| 1 |
Author(s):
Edike Nnamdi, Agbedeyi Odimientimi Desmond.
Page No : 1-10
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Monitoring the Reproduction Number and Stringency Index of Covid-19 Pandemic in Nigeria.
Abstract
In order to track the Covid-19 pandemic's reproduction number and stringency index in Nigeria, this research presents the implementation of control chart approaches. This will assist in monitoring these pertinent parameters and assist decision-makers in determining whether to impose stricter or less strict containment measures to stop the spread of a disease. The data for this study data was sourced from the Our World In Data (OWID) website (https://www.owid.org). This database contains information about how the Covid-19 pandemic has spread globally. The data consist of the reproduction number and the stringency index of the pandemic from February 2020 to July 2022. The range chart was used to monitor the variability in these indices. The findings indicate that during the first 42 days of infection, the pandemic's reproduction number and stringency index are not within statistically significant ranges, hence out of statistical control. This could explain the virus's quick spread as well as the nation's economy's suffering due to harsh government measures. The study concludes, therefore, that statistical quality control charts are a viable option for tracking a few key pandemic metrics. This would assist in educating interested parties about the necessity of taking the necessary actions to stop the spread of such a pandemic.
| 2 |
Author(s):
Jackson Ante , Okoi Itam , Jeremiah Atsu , Samuel Essang , Etimbuk Abraham , Michael Ineh .
Page No : 11-33
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On the Novel Auxiliary Lyapunov Function and Uniform Asymptotic Practical Stability of Nonlinear Impulsive Caputo Fractional Differential Equations via New Modelled Generalized Dini Derivative.
Abstract
In this paper, the uniform asymptotic practical stability of nonlinear impulsive Caputo fractional differential equations with fixed moment of impulse is examined using an auxilliary Lyapunov functions which are analogues of vector Lyapunov functions. Together with comparison results, sufficient conditions for the uniform practical stability as well as the uniform asymptotic practical stability of the impulsive Caputo fractional order systems are established. An illustrative example is given to confirm the suitability of the obtained results.
| 3 |
Author(s):
Ishola Sakirudeen Akinola (Ph.D.).
Page No : 34-56
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Groundwater Quality Assessment using Descriptive and Associated Statistical Analyses in Itori District of Ogun State, South-West Nigeria.
Abstract
Groundwater is a natural gift whose significance in all spheres of human endeavours cannot be underestimated. It also plays a critical role and indispensable contribution in the dilution and intake of a number of several nutritional and toxic trace elements in the body system of humans and other biological populations. This study has examined the concentration status of heavy metals in wells and boreholes of Wasinmi within Ewekoro Local Government Area of Ogun State, South-West Nigeria. The existing and functioning 25 boreholes and 25 hand-dug wells in the area were physically and chemically sampled using Ion Chromatography (IC) for anions, Nitrate, Phosphates, Bicarbonate, Chloride and Sulphate were measured after chromatography separation utilizing conductivity detectors while Inductively Coupled Mass Spectrometer (ICP-MS) and Inductively Coupled Optical Emission Spectrometry (ICP-OES) were used for heavy metals and trace elements detection. The raw data obtained from the laboratory analyses were subjected to statistical treatment using SPSS software version 20.0. Results of the analyses revealed that the concentrations of Copper (Cu), Lead (Pb), Zinc (Zn), and Manganese (Mn) were within approved guidelines including WHO and NESREA maximum permissible limits with mean values of 0.020.01mg/L and 0.040.02mg/L; 0.0040.0005mg/L and 0.00080.0004mg/L; 1.0080.37mg/L and 1.600.89 mg/L and 0.010.009mg/L and 0.040.01mg/L, respectively for boreholes and wells. The proportion of Cadmium (Cd) was also very low, with a mean concentration value of 0.00020.0004mg/L and 0.00070.0005mg/L for boreholes and wells respectively. The value of chromium and cobalt were found to be significantly low (0.00010.0003mg/L) in boreholes only and largely undetected in wells while Iron exhibited elevated concentration mean values of 0.440.34mg/L and 0.540.32mg/L respectively for boreholes and wells which is above the permissible water quality set standards. The elevated values of the identified parameters notably DO, BOD, Alkalinity, Cl−, HCO3−, Zn2+, and Fe3+ in the groundwater system of the study area that were above the set standards are major concern to the health of the consumers which necessitates a proactive response from the communities.
| 4 |
Author(s):
E. E. Chinwuba, Okafor Patrick Nnaemeka, Kama Henry Nnanna.
Page No : 57-71
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Using Improved Two-Source Capture-Recapture Methods In Settling Disputed Election Results.
