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193 articles
91
Research Article DOI: 10.67897/njma.2022.hfxgvhz7

Stability of Solutions for a Class of Second Order Nonlinear Integro-Differential Equations with Delay

Daniel Oluwasegun Adams*, Rasheed A ADETONA, Musiliu Tayo Raji, Samson Abidemi Oni, Akinwale Lewis Olutimo

In this paper, we investigate the stability of solutions for a class of second order nonlinear delay integro-differential equations by using a suitable Lyapunov-Krasovskiˇi functional with sufficient conditions to establish some new results. An example is given to show the validity of the results obtained.

Jun, 2022 pp. 80-89 11 views 4 downloads
92
Research Article DOI: 10.67897/njma.2016.5qm8hycl

Modified Variational Homotopy Perturbation Method for Nonlinear Volterra Integro-differential Equations

Ignatius N. Njoseh*, Ebimene J. Mamadu

In this paper, we apply the Modified Variational Homotopy Method (MVHPM) for the numerical solution of nonlinear Volterra integro-differential equations. The method is an elegant mixture of Variational Iteration and Homotopy Perturbation Methods. The modification is effected at the approximation stage. This modification is the addition of the coecients of the least and highest powers of the homot...

Jun, 2016 pp. 80-87 4 views 4 downloads
93
Research Article DOI: 10.67897/njma.2026.xa92ictk

On Specification of Almon Distribued Lag Model in the Presence of Multicollinearity

T. K. Ajetunmobi, O. K. Agunloye*

In Almon distributed lag modeling, presence of multicollinearity, choice of appropriate approximating polynomial of suitable degree and choice of optimal truncation lag-length required for the implementation of Almon distributed lag model constitute three major problems confronting Almon distributed lag modeling.Given the fact that the choice of appropriate approximating polynomial of suitable deg...

Jun, 2026 pp. 81-91 24 views 8 downloads
94
Research Article DOI: 10.67897/njma.2025.4ciazhok

Forecasting Monthly Inflation Rate in Nigeria Using Causal and Invertible Autoregressive Moving Average Models

O. K. Agunloye*, K. A. Alamu

This paper evaluates causal and invertible ARMA models for forecasting Nigeria’s inflation rate. After testing stationarity and fitting candidates, the ARMA(1, 4) model emerged as optimal. It satisfies causality, invertibility, and outperforms alternatives across loss functions.

Jun, 2025 pp. 82-90 10 views 3 downloads
95
Research Article DOI: 10.67897/njma.2017.epqnpaq4

MODELLING AND EVALUATION PERFORMANCES WITH NEURAL NETWORK USING CLIMATIC TIME SERIES DATA

T. O. Olatayo*, A. I. Taiwo

Neural network model is an alternative powerful data modeling tool capable of capturing and representing non-linear relationship between variables. The methodology used in this research article were Artificial Neu ral network (ANN), Autoregressive Integrated Moving Average (ARIMA) and fuzzy time series (FTS) models. The study revealed that, since ANN forecast performance evalu ation has the lowest...

Sep, 2017 pp. 83−94 11 views 4 downloads
96
Research Article DOI: 10.67897/njma.2015.phrqrrwz

FIVE SHORT NOTES ON BOUNDED MAPS

SUNDAY OLUYEMI*

This paper contributes five observations on bounded maps: (i) An observation on the definition of a bounded set, (ii) Three characterizations of bounded linear maps that parallel the usual general topology characterizations of continuity, (iii) An analogue of [2, PROPOSITION 3.12.1 p.254][7, Lemma 11.1.1, p.164] for bounded maps, (iv) That the Banach-Steinhaus Closure Theo rem is also true for bou...

Dec, 2015 pp. 87−99 9 views 4 downloads
97
Research Article DOI: 10.67897/njma.2016.c2n2njj8

Estimating Infant and Maternal Mortality in Nigeria using Overdispersion Modelling Methods

C. I. Orabuche*, M. O. Adamu, O. E. Oladokun

In this study, models that provide more satisfactory statistical fit for data and factors that a ect infant and maternal mortality rates in Nigeria are presented. Models that detect and correct overdispersion in data are used to analyze the data provided by the National Bureau of Statistics, Nigeria. Some of the models considered are Poisson, Poisson Normal, Negative Binomial, Quasi-likelihood and...

Jun, 2016 pp. 88-110 3 views 7 downloads
98
Research Article DOI: 10.67897/njma.2022.698ddx0p

Result on Partially Ordered Compact Spaces

T. M. Asiru*, R. A. Ibitowa

Partially ordered compact spaces were considered in the paper. E denote a compact Harsdorff space, C(E) denote the set of all continuous real valued functions on the compact Harsdorff space E, C+(E) is the set {f ∈ C(E) : f (t) ≥ 0, ∀t ∈ E} . ≤ denotes a relation of partial order given in E. That is, a binary relation that is reflexive (x ≤ x∀x ∈ E) antisymmetric x ≤ y and y ≤ ximpliesx = y, ∀x, y...

Dec, 2022 pp. 89-93 4 views 3 downloads
99
Research Article DOI: 10.67897/njma.2018.lg6xndnb

An Operator for Obtaining Nth Order Derivative of a Function Depending on Seven Independent Variables

O. O. Enoch*, F. J. Adeyeye, A. O. Ilesanmi, S. O. Adejuwon

Leibnitz's theorem is used in the product rule to generatea series method for computing the nthorder derivative ofa function that depends on seven Independent variables.The new series method does not require the knowledge ofthe preceding derivative before obtaining the succeedingones. A generalization of the method is also presented.

Jun, 2018 pp. 89-98 3 views 5 downloads
100
Research Article DOI: 10.67897/njma.2022.bzn36s9k

Modelling Thermo-physical Effects of Heat and Mass Transfer in Unsteady MHD Viscoelastic Fluid Flow in inclined Porous Media

S. A. Amoo*, I. M. Daniel, A. O. Amoo

This research presents the modelling thermo physical effects of heat and mass transfer in unsteady Magnetohydrodynamics MHDviscoelastic fluid flow in inclined porous media. The resulting governing boundary layer equations were non-linear and coupled form of partial differential equations, and they were solved by using fourth order Runge-Kutta integration scheme with Newton Raphson shooting method....

Jun, 2022 pp. 90-103 12 views 5 downloads