Department of Electrical Engineering

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    Open Access
    A Digital Twin-Enabled Smart Car Park Management System: Architecture and Impact on Emission Reduction
    (FUOYE Journal of Engineering and Technology, 2024-12-31) Ibhaze, A.E; Amusan, A.A.; Ogunleye, G.A
    Parking challenges in urban areas and educational institutions have become increasingly common due to rising vehicle numbers and rapid urbanization. The University of Lagos Engineering Car Park exemplifies these issues, experiencing inefficient space utilization, a lack of real-time monitoring, and extended search times for parking spaces. These issues mirror global parking management problems, where inadequate use of parking facilities contributes to traffic congestion and unnecessary fuel consumption. Although existing literature proposes solutions such as computer vision-based systems and sensor-based detection technologies, both approaches have their respective strengths and limitations. This work proposes a digital twin model for the smart management of the University of Lagos Engineering Car Park. The system integrates ultrasonic sensor pairs, an ESP32 microcontroller, and the Blynk IoT platform to create a real-time parking occupancy monitoring system. Ultrasonic sensor pairs are strategically positioned in each parking spot to detect vehicle presence, with data transmitted to the ESP32 microcontroller, which processes the information and sends it to the cloud via the Blynk platform. This cloud-based system provides real-time visualization of parking availability through a user-friendly interface, together with a Firebase and React-based application to display a 2D digital twin of parking spots and effectively monitor occupancy, reducing search times. The system was tested for vehicle detection accuracy, achieving 99.3% accuracy with the ultrasonic sensors. Results demonstrated a high degree of precision in detecting vehicles, with minimal delays in transmitting data from sensors to the cloud. Additionally, the system provided continuous real-time updates on parking availability through the user interface. The digital twin model would effectively reduce parking search times, improve overall campus traffic flow, minimize environmental impacts, and thus aligns with the industry 5.0 paradigm.
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    Open Access
    Ag films grown by remote plasma enhanced atomic layer deposition on different substrates
    (AIP Publishing, 2016) Amusan, A.A; Kalkofen, B; Gargouri, H; Wandel, K; Pinnow, C; Lisker, M; Burte, E
    Silver (Ag) layers were deposited by remote plasma enhanced atomic layer deposition (PALD) using Ag(fod)(PEt3) (fod¼2,2-dimethyl-6,6,7,7,8,8,8-heptafluorooctane-3,5-dionato) as precursor and hydrogen plasma on silicon substrate covered with thin films of SiO2, TiN, Ti/TiN, Co, Ni, and W at different deposition temperatures from 70 to 200 C. The deposited silver films were analyzed by x-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) with energy dispersive x-ray spectroscopy, four point probe measurement, ellipsometric measurement, x-ray fluorescence (XRF), and x-ray diffraction (XRD). XPS revealed pure Ag with carbon and oxygen contamination close to the detection limit after 30 s argon sputtering for depositions made at 120 and 200 degree C substrate temperatures. However, an oxygen contamination was detected in the Ag film deposited at 70 degree C after 12 s argon sputtering. A resistivity of 5.7x10-6 ohm cm was obtained for approximately 97 nm Ag film on SiO2/Si substrate. The thickness was determined from the SEM cross section on the SiO2/Si substrate and also compared with XRF measurements. Polycrystalline cubic Ag reflections were identified from XRD for PALD Ag films deposited at 120 and 200 degree C. Compared to W surface, where poor adhesion of the films was found, Co, Ni, TiN, Ti/TiN and SiO2 surfaces had better adhesion for silver films as revealed by SEM, TEM, and AFM images.
