Journal of the Nigerian Society of Physical Sciences
https://journal.nsps.org.ng/index.php/jnsps
<p>Journal of the Nigerian Society of Physical Sciences is a peer-reviewed journal published quarterly (February, May, August & November) by the <a href="https://nsps.org.ng/" target="_blank" rel="noopener">Nigerian Society of Physical Sciences</a>. It offers an exciting publication outlet for Physical Science reports.</p>Nigerian Society of Physical SciencesenJournal of the Nigerian Society of Physical Sciences2714-2817<div class="page"> <div class="page"> <p>The Journal of the Nigerian Society of Physical Sciences (JNSPS)<em> is</em> published under the <a href="http://creativecommons.org/licenses/by/4.0/"><strong>Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)4.0 (CC BY-NC) license</strong>.</a> This license was developed to facilitate open access, namely, it allows articles to be freely downloaded and to be re-used and re-distributed without restriction, as long as the original work is correctly cited. More specifically, anyone may copy, distribute or reuse these articles, create extracts, abstracts, and other revised versions, adaptations or derivative works of or from an article, mine the article even for commercial purposes, as long as they credit the author(s).</p> </div> </div>Hyper-parameter tuning for support vector machine using an improved cat swarm optimization algorithm
https://journal.nsps.org.ng/index.php/jnsps/article/view/1007
<p class="p1">Support vector machine (SVM) is a supervised machine learning algorithm for classification and regression problems. SVM performs better when combined with other classifiers or optimized with an optimization algorithm. The SVM parameters such as kernel and penalty have good performance on the classification accuracy. Recently, a lot of evolutionary optimization algorithms were used for optimizing the SVM. In this paper, an Improved Cat Swarm Optimization (ICSO) was proposed for optimizing the parameters of SVM with the aim of enhancing its performance. CSOs have the problem of a low convergence rate and are easily trapped in local optima. To address this problem, a new parameter was added to the velocity for the tracing mode and the Opposition-Based Learning (OBL) technique was used to modify the CSO algorithm (ICSO-SVM). A new parameter was introduced to guide the cats’ positions to the local and global best positions in the velocity tracing mode of the CSO algorithm. The proposed algorithm was verified using 15 datasets from the University of California Irvine (UCI) data repository and also six different performance metrics were used. The experimental results clearly indicate that the proposed method performs better than the other state-of-the-art methods.</p>
Original ResearchMathematical, Computer & Statistical SciencesCat Swarm OptimizationSupport Vector MachineOpposition-based learningComputer ScienceMachine LearningOptimizationSilifat Adaramaja AbdulraheemSalisu AliyuFatima Binta Abdullahi
Copyright (c) 2023 Silifat Adaramaja Abdulraheem, Salisu Aliyu, Fatima Binta Abdullahi
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2023-09-082023-09-081007100710.46481/jnsps.2023.1007Effect of reduction method on the performance a software defined network system using Gumbel Hougaard family copula distribution
https://journal.nsps.org.ng/index.php/jnsps/article/view/1402
<p>This study examines a system that consists of three subsystems 1, 2 and 3. These three subsystems are each linked together in series. Subsystem 1’s three units are wired in series, subsystem 2’s three units are wired in parallel and operating under the 2-out-of-3: G; policy, and subsystem 3’s three units are wired in parallel and operating under the 1-out-of-3: G; policy. Units and subsystems failure rates are constant and follow an exponential distribution. The repair rate follow two types of distributions, namely general and Gumbel Hougaard family copula distribution. The system was studied using Laplace transforms and supplementary variable methods. For specific values of the failure and repair rates, availability, reliability, mean time to failure (<em>MTTF</em>), and cost analysis have been assessed. As a means to improve the system’s overall effectiveness and availability, a reduction strategy is utilized. Tables and graphs are used to display computed results.</p>
Original ResearchMathematical, Computer & Statistical SciencesReliabilityAvailabilityMTTFCost analysisA redundant systemComplex systemk- out-of- n systemsGumbel- Hougaard family copula distributionReliability analysiscost benefit analysisElsayed Elshoubary
Copyright (c) 2023 Elsayed Elshoubary
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2023-09-012023-09-011402140210.46481/jnsps.2023.1402Isolation, Characterization, Antimicrobial and Theoretical Investigation of Some Bioactive Compounds Obtained from the Bulbs of Calotropisprocera
https://journal.nsps.org.ng/index.php/jnsps/article/view/1576
<p class="western" lang="en-GB" style="margin-bottom: 0cm;" align="justify"><span style="font-family: Times New Roman, serif;">This study characterizes the bioactive molecules from the bulb of </span><span style="font-family: Times New Roman, serif;"><em>Calotropisprocera</em></span><span style="font-family: Times New Roman, serif;"> and investigates the antimicrobial activities of the crude extracts. Theoretical studies on the two isolated compounds in the crude extract were also accomplished.The bulbs were air dried, pulverized, and subjected to extraction procedures by maceration using 500 mL each of normal-hexane, ethyl acetate and methanol. The crude extracts were further tested onmicroorganisms and phytochemical screening </span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;">using standard procedures</span></span><span style="font-family: Times New Roman, serif;">. In addition, the bioactive compounds in the extract were screened against DNA gyrase of two Gram negative bacterial species; </span><span style="font-family: Times New Roman, serif;"><em>Escherichia coli </em></span><span style="font-family: Times New Roman, serif;">and </span><span style="font-family: Times New Roman, serif;"><em>Salmonella typhi</em></span><span style="font-family: Times New Roman, serif;">using Molecular Docking simulation techniques and further subjected to ADMET profiling,using the </span><span style="font-family: Times New Roman, serif;">Swiss ADME online server</span><span style="font-family: Times New Roman, serif;">. The Crude ethyl acetate extract has the highest effective activity against </span><span style="font-family: Times New Roman, serif;"><em>Escherichia coli </em></span><span style="font-family: Times New Roman, serif;">(MIC 2.5mg / mL and MBC/MFC 5mg / mL), </span><span style="font-family: Times New Roman, serif;"><em>Staphylococcus aureus </em></span><span style="font-family: Times New Roman, serif;">(MIC 2.5mg/mL), </span><span style="font-family: Times New Roman, serif;"><em>Candida albicans, Salmonella typhi</em></span><span style="font-family: Times New Roman, serif;">and</span><span style="font-family: Times New Roman, serif;"><em> Candida stellafoidea </em></span><span style="font-family: Times New Roman, serif;">(MIC 5mg/mL). beta-Amyrin acetate and Taraxasterol are the two phytochemicals in the purified white crystalline fractions and were found to fasten to the active sites of DNA gyrase of the Gram negative bacterial species </span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;">via hydrophobic and hydrogen bond interactions, with binding activity value of -9.6 kcal/mol and -9.5 kcal/mol, respectively. Also, ADMET investigations of the compounds revealed their sound oral bioavailability and excellent pharmacokinetic and toxicity profiles. The findings of this study could provide a platform for discovering safe and potent antibiotics against pathogenic microbes ravaging our society.</span></span></p>
