Abstract We find two new classes of exact solutions for the Einstein-Maxwell equations. The solutions are obtained by considering charged anisotropic matter with a linear equation of state consistent with quark stars. The field equations are integrated by specifying forms for the measure of anisotropy and a gravitational potential which are physically reasonable. The solutions found generalize the Mark-Harko model and the Komathiraj-Maharaj model. A graphical analysis indicates that th...

Abstract We find new exact solutions to the Einstein-Maxwell field equation for charged anisotropy stellar bodies. We are considering the stellar object that is anisotropic and charged with linear equation of state consistent with quark stars. We have new choice of measure of anisotropy and adopted Sunzu’s metric function. The solutions are obtained after considering the transformed Einstein-Maxwell field equations for charged anisotropic matter. In our models we regain previous aniso...

ABSTRACT Manifolds are generalization of curves and surfaces to arbitrary higher dimensions. They are of many kinds, one of them being topological manifolds. The main feature common to manifolds is that every point of the space is in one to one correspondence with a point in another space. Hausdorff manifolds have been developed on infinite dimensional spaces such as Banach spaces and Fréchet spaces. Topological properties of non-Hausdorff manifolds have been studied and the notion of ...

ABSTRACT A category is defined as an algebraic structure that has objects that are linked by morphisms. Categories were created as a foundation of mathematics and as a way of relating algebraic structures and systems of topological spaces. Any foundation of mathematics must include algebra, topology, and analysis. Algebra and topology have been studied extensively in category theory but not the analysis. This is partly due to the algebraic nature of category theory and the fact that the...

AbstractThis thesis consists of two chapters, of which thefirst presents a categorial study of the concept ofinitiality (also known as projective generation) and thesecond gives applications in the.theory of uniform andquasi-uniform spaces,The' first three sections of chapter 1 expound basicaspects of initiality, such as its relation to categoriallimits and to embeddings, the· latter being defined withrespect to a faithful functor to a bicategory. The notionof a separated object with re...

Abstract Due to the 2008 financial crisis, investors have become more risk averse in investing in equities and have increased their holdings in bonds as they are believed to be less risky. However, South African interest rates have been volatile over the past decade due to changes in the inflation rate. This has caused the returns of bond portfolios to be uncertain since bond prices are inversely related to interest rates. It is thus imperative to manage the interest rate risk inherent...

ABSTRACTThe dynamic buckling loads of some imperfection-sensitive elastic structures subjectedto slowly varying time dependent loading are determined using perturbation procedures.First, we consider an elastically imperfect column resting on a softening nonlinear elasticfoundation. The governing differential equation has two small parameters. We determinethe dynamic buckling load of this column subjected to the stipulated loading for threedifferent cases. The cases are when the small pa...

ABSTRACTLet H be a real Hilbert space and K a nonempty, closed and convex subset of H. LetT : K ! K be an asymptotically nonexpansive map with a nonempty xed points set.Let fng1n=1 and ftng1 n=1 be real sequences in (0,1). Let fxng be a sequence generatedfrom an arbitrary x0 2 K byyn = PK[(1 tn)xn]; n 0xn+1 = (1 n)yn + nTnyn; n 0:where PK : H ! K is the metric projection. Under some appropriate mild conditionson fng1n=1 and ftng1 n=1, we prove that fxng converges strongly ...

ABSTRACTIn this theses, we investigate certain key aspects of mathematical modelling to explain theepidemiology of HIV/AIDS, Tuberculosis, Hepatitis B, Tumour,diabetes and stroke at theworkplace and assess the potential benefits of proposed control strategies. The compartmentalepidemiological modelling approach was used in the formulation of the models on HIV/AIDS,tuberculosis (TB), Hepatitis B (HBv), Tumour and Diabetes pandemic. In each of the cases, the dynamicsof the disease was stud...

AbstractMathematical study of human pulse wave was studied with the view to gaining an insight intophysiological situations. Fluid –Structure interaction (FSI) in blood flow is associated withpressure pulse wave arising from ventricular ejection. Solution of the coupled system of nonlinearPDEs that arose from the FSI was sought in order to determine pressure. Further study onpressure pulse waves showed that the Korteweg-de Vries (KdV) equations hold well for thepropagation of nonlinear...

AbstractIn recent years, advance in technology have made it possible for the stock marketsto trade in real time and also for large dataset to be available for statistical analysis.Thus, we examined the impact of macroeconomic variables on the stock returns of114 companies listed on the Nigerian Stock Exchange Market. We have establishedthe mathematical framework required to solve our model and perform various empir-ical analysis on the stock market data and macroeconomic variable. The f...

Abstract In this paper, we apply the LINEST model of the Microsoft excel to the population, Nigeria (Naira) exchange rate with US Dollar and Internal Generated Revenue (IGR) of 2014 top-10 Nigerian states by IGR in billions of naira from 2010 to 2014 as in the data bases of National Population Commission (NPC), Central Bank of Nigeria (CBN) and National Bureau of Statistics (NBS) respectively. The indexed IGR is used as proxy for each state and the nation. The last c...

The study was conducted on the topic: Minimizing the Probability of Ultimate Ruin by Proportional Reinsurance and Investments. The purpose of the study was to determine the role of investments in minimizing the probability of ultimate ruin of an insurance company, to assess the impact of proportional reinsurance on the survival of insurance companies as well as to determine the optimal reinsurance percentage b ∈ (0, 1].The study considered a risk process comprising ...

We study the operator commuting and essential commutant of analytic Toeplitz operators module the compact operators and Toeplitz operators in several complex variables and on the Bergman space of the until ball. We show the ordered groups and some exact sequences and the commutator ideal of the Toeplitz algebras of spherical isometries and on the Bergman spaces of the unit ball in the unitary space. We give the lower bounds in the matrix, new estimate for the vec...

In this work we discuss the scope of Lagrangian mechanics and constrained systems. We discuss the problem of central force two–bodies and its formal solution. Also we study the rotations and rigid bodies by using Euler’s equations, Lagrangian description and Legender transformations with some examples and applications.