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    Open Access
    An Automatic Railway Level Crossing System with Crack Detection
    (IEEE, 2022) Amusan, AA; Adebakin, Y
    Railway system is a kind of transportation where passengers and goods are transported on wheeled vehicles running on rails located on tracks. This form of transportation is usually inexpensive, secure, and often the most convenient. In areas with frequent use of railway transport system, there is need to limit the accidents at the level crossing, mitigate the falling of trains on the rail due to cracks and create an excellent feedback system. The manual management of the system is inconvenient, time wasting and prone to sudden accidents. Hence in this work, an automatic railway system which includes automatic level crossing and crack detection system with an excellent feedback process is developed using ultrasonic sensors and microcontrollers for control. The system is unique because it uses ultrasonic sensors for maximum performance. The developed system detects cracks on the rail, automatically controls the level crossing to avoid collision and send all possible feedbacks to a remote station using the SIM module. The reliability assessment of the system gave 93.3%. The system is reliable, efficient, and convenient and it is recommended for areas where rail transport systems are demanding.
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    Open Access
    ANALYSIS OF THE TRANSIENT STABILITY LIMIT OF NIGERIA’S 330kV TRANSMISSION SUB-NETWORK
    (Faculty of Engineering, University of Nigeria, Nsukka, 2017-01) Oluseyi, P.O.; Adelaja, T.S.; Akinbulire, T.O.
    The poor investment in the network expansion programme has led to high level of grid fragility experienced in the power transmission system in Nigeria. Thus, any little disturbance often results in cascaded outage which is very hazardous to the power system equipment and operation. In order to overcome or ameliorate the influence of this challenge, the network engineers have to devise methodologies based on the dynamic stability analysis. This motivates the development of power system transient stability model presented herein. The developed model is thus applied to a specimen of the Nigeria’s transmission power system, i.e. the Ikeja-West Sub-network. This choice is influenced by the fact that the Ikeja-West sub-network is the hub of power transmission arteries in Nigeria. Thus the Electrical Transient and Analysis Program (ETAP) software is deployed to operate on the ensuing model. This then leads to generating a series of results that demonstrates the different scenarios in respect of the system stability studies. The method adopted is quite appealing and promising as a tool in sustaining system stability and security during slight disturbance to the network during operation.
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    Open Access
    Application of atomic layer deposited dopant sources for ultra‐shallow doping of silicon
    (Wiley-VCH, 2014) Kalkofen, B; Lisker, M; Burte, E; Amusan, A.A
    The advanced silicon semiconductor technology requires doping methods for production of ultra-shallow junctions with sufficiently low sheet resistance. Furthermore, advanced 3-dimensional topologies may require controlled local doping that cannot be achieved by ionimplantation. Here, the application of the atomic layer deposition (ALD) method for pre-deposition of dopant sources is presented. Antimony oxide and boron oxide were investigated for such application. Ozone-based ALD was carried out on silicon wafers by using triethylantimony or tris-(dimethylamido)borane. Very homogeneous Sb2O5 deposition could be achieved on flat silicon wafers and in trench structures. The thermal stability of antimony oxide layers was investigated by rapid thermal annealing experiments. The layers were not stable above 750 ◦C. Therefore, this material failed to act as dopant source so far. In contrast, ultra-shallow boron doping of silicon from ALD grown boron oxide films was successful. However, pure B2O3 films were highly unstable after exposure to ambient air. The boron oxide films could be protected by thin Sb2O5 or Al2O3 films that were in-situ grown by ALD. Low temperature ALD of Al2O3 at 50 ◦C from trimethylaluminium (TMA) and ozone was investigated in detail with respect of its protective effect on boron oxide. Interestingly, it was observed that already one ALD cycle of TMA and O3 resulted in significant increase in stability of the boron oxide in air.
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    Open Access
    Assessment of electrical grid fragility in Nigeria-31 bus system
    (Faculty of Engineering, University of Maiduguri, Maiduguri, Nigeria., 2018-12) Oluseyi, P.O.; Ajekigbe, T.O.; Babatunde, O.M.; Akinbulire, T.O.
