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Optimization of multiple performance responses of a fish feed pelletizer machine
Get PDFThis study details the assembling of a prefabricated fish feed pelletizing machine and optimization of some operational parameters such as die thickness, number of die holes, shaft speed and feed rate to produce high-grade fish pellets. The Taguchi methodology and Grey relational analysis (GRA) have been utilized to evaluate the multi-objective functions of interest such as pelletizing efficiency, throughput, energy requirements and pellets bulk density (g/cm3). The pelletizer machine performance evaluation test was carried at 3 levels of die thickness (8, 6 and 12 mm), number of die holes (30, 25, and 35), and feed rates (145, 130 and 160 g/h). The test for the performance indicators was conducted using L9 orthogonal array experimental design. The test data were analyzed using the Taguchi scheme employing the signal-to-noise ratio response with effects deduced. The GRA was utilized to assess multiple responses by fusing the Taguchi technique with the GRA. Thus the multi-objective optimization was transformed to a single equivalent objective function. The results of Taguchi optimization revealed that die thickness was the most influential parameter for the various control factors. In addition, optimum parameter combination was obtainable at medium die thickness (8mm), medium number of die holes (30), low shaft speed (200rpm) and medium feed rate of 145g/h. Analysis of variance for grey relational grade (GRG) reveals that die thickness and feed rate are the dominant parameters. The confirmation test performed shows that the GRG is enhanced by 2.19%
Advances in natural rubber seed shell utilization in polymer technology
Get PDFThe valorization of rubber seed shell into useful materials for industrial applications in polymer technology is of great interest. The usefulness of this material is borne out of the ease of processing; it’s readily available at low or no cost, and less abrasive to equipment. Literature and research reports have shown that rubber seed shell has gained applications in the adhesive industry as reinforcing additive, in electrode manufacturing, as filler in polymer composites, as sorbent in the uptake of heavy metals during waste water treatments, as starting material in the production carbon materials for value added products for the industry. However, there are still outstanding prospects in the utilization of this material in various areas of polymer technology such as a lignocellulosic source for the production of biodegradable foams, polymer gels, second generation bio-plastics and biofuels, and as surfactants. This review examines the results of a retrospective and prospective study in polymer technology of the latent properties inherent in rubber seed shell with particular emphasis on its utilization in polymer technology
Application of nonlinear autoregressive neural network to estimation of global solar radiation over Nigeria
Get PDFIn this paper, surface data meteorological were used as input variables to create, train and validate the network in which global solar radiation serves as a target. These surface data were obtained from the archives of the European centre for Medium-Range weather forecast for a span of 36 years (1980-2015) over Nigeria. The research aims to evaluate the predictive ability of the nonlinear autoregressive neural network with exogenous input (NARX) model compared with the multivariate linear regression (MLR) model using the statistical metrics. Model selection analysis using the index of agreement (dr) metric showed that the MLR and NARX models have values of 0.710 and 0.853 in the Sahel, 0.748 and 0.849 in the Guinea Savannah, 0.664 and 0.791 in the Derived Savannah, 0.634 and 0.824 in the Coastal regions, and 0.771 and 0.806 in entire Nigeria respectively. Meanwhile, error analyses of the models using root mean square errors (RMSE) showed the values of 1.720 W/m2 and 1.417 in the Sahel region, 2.329 W/m2 and 1.985 W/m2 in the Guinea Savannah region, 2.459 W/m2 and 2.272 W/m2 in the Derived Savannah region, 2.397 W/m2 and 2.261 W/m2 in the Coastal region and 1.691 W/m2 and 1.600 W/m2 in entire Nigeria for MLR and NARX models respectively. These showed that the NARX model has higher dr values and lower RMSE values over all the climatic regions and entire Nigeria than the MLR model. Finally, it can be inferred from these metrics that the NARX model gives a better prediction of global solar radiation than the traditional common MLR models in all the zones in Nigeria
Experimental study on silver nanoparticles: synthesis, photo-degradation and analysis
Get PDFThe aim of present study was waste water treatment via advanced oxidation process (AOP). Wet chemical precipitation method was used to prepare silver nanoparticles (Ag NPs). The Ag NPs were employed for photo catalytic degradation of Congo red (CR) dye in aqueous medium. The scanning electron microscopy (SEM) investigation shows agglomerated form of Ag NPs. The average sizes of agglomerations are below 600 nm. Energy dispersive X-rays spectroscopy (EDX) and ultraviolet light visible spectroscopy (UV/Vis) also established the formation of Ag NPs. The photo-degradation study reveals that Ag NPs degraded by 73% of CR dye in 480 min. Catalytic dosage study shows the dye degradation was increased vice versa as increased the amount of Ag NPs and then almost level off after 0.025 g of catalyst. In pH study it was observed that degradation of CR dye increased as pH increased. The recovered catalyst study also significantly degraded the CR dye
A fuzzy logic model for evaluating the standard performance of a prototype online voting system
Get PDFThis paper described the major challenges associated with existing methods of voting; hence a prototype online voting system was developed and proposed for credible election in Edo state with a mind set to trash out the various problems identified with the existing system. In order to determine if the prototype online voting system developed is of standard performance a fuzzy clustering means (FCM) was designed to evaluate and ascertain its performance based on certain criteria gathered using questionnaire designed. The FCM model was simulated and tested for evaluation taking into consideration stakeholders of election that were drawn from twelve (12) local government areas, out of the Eighteen (18) local government areas of Edo state. Opinions of stakeholders of the election concerning the wished-for model were arbitrarily sampled and analyzed for the use of assessment in particular when compared to the present system of selection. In addition, other factors that can promise an open and just election were also discussed and place into consideration throughout the implementation of the developed prototype online voting system. The result from the evaluation revealed that the seven (7) local government areas which formed about (58.33%) of the beyond least standard cluster and the five (5) local government areas, which also formed about (41.66%) of the regular standard cluster of the entire population of (12) local government areas were both above the average acceptable benchmark for elections, which is a key indicator that the developed prototype online voting software meets more than the standard for a credible election process and it is therefore proficient as a verdict announcer for a transparent electoral process when fully implemented and deployed for usage
