Turnaround time of a vessel in a seaport exhibits the capability and ability of a port in providing efficient and effective services. Ship turnaround time is one of the most significant Port performance indicator. This is the total time, spent by the vessel in port, during a given call. It is the sum of waiting time, berthing time, service time (i.e., ship’s time at berth) and sailing delay. West African ports play a crucial role in trade and economy, as 95% of merchandise trade is handled ...
Abstract/Overview Differential equations have been used to create mathematical models of real world systems in which rates of change are involved, for example in the study of how population grows or shrinks. One of the earliest models by Thomas Malthus has been found to be unrealistic since it predicts that population will grow exponentially and without bound – a prospect that defies physical limitations. Verhulst in his logistic population model developed a generalized version of the M...
Abstract/Overview We formulate a deterministic mathematical model for the HIV/AIDS.
Abstract/Overview Pneumonia occurs commonly in HIV-infected patients. In this paper, we study a simple mathematical model for the co-infection of HIV/AIDS and Pneumonia. We establish that the model is well presented epidemiologically and mathematically. The disease-free equilibrium point is determined. We establish the basic reproduction number R0 for the model, which is a measure of the course of co-infection.
Abstract/Overview The present study addresses the problem of minimum cost and precision in the estimation of the population mean in the presence of nonresponse and measurement errors. It is assumed that both the survey variable and the auxiliary variable suffer from nonresponse and measurement errors in the second phase sample. A ratio, exponential ratio-ratio type, and exponential product-ratio type estimators of the population mean are proposed using the information on a single auxiliar...
Abstract/Overview Volatility is the measure of how we are uncertain about the future of stock or asset prices. Black-Scholes model formed the foundation of stock or asset pricing. However, some of its assumptions like constant volatility and interest among others are practically impossible to implement hence other option pricing models have been explored to help come up with a much reliable way of predicting the price trends of options. The measure of volatility and good forecasts of futu...
Abstract/Overview In this paper, a nonlinear fourth order evolution equation is investigated by the Lie symmetry analysis approach. All the geometric vector fields and the Lie groups of the evolution equation are obtained. Finally, the symmetry reduction and the exact solutions of the equation are obtained by means of power series method.
Abstract/Overview In modern financial mathematics, accurate values are obtained by taking into account a considerable number of more realistic assumptions in logistic Black Scholes equation. The aspects considered here are cost of transactions in trading, perfect illiquid markets and risks that occur from non – protected portfolio or large investments that have a lot of impact on price of the assets, volatility, the percentage drift and the life of the portfolio itself. In modern world ...
Abstract/Overview In this paper, we have characterized big data fuzzy sets and shown that topological data points form singleton fuzzy sets which are closed. Besides, fuzzy sets of topological data points are compact and have at least one closed point. We have also shown that the fuzzy set of all condensation points of a fuzzy Hausdorff space is infinite and the cardinality of a topological data fuzzy set is also infinite and arbitrarily distributed in fuzzy Hausdorff spaces.
Abstract/Overview Modeling of invasive species using stage based matrix methods can be exploited to understand population dynamics of plants using stage based Leftkovitch matrix models. This study reviewed and extended the stage based matrix incorporating invasion variables of invasive Cestrum aurantiacum across different forest types, ecological zones and altitudes. The estimation of eigenvalues of the extended stage based Lefkovitch matrix and its corresponding right and left eigenvecto...
Abstract/Overview This study analyzes recent data of accidents’ prevalence in Kenya and investigates whether there might be new trends in areas formerly not prone to accidents. Polynomials of order 6 are found best suited for accidents’ prevalence data. The graphs show that seasonal variations explain over 90% of prevalence in Central, Eastern, Nyanza, Rift-Valley and Western Provinces. The highest variation is in Nyanza with 98.54% of the prevalence rate explained by the seasonal var...
Abstract Pension valuation exercises for a defined benefit scheme requires an appraisal of both the schemes assets and its liabilities in different circumstances. The valuations are required to comply with regulatory standards, most notably the minimum funding standard. The objectives of this study are: (i) to compute the estimate of minimum funding standard of pension liability (ii) to establish the actuari...
Accurate collection of wind speed records is significant for numerous wind power applications. The present investigation aims to highlight the use of the Marshall–Olkin Power Lomax (MOPLx) distribution for wind speed data. We examine the actual wind speed records gathered from three stations Bahawalpur, Gwadar, and Haripur. The dataset is demonstrated by using MOPLx distribution and compare its modeling performance with renowned probability distributions, for example, Weibull– Lomax, powe...
Pension, being regular payments made to retirees or their beneficiaries after retiring from active service, needs efficient and effective management because of the funds involved as the living standard of the retirees and their dependants rest on it after retirement. In attempt to maximize the wealth of pension contributors, the investors may end up losing the pension fund assets because higher returns on investment go hand in hand with higher risk of loss of invested contributions/savings. T...
A REVIEW OF MORTALITY DIFFERENTIALS. Abere, OmotayoJohncally([email protected]) Department of Actuarial Science & Insurance, University of Lagos Nigeria Mojekwu, Joseph Nnamdi (Corresponding Author) Department of Actuarial Science & Insurance, University of Lagos Nigeria E-mail: [email protected] Abstract. Introduction: Mortality differentials can be described as those determinants or indicators that measure relative differences in the timing of death between different groups. They m...