Faculty of Engineering and Technology

Permanent URI for this community

https://kwasuspace.kwasu.edu.ng/handle/123456789/8

Browse

Now showing 1 - 20 of 645

2D Flow around a Rectangular Cylinder: A Computational Study
(AFRREV STECH: An International Journal of Science and Technology, 2013-01-01) A.S., Olawore; I.F., Odesola
The unsteady flow around a rectangular cylinder is an area of great research for scientist for several years. A two-dimensional unsteady flow past a rectangular cylinder has been investigated numerically for the low Reynolds numbers (flow is laminar). Gambit has been used throughout this work to generate the geometry and meshes and the computational fluid dynamics analysis is done using fluent software. The influence of vortical structure and pressure distribution around the section of rectangular cylinders are examined and reported. The integral aerodynamic parameters are also reported. Strouhal numbers for Reynolds numbers of 55, 75, 100, 150, 250 and 400 are 0.102, 0.122, 0.129, 0.136, 0.139 and 0.158 respectively. The magnitudes of the coefficient of drag for the Reynolds numbers are 1.565, 1.524, 1.432, 1.423, 1.526 and 1.545. The lift coefficient for flow around a rectangular cylinder with a chord-to-depth ratio equal to 5 of low Reynolds numbers of 55, 75, 100, 150, 250 and 400 are 0.067, 0.101, 0.157, 0.212, 0.404 and 0.537 respectively. The pressure drags obtained in the simulations at zero angle of incidence are 1.446, 1.455, 1.439, 1.412, 1.579 and 1.602 for Reynolds numbers 55, 75, 100, 150, 225, and 250. The velocity across the rectangular cylinders varies from 0.089 to 1.02m/s. The forces caused by vortex shedding phenomenon must be taken into account when designing buildings for safe, effective and economical engineering designs.
3D Flow around a Rectangular Cylinder: a review
(AFRREV STECH, Vol. 1 (2) April-July, 2012, 2012-04-01) Odesola, Isaac F.; Olawore, Ayodeji
Turbulent flows around three-dimensional obstacles are common in nature and occur in many applications including flow around tall buildings, vehicles and computer chips. Understanding and predicting the properties of these flows are necessary for safe, effective and economical engineering designs. This paper presents the review of 3D flow around a rectangular cylinder using large eddy simulation as the turbulence model and the computational study is developed in the frame of the Benchmark on the Aerodynamics of a Rectangular Cylinder (BARC). Different simulations around bluff bodies were reviewed and the results obtained through different methodologies are presented. The effect of change by vortex shedding on the magnitude of fluid forces of rectangular cylinders are examined and reported. The aerodynamic integral parameters obtained from different papers are compared.
5G Frequencies Standardization, Technologies, Channel Models and Network Deployment: Advances, Challenges, and Future Directions
(2023) Musa, Abdulwaheed
The rapid increase in data traffic caused by the proliferation of smart devices has spurred the demand for extremely large-capacity wireless networks. Thus, faster data transmission rates and greater spectral efficiency have become critical requirements in modern-day networks. The ubiquitous 5G is an end-to-end network capable of accommodating billions of linked devices and offering high-performance broadcast services due to its several enabling technologies. However, the existing review works on 5G wireless systems examined only a subset of these enabling technologies by providing a limited coverage of the system model, performance analysis, technology advancements, and critical design issues, thus requiring further research directions. In order to fill this gap and fully grasp the potential of 5G, this study comprehensively examines various aspects of 5G technology. Specifically, a systematic and all-encompassing evaluation of the candidate 5G enabling technologies was conducted. The evolution of 5G, the progression of wireless mobile networks, potential use cases, channel models, applications, frequency standardization, key research issues, and prospects are discussed extensively. Key findings from the elaborate review reveal that these enabling technologies are critical to developing robust, flexible, dependable, and scalable 5G and future wireless communication systems. Overall, this review is useful as a resource for wireless communication researchers and specialists.
A review on application of oil palm shell as aggregate in concrete - Towards realising a pollution-free environment and sustainable concrete
(2022)
A BRIEF REVIEW OF CHARACTERISTICS AND APPLICATIONS OF SHAPE MEMORY ALLOYS IN ENGINEERING AND RELATED FIELDS
(International Journal of Mechanical Engineering and Technology (IJMET), 2021-09) Issa, W. A.; Camur, H.; Savas, M.