The design and practical implementation of a six-phase induction motor
Get PDFThis thesis presents a re-designed conventional three phase 5-hp squirrel cage, 4-pole, 48 slots induction motor to a six-phase induction motor (SPIM). It also presents the in-depth of a single layer winding of a three-phase motor that was re-design to the six-phase split winding layout which was practically explained to the understanding of both the engineers and the technicians who normally find it difficult with windings of electrical machines. The optimized re-designed SPIM is presented in the MATLAB/Simulink environment to perform a comparative assessment of the different phase loss scenarios of the six-phase configuration with respect to the six-phase healthy case and its conventional three-phase induction motor. The result shows a comparative benefit of the six-phase induction motor over the three-phase induction motor; in such that in the near future because of its effective way to provide a higher reliability and sustainability under the loss of phase/phases condition it will be practically applied in the power driven devices/machines like in the area of Electric Vehicles, etc
Performance evaluation of 2.4kVA grid-tie inverter
Get PDFThis paper is focused on experimenting the overall performance of a 2.4kVA direct solar power supply system. The overall aim is to implement a solar power supply system without a battery back-up in order to minimize cost. The objectives include measuring the performance of grid-tie inverter, determine its period of operation under load conditions, to make the use of batteries optional in solar power supply system and minimize initial cost of installation. Various tests (variable load, fixed load and no-load) were carried out for the purpose of analysis. A dual trace digital storage oscilloscope was used to monitor the output waveform of the inverter to observe possible harmonic distortion on the waveform. The inverter takes its input power directly from the solar modules (panels) through the maximum power point tracker (MPPT) charge controller. Each category of test was conducted for at least three days of different weather conditions, to determine how variation in the sun’s intensity (irradiance) affects the operation of the inverter and its output power. Test results show that the inverter performs its function during the day apart from the early hours in the morning and later in the evening of each day, and the loads were powered successfully during the period of test. The output waveform as observed from the oscilloscope is not purely sinusoidal; it is rather a modified sine wave
Impact of faults on bus stability on an island 330kV mesh network on the Nigerian grid
Get PDFThis study carried out an assessment on the impact of faults on bus stability along the Benin-IkejaWest-Aiyede-Oshogbo-Benin (BIAOB) 330kV island network. The sensitivity of BIAOB as a ring network on the Nigerian grid aroused the interest behind its choice for this study. The network parameters were collated from the National Control Centre, Oshogbo and the network was modeled on the MATLAB 2015 environment using the obtained data. A high reactive power flow was observed in all the buses while the lowest voltage profile was observed on the Line-Line-Line-Ground (L-L-L-G) simulated in bus 1. This is an indication that symmetrical faults have the greatest impact on the network. Further results showed that the BIAOB network has a better voltage profile when compared with other radial network from existing literature. The paper concluded by recommending the closure of more radial network on the grid in order to improve its performance
Effect of under belting a multiple V-belt drive
Get PDFThe paper seeks to explore the effect of under belting a multiple V-belt drive on the life of a given sets of belts. Under belting a device means using fewer belts than recommended by good design practices. The experiment investigates the incremental reduction of the number of belts by one and the attendant effect on the life of the whole belts set. The experiment is based on ten belts being the normal required to drive the load. The experiment emphasizes the effect of reducing one V belt on the life of the whole set. The experiment was based on 100% efficiency on the whole life of the whole sets from 10 belts, which is the required to drive the load. Effect of belt creep was neglected. It was progressively decreased by one and the whole belt life was evaluated based on the reductio
A survey on artificial intelligence based techniques for diagnosis of hepatitis variants
Get PDFHepatitis is a dreaded disease that has taken the lives of so many people over the recent past years. The research survey shows that hepatitis viral disease has five major variants referred to as Hepatitis A, B, C, D, and E. Scholars over the years have tried to find an alternative diagnostic means for hepatitis disease using artificial intelligence (AI) techniques in order to save lives. This study extensively reviewed 37 papers on AI based techniques for diagnosing core hepatitis viral disease. Results showed that Hepatitis B (30%) and C (3%) were the only types of hepatitis the AI-based techniques were used to diagnose and properly classified out of the five major types, while (67%) of the paper reviewed diagnosed hepatitis disease based on the different AI based approach but were not classified into any of the five major types. Results from the study also revealed that 18 out of the 37 papers reviewed used hybrid approach, while the remaining 19 used single AI based approach. This shows no significance in terms of technique usage in modeling intelligence into application. This study reveals furthermore a serious gap in knowledge in terms of single hepatitis type prediction or diagnosis in all the papers considered, and recommends that the future road map should be in the aspect of integrating the major hepatitis variants into a single predictive model using effective intelligent machine learning techniques in order to reduce cost of diagnosis and quick treatment of patients