Original ResearchChemistryPhytochemical ScreeningAnti-microbial screeningCalotropis proceraPharmacokineticsorganic chemistrycomputational chemistrynatural productsMuluh Emmanuel KhanChijioke Ezekiel ElumAugustina Onyebuchi Ijeomahhilip John AmejiIzuagbe Gilbert OsigbemheEmmanuel Etim (PhD)John Veshima AnyamAlexander AbelCyprianTernenge Agber
Copyright (c) 2023 M. E. Khan, C. E. Elum, A. O. Ijeomah, P. J. Ameji, I. G. Osigbemhe, E. E. Etim, J. V. Anyam, A. Abel, C. T. Agber
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2023-08-012023-08-011576157610.46481/jnsps.2023.1576Experimental and computational studies of the corrosion inhibitive effects of Zingiber officinale rhizomes on mild steel corrosion in acidic solutions
https://journal.nsps.org.ng/index.php/jnsps/article/view/1386
<p class="western" style="margin-bottom: 0cm; line-height: 100%;" align="justify"><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">The study investigates the anticorrosion potentials of </span></span><span style="font-family: Times New Roman, serif;"><span style="font-size: large;"><em>Zingiber officinale </em></span></span><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">(ZO) on mild steel induced in 1.0 M HCl and 0.5 M H</span></span><sub><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">2</span></span></sub><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">SO</span></span><sub><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">4</span></span></sub><span style="font-family: Times New Roman, serif;"><span style="font-size: large;"> acid solution respectively using structural characterization (gas chromatography-mass spectroscopy, GC-MS and Fourier transform infrared spectroscopy, FTIR) and electrochemical (electrochemical impedance spectroscopy, EIS and potentiodynamic polarization, PDP) techniques respectively and theoretical simulations. The structural characterization was performed to identify chemical constituents and functional groups present in the plant extract whereas electrochemical techniques and theoretical computations were used to examine the anticorrosion potentials of the extract and validate the experimental results. The GC-MS result revealed the presence of twenty-three (23) compounds within the extract and out of which three (</span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">1-(1,5-dimethyl-4-hexenyl)-4-methyl-, dodecanoic acid and </span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">9-Octadecenoic acid (Z)-2-hydroxy-1-(hydroxymethyl)ethyl ester)</span></span></span><span style="font-family: Times New Roman, serif;"><span style="font-size: large;"> were selected for computational simulation and the results of FTIR revealed the presence of the following functional groups (O-H, C=C, C=O, C-C and C-H) in the ZO extract. The results of EIS revealed that extract of ZO exhibited corrosion inhibition efficieny of 82.7% and 93.6 % for mild steel in </span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">1 M HCl and 0.5 M H</span></span></span><span style="color: #000000;"><sub><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">2</span></span></sub></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">SO</span></span></span><span style="color: #000000;"><sub><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">4</span></span></sub></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: large;"> solution respectively </span></span></span><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">at maximum inhibitor concentration of 1000 mg/L for mild steel. Also, PDP results revealed that ZO extract functioned as mixed inhibitor because both the anodic and cathodic reaction process was altered. The quantum chemical calculation results revealed that </span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">9- Octadecenoic acid (Z)-2-hydroxy-1-(hydroxymethyl) ethyl ester had a good energy gap (\Delta E) compared to other two compounds, indicating its better adsorption interaction with the metal surface in sulfuric acid environment. This was further confirmed by its good adsorption energy of -</span></span></span><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">355.55 Kcal/mol with mild steel surface in H</span></span><sub><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">2</span></span></sub><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">SO</span></span><sub><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">4 </span></span></sub><span style="font-family: Times New Roman, serif;"><span style="font-size: large;">environment compared with -167.81Kcal/mol in HCl environment from the molecular dynamic simulation.</span></span></p>
Original ResearchChemistryZingiber officinalesolvation moleculescorrosionmolecular dynamic simulation,Inhibition EfficiencyChemistryChinonso AdinduSimeon NwanonenyiChinyere Ikpa
Copyright (c) 2023 C. B. Adindu, S. C. Nwanonenyi, C. B. C. Ikpa
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2023-08-122023-08-121386138610.46481/jnsps.2023.1386Modeling and Analysis of a Fractional Visceral Leishmaniosis with Caputo and Caputo–Fabrizio derivatives
https://journal.nsps.org.ng/index.php/jnsps/article/view/1453
<p>Visceral leishmaniosis is one recent example of a global illness that demands our best efforts at understanding. Thus, mathematical modeling may be utilized to learn more about and make better epidemic forecasts. By taking into account the Caputo and Caputo-Fabrizio derivatives, a frictional model of visceral leishmaniosis was mathematically examined based on real data from Gedaref State, Sudan. The stability analysis for Caputo and Caputo-Fabrizio derivatives is analyzed. The suggested ordinary and fractional differential mathematical models are then simulated numerically. Using the Adams-Bashforth method, numerical simulations are conducted. The results demonstrate that the Caputo-Fabrizio derivative yields more precise solutions for fractional differential equations.</p>
Original ResearchMathematical, Computer & Statistical SciencesLeishmaniosis, Modelling, Caputo, Caputo–Fabrizio, SudanModellingFractional Derivativethe Numerical AnalysisSimulationDalal Khalid AlmutairiMohamed A. AbdoonSalih Yousuf Mohamed SalihShahinaz A.ElsamaniFathelrhman EL GumaMohammed Berir
Copyright (c) 2023 Dalal Khalid Almutairi, Mohamed A. Abdoon, Salih Yousuf Mohamed Salih, Shahinaz A.Elsamani, Fathelrhman EL Guma, Mohammed Berir
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2023-07-262023-07-261453145310.46481/jnsps.2023.1453Photocatalytic and antibacterial activities of green-mediated Khaya senegalensis-silver nanoparticles and oxidized carbon nanotubes
https://journal.nsps.org.ng/index.php/jnsps/article/view/1438
<p>This study investigated the photocatalytic and antibacterial activities of plant-mediated silver nanoparticles (AgNPs) from a medicinal plant extract of Khaya senegalensis (K. senegalensis) and oxygen functionalized carbon nanotubes (oCNTs), respectively. The CNTs were functionalized using acid treatment. The green synthesized AgNPs from K. senegalensis (KS-AgNPs) and oCNTs were characterized by UV–Visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), transmission emission microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The formation of KS-AgNPs was confirmed by the UV–Vis absorption spectra, which showed an absorption band at 427 nm with a color change from yellow to brown. The morphology of KS-AgNPs was spherical in shape, with an average particle size of 9.30 nm. The FTIR analyses revealed distinctive functional groups, such as, hydroxyl (O-H), amines (N-H), and carbonyl (C-O), which were directly involved in the synthesis and stability of AgNPs. The XRD spectra was distinctive with five intense peaks at 2theta angles of 38.12°, 44.28°, 64.43°, 77.48°, and 81.54<sup>o</sup> while oCNTs gave intense peaks at 2theta angles of 26.43<sup>o</sup>, 42.36<sup>o</sup>, 44.46<sup>o</sup>, 54.51<sup>o</sup>, 59.98<sup>o</sup>, and 77.40<sup>o</sup>. The photocatalytic property of green synthesized KS-AgNPs was determined to be 40.7 % higher than that of oCNTs when applied for treatment of industrial waste water. The ability of green-mediated KS-AgNPs to inhibit against gram-positive and gram-negative bacteria was observed to be that gram (-) bacteria (E. coli) was more susceptible to KS-AgNPs than the gram (+) bacteria (S. aureus), in which case their susceptibility was least in oCNTs for both bacteria, respectively.</p>