    The grid fragility is a prevalent challenge in Nigeria electricity supply industry (NESI). It has resulted in recorded incidents of voltage collapse which have been on the increase in the recent time. Meanwhile to evaluate this events; thus the nexus between voltage collapse and network capacity was explored. To actualize this, the load flow analysis was carried out on the Nigeria-31 bus system with the aid of the Newton-Raphson iteration technique. Using the relevant parameters (such as bus voltage magnitude, bus voltage angle, generated power, injected power as well as load magnitude) obtained from the analysis, the line stability index and line stability factor were obtained for every line in the network. It was discovered from the values of line stability index that Lines (26-2); (31-7); (10-11); (24-10) and (18-12) are weak and fragile while for the line stability factor, the values obtained for Lines (10-8); (11-8); (11-10); (24-10) and (18-12) indicate the fragility of some of the lines in the Nigerian Transmission Network. From this, it was established that the weakest lines were those whose values range from 0.3051 to 0.8813 for the line stability index. Correspondingly; any line that takes the value between 0.2737 and 0.9924 in respect of the line stability factor was also marked as the weakest lines in the network. Thus it was noticed that for the two line stability indices (i.e. stability factor and stability index); Line (11-10) i.e. from Oshogbo to Ikeja- West bus is the most fragile line in Nigeria-31 bus transmission network while the nearest to it are lines (24-10) i.e. from Ayede to Ikeja-West bus and (12-18) i.e. from Kaduna to Kano bus. This study is potentially sufficient for determining the lines in the transmission network that require utmost consideration for reinforcement in respect of the transmission expansion planning schemes.
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    Open Access
    Assessment of energy consumption and carbon footprint from the hotel sector within Lagos, Nigeria
    (Elsevier/Science Direct, 2016-02) Oluseyi, Peter Olabisi; Babatunde, O. Moses; Babatunde, Oluwabori A.
    Nigeria has one of the lowest electricity consumption per capita in Africa and this is because the power grid capacity has not been able to meet the ever increasing demand for electricity. To remain in business, several business enterprises rely on captive generation of electricity; thus, the hospitality industry is not left out of this experience. Primarily, this study evaluates the energy consumption trend in the Nigerian hotel industry. The energy utilization is modeled in order to appraise its influence on the emission level of the diesel generators, which is the major source of electricity supply in Nigeria. The linear regression method is employed for the characterization of the energy utilization index. Also, correlation analysis is employed to investigate the interdependence of carbon footprint and normalized energy consumption. Results show a significant correlation between energy consumption per unit guest room and the carbon dioxide emission level. This work develops a carbon footprint protocol for the hotel industry in Nigeria by recommending that the annual energy consumption per unit guestroom should be kept at a value not more than 40.278 MWh/guestroom while the annual energy consumption per unit equivalent guest room should be less than 62.861 MWh/equivalent guestroom.
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    Open Access
    Assessment of the Scope and Usage of Digital Dividend in Nigeria
    (ATBU Journal of Science, Technology and Education (JOSTE), 2020) Gbenga-Ilori, A.O.; Sanusi, O.I.
    The rapid pace of innovation in wireless technology has placed increasing demand on the frequency spectrum in the last decade. The evolution of digital television provided a way of meeting this spectrum demand since a substantial part of the television spectrum could be released for other services after digital switchover. In this paper, we estimate the spectrum savings possible from digital television switchover in Nigeria. The paper shows that it is possible to save 168MHz as digital dividend after the transition to digital television. The paper also considers the country’s decision to use this dividend for digital television and mobile broadband by determining if this is the optimal choice for Nigeria based on technical, economic and social constraints. Findings show that, technically, the services can coexist if proper measures are taken during the planning stage of the national digital television network. Findings also show that both services have huge economic and social value to the nation. The paper recommends that social value take a higher priority over economic value in a developing country like Nigeria to bridge the existing digital divide. Finally, recommendations on a feasible digital television migration framework for Nigeria were made to the government and stakeholders.
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    Open Access
    Comparative Load Flow Analysis of UNILAG Power Distribution Network using Newton Raphson and Gauss Seidel Methods
    (Faculty of Engineering, University of Benin, Benin City, Nigeria, 2019-06) Akinbulire, T.O.; Oluseyi, P.O.; Udoakam, G.A.; Babatunde, O.M.