Shape Memory Alloys shortened as SMA’s are examples of smart materials. They sense and respond to changes in environmental conditions or stimuli, such as chemical, electrical, mechanical among others. This review, discusses the concept of SMA’s, including their engineering effects and innovations in SMA’s research. Similarly, the uses and applications of SMA’s in engineering and related fields such aerospace, biomedical, chemical, civil, electrical, and mechanical engineering are reviewed briefly including the merits and demerits of using SMA’s
A chi-square-SVM based pedagogical rule extraction method for microarray data analysis
(Institute of Advanced Engineering and Science (IAES), 2020) Salawu, Mukhtar Damola; Arowolo, Micheal Olaolu; Abdulsalam, Sulaiman Olaniyi; Isiaka, Rafiu Mope; Jimada-Ojuolape, Bilkisu; Olumide, Mudashiru Lateef; Gbolagade, Kazeem A.
Support Vector Machine (SVM) is currently an efficient classification technique due to its ability to capture nonlinearities in diagnostic systems, but it does not reveal the knowledge learnt during training. It is important to understand of how a decision is reached in the machine learning technology, such as bioinformatics. On the other hand, a decision tree has good comprehensibility; the process of converting such incomprehensible models into an understandable model is often regarded as rule extraction. In this paper we proposed an approach for extracting rules from SVM for microarray dataset by combining the merits of both the SVM and decision tree. The proposed approach consists of three steps; the SVM-CHI-SQUARE is employed to reduce the feature set. Dataset with reduced features is used to obtain SVM model and synthetic data is generated. Classification and Regression Tree (CART) is used to generate Rules as the Last phase. We use breast masses dataset from UCI repository where comprehensibility is a key requirement. From the result of the experiment as the reduced feature dataset is used, the proposed approach extracts smaller length rules, thereby improving the comprehensibility of the system. We obtained accuracy of 93.53%, sensitivity of 89.58%, specificity of 96.70%, and training time of 3.195 seconds. A comparative analysis is carried out done with other algorithms.
A Comparative Analysis of Complexity of C++ and Python Programming Languages Using Multi- Paradigm Complexity Metric (MCM)
(International Journal of Science and Research (IJSR), 2018-10-26) Balogun M. O.; Sotonwa K. A.
Software complexity metrics have used to quantifydifferent types of software properties such as cost, effort, time, maintainability, understanding and reliability. The existing metrics considered limited factors that affect software complexity, but do not consider the characteristics that affect complexity of multi-paradigm languages. In this work, a Multi-paradigm Complexity Metric (MCM) for measuring software complexity was developed for multi-paradigm codes. Multi-paradigm languages that were considered in thiswork are C++ and Python, these two languages combine the features of procedural and object oriented paradigms, therefore this research began with investigation of factors that affect the complexity of procedural code and object oriented code, so that the developed metric could be used not only for procedural code, but also either object oriented codes or in more general for multi-paradigm codes. The developed metric was then applied on sample programs written in most popular programming languages such as Python and C++, and the result of the developed metric was further evaluated with other existing complexity metrics like effective line of code (eLOC), cyclomatic complexity metric and Halstead complexity measures. The study showed that the developed complexity metric have significant comparison with the existing complexity metrics and can be used to rank numerous programs and difficulties of various modules.
A Complexity Metric for Multi-Paradigm Programming Languages
(International Journal of Emerging Technology and Advanced Engineering, 2014-04-22) Olabiyisi S. O.; Omidiora E. O.; Balogun M. O.
Software complexity metrics are used to measure variety of software properties such as cost, effort, time, maintenance, understanding and reliability. Most of the existing metrics considered limited factors that affect software complexity, but do not consider the characteristics of multi-paradigm languages. In this work, a Multi-paradigm Complexity Metric (MCM) for measuring software complexity was developed for multi-paradigm codes. Multi-paradigm languages that were used in this work combine the features of procedural and object oriented paradigms, therefore this research began with investigation of factors that affect the complexity of procedural code, thereafter with a more modern approach, the research was further extended by adding object oriented features, so that the developed metric could be used not only for procedural code, but also either object oriented codes or in more general meaning for multi-paradigm codes. The developed metric was then applied on sample programs written in most popular programming languages such as Python, Java and C++, and was further evaluated with other existing complexity metrics like effective line of code (eLOC), cyclomatic complexity metric and Halstead complexity measures. The study showed that the developed complexity metric have significant comparison with the existing complexity metrics and can be used to rank competitive programs and difficulties of various modules.