Original ResearchChemistryKhaya senegalensissilver nanoparticlescarbon nanotubesphotocatalyticantibacterial activityNanoscienceNanotechnologyGreen ChemistryA. H. LabuloAugustine TernaO. F. OladayoH. I brahimN. S. TankoR. A. AshonibareJ. D. OpeyemiZ. Tywabi-Ngeva
Copyright (c) 2023 A. H. Labulo, A. D. Terna, O. F. Oladayo, H. Ibrahim, N. S. Tanko, R. A. Ashonibare, J. D. Opeyemi, Z. Tywabi-Ngeva
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2023-06-212023-06-211438143810.46481/jnsps.2023.1438Simulation of the Movement of Groundwater in an Aquifer
https://journal.nsps.org.ng/index.php/jnsps/article/view/1512
<p style="text-align: justify;">This study investigates the impact of extracting fresh water from areas where salt water and fresh water meet in tropical regions. Traditionally, fresh water is expected to be found above salt water in the ocean or underground. To carry out the investigation, Green's Function method is used, and a numerical chart is presented that includes an equation derived from Green's II matching. The study computes the shape of the interface during water withdrawal and flows through the basins and sources of the line. In addition, this study obtains an analytical solution to the linear problem for the non-withdrawal scenario. Finally, the study identifies the maximum rate of water withdrawal before the initial breakthrough of salt water for different density ratios.</p>
Original ResearchMathematical, Computer & Statistical SciencesFree Surface, Tropical Island, Porous Medium, Freshwater Lens, Island Tub, Green’s Function.Suha Ibrahim Salih AL-AliNihad Jalal Kadhem AL-Awsi
Copyright (c) 2023 Suha Ibrahim Salih AL-Ali, Nihad Jalal Kadhem AL-Awsi
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2023-06-222023-06-221512151210.46481/jnsps.2023.1512Optical, Dielectric and Optoelectronic Properties of Spray Deposited Cu-doped Fe2O3 Thin Films
https://journal.nsps.org.ng/index.php/jnsps/article/view/1180
<p>Copper-doped hematite thin films were prepared by spray pyrolysis technique using a mixture of ethanol and distilled water precursors. Visual observations showed that aqua precursor produced films of less integrity compared with ethanol that produced thin, uniform and transparent yellowish-brown films that adhered well to the substrate. Composition and thickness measurements determined by RBS revealed that ethanol precursor produced thinner films of 94.45 and 51.77 nm while aqua precursor produced films of 1,370 and 1,120 nm for undoped and Cu-doped Fe2O3 respectively. This is an indication that ethanol solutions produced nano-thick films of high integrity. The composition revealed that only the Cu-doped Fe2O3 deposited by ethanol solution gave composition close to stoichiometric Fe2O3 while the others gave non-stoichiometric Fe(OH)3 . Optical characterization carried out using UV-visible spectrophotometer in transmittance mode indicated that the film thickness was directly proportional to the number of passes which is inversely proportional to the transmittance. Three bandgap determination methods namely; Tauc, Absorption Fitting Spectrum (AFS) and Davis-Mott were employed with the result that Tauc and AFS gave close direct and indirect bandgap energies (Eg) of 3.44 and 1.98 for AFS and 3.43 and 2.32 eV for Tauc respectively. The Urbach tail energy determined was 1,100 meV which is an indication of a broad onset of absorption. The steepness parameter (?) was found to be 7.83 while the electron-phonon (Eph ) coupling energy was found to be 0.85 eV. It was also observed that the refractive index (n) was about 15 times greater than the extinction coefficient (k). In the study of the dispersion parameters using single oscillator and Sellmier models, the values of the single oscillator energy (Eosc ), dispersion energy (Ed), zero frequency dielectric constant, zero frequency refractive index, the average oscillator strength (So), the average oscillator parameter and the dispersion parameters were determined. All the values of the parameters estimated are of the same order of magnitude with other semiconducting materials. The study showed that Cu-doped Fe2O3 could be employed as dielectric material as well as in optoelectronic devices. </p>
Special Issue : 3rd biennial AScIN conference OAU, NigeriaPhysics & AstronomyChemistrythin filmbandgapUrbach Energyrefractive indexdispersion parametersOscillator parametersPhysicsAdeniyi Yisau FasasiEmmanuel AjenifujaEdward OsagieLukman AnimashaunAbiodun AdeoyeEusebius Obiajunwa
Copyright (c) 2023 A. Y. Fasasi, E. Ajenifuja, E. Osagie, L. O. Animasaun, A. E. Adeoye, E. I. Obiajunwa
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2023-06-142023-06-141180118010.46481/jnsps.2023.1180Corrosion Inhibition Properties of Lawsone Derivatives againts Mild Steel: A Theoretical Study
https://journal.nsps.org.ng/index.php/jnsps/article/view/1371
<p>Theoretical studies have been carried out using DFT, ab initio MP2 and Monte Carlo (MC) simulations of corrosion inhibitors from lawsone derivatives against carbon steel. The research focuses on studying the effect of substituent groups in the lawsone structure on the efficiency of corrosion inhibition in mild steel. Quantum chemical parameters of lawstone inhibitors in neutral and protonated conditions have been calculated. Fukui’s function analysis predicts that the active side of the inhibitor will be adsorbed on the mild steel surface. MC simulation is used to understand the adsorption patterns of lawsone compounds on metal surfaces. The organic inhibitor L-NH2 has better performance as a corrosion inhibitor for mild steel in neutral or protonated conditions.</p>
Original ResearchChemistryLawsone, Substituents, DFT, MP2, Monte Carlo, Corrosion inhibitorscorrosionmaterial sciencesnatural productSaprizal HadisaputraLalu Rudyat Telly Savalas
Copyright (c) 2023 Saprizal Hadisaputra, Lalu Rudyat Telly Savalas
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2023-06-142023-06-141371137110.46481/jnsps.2023.1371The Efficiency of the K-L Estimator for the Seemingly Unrelated Regression Model: Simulation and Application
https://journal.nsps.org.ng/index.php/jnsps/article/view/1514
<p>This paper considers the Ridge Feasible Generalized Least Squares Estimator (RFGLSE), Ridge Seemingly Unrelated Regression R<sub>SUR</sub> and proposes the Kibria-Lukman KL<sub>SUR</sub> estimator for the parameters of the Seemingly Unrelated Regression (SUR) model when the regressors of the models are collinear. A simulation study was conducted to compare the performance of the three different types of estimators for the SUR model. Different correlation levels (0.0, 0.1, 0.2, ..., 0.9) among the independent variables, sample sizes replicated 10000 times and contemporaneous error correlation (0.0, 0.1, 0.2, ..., 0.9) among the equations were assumed for the simulation study. The efficiency of the three (RFGLSE, R<sub>SUR</sub>, and KL<sub>SUR</sub> estimators for SUR, when the predictors are correlated, was investigated using the Trace Mean Square Error (TMSE). The results showed that the KL<sub>SUR</sub> estimator outperformed the other estimators except for a few cases when the sample size is small.</p>
