International Journal of Science for Global Sustainability
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Structural and Electrical Properties of Fluorine doped Tin oxide (FTO) Thin Film Deposited by Spin Coating Technique
Get PDFFluorine-Doped Tin OxideTO) thin films were deposited on a glass substrate using the spin coating technique and then annealed in both open air and nitrogen environments at temperatures between 500oC and 600°C. This study examined how annealing temperature affects the structural and electrical properties of the films. X-ray diffraction (XRD) analysis showed that the films had a polycrystalline structure, predominantly with the (110) plane. As the annealing temperature is increased, the crystal size also increased, leading to lower dislocation density and higher electron mobility. The resistivity of the films decreased with higher annealing temperatures, reaching its lowest value at 600°C. These findings indicate that annealing temperature is crucial for optimizing the structural and electrical properties of FTO thin films made via spin coating. The optimal annealing conditions were found to be 600°C in open air, resulting in a resistivity of 2.47×10-3 Ω-cm, sheet resistance of 1.08×10-2 Ω/square, the largest grain size of 18.41 nm, and the lowest values for dislocation density (2.95×1015 lines/cm2) and micro-strain (1.97×10-3)
Common L-Fuzzy Fixed Point Results for Contractive L-Fuzzy Maps in F-Metric Space
Get PDFIn this paper, we establish an -fuzzy fixed point theorem for generalized contractive -fuzzy mappings in the context of an -complete -metric space. We also provide consequences and examples to support the main findings
Towards Enhancing Energy Consumption and Time Complexity of Combinatorial Algorithms for Solving the Knapsack Problem
Get PDFThe increasing demand for energy-efficient and time-optimized computational systems has driven research into combinatorial algorithms, particularly those used to solve the knapsack problem. The knapsack problem is one of the most significant in combinatorial optimization, which involves determining the optimal selection of items to include in a knapsack while adhering to specific constraints, such as weight or profit limits. This study compares the energy consumption and time complexity of the greedy and dynamic programming algorithms applied to this problem. Using power models to measure total energy consumption and execution time, the research reveals that the greedy algorithm is far more efficient, with negligible energy consumption across various scenarios. In contrast, the dynamic programming algorithm, while delivering accurate solutions, consumes more energy and takes longer due to its memory-intensive operations. These findings highlight the need to consider energy and time efficiency in algorithm design, contributing to more sustainable computing practices. Future research will explore larger datasets and focus on instruction-level energy analysis to optimize algorithm performance
Combined effects of Darcy and Viscous Dissipation on Steady Natural Convection flow in a Vertical Tube partially filled with Porous Material with asymmetric thermal boundary conditions
Get PDFThis paper examines the impact of Darcy and Viscous dissipation on the hydrodynamic and thermal behavior of steady natural convection in a fully developed incompressible fluid flowing through a vertical composite tube with asymmetric thermal boundary conditions. The fluid motion in the tube is driven by a temperature gradient resulting from heat applied to the tube wall. The study employs the Brinkman-Darcy extended model to simulate fluid flow for both water and air working fluids. The homotopy perturbation method was chosen to solve the temperature and velocity equations for both clear and porous fluids. This method was selected because it systematically decouples the system and overcomes the limitations associated with small parameters in the commonly used perturbation method. Additionally, the homotopy perturbation approach highlights the interactions between parameters that are hidden in numerical methods. An increase in the Brinkman number enhances both the temperature and velocity profiles of the working fluids. Similarly, increasing the thickness of the porous material can boost the fluid's velocity in the composite vertical tube. A rise in the material's porosity also leads to an increase in fluid velocity
Effects Of Viscous Dissipative Fluid on Couette Flow in A Vertical Channel Due to Newtonian Heating
Get PDFThis article presents the numerical investigation of magnetohydrodynamic (MHD) heat transfer flow of viscous dissipation in vertical channel in the presence of Newtonian heating. The coupled nonlinear dimensional partial differential equations governing the flow are converted into non-dimensional form by using the appropriate dimensionless quantities and parameters Implicit Finite Difference Method (IFMD) was employed in finding the solutions of dimensionless partial differential equations. The expressions of velocity, temperature, skin friction and Nusselt number were obtained numerically and discussed using line graphs. From the outcome of the results, it was concluded that rising the Newtonian heating parameter (γ), Brinkman number (Br), lead to a substantial growth of velocity and temperature. Similarly, as the, Grashof number (Gr) increases, the velocity of the fluid also gets increased. The skin friction gets enlarged with the increase of Grashof number (Gr), Newtonian heating parameter (γ), Brinkman number (Br) and time at .The Nusselt number gets reduced with the increase in Newtonian heating parameter (γ), Brinkman number, and time parameter at and increases at
Insilico Toxicological Assessment and Molecular Docking Investigations of Pesticides Employed used in Sokoto State, Nigeria