    The evaluation of power flow in the distribution network has many techniques but there has been a very much interest in the traditionally known methods. These methods have enjoyed very wide acceptability and applicability. However, a comparative study of these techniques for the investigation of the load flow analysis for any of the Nigeria’s distribution systems is not adequately and proficiently documented. Thus, this inspired the adaptation of these techniques for the solution of a structured distribution network in the University of Lagos (UNILAG) Campus. The opportunity presented by this research is the deployment of these methods for the analysis and testing of a reallife power distribution network. The results obtained were validated with the IEEE-9 bus and IEEE-30 bus systems. The results obtained for the Campus distribution network were not only highly revealing but it also provided comparatively information (in respect of GS versus NR) as follows: number of iterations (i.e. 3 versus 177) , convergence time (i.e. 0.2457 versus 0.3276), power mismatch (0.017 MVAr versus 0.00 MVAr), system losses (i.e. 0.854 MW versus 0.855 MW), iteration tolerance (0.00001 versus 0.00) From this, the compared results indicated that the NR method converges faster with a least number of iterations irrespective of the number of the system buses while in the GS method, the number of iterations increases proportionally as the number of buses increases. Thus, it is evidently established that the NR method is very adequate for the analysis of large distribution networks.
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    Open Access
    COMPARATIVE STUDY OF META-HEURISTIC AND CLASSICAL TECHNIQUES FOR AUTOMATIC GENERATION CONTROL OF A MULTI-SOURCE SINGLEAREA HYDRO-THERMAL-GAS POWER SYSTEM
    (2019-07-26) Dinakin, D.D.; Oluseyi, P.O.
    The PID controller still remains a widely used and very effective means of achieving stability in control systems. Generally, the performance of the controller is determined by the proportional, integral and derivative gains of the controller. The classical techniques: ZieglerNichols (ZN) open loop method; ZN closed loop method; Chien-Hrones-Reswick (C-H-R) load rejection method; and meta-heuristic technique: the fuzzy logic algorithm, are used to determine the tuning parameters of the PID controller in this study. The performance comparison of these controllers is done for automatic generation control (AGC) of a multi-source single-area hydrothermal-gas power system. In such power systems, each source has a participation factor that determines its contribution to total power generation. The root mean square error (RMSE) is deployed to determine the proportionate balance of each generator’s output with its corresponding participation factor. The performance comparison of the controllers using Simulink/MATLAB shows that the fuzzy-PID controller achieved the most proportionate generation balance.
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    Open Access
    Computer-Aided Instruction in Electrical Engineering Education
    (2002-09-23) Okafor, F.N; Akinbulire, T.O; Awosope, C.O
    This paper discusses the experiences of the authors in the application of computer aided instruction (CAI) to Electrical Engineering Education. Examples of some CAI tools developed by the authors are presented. Also discussed are problem associated with development and/or acquisition of the necessary tools for CAI in a developing country like Nigeria.
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    Open Access
    Concerning the Circular- and Square-loop Antennas Mounted over a Ground Plane of Finite Extent
    (2015-07) Ayorinde, A. A.; Adekola, S. A.; Mowete, A. I.
    As a natural sequel to an earlier presentation [1], which compared the performance features of equal perimeter circular- and square-loop antennas located over finite ground planes, this paper, using the same formulation, examines the same performance characteristics, but this time, with the antennas being of equal cross-sectional areas; and with loop heights varying between 0.05,). and l.00')' at the operating (center) frequency of l.25 GHz. Computational results for the antennas' input characteristics reveal that whereas they share virtually identical input resistance profiles, input reactance for the square loop has values that are in general, lower than those for the circular loop, for the entire range of 'height above ground plane' considered. Results for the E- and H-plane radiation field patterns indicate that when the loops are located at heights beyond 0.3,), above the finite ground plane, the front-lobes become distorted; an observation supported by the profiles of the forward directive gain, which display the 'notch filter response' behavior. Furthermore, the results suggest that acceptable front-to-back ratio performance can only be maintained if loop heights above the ground plane are kept below 0.3,),.
