Browsing by Author "J. Y. Jiya"

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A Fundamental Review of Trends in Perovskite Solar Cells Based on Introduction of Buffer Layers to Enhance Stability
(JOURNAL OF SCIENCE TECHNOLOGY AND EDUCATION, 2020) J. Y. Jiya; J. S. Enaburekhan; M. T. Jimoh; E. C. Egwim
Perovskite solar cells (PSCs), as photo-electric conversion devices, exhibit adequate power conversion efficiency (PCE) and low processing cost and have thus become one of the most promising devices to replace conventional silicon-based solar cells thereby addressing current prevailing energy issues. Despite rapid progress in the perovskite solar cell efficiency, there have been concerns about issues which could affect the measurement accuracy and/or practical applications of these devices, amongst which are stability, scaling up (large area devices), and possible environmental effects related to the use of lead-based active material. Current PSCs use nonbiodegradable petroleum-based polymer substrates, discarding of which will aggravate environmental pollution. In this study, a review of the fundamentals and progress in the perovskite solar cell (PSC) is discussed. The processing cost of metal electrode deposition in PSC is very costly, hence, the replacement of the metal electrode by some other low-cost counter electrode is discussed.
Application of Inverse method to Reconstruct the form of Pulse During Impulsive damage to Pipelines
(International Engineering Conference (IEC), 2015) O. A. Olugboji; J. Hale; J. Y. Jiya; C. K. Jack
Petroleum pipelines damages if untimely detected, poses a tremendous challenge to the oil sector of an economy as it causes oil spillage, theft or explosion of the petroleum products while on transit. It is against this backlash an inverse pulse propagation method for reconstructing the form of pulse generated during pipeline defects was devised and presented in this paper. Inverse problem occurs in several branches of science and engineering. It involves the determination of the parameters of a model that describes or explains a set of observed data .This work deals with an inversion technique that was developed to reconstruct the form of a pulse after it has been propagated along a pipe. To test the suitability of the developed technique, a mathematical model was developed. The theoretical model was validated by experiment using a developed pipeline system. The experimental test rig comprises of a flexible hose pipe 23m long and 19mm diameter with four pressure sensors distributed along the pipeline and connected to the data acquisition system. Static and flowing air in the pipeline were use in the experimental test to validate the developed inverse technique model. The inverse method showed a close relationship to the original pulse.
Design and Construction of a Spring Stiffness Testing Machine
(American Journal of Engineering Research (AJER), 2015) O. A. Olugboji; M. S. Abolarin; J. Y. Jiya; G. M. Alaya; C. K. Ajani
A spring stiffness testing machine was produced which differentiates a good spring from bad one using hydraulic principle and locally sourced materials were used to produce at relative low cost and high efficiency. It also categories each spring by stiffness into one of several distinct categories based on its performance under test. This is to ensure that in the final assembly process, springs with similar performance characteristics are mated to ensure a better ride, more précised handling and improved overall vehicle or equipment performance. The construction of the machine involves basically the fabrication process which includes such operation as cutting, benching, welding, grinding, drilling, machining, casting and screw fastening. Taken into consideration under test, were types of compression springs with varying spring loading and their different displacement recorded at different pressures to compare their stiffness.
Design and Fabrication of Rice De-Stoning Machine
(Food Science and Technology, 2014) O. A. Olugboji; J. Y. Jiya
This work aims at meeting the ever increasing demands of quality rice, avoiding losses and improving the income of local farmers. Mild steel was used in the construction of the machine. Standard equations were used to determine the dimension of the parts. The machine is driven by a 1Hp electric motor with 688.17 W required power. The machine has a capacity of 47.39 Kg/hr and an efficiency of 82.47 %
Design, Fabrication and Testing Of a Motorized Paper Perforation Machine
(International Journal of scientific research and management (IJSRM), 2015) J. Y. Jiya; M. S. Abolarin; O. A. Olugboji; R. I. Ngoffia; C. K. Ajani
This is concern with design and fabrication of a powered paper perforating machine with efficiency and less cost for bindery department in printing industries. It is a machine that will compete favorably with the manually operated ones and reduce human efforts with minimum time consumption. It perforates up to 15 sheets of paper at each stroke and is powered by a horse power electric motor whose rotational motion is converted to a reciprocating motion in the perforation pin by the principle of eccentricity.
Development of a Solar Water Distiller and Laboratory Analysis of the Product
(ABUAD Journal of Engineering Research and Development (AJERD), 2018) H. Adamu; O. A. Olugboji; O. Adedipe; J. Y. Jiya
In spite of the significance and availability of water, only an approximate value of about 1% is portable. Distillation processes which comprise evaporation and condensation in a box like machine called Solar Water Distiller was adopted for distilling unsafe to safe drinkable water in our homes. The design method adopted for the machine was energy method/balancing equation. The developed machine is a single stage distiller which is fabricated using local available materials. The heat energy required for powering the solar water distiller was 337.2 W/m2. This was the quantity of energy per unit time and area required for distilling the water based on average room temperature of 28.6 oC. The machine has capacity of average daily capacity of 28 litres as distillate water volume within 6.68 hours. It has design capacity of producing 4.2 litres per hour at minimum wind speed of 5.75m/s. The results show that produced machine has 75% efficiency with quality drinkable water that satisfied condition of Nigerian Standard for Drinking Water Quality NSDWQ (2007) rating.