Original ResearchMathematical, Computer & Statistical SciencesMulticollinearityRidge feasible generalized least squares estimatorSeemingly Unrelated RegressionTrace Mean Square ErrorK-LSURStatisticsApplied StatisticsEconometricsOluwayemisi Oyeronke AlabaB. M. Golam Kibria
Copyright (c) 2023 Oluwayemisi Oyeronke Alaba, B. M. Golam Kibria
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2023-06-142023-06-141414141410.46481/jnsps.2023.1514Collocation Method for the Numerical Solution of Multi-Order Fractional Differential Equations
https://journal.nsps.org.ng/index.php/jnsps/article/view/1075
<p>This study presents a collocation approach for the numerical integration of multi-order fractional differential equations with initial conditions in the Caputo sense. The problem was transformed from its integral form into a system of linear algebraic equations. Using matrix inversion, the algebraic equations are solved and their solutions are substituted into the approximate equation to give the numerical results. The effectiveness and precision of the method were illustrated with the use of numerical examples.</p>
Original ResearchMathematical, Computer & Statistical SciencesDifferential equationFractional derivativesApproximate solutionPower seriesFRACTIONAL CALCULUSGaniyu AjileyeAdewale James
Copyright (c) 2023 G. Ajileye, A. A. James
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2023-06-112023-06-111075107510.46481/jnsps.2023.1075Model Fitness and Predictive Accuracy in Linear Mixed-Effects Models with Latent Clusters
https://journal.nsps.org.ng/index.php/jnsps/article/view/1437
<p>In clustered data, observations within a cluster show similarity between themselves because they share common features different from observations in the other clusters. In a given population, different clustering may surface because correlation may occur across more than one dimension. The existing multilevel analysis techniques of the primal linear mixed-effect models are limited to natural clusters which are often not realistic to capture in real-life situations. Therefore, this paper proposes dual linear mixed models (DLMMs) for modeling unobserved latent clusters when such are present in data sets to yield appreciable gains in model fitness and predictive accuracy. The methodology explored the development and analysis of the dual linear mixed models (DLMMs) based on the derived latent clusters from the natural clusters using multivariate cluster analysis. A published data set on political analysis was used to demonstrate the efficiency of the proposed models. The proposed DLMMs have yielded minimum values of the models' assessment criteria (Akaike information criterion, Bayesian information criterion, and root mean squared error), and hence, outperformed the classical PLMMs in terms of model fitness and predictive accuracy.</p>
Original ResearchMathematical, Computer & Statistical SciencesClustered dataPrimal and dual clustersLinear mixed-effects modelsModel fitnessPredictive accuracyStatisticsWaheed B. YahyaYusuf BelloAbdulrazaq AbdulRaheem
Copyright (c) 2023 Yusuf Bello, Waheed Yahya, B., Professor
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2023-06-112023-06-111437143710.46481/jnsps.2023.1437Numerical investigation of nonlinear radiative flux of non-Newtonian MHD fluid induced by nonlinear driven multi-physical curved mechanism with variable magnetic field
https://journal.nsps.org.ng/index.php/jnsps/article/view/1435
<p>This paper discusses two-dimensional heat flow of an incompressible non-Newtonian hydromagnetic fluid over a power-law stretching curved sheet. The energy equation of the flow problem considers a radiative flux influenced by viscous dissipation and surface frictional heating. Lorentz force and Joule heating are taken in the consequence of applied variable magnetic field satisfying solenoidal nature of magnetism. The governing equations are reduced to boundary-layer regime using dimensionless quantities and the resulting PDEs are converted into ODEs by suitable similarity variables. The flow fields; velocity and temperature are computed numerically by implementing Keller-Box shooting method with Jacobi iterative technique. Error analysis is calculated to ensure solutions' convergence. Interesting flow parameters are examined and plotted graphically. Results show that velocity is increased for large number of fluid rheology and opposite effects are recorded for increasing curvature, Lorentz force, and stretching power. Flow past a flat and curved surfaces are substantial in validation of this present work.</p>
Original ResearchMathematical, Computer & Statistical SciencesPower-law, cross fluid, radiation, dissipation, MHD, curved surface, joule heatingFluid mechanics, Thermodynamics, Hydrodynamics, and Numerical computationKehinde SanniAdeshola AdediranAliu Tajudeen
Copyright (c) 2023 Kehinde Sanni, Adeshola Dauda Adediran, Aliu Olaniyi Tajudeen
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2023-06-112023-06-111435143510.46481/jnsps.2023.1435Numerical Analysis of Fractional-Order Dynamic Dengue Disease Epidemic in Sudan
https://journal.nsps.org.ng/index.php/jnsps/article/view/1464
<p>The main idea of this work is numerical simulation and stability analysis for the fractional-order dynamics of the dengue disease outbreak in Sudan. This research uses a computer technique based on the Adams-Bashforth approach to numerically resolve a fractional-order dengue epidemic in Sudan. Analyses of numerical and dynamic stability show that the fractional-order dengue fever model is sensitive to initial conditions for those parameters. Therefore, the parameters’ values are critical in establishing how many individuals will get better from their sickness and how many will become ill. The proposed method is effective in providing an illustration of the solution’s dynamics over a very long horizon of time, which is crucial for making accurate predictions about the spread of dengue in Sudan. In addition, this method can be utilized to assess the efficacy of various intervention strategies and inform public health policies aimed at reducing the burden of dengue fever in Sudan. It can also assist in identifying areas most susceptible to dengue infestations and prioritizing disease control resources.</p>
Original ResearchMathematical, Computer & Statistical SciencesA fractional Caputo-Fabrizio; Prediction; simulation; Dengue.modellingsimulationfractional operatornumerical solutionFathelrhman EL Guma Ossama M. BadawyMohammed BerirMohamed A. Abdoon
Copyright (c) 2023 Fathelrhman EL Guma, Ossama M. Badawy, Mohammed Berir, Mohamed A. Abdoon
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2023-05-282023-05-281464146410.46481/jnsps.2023.1464Non-Intrusive Load Monitoring (NILM), Interests and Applications
https://journal.nsps.org.ng/index.php/jnsps/article/view/1208
<p>In developing effective energy management mechanisms, new concepts have been developed to provide new approaches. Non-intrusive load monitoring (NILM) is an approach that was originally developed to allow the occupants of a room to identify the contribution of each appliance to the total electricity consumption of the room through a single point measurement device. The aim is to provide customers with information that will enable them to act as `` ` consum'actors", i.e., people who undertake to change their electricity consumption habits for an objective cause. The progress of artificial intelligence in its various forms (machine learning, big data, internet of things) have greatly contributed to increase the interest of NILM among researchers in different fields. Indeed, some of them are adapting this concept to research areas such as water, transport, health, the environment and agriculture. In this context, applications in these fields have been developed to show the potential and benefits of using this approach. In addition to presenting non-intrusive load monitoring (NILM) in its general framework, this article presents the interests and applications of this approach in various fields.</p>