Abstract
Introduction of new technology to check rigging and manipulation of election results by the Independent National Electoral Commission (INEC) raised hopes and dreams of many Nigerians, especially the new electorates, that the 2023 general election in Nigeria would be free and fair. Cross-checking INEC declared election results using this recapture model is supposed go beyond questionnaires. Sampling technique to select polling units where re-run election is to take place is necessary. They have been issues of vote suppression, rigging, manipulation or intimation in those areas would have largely been reduced. The new estimator has shown that there were no serious cases of vote suppression, manipulation or intimation by any political party, as far as this Local Government Area is concerned. If there were vote suppression, it is only about 1.78% which is negligible. Using simulated data, we found that efficient recapture model (Me) provides better and more reliable estimate than the conventional models.
| 5 |
Author(s):
Ishola Sakirudeen Akinola (Ph.D.)..
Page No : 57-81
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Evaluations of Groundwater Quality using Principal Component Analysis and Associated Multivariate Techniques: A Case History in Ewekoro Communities, South-West Nigeria.
Abstract
The quest for quality water consumption is comprised of integration of numerous techniques from different professionals whose contributions go a long way in determining overall health status and wellness of any given society. The water quality status of boreholes in Ewekoro communities of Ewekoro Local Government Area, South-West Nigeria was investigated in this work. Water samples were collected from 25 boreholes at various sampling stations across the study area. Standard analytical water quality methods using Inductively Coupled Mass Spectrometry (ICP-MS)/Optical Emission Spectrometry (ICP-OES) and Pour Plate Techniques were respectively employed in the laboratory for the samples’ geochemical and bacteriological analyses. The raw data were processed and analyzed using Principal Component Analysis and other multivariate techniques with Excel and SPSS 20.0 statistical software packages with the corresponding outcomes systematically compared with water quality standards. For the PCA, the varimax rotation converged in 23 iterations with 6 components extracted which accounted for 92.76% of the total cumulative variance respectively observed for geochemical parameters. Na2+, K+, Ca2+, Cl-, SO42-, NH4+, PO43-, and HCO3-, Mg3+, Cu2+, Cd2+, Zn2+, Ni, S , Si, Fe3+, NO3− and Al3+ played a significant contribution with higher factor loading supported by the dominance of HCO3− among the water quality determinants. The rotation converged in 8 iterations with 3 extracted components that accounted for a total cumulative variance of 90.99% % with pH, TEMP, EC, BOD, TS, TURB, ALK, TH, TDS, THC, and DO in the Physico-chemical Parameters series. Most quality determinants in the sampled water are within allowable limits of the approved water quality standards including WHO except Alkalinity, HCO3−, MgCO3−, Cl−, BOD, Cd2+, Fe3+ and Zn2+. The overall ionic dominance pattern follows the same trend K+ >Na2+ > Fe3+ >Mn2+ and Cl- >NO3- >NO2-. The results of the microbial analyses revealed the highest Total Coliform Count of 17 x 102 MPN/100 ml while that of THBC and FCC were reported as 7.8 ×102 cfu/ml and 1.2×102 cfu/ml respectively. The hygienic status of the water sources was found to be poor. High BOD, Coliform Count and BOD5:NO3- ratios of 248.23 recorded for the groundwater samples were suggestive of possible organic pollution due to faecal invasion with the lowest measured depth of 35m. Multivariate statistical approaches namely Correlation, Principal Component Analysis and Descriptive statistics simplified and identified the interrelationship among the analyzed physicochemical parameters and the pollution sources. This study has therefore revealed that boreholes in Ewekoro were polluted and posed potential risk to biomedical safety and overall human health. Intervention measures are therefore necessary to safeguard the inhabitants from water-related diseases and their consequences.
| 6 |
Author(s):
Adamu Danbaba , Jelten B Naphthali, Momoh U. Sunday.