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    Open Access
    Design and simulation of 1.28 Tbps dense wavelength division multiplex system suitable for long haul backbone
    (De Gruyter, 2018) Amusan, A.A; Amusan, E
    Wavelength division multiplex (WDM) system with on/off keying (OOK) modulation and direct detection (DD) is generally simple to implement, less expensive and energy efficient. The determination of the possible design capacity limit, in terms of the bit rate – distance product in WDM – OOK –DD systems is therefore crucial, considering transmitter/receiver simplicity, as well as energy and cost efficiency. A 32-channel WDM system is designed and simulated over 1000 km fiber length using Optsim commercial simulation software. The standard channel spacing of 0.4 nm was used in the C–band range from 1.5436 to 1.556 nm. Each channel used the simple non return to zero – on/off keying (NRZ – OOK) modulation format to modulate a continuous wave (CW) laser source at 40 Gbps using an external modulator, while the receiver uses a DD scheme. It is proposed that the design will be suitable for long haul mobile backbone in a national network, since up to 1.28 Tbps data rates can be transmitted over 1000 km. A bit rate length product of 1.28 Pbps.km was obtained as the optimum capacity limit in 32 channel dispersion managed WDM – OOK – DD system.
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    Open Access
    Development of a model for mitigating fire spread in multi-storey buildings
    (Faculty of Engineering University of Maiduguri, Maiduguri- Nigeria, 2019-06) Oluseyi, P.O.; Akinbulire, T.O.; Atunbi, C.T.; Akinyemi, M.I.
    In the developing nations that are located in the tropical region; there is a growing trend of fire incidence in buildings without adequate development of fire prevention and/or reduction protocol. Thus, this study addresses the growth and spread of fire in multi-storey buildings. The rooms are structured as cells in order to reduce the flame spread from a single fuel item, by heat release, to other neighbouring items or rooms (otherwise known as cells). The philosophy is to reduce the advent of vertical and horizontal fire spread. Thus, the mathematical model for the spread of fire in buildings over a solid fuel surface is therefore developed using the adaptation, development and simulation of cellular automata (CA) discrete model. The von Neumann neighbourhood cell configuration is adopted. Hence, the surface of the fuel is analysed using a regular square array (i.e. cells), while the flame spread is depicted as a series of ignitions of surface elements. In which case, ignition of an element is evaluated by a combination of critical surface ignition temperature and cellular automata discrete techniques. The work displays the movement of fire, from its origin of ignition to other fuel igniting elements around it. Consequently, this spread to other parts of the building. However, the technique presented in this work attempts to reduce the rate of growth of the fire spread using the predictive fire growth probability approach. In other words, the application of the cellular automata, using a multi-storey building, is herein presented. The study has potential to advance knowledge of technical approach to stop fire spread in multi-storey building. Thus it improves fire risk management as well as reducing magnitude of fire disaster and losses in the multi-storey buildings.
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    Open Access
    Development of a Smart Plastic Collection System with IoT Remote Cloud Payment Platform
    (LAUTECH Journal of Engineering and Technology, 2025-07-11) Amusan, A.A; Afolabi, A; Sambo, M
    Plastic bottle littering has undoubtedly become an alarming global crisis and a major source of concern that poses potential hazards to landfills, habitats, water bodies, and the ozone layer. A number of these plastic bottles significantly find their way into the drainage systems leading to total drainage blockage resulting in flooding which has rendered many lives dead and homeless. Given the severity of plastic bottle pollution, immediate action is required to lessen its negative consequences. Consequently, while the existing work deployed calibrated sensors that impaired sensing accuracy, and also no consideration for incentives to encourage depositors. This project employs Autodesk Inventor software for robust mechanical modeling, incorporates sensor-based components for precise sensing, implements a control mechanism, and utilizes IoT remote cloud for payment systems to foster local involvement and social accountability aimed at eradicating plastic bottle littering. This initiative outlines the development of a smart plastic collection system with a view to not only curtailing plastic bottle littering but also motivating people with a reward. The smart plastic collection system accepts plastic bottles and all other objects such as glass, metal, and cans.