Special Issue : 3rd biennial AScIN conference OAU, NigeriaPhysics & AstronomyNon-intrusive load monitoring (NILM)InterestsApplicationsPower consumptionEnergy efficiencyEnergyElectricityLeonce Wehnelt TOKAMSanoussi S. OURO-DJOBO
Copyright (c) 2023 Leonce Wehnelt TOKAM, Sanoussi S. OURO-DJOBO
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2023-05-272023-05-271208120810.46481/jnsps.2023.1208Approximate solution of space fractional order diffusion equations by Gegenbauer collocation and compact finite difference scheme
https://journal.nsps.org.ng/index.php/jnsps/article/view/1368
<p>In this paper, approximation of space fractional order diffusion equation are considered using compact finite difference technique to discretize the time derivative, which was then approximated via shifted Gegenbauer polynomials using zeros of (N - 1) degree shifted Gegenbauer polynomial as collocation points. The important feature in this approach is that it reduces the problems to algebraic linear system of equations together with the boundary conditions gives (N + 1) linear equations. Some theorems are given to establish the convergence and the stability of the proposed method. To validate the efficiency and the accuracy of the method, obtained results are compared with the existing results in the literature. The graphical representation are also displayed for various values of \beta Gegenbauer polynomials. It can be observe in the tables of the results and figures that the proposed method performs better than the existing one in the literature.</p>
Original ResearchMathematical, Computer & Statistical SciencesCaputo derivativefractional diffusion equationGegenbauer polynomialCompact finite difference method (CFDM)Numerical AnalysisComputational MathematicsFractional diffusion equationKazeem IssaSteven Ademola OlorunnisolaTajudeen AliuAdeshola Adeniran Dauda
Copyright (c) 2023 K. Issa, A. S. Olorunnisola, O. T. Aliu, A. D. Adeshola
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2023-05-222023-05-221368136810.46481/jnsps.2023.1368Evaluation of ANFIS Predictive Ability Using Computed Sediment from Gullies and Dam
https://journal.nsps.org.ng/index.php/jnsps/article/view/1028
<p>The study proposed an Adaptive Neuro-Fuzzy Inference Systems (ANFIS) model capable of predicting sediment deposited in a dam and sediment loss-in-transit (SLIT) using the potential of a formulated mathematical relation. The input parameters consist of five members viz: the rainfall, the slope, the particle size, the velocity, and the computed total volume of sediment exited from two prominent gullies for 2017, 2018, and 2019. The outputs are the total volume of sediment deposited at the adjoining Ikpoba dam for 2017, 2018, and 2019, respectively. The Ordinary Least Square (OLS) regression model on sediment volume retained all covariates with p<0.05, explaining 93.8% of the variability in the dataset. The multicollinearity effect on the dataset was assessed using the Variance Inflation Factor (VIF) which was found not to pose a problem for (VIF<5). The model was validated using the (MSE), the (MAE), and the correlation coefficient (r). The best prediction was obtained as: (RMSE = 0.0423; R2 = 0.947). The predicted volume of sediment was 842,895.8547m3 with an error of -0.3295344% and the predicted volume of SLIT was 57,787.98m3 which is an indication that ANFIS performs satisfactorily in predicting sediment volume for the gullies and the dam respectively</p>
Review ArticleEarth SciencesANFIS, Gully Erosion, Ikpoba Dam, SedimentationSurveying/GeomaticsStephen Olushola OladosuAlfred Sunday Alademomi James Bolarinwa OlaleyeJoseph Olalekan OlusinaTosin Julius Salami
Copyright (c) 2023 Stephen Olushola Oladosu, Alfred Sunday Alademomi , James Bolarinwa Olaleye, Joseph Olalekan Olusina, Tosin Julius Salami
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2023-05-212023-05-211028102810.46481/jnsps.2023.1028Pre-functions and Extended pre-functions of Complex Variables
https://journal.nsps.org.ng/index.php/jnsps/article/view/1427
<p>Pre-functions are functions that possess a sequence $\{f_{n}(z,\beta)\}$ which tends to one of the elementary functions as $n$ tends to infinity and $\beta$ tends to 0. The main objective of this paper is to broaden the scope of pre-functions from functions of a real variable to functions of a complex variable by introducing pre-functions of a complex variable. We have analyzed the pre-functions of a complex variable for their properties. The pre-Laguerre, pre-Bessel and pre-Legendre polynomials of a complex variable have been obtained as special cases. Graphs have been used to visualize complex pre-functions.</p>
Original ResearchMathematical, Computer & Statistical Sciencespre-exponential functions, pre-trigonometric functions, pre-hyperbolic functions, Extended pre-functions.30G35Thirumalai AMuthunagai KRitu Agarwal
Copyright (c) 2023 Thirumalai A, Muthunagai K, Ritu Agarwal
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2023-05-212023-05-211427142710.46481/jnsps.2023.1427Generation of Electricity From a Hydraulic Turbine in the Djonou River (Benin)
https://journal.nsps.org.ng/index.php/jnsps/article/view/1263
<p>The shortage of electricity in rural areas despite the hydraulic potential they possess is becoming a challenge for Benin. To date, nearly 140,000 people spread over the 42 lakeside villages of this country live in energy inaccessibility, insecurity and poverty. To overcome this situation, the present study is therefore interested in the production of electrical energy on an experimental basis in low water periods thanks to an Archimedean screw turbine which operates at low flow rates and height of fall on the river. Djonou located in southern Benin a few kilometers from the University of Abomey-Calavi. The geometrical and hydraulic parameters of the screw were therefore determined and the device was modeled using Autocard software. A prototype was then made with local recycled materials and tested on the river. The screw specifications indicate an inside and outside radius of 0.072 m and 0.135 m. The length of the screw was set at 0.46 m for a blade radius estimated at 0.137 m. The number of screw blades is equal to 2 with a flow rate of 0.049 $ m^{3}/s $. The inclination angle of the screw is $25^{\circ}$. The device on the experimental site produces a voltage of 16 V and provides a current of about 0.12 A which can power a 2 W lamp. This performance of the prototype made on a small scale is a reliable indicator of the optimal use of this technology in the national hydraulic network of Benin to supply populations with electrical energy.</p>
Special Issue : 3rd biennial AScIN conference OAU, NigeriaPhysics & AstronomyHydroelectricity, flow, experimentation, energy inaccessibility, Archimedean screw, low water period.Renewable EnergyMahouton Justine Carine ADJASSA Gabin KOTO N'GOBI Hagninou Elagnon Venance DONNOUClément Adéyèmi KOUCHADE Basile Bruno KOUNOUHEWA
Copyright (c) 2023 Mahouton Justine Carine ADJASSA, Gabin KOTO N'GOBI, Hagninou Elagnon Venance DONNOU, Clément Adéyèmi KOUCHADE, Basile Bruno KOUNOUHEWA
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2023-05-212023-05-211263126310.46481/jnsps.2023.1263Theoretical Study on 10C Elastic Scattering Cross Sections Using Different Cluster Density Distributions and Different Potentials
