
(2012)Most real world phenomena is modeled by ordinary and/or partial differential equations. Most of these equations are highly nonlinear and exact solutions are not always possible. Exact solutions always give a good account ... 
On singularly perturbed problems and exchange of stabilities.
(2015)Singular perturbation theory has been used for about a century to describe models displaying different timescales, that arise in applied sciences; particularly, models displaying two timescales, namely slow time and fast ... 
On Stephani universes.
(1992)In this dissertation we study conformal symmetries in the Stephani universe which is a generalisation of the RobertsonWalker models. The kinematics and dynamics of the Stephani universe are discussed. The conformal ... 
On the integrity of domination in graphs.
(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 horizonfree collapse.
(20150904)The socalled Cosmic Censorship Conjecture has drawn widespread attention amongst astrophysicists and particle physicists. In particular, the endstate of gravitational collapse of a bounded matter distribution is a ... 
Optimisation of the population Monte Carlo algorithm : application to cosmology.
(20150904)In this thesis we study the Population Monte Carlo (PMC) algorithm and utilise simulations to improve the efficiency of the algorithm by optimising the algorithm parameters. We then ap ply these optimisation results to ... 
Partial exchangeability and related topics.
(1991)Partial exchangeability is the fundamental building block in the subjective approach to the probability of multitype sequences which replaces the independence concept of the objective theory. The aim of this thesis is ... 
Relativistic spherical stars.
(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 ... 
Shearfree models for relativistic fluids with heat flow and pressure isotropy.
(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 ...