Page No : 82-86
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Construction of Finite 2-Transitive Groups Based on the Concept of Near Field.
Abstract
Transitive groups were studied basically based on the idea of near field. The article mainly considered Dickson near field to construct groups which are 2-transitive..To achieve the result some restrictions were observed in relation to the near field. The research went through the constructions with the help of the classification scheme for finite primitive groups proposing that the subgroup is the stabilizer of the group. The idea of this constructions has relevance in coding theory.
| 7 |
Author(s):
Godwin Ojemeri , A. S. Ibrahim, I. O. Onwubuya.
Page No : 87-104
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Mixed Convection Flow of a Viscous Dissipative and Heat Generating/Absorbing Fluid Through a Slit Microchannel.
Abstract
This paper is aimed at investigating the consequences of viscous dissipation and super-hydrophobicity on a magnetized mixed convection flow of an electrically conducting fluid across an up facing microchannel influenced by a transverse magnetic field. The plates were alternatively heated and incorporated with heat source/sink effect. The modeled governing equations have been obtained using a semi-analytical (regular perturbation) method. Various line graphs have been plotted to demonstrate the behavior of key parameter dictating the flow. It is found out that the thermal gradient and fluid velocity are significantly enhanced for mounting values of mixed convection , Brickman number , Darcy porous number and heat source parameters in the superhydrophobic microchannel for constant pressure gradient . On the other hand, the velocity deteriorates for increasing levels of magnetic field and heat sink factors. Further, the comparison of this present analysis with previously published literature for limiting cases when and showcased an excellent concurrence, thereby confirming the accuracy and validity of this present investigation. The findings from this research will find relevance in engineering, technological and industrial processes such as for solar collectors, nuclear reactors cooled during emergency shutdown, Nuclear power plants, gas turbines and the various propulsion devices for aircraft, missiles, satellites and space vehicles.
| 8 |
Author(s):
Obed Tiwah John, Danjuma Jibasen, S. S. Abdulkadir , Shakuntla Singla .
Page No : 105-121
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Modelling Service Times Using Beta-Based Compound Distribution.
Abstract
The design of the queueing model involves modelling the arrival and service processes of the system. Conventionally, the arrival process is assumed to follow Poisson while service times are assumed to be exponentially distributed. Other distributions such as Weibull, uniform, lognormal have been used to model service times however, generalized distributions have not been used in this regard. In recent times, attention have been shifted to generalised families of distributions including Beta generalized family of distributions which led to the development of Beta-based distributions. Distributions generated from a mixture of beta random variables are quite numerous in literature with little or no application to service times data. In this study, six Beta-based compound distributions namely; Beta-Log-logistic distribution (BLlogD), Beta-Weibull distribution (BWeiD), Beta-Lomax distribution (BLomD), Beta-exponential distribution (BExD), Beta-Gompertz distribution (BGomD) and Beta-log-normal distribution (BLnormD)) were compared with the classical service times model on four service times data sets. Maximum likelihood estimator was employed in estimating parameters of the selected models while Akaike Information Criteria (AIC), Consistent Akaike Information Criterion (CAIC), Bayesian Information Criterion (BIC) and Hannan Quin information criterion (HQIC) statistics were employed to select the best model. CDFs, PDFs and PP-plots were used to fit the data of the suggested models. Results from the study shows that Beta-Exponential distribution (BExpD) performed better for the datasets I (AIC=640.3, CAIC=640.5,BIC=648.1 and HQIC=643.4), Beta-weibull distribution (BWeiD) performed better for the data sets II and III (AIC=204.2, 2142.4,CAIC=204.2, 2142.7,BIC=212.8, 2154.9 and HQIC=207.6, 2147.5) while Beta-log-logistic distribution (BLlogD) performed better for the data sets IV (AIC=2275.3,CAIC=2275.5, BIC=2289.3 and HQIC=2280.9). Findings from this study revealed some useful Beta-based compound distributions which performed better than the conventional service time model. From the findings of this study, we recommend researchers to dive deep into queueing theory.
| 9 |
Author(s):
Zayyanu Sahabi Yabo, Abdullahi Hussaini, Isah Bala Yabo.
