Browsing School Mathematics, Statistics and Computer Science by Title
Now showing items 148167 of 225

Neural network assisted software engineered refractive fringe diagnostic of spherical shocks.
(1996)A shock is essentially a propagating variation in the pressure or density of a medium. If the medium is transparent, such as air, and the shock radially symmetric, the refractive fringe diagnostic can be used to examine ... 
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 ... 
Noether's theorem and first integrals of ordinary differential equations.
(1997)The Lie theory of extended groups is a practical tool in the analysis of differential equations, particularly in the construction of solutions. A formalism of the Lie theory is given and contrasted with Noether's theorem ... 
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 ... 
Nonlinear mixedeffects models for multivariate longitudinal data with application to HIV disease dynamics.
(2014)The motivation for the study of nonlinear mixedeffects models is due to the growing interest in the estimation of parameters in HIV disease dynamical models using real multivariate longitudinal data with varying degrees ... 
Nonlinear models for neural networks.
(2000)The most commonly used applications of hiddenlayer feed forward neural networks are to fit curves to regression data or to provide a surface from which a classification rule can be found. From a statistical viewpoint, the ... 
On case representation and indexing in a casebased reasoning system for waste management.
(1997)CaseBased Reasoning is a fairly new Artificial Intelligence technique which makes use of past experience as the basis for solving new problems. Typically, a casebased reasoning system stores actual past problems and ... 
On convection and flow in porous media with crossdiffusion.
(2012)In this thesis we studied convection and crossdiffusion effects in porous media. Fluid flow in different flow geometries was investigated and the equations for momentum, heat and mass transfer transformed into a system ... 
On free convection and heat transfer in a micropolar fluid flow past a moving semiinfinite plate.
(2012)In this dissertation we investigate free convective heat and mass transfer in micropolar fluid flow past a moving semiinfinite vertical porous plate in the presence of a magnetic field. The aim of this study was to use ... 

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 ... 
On the theory and examples of group extensions.
(1999)The work described in this dissertation was largely motivated by the aim of producing a survey on the theory of group extensions. From the broad scope of the theory of group extensions we single out two aspects to discuss, ... 
On the theory of the frobenius groups.
(2012)The Frobenius group is an example of a split extension. In this dissertation we study and describe the properties and structure of the group. We also describe the properties and structure of the kernel and complement, ...