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    Open Access
    Development of a Solar-Powered Automatic Car Park Management System
    (Editura Universitatii din Pitesti, 2024) Amusan, A.A; Agan, D; Ogidan, O; Longe, O.
    Parking of cars can be considered a serious issue in developed and developing nations. Many cities suffer from a lack of automobile parking space because of the rapid increase in number of car owners. Urban parking issues often stem from an imbalance where the number of cars seeking parking exceeds the available parking spaces, creating a persistent congestion and difficulty in finding suitable parking spots. The manual system of managing car parking space can be cumbersome and always prone to chaos. Most efforts found in literature to automate car parking systems concentrate on software solutions, either using image processing to find vacant spaces or using mathematical methods to find and reserve a parking space. The aim of this work is to design and implement a solar-powered car park automation system using sensors (light dependent resistor sensors and infrared sensors) and controllers (Arduino). The system is designed to improve the efficiency and convenience of car park operations, while also reducing energy consumption and the carbon footprint of the car park. To achieve this, the sensors and controllers that automated the car park’s operations were powered by solar panels installed in the car park. Sensors were used to detect the presence of vehicles in the car park and to determine the availability of parking spaces, while controllers were programmed to open and close gates, control lighting and ventilation. The solar-powered car park automation system was tested and evaluated under different conditions and at different times of the day to show that the system was able to reduce energy consumption and improve the utilization of parking spaces in a closed area. The system was found to be 99.5% reliable with no false positive but single false negative attributed to accidental error. The system is easy to use and assist towards achieving sustainable development goals 7, 9, 11 and 13.
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    Open Access
    Development of energy benchmarking protocol for commercial banks, Lagos state, Nigeria
    (Routledge Taylor & Francis, 201-09-26) Akinbulire, T.O.; Oluseyi, P.O.; Babatunde, O.M.; Ayegbajeje, A.E.
    Energy consumption is a central factor taken into consideration as far as management decisions are concerned in any firm and the same goes for the banking industry. More importantly is the extent to which firms consume energy efficiently. In the light of this, this study investigates the energy benchmarking of 50 commercial bank branches in Lagos. With the aid of questionnaires and by observation and consultation with the staff of the selected bank branches, data were collected on the energy use as well as several other variables that influence energy use intensity. An energy use intensity model was estimated using the fixed, random and pooled ordinary least square specifications and the predicted energy use intensity was constructed. Armed with the observed and predicted energy use intensities, an absolute benchmarking was conducted while a relative benchmarking was also conducted with the aid of the Data Envelopment Analysis (DEA) technique. The results of the regression analysis revealed a maximum of 60% of the branches of banks are energy efficient. However, the results of the DEA suggest that only a single branch of the 50 sampled branches was energy efficient while the other banks fell below the energy efficiency frontier with some banks performing relatively poorer than the others.
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    Open Access
    Development of optimal placement of distributed generators in electrical network using improved strength pareto evolutionary algorithm
    (Faculty of Engineering, Ahmadu Bello University, Samaru-Zaria, Nigeria, 2019-08) Oluseyi, P.O.; Iro, I.U.; Ighravwe, D.; Babatunde, O.M.