Page No : 122-133
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Conjugate Impacts of Linear Variable Thermal Conductivity and Thermal Radiation on Nonlinear Electrically Conducting Fluid.
Abstract
This study investigates the conjugate impacts of variable thermal conductivity and thermal radiation on nonlinear heat conducting fluid moving vertically through parallel channel. The dimensional governing equations were reduced to dimensionless partial differential equations and consequently transformed to ordinary differential equations. The resulting ordinary differential equations were solved using homotopy perturbation method. The study aimed at discovering the possible effects of thermal radiation parameter, thermal conductivity parameter, temperature difference parameter and Magnetic parameter through the help of line graphs. It was found that, Velocity and temperature distributions were increasing functions of , while Velocity and temperature distributions are decreasing functions of
Thermal conductivity parameter
| 10 |
Author(s):
I. M. Mankilik, S. A. Ihedioha.
Page No : 134-146
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Optimized Investment Strategy and Proportional Reinsurance of Insurance Company under Ornstein–Uhlenbeck and Geometric Brownian Motion Models.
Abstract
In this work we investigated the optimization of an insurer’s investment strategy and the proportional reinsurance rate of his portfolio under power utility preference in the cases of correlating and non-correlating Brownian motions. The market in which insurer traded two assets; a risky asset which price process was governed by the geometric Brownian motion (GBM) and riskless asset that had its price driven by the Ornstein-Uhlenbeck stochastic model. We derived the required Hamilton-Jacobi-Bellman Equation (HJB) by applying the maximum principle of dynamic programming and the elimination of dependency on variables was used to obtain the analytic solutions of optimizes investment strategy and the proportional reinsurance rate.
| 11 |
Author(s):
Onyebuchi Benedicta Amolo, Emwinloghosa Kenneth Guobadia, JohnPaul Kenechukwu Iwuchukwu.
Page No : 134-152
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Extending a Level Three Order Polynomial Probability Model.
Abstract
An inverse and power extension were derived for a three order polynomial probability distribution and
studied in this paper as post-development. The two extensions serve to make up for the limitations of their
baseline model. Some relevant properties: shape of the PDF, moments, survival function, hazard function,
quantile function, stress-strength reliability, order statistics and parameter estimations were studied. The
hazard shapes of the distributions were found to be - inverted bathtub for the former; and three different
shapes namely: increasing function, decreasing function and bathtub, for the later. This implies that the
distributions can altogether model many varieties of datasets emanating from different life phenomena.
This statement “if ( ) , then ( ) ” was examined and was discovered to apply for
exponential distribution but not any of the extended distributions and the baseline distribution too.
Finally, the extensions showed to be competent over both the baseline distribution and their respective
counterpart distributions, with respect to the datasets used. For the later, the superiority was accountably
hinged on the extra parameters; since the dataset has an outlier.
| 12 |
Author(s):
Mark Nwachukwu Ugo, John Paul Kenechukwu Iwuchukwu, Emwinloghosa Kenneth Guobadia.
Page No : 153-161
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Perfect Hemisphere Trend Realization: A Combinatorial Modification of Probability Distributions.
Abstract
The paper reviews creative ways to developing continuous probability models playing around integration method and the concept of normalization. It further projects a probability distribution realized by combining two symmetric probability models that differ in shape, to produce a perfect hemisphere or half-sun trend. Normal and arcsine distributions are the root distributions used for this development. At some values of the parameter, the distribution can be right skewed; where other moments and related measures, and estimation are studied as its properties, alongside simulation.
| 13 |
Author(s):
Asogwa O. C., Eze N. M., Christopher C. C., Aruah K. E., Chimezie I. E..
Page No : 162-173
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On the Comparative Study of the Supervised Machine Learning Models.
