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Item A Study of Chemically Deposited Barium Titanate (Batio3) Thin Films Doped with Natural Dyes and Their Photovoltaic Applications.(International Journal of Scientific Research in Physics and Applied Sciences, 2023-12) Eze, C. N.; A.I. Onyia; M.N. NnabuchiAbstract - Ternary thin films of BaTiO3 nanostructures were synthesized at 90 0C via the Chemical Bath Deposition (CBD) route under room temperature. They were doped with three natural (local/organic) dyes extracted from Lawsonia inermis leaves, Beta vulgaries roots, and Jatropha curcas leaves and thereafter annealed at 400 0C. doped and as-deposited nanostructures were studied employing XRD, SEM, FTIR, UV VIS, and EDXRF. Our X-ray diffraction (XRD) studies revealed a polycrystalline structure. The SEM studies exhibited porous structures advantageous for dye loading. The EDXRF shows the compositional elements. The FTIR reveals the carboxylate and photo physical properties of the dyes. The UV-VIS investigation presented band gap energies Eg of the doped as ad (BR) = 2.60 eV; bd (OO) = 1.61 eV; ccd (LL) = 1.90 eV against the as-deposited AD (g1) = 3.10 eV showing that the dyes reduced the Eg of the thin films occurring from an increased absorption coefficient α. The Nano porous, as-deposited thin films adsorb the extracted dyes on the surface and the interaction between the Nano porous films and the natural dyes used to dope BaTiO3 was studied using UV-VIS spectrophotometer with the aim of investigating their photovoltaic applicationsItem Properties of Some Distributions Using Chebyshev’s Inequality Approach(Journal of Science, Technology, Mathematics and Education, 2014-08) K. Rauf; F. A. Oguntolu; A. Isah; U. Y. AbubakarIn this article, we give a simpler proof of Chebyshev inequality and use the result to obtain some properties of Binomial, Poisson and Geometric distributions. Furthermore, analysis of the results has shown that Chebyshev inequality is effective for determining convergence bound of the distributions. Some recent sharpened results are complemented.2010 Mathematics Subject Classification, 41A50.Item Classification and Severity Estimation of Eccentricity Faults in Salient Pole Synchronous Machine using Deep Learning(IEEE, 2025) Yusuf, Latifa; Moa, Belaid; Ilamparithi, Thirumarai ChelvanThe presented research work is focused on the classification and severity estimation of eccentricity faults in Salient Pole Synchronous Machines. Building on our comparative study of Artificial Neural Network and Convolutional Neural Network for eccentricity fault classification, we propose an end-to-end deep learning model, namely Hierarchical Convolutional Neural Network, for eccentricity classification and severity estimation. The deep learning model inherently consists of an eccentricity detection component for fault classification and a severity estimation component for fault quantification. The deep learning model is built using the experimental data of a 3-phase, 2-kW, salient pole synchronous machine. The machine is subjected to 20%, 40%, and 60% severities of static and dynamic eccentricity faults under different loading conditions. Stator line currents and line-to-line voltages obtained from different operating conditions are used to train, validate and test the proposed model. To enhance the model's performance, time delay construction was incorporated to augment the datasets and carefully evaluate the impact of selected raw input features, specifically stator currents and voltages, as well as the load. Among the evaluated scenarios, the use of voltage with time delay (V, TD) as input features produced the best results, achieving 100% classification accuracy and a root mean square error of 0.0046 for static eccentricity and 0.0188 for dynamic eccentricity estimation. Results indicate that the model performs excellently in fault classification and severity estimation. Compared to traditional machine learning models, the presented model is an end-to-end deep learning architecture devoid of manual feature extraction and is robust to load variations.Item EFFECTS OF UNIFIED POWER FLOW CONTROLLER (UPFC) ON DISTANCE RELAY TRIPPING CHARACTERISTICS IN THE NORTH-CENTRAL NIGERIAN 330kV NETWORK(Nigerian Journal of Technology (NIJOTECH), 2015-10) Yusuf, LatifaThis paper investigates the effects of UPFC on Distance Relay tripping characteristics in the Nigerian 330kV (North-Central) Network. Its operation is based on impedance measurement at the relaying point. However, the system performance is often impeded by certain operational or structural factors such as load angle, the voltage magnitude ratio at the line ends, pre-fault line loading, and short circuit levels at the line ends. The Unified Power Flow controllers (UPFC) incorporated into the Nigerian 330kV (North-Central) Network were modelled in the environment of Power System Computer Aided Design (PSCAD) and kept within the protected zone of the relay to increase the Apparent Resistance, causing the relay to malfunction. Therefore, it is deduced by simulation analysis that the presence of UPFC in a faulted transmission line loop, protected by distance relay, greatly affects the trip boundaries of the distance relay by setting it to either an over-reaching or an under-reaching state. Hence, the tripping characteristics of distance relay with UPFC located at various points with respect to a fault on a transmission line culminated in three scenarios, the results of which are presented and discussed in this paper.Item Analysis of Reluctance Synchronous Motor Under Hybrid Fault Condition(IEEE, 2023-09) Ghalavand, Fatemeh; Yusuf, Latifa; Ilamparithi, Thirumarai ChelvanA small