A Control Model of the Operating Head Dynamics of Jebba Hydropower System.
(Nigerian Journal of Technological Research (NJTR), 2019) Ogunbiyi O., Thomas C., Omeiza I. O. A. , Akanni J., Olufeagba B. J.
Electricity availability in Nigeria has been very poor over the years, underscoring the need for a better approach for managing generating resources. This paper presents the development of a dynamical model of the operating head of Jebba hydroelectric power plants for system studies and control system design. The mathematical model of the plant was developed from flow continuity conditions, some model parameters were obtained from the source while others were estimated from observations and analysis of the measured data. The developed dynamical equation was validated by comparing the response produced with values obtained by measurement. Upon integrating the model equation in the Microsoft EXCEL VBA® environment, a deviation of 2% from measured values was observed. Operators can therefore use the model as a decision support system, while control engineers can find the model directly applicable for optimal and robust control system design for the station.
A Direct Optimal Control of the Jebba Hydropower Station
(Institute of Electrical and Electronics Engineering (IEEE), 2019-09-01) Olalekan Ogunbiyi; Cornelius T. Thomas; Benjamin J. Olufeagba; Ibrahim S. Madugu; Busayo H. Adebiyi; Lambe M. Adesina
The optimal power generation from the Jebba hydroelectric power station is subject to the reservoir operating head, weather-related factors, units’ availability and system dynamics. In this paper, a computer control system is designed to ensure safe operation and maximize power generation. The controller is an optimal controller, which determines the amount of inflow required to regulate the reservoir operating head. The control law is an optimal control procedure developed around the steepest descent and conjugate gradient algorithm. The algorithms determine the control signal and state trajectories for minimization of a performance index defined for the regulation of the reservoir operating head. The results show that the two techniques are feasible in estimating an optimal inflow needed to move the reservoir operating head from any level to the nominal head. The two techniques were compared under different operating conditions of the hydropower system, the conjugate gradient algorithm performs better in terms of computational time. The control algorithm is recommended for use in the realization of a computer control system for the station.
A Direct Optimal Control of the Jebba Hydropower Station
(2nd International Conference of the IEEE Nigeria Computer Chapter, NigeriaComputConf, 2019) Ogunbiyi, O., Thomas, C. T., Olufeagba, B. J., Madugu, I. S., Adebiyi, B. H., & Adesina, L. M.
The optimal power generation from the Jebba hydroelectric power station is subject to the reservoir operating head, weather-related factors, units’ availability and system dynamics. In this paper, a computer control system is designed to ensure safe operation and maximize power generation. The controller is an optimal controller, which determines the amount of inflow required to regulate the reservoir operating head. The control law is an optimal control procedure developed around the steepest descent and conjugate gradient algorithm. The algorithms determine the control signal and state trajectories for the minimization of a performance index defined for the regulation of the reservoir operating head. The results show that the two techniques are feasible in estimating an optimal inflow needed to move the reservoir operating head from any level to the nominal head. The two techniques were compared under different operating conditions of the hydropower system, the conjugate gradient algorithm performs better in terms of computational time. The control algorithm is recommended for use in the realization of a computer control system for the station.
A GIS – based method for assessment and mapping of noise pollution in Ota metropolis, Nigeria
(Method Article, 2019) S.O. Oyedepo; G.A. Adeyemi; O.C. Olawole; O.I. Ohijeagbon; O.K. Fagbem; R. Solomon; S.O. Ongbali; O.P. Babalola; J.O. Dirisua; U.K. Efemwenkiekie; T. Adekeye; C.N. Nwaokocha
A Method of Colour-Histogram Matching for Nigerian Paper Currency Notes Classification
(Jordan Journal of Electrical Engineering (JJEE), 2023) Omeiza, I. O. A., Ogunbiyi, O., Ogundepo, O. Y., Otuoze, A. O., Egbune, D. O., & Osunsanya, K.
