Volume 35, Issue 1 (June)

Articles in this Issue

8 articles
1
Research Article DOI: 10.67897/njma.2025.ouxb5w0m

Double-Blinded One-Time-Password Key Generation for Authentication in Internet of Things (IoT)

A. J. Saka*, Segun Aina, Omolara Aminat Ogungbe, Kehinde Adam Olurode, Ishaya Peni Gambo, Oluwafemi Joshua David, K. Rauf

This paper is proposing a novel technique that generates an unpredictable digit-size at every time of authentication. In this technique, neither the authentic user nor the hacker can have the prior knowledge of the digit-size not to think of the combinatorial (sequence or random order) of the anticipated keys. Indeed, this is simply referred to as Double-Blinded One-Time Password Key Generation (D...

Jun, 2025 pp. 1-15 3 views
2
Research Article DOI: 10.67897/njma.2025.sous04pg

On qpb–Condensed Ciri´c–Reich–Rus type contractions in ˇ Quasi-Partial b-metric Spaces

I. F. Usamot*, K. Rauf, A. Y. Akinyele

Fixed point theory in generalized metric spaces has received considerable attention due to its wide applicability in nonlinear analysis. In this work, we introduce a new class of nonlinear contractions, termed qpb–Condensed Ciri´c–Reich–Rus type ˇ contractions (qpb − CCRR), defined on complete quasi-partial b-metric spaces. The proposed contraction incorporates asymmetric self-distances and the co...

Jun, 2025 pp. 16-28 6 views 2 downloads
3
Research Article DOI: 10.67897/njma.2025.7lydn2ax

On Polynomials Derived from Topological Indices of Special Graphs

Aliyu Ibrahim Kiri*, Aliyu Suleiman, Bilkisu Tijjani

Polynomials associated with topological indices are defined from graph-based indices with their coefficients and exponents derived from these values. This paper presents formulae for such polynomials for cycle Cn, wheel Wn, path Pn, complete graph Kn and complete bipartite graph Km,n. It is further shown that a graph is a closed path if and only if its first and second Zagreb indices coincide.

Jun, 2025 pp. 29-42 5 views
4
Research Article DOI: 10.67897/njma.2025.l5iurwxm

Enhancing Volatility Forecasting: A Comparative Study of GARCH(1,1) Models with Non-Normal Error Distributions

O. S. Makinde*, A. A. Olosunde, O. K. Agunloye

This study proposes a GARCH(1, 1) model with generalized logistic distribution (GLD) errors to better capture skewness and kurtosis in financial returns. Using crude oil price data, it compares GLD with GED and Student’s t-distributions. Results show the GLD-based model outperforms others in forecasting accuracy and volatility modeling.

Jun, 2025 pp. 43-50 3 views
5
Research Article DOI: 10.67897/njma.2025.u1vf4nxg

Equilibrium Analysis of Bertrand Competition Model

Abdulhakim Muhammad*, Aminu Muhammad

This paper offers a comprehensive examination of the major competition models in microeconomics, with a central emphasis on the Bertrand framework. In addition to Bertrand price competition, the paper also reviews different competition models to highlight how firms’ strategic choices shape market outcomes. The analysis contrasts price-based and quantity-based competition and evaluates their impact...

Jun, 2025 pp. 51-70 3 views
6
Research Article DOI: 10.67897/njma.2025.bu0d8o9t

Polynomial Bounds for Bi-Univalent Functions Associated with Sigmoid Function and Q− Derivative Over a Chebyshev Polynomials

I. T. Awolere*, A. M. Gbolagade

This paper introduces a new subclass of the function class P of biunivalent analytic functions defined in the open unit disk, associated with a certain operator and the Sigmoid function via Chebyshev polynomials. Bounds for the initial coefficients are obtained for the defined class, along with results for the Fekete–Szeg¨o functional. Furthermore, by varying the parameters involved, several resul...

Jun, 2025 pp. 71-81 5 views 1 downloads
7
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 3 views
8
Research Article DOI: 10.67897/njma.2025.auppw045

Tian Invariant on the Blown-up Grassmannian Futaki Obstructions and K-Stability

Riadh JELLOUL*

In this paper, we compute the Tian invariant on a generalization of Calabi manifolds introduced by the author in collaboration with A. Ben Abdesselem and M. Filali in [1]. We adapt the method of the original article to the setting of complex Grassmannians blown up along linear subvarieties. Our original contribution is fourfold: we explicitly determine the subgroup H ⊂ Aut(G(k, n)) = P GL(n, C) th...

Jun, 2025 pp. 92-111 7 views 2 downloads
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