degree of static eccentricity is inevitable due to manufacturing tolerances and assembly imperfections. Therefore, when stator inter-turn fault happens, it is important to analyze it along with static eccentric condition. Unfortunately, there is not much literature that analyzes such a condition. This paper focuses on the analysis of a Reluctance Synchronous Machine (RSM) when subjected to stator inter-turn and static eccentricity faults simultaneously. In particular, the work focuses on determining the impact of relative position between the minimum airgap point and the stator inter-turn fault. The goal of the paper is achieved by simulating a 1.5 hp, 4-pole, RSM using Finite Element (FE) software. Line current data is captured under different fault conditions and motor current signature analysis is carried out. Furthermore, the lower sideband harmonic frequency is reconstructed in time domain using Inverse Fourier Fast Transform. Clarke’s transformation is applied on the reconstructed harmonic frequency currents to estimate the alpha, beta components. Afterwards, Principal Component Analysis (PCA) is implemented on the alpha, beta currents. The major benefits of the work include establishing the impact of hybrid faults on motor current signatures, developing a new measure to predict the relative position of the point of minimum airgap.Item Factors Influencing Residential Location Choices by Federal Civil Servants in Abuja, Nigeria.(2024) Bello Mustapha; Ogunbajo Rukaiyat AdeolaThe study aims to identify the key factors influencing residential location choices for federal civil servants in Abuja Nigeria. Abuja's planned development and growingItem EFFECTS OF SERVICE CHARGE ADMINISTRATION AND MANAGEMENT IN SELECTED MULTI-TENANATED COMMERCIAL BUILDINGS IN PHASE ONE, ABUJA.(2022) Fatima Mohammed; Rukaiyat Adeola OgunbajoThis paper assessed effects of service charge administration and management in selected multitenanted commercial buildings in phase one Abuja. The study was guided by these objectives which were investigating issues and challenges involved in the administration and management and assessing the occupant level of satisfaction. Data were collected by self-administered questionnaire and interview from eight (8) respondents from managers and 254 from tenant’s perspective respectively. Data was analyzed and presented using percentages, frequencies, relative satisfaction index and tables. Findings revealed that lack of transparency, lack of efficiency; improper accounting and poor facilities are the issues encountered. Howeve, the relative satisfaction index computed to show the satisfaction level of the occupants ranked Plumbing services 1st with relative satisfaction index of 0.7772, Cleaning of common services 2nd with relative satisfaction index of 0.718, refuse disposal 3rd with RSI with 0.653 while transformer maintenance has relative satisfaction index of 0 and ranked 13th. A number of guidelines should be taken in order to address the problems identified above which include Improved communication between manager and occupiers, clear disclosure of the basis for apportioning service charge costs between tenants among others.Item Development of Statistical Model For Predicting Flexible Pavement Deterioration Due To Traffic Loading(USEP: Journal of Research Information in Civil Engineering, 2024) Adamu, H. N.Flexible pavements are critical transportation components but are highly susceptible to deterioration caused by traffic loading, pavement conditions, and environmental factors. This study develops a predictive model to estimate pothole deterioration rates using traffic count and pavement structural strength. Data were collected from the Talba-Mandela road in Minna, Niger State Nigeria, over 14 weeks including weekly measurements of pothole volume, traffic counts and pavement structural numbers. A multiple linear regression model was calibrated, achieving a 𝑅² of 80.8%. Validation indicated less than 10% deviation between observed and predicted data. These findings provide a data-driven approach to optimizing pavement maintenance schedules, reducing costs, and improving road durability.Item Environmental Effects of Road Construction Waste(USEP: Journal of Research Information in Civil Engineering, 2023) S. S. Kolo; H. S. Abdulrahman; D. N. Kolo; M. Shehu; H.N AdamuThis research work investigates the various waste streams generated during road construction and their effect on environment. The method employed in this research work is categorized into waste type generated on construction site using reconnaissance surveys, data collection and data analysis methods. Four construction project sites in Minna, Nigeria, were used with the aim that these sites will provide a platform to acquire valuable data. It was discovered that mortar or concrete waste and wood waste has the highest percentage of 22% to 39% and asphalt has about 4 % waste and this was largest percentage of waste generated and this was mainly due to the human error, the use of inadequately trained and unskilled labour. The study however made case for adequate attention and concentration towards improving effective waste management by implementing proper waste management and disposal systems and encouraging the use of recycled materials in road construction. This will greatly reduce the cost of construction, increase efficiency, reduce work time and replenish the earths rapidly depleting natural resources used in construction like wood and bitumen.Item Design, Construction and Performance Evaluation of a Rice Winnowing Machine.(2013) Balami, A. A.; Fadiji, S. T.; Suleiman, A.; Simeon, Meshack Imologie; Muhammad, I. A.; Hussani, M. S; Mshelia, Z. A.