In this paper a new algorithm for the classification of three Nigerian paper currency notes, namely 200, 500, and 1000 Naira (N) denominations is presented. The work examines the effectiveness of using only colour histograms to differentiate between the classes or denominations of the three Nigerian paper currency notes. The bin-heights of the histograms of the HSI component images for the paper currencies are used as features while a rule-based classifier designed to take advantage of the changes or variations in the histogram patterns is used to classify the paper currencies into the right denomination class. The algorithm involves the utilization of a simple and effective comparison strategy as opposed to the existing, too-rigid metrics for histogram-comparison used by other authors for color indexing in content-based image retrieval systems. Over a testing data-set of 300 samples, the algorithm achieved an average classification accuracy of 98.66%, and classification accuracies of 100%, 99% and 97% for the N=200, N=500 and N=1000 denominations, respectively. The proposed algorithm does not require extensive preprocessing of the paper-currency images and as such is fast in implementation.
A Modified COST-231-Hata Path Loss Model for Typical Semi-Urban Environments in Nigeria
(KIU Journal of Science, Engineering and Technology, 2024) AKANNI, Jimoh, ISA Abdurrhaman Ademola, OGUNBIYI Olalekan, OLUFEAGBA Benjamin Jimmy
Outdoor path loss propagation modeling is critical in the planning and design of the coverage area by the Global System for Mobile Communication (GSM). For the best prediction of GSM signal at any location within its coverage region, an accurate forecast based on critical characteristics and a mathematical model is necessary. Multiple studies on path loss propagation model prediction for GSM networks conducted at various semi-urban environments in Nigeria proclaimed that propagation path loss models may provide different results when utilized in environments other than those in which they were initially designed, that car drive-test methodology was used during the data collection, and that COST-231-Hata model provides closet prediction to the practical measure values. This paper created an appropriate path loss model based on the COST-23-Hata model and outdoor measurement at 1800 MHz frequency range for the semi-urban area of Kwara State, Nigeria. The created model was used and validated with the measured data and COST-231-Hata model at other different semi-urban environments in Nigeria. The results analysis shows that the created model performed satisfactorily given the closet path loss prediction to the practical measure path loss values at all the study locations. It also gives the lowest Square Root Means Error (SRME) and Standard Deviation (SD) in all the base stations that were tested in semi-urban environments. The newly created model would therefore be more appropriate for GSM 1800 network design and installation in semi-urban environments in Kwara State, Nigeria, as well as any other semi-urban locations in Nigeria.
A Nonlinear Control Model and Operational Support System for the Kainji Hydroelectric Power System
(2019) Ogunbiyi, O., Thomas, C. T., Omeiza, I. O. A., Akanni, J., & Olufeagba, B. J.
Over the past years, the hydropower model and control were largely based on classical and linear transfer functions, this was motivated by the available control system design techniques that were available and the desire to simplify the design procedure. Such a model is inadequate for dynamic study and design of hydropower stations in the presence of uncertainties in the water head, discharge rate, elastic water effect, travelling wave effect, large variation power output and frequency. This research, therefore, focuses on developing a nonlinear model for the Kainji hydroelectric power station. The model relies on the energy conversion principles, inflows, discharge, evaporation rate and number of units on the busbar. The parameters of the model were also estimated, and the model was validated with an error within +1.4% to -3.6%. The model is expected to be used to determine the optimal control policies for the operation of the station and the release of water to downstream.
A Nonlinear Control Model and Operational Support System for the Kainji Hydroelectric Power System.
(Nigerian Journal of Technology (NIJOTECH), 2019) Ogunbiyi, O., Thomas, C. T., Omeiza, I. O. A., Akanni, J., & Olufeagba, B. J.
Over the past years, the hydropower model and control were largely based on classical and linear transfer functions, this was motivated by the available control system design techniques that were available and the desire to simplify the design procedure. Such a model is inadequate for dynamic study and design of hydropower station in the presence of uncertainties in the water head, discharge rate, elastic water effect, traveling wave effect, large variation power output and frequency. This research, therefore, focuses on developing a nonlinear model for the Kainji hydroelectric power station. The model relies on the energy conversion principles, inflows, discharge, evaporation rate and number of units on busbar. The parameters of the model were also estimated, and the model validated with an error within +1.4% to -3.6%. The model is expected to be used to determine the optimal control policies for the operation of the station and the release of water to the downstream.