Get PDFMany pesticides are associated with severe health implications, and end users are at risk. In silico studies make it easier to quickly perform toxicity for chemicals. The present work was aimed at conducting a survey in Sokoto, Sokoto State Nigeria, to determine the types of pesticides used, and attitudes towards their safe handling. 242 respondents from Sokoto, Sokoto State, were interviewed to collect the information using an indept field survey. Chemical library of pesticides in the study area were developed and the pesticides from the survey were investigated in-silico for absorption, distribution, metabolism, excretion and toxicity (ADMET), drug likeness and toxicity prediction using SwissADME webserver, the target proteins were also predicted using Swiss Target prediction. Molecular docking of the pesticide against their predicted target proteins was done using PyRx and PyMol. Acetylcholinesterase and MAP kinase was selected as target protein for dichlorvos and cypermethrin. The results obtained showed that atrazine, bifenthrin, cypermethrin, dichlorvos, glyphosate, lindane, paraquat and pendimethaline were the pesticides used in Sokoto, Sokoto State. The docking studies show that dichlorvos have lower binding affinity to acetylcholinesterase compared to galantamine a known potent (Alzheimer’s disease) cholinesterase inhibitor drug. The study revealed that all the selected pesticides have good oral bioavailability as they did not violate the Lipinski Rule of five. In conclusion, all the pesticides used in Sokoto were classified as highly toxic to human health
Does Holidays affect the Returns of Stock Markets Prices? An Application of some GARCH and Prophet Models under Varying Error Distributions
Get PDFLogically speaking, financial time series data such as stock price returns is directly or indirectly affected by some factors such as holidays (Valentine’s Day, Father’s Day, etc.). These effects have not been fully studied by researchers. This paper utilizes GJR-GARCH (with dummy variables as holidays) and Prophet models on Nigeria and Chinese stock price returns so that more realistic results and information on how the holidays affect the returns of stock markets will be obtained. Results of the analysis reveal the existence of holiday’s effects on Thursdays (for NSE) and Mondays and Fridays (for CSE) both under Generalized Error Distribution (GED) assumption of innovations. Additionally, no leverage effect was found in the two returns series. Furthermore, the GJR-GARCH model under all the three considered distributions of innovations on the two data sets shows volatility clustering and persistence. Thereafter, evidence from the minimum RMSE and MAE, the GJR-GARCH model under NSE slightly outperformed the Prophet model, while under CSE, the Prophet model performed better than the GJR-GARCH model
Optimization Problem for Deteriorating Items Model with Stock Dependent Demand and Controllable Deterioration Under Two Warehouse Storage Facility
Get PDFIn any inventory and production management, deterioration of physical goods is one of the important factors put into consideration. Therefore, it is very important to control and maintain inventories for decaying items. We considered inventory problem for deteriorating items where demand is stock dependent and deterioration is controllable under two warehouse storage facility, one of the warehouses is owned and the other one is rented. Goods are displayed in both warehouses but demands are met from the rented warehouse until the level of goods get to zero then demands are met from owned warehouse. We derived the optimal inventory management policies for the cases where; the demand is constant function, there is no investment in technology and there is no investment in technology and demand is also constant.  
Predicting Students Academic Performance using Ridge, LASSO and Elastic Net with Efficient Model Selection: A Case Study of Federal University Gusau Nigeria
Get PDFAcademic establishments function in a very demanding and competitive environment. Most of the schools’ face challenges in providing the students with a high-quality education, creating methods for assessing student achievement, analysing performance, and anticipating the needs of their students in the future. This research proposes a sparse regression model that solves the problem of multicollinearity among the six variables. The significant variables that determined the academic performance at graduation were identified, using ridge, LASSO and elastic net. Evaluation metrics and seven selection criteria were used to select the best model. The results show that the age of the student has no impact on the CGPA at graduation. For the training data, the elastic net using SGMASQ significantly suggests better performance in comparison to other models. For the testing data, the elastic net using SGMASQ significantly shows better results in comparison to other models including the training data
An Enhanced Timestamp-Based Security Mechanism to Detect Sybil Attack in vehicle ad hock network (VANETs)
Get PDFWithin the VANET subset of Mobile Ad-hoc Network (MANET), automobiles can communicate with one another via roadside infrastructure or vehicle-to-vehicle communication. However, because nodes move around and topologies might alter at random, there could be a potential of attacks in a VANET. One well-known attack is the Sybil attack, in which the attacker assumes many wrong identities to interfere with the VANET's ability to function. Numerous solutions have been put forth in the literature to identify Sybil attacks. The authors of the recent work have developed a timestamp-based Sybil node discovery method. Every vehicle on the road in VANET is given a unique certificate by RSU, which is included in this work timestamp. We applied the Ad-hoc On-Demand Distance Vector (AODV) Routing protocol and timestamp as a hash function of the public key with addition of the speed of the vehicle in the planned work for node detection and data transmission. In addition, we used the NS2 simulator for Sybil node detection