https://journal.nsps.org.ng/index.php/jnsps/article/view/1392
<p>Elastic scattering cross sections are a fundamental aspect of nuclear physics research, and studying the cross sections of various nuclei can provide important insights into the behavior of nuclei. In this study, the elastic scattering cross sections of <sup>10</sup>C projectile by <sup>27</sup>Al, <sup>58</sup>Ni, and <sup>208</sup>Pb target nuclei are analyzed. The aim of this study is to investigate the cluster structure of <sup>10</sup>C and the sensitivity of the elastic scattering cross sections to different potentials. To achieve this objective, the double folding optical model and a simple cluster approach are used to analyze the cross sections. The real part of the optical potential is obtained by folding two different effective interactions, Michigan-3-Yukawa (M3Y) and JeukenneLejeune-Mahaux (JLM), with four different cluster density distributions of the <sup>10</sup>C nucleus: <sup>6</sup>Be + \alpha, <sup>9</sup>B + <em>p</em>, <sup>8</sup>Be + <em>p </em>+ <em>p</em>, and \alpha + \alpha + <em>p </em>+ <em>p</em>. The imaginary part is taken to be a Woods-Saxon phenomenological form. The sensitivity of the elastic scattering cross sections to different potentials is assessed by comparing the results obtained using different potentials. The cluster structure of <sup>10</sup>C is validated by comparing the theoretical results with experimental data. The results show that the cross sections are sensitive to the choice of potential used and that the cluster structure of <sup>10</sup>C is validated. The theoretical results show reasonable agreement with the experimental data.</p>
Original ResearchPhysics & AstronomyElastic scattering, density distribution, Optical model, cluster model.Nuclear elastic scattering calculations using double folding modelSunday OlorunfunmiArmand BahiniAdenike Olatinwo
Copyright (c) 2023 Sunday Olorunfunmi, Armand Bahini, Adenike Olatinwo
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2023-05-212023-05-211392139210.46481/jnsps.2023.1392Thermal instability of rotating Jeffrey nanofluids in porous media with variable gravity
https://journal.nsps.org.ng/index.php/jnsps/article/view/1366
<p>It is investigated how changes in gravity affect the thermal instability rotating Jeffrey nanofluids in porous media. Along with the Galerkin method and normal mode approach, the Darcy model is used. The distinct variable gravity parameters taken in this paper are: h(z)=z<sup>2</sup>-2z, h(z)=-z<sup>2</sup>, h(z)=-z and h(z)=z and their effects on the Jeffrey parameter, Taylor number, moderated diffusivity ratio, porosity of porous media, Lewis number and nanoparticle Rayleigh number on stationary convection have been scrutinized and graphically shown. Our finding demonstrates that varying gravity parameter h(z)=z<sup>2</sup>-2z has more stabilising impact on stationary convection. We have also discovered the necessary condition for overstability in the instance of oscillatory convection for this problem.</p>
Original ResearchPhysics & AstronomyMathematical, Computer & Statistical Sciencesnanofluid, variable gravity, porous medium, Galerkin method, rotationMathematical SciencePushap Lata SharmaDeepak BainsPankaj Thakur
Copyright (c) 2023 Pushap Lata Sharma, Deepak Bains, Pankaj Thakur
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2023-05-202023-05-201366136610.46481/jnsps.2023.1366Study of the passivation of defects in the perovskite cell: application to Sahelian climate conditions
https://journal.nsps.org.ng/index.php/jnsps/article/view/1250
<p>This article is devoted to the study of the performance of the photovoltaic cell based on perovskite (MAPbI<sub>3</sub>) in real conditions of sub-Saharan Africa. A model of this cell has been made taking into account the integration of defects at the interfaces. After a study of the sensitivity of these defects, a passivation layer was introduced at the interface to improve the performance of the cell. The influence of temperature and irradiance on the performance of perovskite cells was studied on the one hand with defects at the interfaces and on the other hand with the integration of a passivation layer of defects. The results show a decrease of the performance ratio for the non-passivated cell due to the defects present at the interfaces of the said cell. The models developed under SCAPS-1D were validated by applying it to a real module found in the literature under the same conditions. The performance calculation shows a satisfactory qualitative and quantitative agreement. The results relative to the performance ratios obtained for the simulated models show that perovskite is on the right track for a potential future candidacy to the most suitable technologies for sub-Saharan Africa.</p>
Special Issue : 3rd biennial AScIN conference OAU, NigeriaPhysics & AstronomyModeling, perovskite solar cells, interface defects, performance ratioRenewable EnergyEssodossomondom Anate N’Detigma KataHodo-Abalo SamahAmadou Seidou Maiga
Copyright (c) 2023 Essodossomondom Anate, N’Detigma Kata, Hodo-Abalo Samah, Amadou Seidou Maiga
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2023-05-142023-05-141250125010.46481/jnsps.2023.1250Solving fractional variable-order differential equations of the non-singular derivative using Jacobi operational matrix
https://journal.nsps.org.ng/index.php/jnsps/article/view/1221
<p>This research derives the shifted Jacobi operational matrix (JOM) with respect to fractional derivatives, implemented with the spectral tau method for the numerical solution of the Atangana-Baleanu Caputo (ABC) derivative. The major aspect of this method is that it considerably simplifies problems by reducing them to ones that can be solved by solving a set of algebraic equations. The main advantage of this method is its high robustness and accuracy gained by a small number of Jacobi functions. The suggested approaches are applied in solving non-linear and linear ABC problems according to initial conditions, and the efficiency and applicability of the proposed method are proved by several test examples. A lot of focus is placed on contrasting the numerical outcomes discovered by the new algorithm together with those discovered by previously well-known methods.</p>
Original ResearchMathematical, Computer & Statistical SciencesFDEs; Non-singular derivative; Variable order; Operational matrix.numericalM. BasimN. SenuA. AhmadianZ. B. IbrahimS. Salahshour
Copyright (c) 2023 M. Basim, N. Senu, A. Ahmadian, Z. B. Ibrahim
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2023-05-052023-05-051221122110.46481/jnsps.2023.1221Tuning the optical properties and some surface structure of Cd-O thin film electrodeposited by two-electrode: An effect of Cobalt incorporation
https://journal.nsps.org.ng/index.php/jnsps/article/view/1222
<p>The tuning of optical and dielectric parameters, structural and microstructural properties of CdO synthesized via a solution growth two-electrode cell arrangement under ambient environment, with the incorporation of Co ion into its matrix was investigated. The energy band gaps of the films was estimated in the range of 1.69 eV</=Eg</= 1.96 eV. The extinction coefficient, k for all the samples decreases as the incident photon energy increases. The films exhibit considerably high optical conduction across the photon energy with estimated power of 10<sup>13</sup> (Omega m)<sup>-1</sup>. The elemental composition of the samples was determined using the energy dispersive x-ray spectrometry technique. The micrograph images from scanning electron microscopy technique shown that the films are polycrystalline and well-adhered to the substrates with their crystal grains evenly dispersed across the substrates’ surface. The x-ray diffraction analysis confirmed that the deposited films are of polycrystalline in nature. The films show preference for orientation along the (111) plane.</p>