Abstract
This research empirically compared the performance of three supervised machine learning models which are Multinomial Logistic Regression (MLR), Multilayer back propagated Neural Networks (MNN) and Multinomial Decision Trees (MDT) based on a tested data set for the opinion of Nigerian citizens during the period of naira redesign policy using classification matrix criterion. About 600 copies of questionnaires on the opinion of Nigeria citizens on their individual welfare at the period of naira redesign. The result showed that, ANN outperformed other models with 94.4% correct classification rates, followed by the MLR with correctly classification rates of 93.5% and lastly by MDT with correct classification rates of 90.0%.
| 14 |
Author(s):
Agbedeyi O. D., Maliki S. O., Asor V. E..
Page No : 174-187
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A Time Dependent Neural Network Model for the Prediction and Forecasting of Bitcoin Price.
Abstract
In this research work, we developed a mathematical model of a digital currency market, involving daily closing price as a function of time. We proposed the Artificial Neural Network (ANN) model. We observed that our ANN model was able to predict the daily closing price of Bitcoin and also make six weeks forecast to a reasonable degree of accuracy. We equally observe that the time dependent ANN model can actually give digital currency traders and investors a clue on when to trade off their digital assets with minimum risk. We therefore, recommend that ANN model should be incorporated into digital currency trading platforms as a signal tool to enable digital currency traders take more informed and less risky trading decisions. From our findings, we would advise traders who wish to employ ANN model to consider a smaller time frame say a few weeks’ time interval for their predictions. We observed also that ANN models have limitations when it comes to manual computation or implementation in Microsoft Excel, especially when dealing with very large input values. This is because of the saturation characteristic of our ANN inner layer activation function (viz; tanh function) which can lead to identical output values for different input values, making it difficult to replicate the ANN model's behavior. Furthermore, ANN models often involve complex interactions between multiple neurons, layers, and activation functions, which can be challenging to replicate manually.
| 15 |
Author(s):
Agbedeyi O. D., Maliki S. O., Asor V. E..
Page No : 188-204
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A Predictive Model for Digital Currencies Prices using Geometric Brownian Motion Stochastic Differential Equation: A Case Study of the Bitcoin.
Abstract
In this research work, we developed a predictive model for digital currency prices, involving daily closing price as a function of time. We used the Geometric Brownian motion stochastic differential equation which was solved using inbuild functions in Microsoft Excel. While we used the Bitcoin as our case study, our model was able to predict the daily closing prices of Bitcoin to a reasonable degree of accuracy. We equally observe that the time dependent Geometric Brownian motion stochastic differential equation cannot give digital currency traders and investors a clue on when to trade off their digital assets. Thus, it become very risky using our model to make well informed trading decisions. We therefore, recommend that for minimum risk, trades and investors in digital currencies should consider a combination of other signal tools to take more informed and less risky trading decisions.
| 16 |
Author(s):
Samuel Hwere Tsok, Sabo Hama, M. S. Adamu.
Page No : 205-225
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Exploring the Primitivity and Regularity of Dihedral Groups of Degree 5p Using Numerical Approaches.
Abstract
This paper delves into exploration of primitivity and regularity of Dihedral groups of degree 5p, where p is prime, focusing on cases where these groups are not p-groups. By utilizing numerical approaches, the properties of these groups are examined to shed light on their structure, behavior, and underlying algebraic characteristics. Key numerical methods are employed to calculate invariants and test conditions for primitivity and regularity in these groups. [20][13]
| 17 |
Author(s):
Robert Folorunsho Akerejola (Ph.D.), Elakhe O. A., Isere A. O..
Page No : 226-247
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A Non-Standard Finite Difference Discretization Scheme Applied to a Malaria Model.
Abstract
In this research work, a dynamically consistent non-standard finite difference (NSFD) scheme is developed to solve a continuous-time model of malaria transmission with herbal medicine as control strategy. We compared results from NSFD scheme with the standard finite difference methods (4th order Runge-kutta and forward Euler methods). The numerical investigation showed that the proposed NSFD method remains consistent, preserves the positivity of solutions and converges to true equilibrium points of the continuous model independent of the step size h.