    In recent times, the issue of the gap between electricity supply and demand has been addressed using distributed generation (DG) technology. When DG technology is properly placed within a transmission and distribution network, there is always improvement in power loss reduction, voltage profile and system reliability. Proper placement can be achieved by evaluating the optimal values for voltage deviation, real power loss and bus voltage. Thus, this study presents a multi-objective DG optimisation model that minimizes of voltage deviation and real power loss, while maximising voltage stability factor. Themodel was formulated as a multi-objective problem and solved using an improved Strength Pareto Evolutionary Algorithm (SPEA-2) technique of optimisation to DG problem. The Nigeria-31 bus, 330 KV, transmission network was considered as test case. The results obtained were validated with the standard IEEE 30-bus system. In addition, this study presented scenarios where 1, 2 and 3 DGs were placed into these test cases. Based on the SPEA-2 implementation, the optimisation run time for the Nigerian network and the IEEE network were 2229.55 and 2039.42 secs, respectively. The optimal bus location of the three DGs (whose capacities are: 8.7793 MW/6.1272 MVAr, 8.1806 MW/4.7778 MVAr and 7.9567 MW/4.6281 MVAr respectively) for the IEEE 30 bus were 5,7 and 26 buses, respectively, while for the Nigerian-31 bus were 14, 15 and 17 (whose capacities are: 22.9693 MW/15.2956 MVAr, 27.3711 MW/21.7274 MVAr and 30.9910 MW/15.4069 MVAr respectively) respectively. For the placement of these DGs, the power loss reduction in the IEEE-30 bus is 16.17 MW, 15.28 MW, 14.07 MW respectively and 64.21 MVAr, 61.19 MVAr, 56.13 MVAr respectively. While for the Nigeria-31 bus system; the reduction in power loss is: 34.66MW, 33.99 MW, 33.82 MW and 411.85 MVAr, 403.45 MVAr, 400.54 MVAr respectively. The results obtained showed that the total power losses reduced as DGs are sited at the optimal locations for the two test cases when compared with cases when DGs were not considered.
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    Open Access
    Directing the digital dividend towards bridging the digital divide in Nigeria
    (European Journal of Scientific Research, 2010) Gbenga-Ilori, A.O.; Ibiyemi, T.S.
    In this work we investigate the use of digital dividend from the transition of analogue to digital terrestrial television broadcasting to bridge the digital divide between urban and rural areas of Nigeria. First, we predict that 77% of the VHF and UHF spectrum can be freed up and released for other communication services after transition to digital television. We also presented a few of the services competing for the use of the freed spectrum and considered necessary approaches in estimating the values and benefit of allocating this digital dividend to each of these services. These approaches were based on technical considerations, economic and social benefits. Results show that wireless broadband for fixed reception had the highest recommendation for the use of the digital dividend because of its potential capacity of bridging the digital divide in rural areas of the country and its relatively high revenue potentials. Finally, challenges that could hinder the successful transition to digital terrestrial television and the release of the digital dividend in Nigeria were identified and necessary recommendations were made to government and policy makers on ways to address these problems.
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    Open Access
    Effect of Atmospheric Impairments on Ku-band Free-to-Air Digital Satellite Television Signals in Lagos State
    (Nigerian Journal of Technology (NIJOTECH), 2020) Gbenga-Ilori, A.O.
    With the rapid deployment of free-to-air satellite television, there is an increasing need for an accurate propagation prediction tool for satellite link planning. This paper presents an evaluation of deterministic propagation model that is best for the analysis of satellite signal quality at Ku-band in Lagos state, Nigeria. The paper aims at comparing accurate measurements of channel-to-noise (C/N0) and bit error rate (BER) taken at six locations within Lagos state with simulation results derived from the Institut für Rundfunktechnik (IRT) model and modified irregular terrain model (ITM) deterministic propagation models. The work considered the effect of the type of modulation scheme and error correction code used on the C/N0 and BER received using these deterministic propagation models. Results show a deviation of 0.732 dB and 0.285 dB from C/No measurements using the IRT and modified ITM models respectively. This work shows that at more than 1% of the time, both models performed well when compared with measurements. However, at less than 1% of the time, which accounts for periods of heavy rainfall, the modified ITM model performed better. The paper also shows that when error correction code is not used with the modulation scheme deployed, the BER increases rapidly and the effect of using a higher alternate modulation symbol is not evident on achievable data rates.