Special Issue : 3rd biennial AScIN conference OAU, NigeriaPhysics & AstronomyPolycrystallinesolar cellelectrochemical depositiondirect band gaptransparent conducting oxideCondensed Matter PhysicsSolid State PhysicsMaterials ScienceRafiu Adewale BusariEzekiel OmotosoLukman O. AnimasahunSaheed Adekunle AdewinbiEmmanuel O. AdewumiComfort T. FamorotiBidini A. TaleatuAdeniyi Y. Fasasi
Copyright (c) 2023 Rafiu Adewale Busari, Ezekiel Omotoso, Lukman O. Animasahun, Saheed Adekunle Adewinbi, Emmanuel O. Adewumi, Comfort T. Famoroti, Bidini A. Taleatu, Adeniyi Y. Fasasi
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2023-05-022023-05-021222122210.46481/jnsps.2023.1222A DFT study of optoelectronic, elastic and thermo-electric properties of the double perovskites Rb2SeX6 (X=Br,Cl)
https://journal.nsps.org.ng/index.php/jnsps/article/view/1418
<p>Thermo-electric (TE) material applications reduce reliance on traditional energy resources by converting heat to electric energy. We have studied, for the first time, the thermo-electric properties of Rb<sub>2</sub>SeX<sub>6 </sub>(X=Br,Cl). Using norm-conserving pseudo potentials in a plane wave basis set of Quantum Espresso code, the optoelectronic, elastic and thermo-electric properties of Rb<sub>2</sub>SeX<sub>6</sub> (X=Br,Cl) have been investigated using density functional theory. Generalized Gradient Approximation of Perdew Burke Ernzerhof (GGA-PBE) and Generalized Gradient Approximation of Perdew Burke Ernzerhof adapted for Solid (GGA-PBESol) exchange correlation functionals were employed in all calculations. The band structure plots suggest that the studied double perovskites have indirect band gaps. Rb<sub>2</sub>SeBr<sub>6</sub> band gap values of 1.7574/ 1.569 eV (using GGA-PBE/PBEsol) are remarkably similar to that of two effective inorganic/organic perovskites FAPbI3 and MAPbI3 . Maximum peaks generated from refractive index results indicate possible solar cell uses of the materials because they are in the visible and ultraviolet ranges. The results of other optical properties such as absorption coefficients, electron energy loss, conductivity, and reflectivity concludes that Rb<sub>2</sub>SeX<sub>6</sub> (X=Br,Cl) have good values for electron generation, high potential for applications in the optoelectronic industry and are semiconductor in nature. The calculated shear anisotropy values of Rb<sub>2</sub>SeBr<sub>6</sub>/Cl<sub>6</sub> are 3.09/1.71, suggesting that they are isotropic materials. With calculated Poisson’s ratio of 0.32 and 0.26, the materials are predicted to be ductile in nature. The two materials are appropriate for thermo-electric applications since their thermal to electrical conductivity ratio are small (the order of 10<sup>-5</sup>). The calculated minimum values of Seebeck coefficient values of 0.198×10<sup>3</sup> / 0.166 ×10<sup>3</sup> (mV/K) at 750 K, for Rb<sub>2</sub>SeBr<sub>6</sub>/Cl<sub>6</sub> are positive, indicating that they have p-type conduction. Figure of merit values at all temperature range considered are greater than one (ZT > 1) for both Rb<sub>2</sub>SeBr<sub>6</sub> and Rb<sub>2</sub>SeCl<sub>6</sub>, suggesting that they are good thermo-electric materials. The results of the calculations provide the basis for the industrial application of Rb2SeBr6/Cl6 as solar cells.</p>
Original ResearchPhysics & AstronomyDouble perovskiteopto-electronic propertiesElastic propertiiesSeebeck coefficientsFigure of meritDFTPhysicsWasiu YahyaA. A. YahayaA. A. AdewaleA. A. SholagberuN. K. Olasunkanmi
Copyright (c) 2023 W. A. Yahya, A. A. Yahaya, A. A. Adewale, A. A. Sholagberu, N. K. Olasunkanmi
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2023-05-022023-05-021418141810.46481/jnsps.2023.1418On Bivariate Nadarajah-Haghighi Distribution derived from Farlie-Gumbel-Morgenstern copula in the Presence of Covariates
https://journal.nsps.org.ng/index.php/jnsps/article/view/871
<p>An important alternative distribution to the Weibull, generalized exponen-<br>tial and gamma distributions that is used in survival analysis is the Nadarajah-<br>Haghighi exponential distribution. Similar to the Weibull, generalized exponen-<br>tial and gamma distributions, the Nadarajah-Haghighi exponential distribution<br>is an extension of the well known exponential distribution. In this paper, a copula<br>function commonly used to model very weak linear dependence was used to intro-<br>duced a bivariate Nadarajah-Haghighi distribution. The joint survival function,<br>joint probability density function and joint cumulative distribution were given<br>in closed form. Bayesian method of estimation was used to estimate the model<br>parameters considering the presence of right censoring and covariates. Posterior<br>summaries of interest were obtained via standard Markov Monte Carlo (MCMC )<br>technique. Two real data sets were used to illustrate the importance and flexi-<br>bility of the bivariate model in comparison with some competing models. It was<br>observed that, the bivariate Nadarajah-Haghighi distribution provides a better flt<br>than bivariate exponential, bivariate Weibull, bivariate generalized exponential<br>and bivariate modified Weibull distributions.</p>
Original ResearchMathematical, Computer & Statistical SciencesExponential Distribution, Nadarajah-Haghighi Distribution, Bivariate Models and Copula Function.StatisticsYakubu AliyuUmar Usman
Copyright (c) 2023 Yakubu Aliyu, Umar Usman
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2023-05-012023-05-0187187110.46481/jnsps.2023.871Numerical Simulation of Nonlinear and Non-Isothermal Liquid Chromatography for Studying Thermal Variations in Columns Packed with Core-Shell Particles
https://journal.nsps.org.ng/index.php/jnsps/article/view/1350
<p>A high-resolution flux-limiting semi-discrete finite volume scheme (HR-FVS) is applied in this study to numerically approximate the nonlinear and non-isothermal flow of one-dimensional lumped kinetic model (1D-LKM), for a fixed-bed column loaded with core-shell particles. The developed model comprise a system of convection-dominated partial differential for mass and energy balances in the mobile phases coupled with differential equation and algebraic equation in the stationary phase. The solution of the model equations is obtained by utilizing a HR-FVS, the scheme has second-order accuracy even on the grid coarse and its explicit nature has the potential to resolve the arisen sharp discontinuities in the solution profiles. A second-order total variation diminishing (TVD) Runge-Kutta technique is used to solve the system of ODEs in time. Several forms of a single-solute mixture are produced to investigate the influences of the fractions of core radius on thermal waves and concentration fronts. Moreover, a particular criterion is introduced for analyzing the performance of the underlying process and to identify the optimal parameter values of the fraction of core radius.</p>
Original ResearchMathematical, Computer & Statistical SciencesNon-isothermal chromatography, Non-linear isotherm, One-dimensional lumped kinetic model, High-resolution schemeComputational fluid dynamicsAbdulaziz G. AhmadNnamdi F. OkechiDavid U. UcheAbdulwasiu O. Salaudeen
Copyright (c) 2023 Abdulaziz G. Ahmad, Nnamdi F. Okechi, David U. Uche, Abdulwasiu O. Salaudeen
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2023-04-242023-04-241350135010.46481/jnsps.2023.1350An integral approach for complete migration from a relational database to MongoDB
https://journal.nsps.org.ng/index.php/jnsps/article/view/1089