A Progressive Domain Expansion Method for Solving Optimal Control Problem.
(TELKOMNIKA (Telecommunication, Computing, Electronics and Control), 2020) Ogunbiyi, O., Ogundepo, O. Y., & Sani, M. I.
Electricity generation at the hydropower stations in Nigeria has been below the expected value. While the hydro stations have a capacity to generate up to 2,380 MW, the daily average energy generated in 2017 was estimated at around 846 MW. A factor responsible for this is the lack of a proper control system to manage the transfer of resources between the cascaded Kainji-Jebba Hydropower stations operating in tandem. This paper addressed the optimal regulation of the operating head of the Jebba hydropower reservoir in the presence of system constraints, flow requirements and environmental factors that are weather-related. The resulting two-point boundary value problem was solved using the progressive expansion of domain technique as against the shooting or multiple shooting techniques. The results provide the optimal inflow required to keep the operating head of the Jebba reservoir at a nominal level, hence ensuring that the maximum number of turbo-alternator units are operated.
A Review of Exploitation Techniques of Barite Deposits of Nasarawa State, Nigeria
(2022) Abdulraman Sikiru Ottan; Itohan Otoijamun; Adedoyin Adeonipekun Dele; Azikwe Peter Onwualu
The geometry and types of barite deposit affect mining economics and processing complexity. Nasarawa state barite deposits are cavity filling types with inherent complex geometry that is beyond the comprehension of the workforce (artisanal miners) involved in the production value chain. This study reviewed the barite production from Nasarawa State; and the current exploitation techniques were evaluated through monitoring of field operations; questionnaire; and personal interview. The questionnaire addressed critical issues relating to exploitation of barite which include management and control of barite mining and processing operations; level of technical skill; mechanization; mine safety and hygiene; mine productivity; host community relation; and mineral economics related matters such as monetization of mined products. Twelve (12) barite mining locations were visited, and eighteen (18) barite veins were studied. The veins run almost parallel to each other and averagely 80cm thick, 1m wide, and overlaid by about 20m overburden of varying materials (laterite, and sandstone, etc.). Consensus submission of the respondents and interviewees is that lack of technical skill and support hinders efficient operations at the mine sites. Barite mining pits are abandoned prematurely and inexhaustibly resulting from poor exploitation techniques due to lack of adequate profiling of the deposits that impacts negatively on sustainable development of Nasarawa state barite deposits. It becomes imperative therefore to delineate the deposits and adopt appropriate exploitation technique while enhancing the technical skills of the workforce through human capacity development.
A Review of Microwave Cross Polarization in Sand and Dust Storms
(2019) Musa, Abdulwaheed
This paper presents a review of cross polarization in sand and dust storms (SDS). Relevant past works have been identified and their contributions to microwave cross polarization have been highlighted. Attention was given to semi-empirical models since they are used most readily for statistical predictions in design applications. The cross polarization mechanisms and parameters are also presented as well as a discussion about the advantages and the constraints of some of the models and their methodologies. Modified cross polarization discrimination (XPD) models for both terrestrial and slant links are proposed. Besides, the gaps in knowledge are established and the outlook of this topic in future is also suggested.
A review of solar air heater for drying of agricultural products
(Advanced Materials Research, 2014-02-27) Kareem, M.W.
Bulk of farm products need to be preserved because of their perishable nature. The cheapest and environmental friendly means is indirect usage of solar irradiance to reduce the moisture content of these products to a level that cannot sustain the activities of micro-organisms. The research on solar collector has gained its popularity over the years due to man’s quest for green energy which has led to increase in demand for the utilization of solar energy. Harnessing of solar energy by man for drying purposes was predominantly by direct method which reduces the quality and quantity of the dried products. This work presents the most recent contributions on solar air heater of flat plate absorber category. Various models, material of component parts and performance efficiency of these air heaters were discussed and there is need for collector optimization. The study was concluded with a focus on multiple pass approach of solar harvesting.

Browse

Browsing Faculty of Engineering and Technology by Title

Results Per Page

Sort Options