<p>Today, computing has become an obligation in the lives of individuals and institutions alike. This magical sector uses and develops very rich, important, and sensitive tools and solutions, which make everyone's life easier. Computers with their tools have become indispensable and they have transformed the world into a small town. These tools revolve around data, the type, nature, and size of which continually increases up to zeta bytes of storage capacity, thus creating BigData. Considering that Relational databases present difficulties in the management of BigData, and Knowing that companies want to keep their data accumulated over decades of exercises and studies on the market, and also taking into account the cost impact if they kept both systems in terms of software, technical support and user training; therefore it is legitimate to find a reliable way to migrate their data from the relational system to a NoSQL system, which designed specifically to handle BigData. In this optic, several studies and approaches have been developed, but they present a lack or weaknesses in the treatment of the main components of the database, which we are going to deal with in our new and integrated approach to migration from the relational database system to MongoDB as a NoSQL system. In this article, we will present our contribution by developing a complete concept of our approach, starting with an introduction, which will be followed by a discussion of what other researchers have done in this direction, then we move on to a phase of analysis and modeling to develop the models and meta-models of the two systems: source and destination, also during this section we also present our analysis and modeling methodology, to present our global approach which divides its treatment into three axes, each of which processes a part of the RDBMS with a particular nature of data: data stored in tables, data carried on the structure of the RDBMS and data coming from the semantics of relational databases. The overall architecture of our approach, which we named ''TMSDRDND'', is formed by two layers: ''TSRSNLayer'' which deals with the transformation of the structure and the transfer of semantic data, and the ''MDRSNLayer'' layer, Which takes care of data migration using an ETL to be developed according to a specific concept and architecture and exploiting the results of the first layer.</p>
Review ArticleMathematical, Computer & Statistical SciencesData Migration, Database Transformation, NoSQL, Big Data, Data, ETL, approachDataBaseBigDataNosqlMigrationTransformationMongoDBAbdelhak ErrajiAbderrahim MaizateMohamed Ouzzif
Copyright (c) 2023 Abdelhak Erraji, Abderrahim Maizate, Mohamed Ouzzif
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2023-04-242023-04-241089108910.46481/jnsps.2023.1089Solar Energy Storage by Fuel Cell Technology at Abomey-Calavi (Benin)
https://journal.nsps.org.ng/index.php/jnsps/article/view/1264
<p>West Africa has a great amount of sunshine power, varying between 5 kWh.m^{-2}.day^{-1} and 7 kWh.m^{-2}.day^{-1}. This power constitutes high energy source in the region. However, several locations in that area have no access to energy because of the lack of suitable technology and projects exploiting the source. The fundamental problem related to sun power or to renewable energies in general is the lack of efficient technology for energy storage. Batteries are generally used for this storage, but once charged, the excess of the energy from the solar photovoltaic panels (PV) is lost. Therefore, it is very important to find a system to recover the excess in order to optimize its use. In this context, hydrogen is considered a very promising candidate to fulfill this function and could become a highly developed energy vector in the future. The very numerous works undertaken over the past decade for the production of electricity by hydrogen fuel cells bear witness to this. The objective of this study is to test a more reliable solar energy storage system by using fuel cell technology. To achieve this, three steps have been necessary: (i) make an electrolyser using materials, (ii) produce hydrogen using a system of PV panels and (iii) convert the hydrogen produced into electricity through a fuel cell. The results obtained indicate a production of 0.020 m^3 of hydrogen after 150 min with a yield of 85.86%. The production of electricity by a 2 V fuel cell gives an efficiency of 0.0042%. Even if this value is low, a part of the lost energy has been recovered. In view of these results, the improvement of the device for converting chemical energy into electricity deserves to be deeply explored in West Africa.</p>
Special Issue : 3rd biennial AScIN conference OAU, NigeriaPhysics & AstronomyRenewable Energy, storage, solar energy, electrolysis, hydrogen, fuel cell, BeninRenewable EnergyOdilon Joseph TOWANOUHagninou Elagnon Venance DonnouGabin Koto N’GobiAugustin Enonsi LeodeBasile Kounouh´ewa
Copyright (c) 2023 Odilon Joseph TOWANOU, Hagninou Elagnon Venance Donnou, Gabin Koto N’Gobi, Augustin Enonsi Leode, Basile Kounouh´ewa
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2023-04-222023-04-221264126410.46481/jnsps.2023.1264Annual Effective Dose and Excess Lifetime Cancer Risk due to Ingestion and Inhalation of Radon in Groundwater of Bosso Community Minna, North-Central Nigeria
https://journal.nsps.org.ng/index.php/jnsps/article/view/896
<p>Radon in potable water has become an issue of public health concern, especially when consumed or used directly from source for domestic purposes without any pre-treatment. In this study, <sup>222</sup>Rn concentration in 22 water samples collected from 2 groundwater sources (open wells, 12 samples and boreholes, 10 samples) in Bosso town, North central Nigeria were measured using Durridge RAD-7 radon detector with RAD-H<sub>2</sub>O accessories. <sup>222</sup>Rn concentrations in open wells varied from 2.1±0.7 to 27.9±2.5 Bq L<sup>-1</sup> with a mean of 10.2±1.5 Bq L<sup>-1</sup>, while that in boreholes ranged from 2.8±1.1 to 39.2±1.5 Bq L<sup>-1</sup> with a mean value of 14.3±1.7 Bq L<sup>-1</sup>. These values are lower than the 100 Bq L<sup>-1 </sup>upper limit proposed by the European Union Commission, above which any practical intervention may be necessary. Mean annual committed effective dose to adults, children and infants from ingestion of water were 74.64, 71.58 and 53.17 \muSv y<sup>-1</sup> respectively for the open wells and 104.24, 99.96 and 74.26 \muSv y<sup>-1</sup> respectively for borehole water samples. Mean whole body dose due to ingestion and inhalation of waterborne radon from open wells and boreholes are 27.56 and 38.48 \muSv y<sup>-1</sup> respectively, which are below the reference level of 0.1 mSv y<sup>-1</sup> for potable water recommended by the World Health Organization for public safety. The excess lifetime cancer risk were 0.10 × 10<sup>-3</sup> for the open wells and 0.13 × 10<sup>-3</sup> for the boreholes, which are lower than the world safety limit 0.29 × 10<sup>-3</sup>. Water from the two groundwater sources investigated is therefore fit for consumption and other domestic usage from the point of view of radiation protection. </p>
Original ResearchPhysics & Astronomy222Rn concentration, groundwater, Bosso community, RAD-7 radon detector, Committed effective dose, ELCR, NigeriaPhysicsWater resource engineeringMatthew Tikpangi KoloOyeleke OlarinoyeSimon Olonkwoh SalihuHyginus Anayo UgwuanyiPaul OnucheOpeyemi FaladeNwachukwu Chibueze
Copyright (c) 2023 Matthew Tikpangi Kolo, Oyeleke Olarinoye, Simon Olonkwoh Salihu, Hyginus Anayo Ugwuanyi, Paul Onuche, Opeyemi Falade, Nwachukwu Chibueze
https://creativecommons.org/licenses/by/4.0
2023-04-192023-04-1989689610.46481/jnsps.2023.896