Development of a Test Rig for the Determination of Headloss and Friction Factor of Polyvinyl Chloride (PVC) Pipes
(Journal of Energy Technologies and Policy, 2016) N. A. Musa; J. Y. Jiya; T. K. Aderoju
This paper reports the design, construction and performance evaluation of a test rig for determining the head loss and friction factor of PVC pipes of different diameters (13mm, 19mm and 25mm) transporting water. On performance evaluation, friction factors of 0.0121, 0.0396 , 0.0171 and head losses of 37.8mm, 25.2mm and 12.6mm for 13mm, 19mm, and 25mm diameter PVC pipes respectively were obtained. Keywords: Head loss, friction factor, PVC pipes, test rig, water
Effect of Cutting Speed and Feed Rate on Tool Wear Rate and Surface Roughness in Lathe Turning Process
(International Journal of Engineering Trends and Technology (IJETT), 2015) O. A. Olugboji; M. S. Abolarin; J. Y. Jiya; S. O. Popoola; C. K. Ajani
Machining is a vital part of the production process in the manufacturing industries. Turing operation was carried out on the mild steel to produce shaft of various diameters. The conditions applied during the turning operation include varying the cutting speed and feed rate while keeping other cutting variables like depth of cut constant. The results affirms that an increase in the cutting speed causes a decrease in the tool life, increase in the feed rate also affects the surface finish obtained.
EFFECTS OF OXIDIZED SUCROSE CROSS-LINKED CASSAVA STARCH FILM ON THE PHOTOVOLTAIC PROPERTIES OF PEROVSKITE SOLAR CELLS
(The Nigerian Institution of Mechanical Engineers (A Division of Nigerian Society of Engineers), 2021-09) J. Y. Jiya; J. S. Enaburekhan; M. T. Jimoh; E. C. Egwim; I. A. Joseph
Despite rapid progress in the perovskite solar cell efficiency, there have been concerns about issues which could affect the measurement accuracy and/or practical applications of these devices, amongst which are stability, scaling up (large area devices), and possible environmental effects related to the use of lead-based active material. Based on the findings from previous studies, an optimized biodegradable oxidized sucrose cross-linked cassava starch film layer with zirconium oxide is introduced as a desiccant and buffer against damp heat and thermal recycling. This modified photovoltaic device is capable of resisting ingress of moisture at elevated temperatures, withstanding temperature cycling without delamination, and as such, enables efficient and stable operation. The layers in the PSC were modified by replacing the conventional metallic counter electrode with a low-cost carbon counter electrode. The PSC device with the control architecture underwent a more rapid degradation, particularly within the first 288 hours though with a higher PCE than the modified device. However, in contrast, the PSC device with the buffer layer only degraded a small amount. The best device maintained 95% of its initial efficiency after exposure for 550 hours.
Event Reconstruction by Digital Filtering
(Horizon Research Publishing. Advances in Signal Processing, 2013) O. A. Olugboji; J. Y. Jiya; J. M. Hale
This work deals with a digital filtering technique that was developed to reconstruct a pulse after it has propagated along a pipe; a complex pulse that is progressively distorted. The technique developed makes use of the theory of digital filtering used in communications to remove distortion in long telephone links.
EVENT RECONSTRUCTION BY INVERSE METHODS
(2014) O. A. Olugboji; J. Y. Jiya
This work deals with an inversion technique that was developed to reconstruct a pulse after it has propagated along a pipe; a complex pulse that is progressively distorted as explained. The technique developed makes use of the theory of inverse problems
Gas Turbine Engine: Design, Application and Performance Analysis
(Springer Nature Singapore Pte Ltd. 2019 S.-I. Ao et al. (eds.), Transactions on Engineering Technologies,, 2019) A. Nasir; A. Mohammed; J. Y. Jiya
Gas Turbines (GT) are thermally rated air breathing engine which generates motive power from the combustion of fuel and expansion of gases. Gas turbines are employed in different spares of our daily lives, yet many people are unaware of the cutting-edge technologies used in the creation and operation of these engines. This article explains the principle involved with emphasis on the operation and performance analysis. The application of GT ranges from its use in power generation to aircraft propulsion, ship propulsion, gas compression in pipeline or tankers and others. GT is hugely affected by ambient conditions such as increase or decrease in ambient temperature. The operation of GT follows the Bryton cycle and detail is given in the paper. The effect of increase in ambient temperature on GT performance has been analyzed and discussed. As the ambient temperature increase, the mass flow reduces and therefore the performance of the GT drops.
Heat Transfer Analysis of a Concentrated-Type Solar Dryer for Ginger
(Journal of Science, GU J Sci, Part A,, 2024) I. Bori; J. Y. Jiya; A. M. Orah; S. Bako; M. O. Oyebamiji
In recent years, global concern about the preservation of agricultural products for usage and exports through drying has been outstanding. Solar Parabolic Trough Collectors (SPTC) are used to dry various agricultural products for effective moisture removal. A heat transfer fluid (HTF) flows through a receiver tube pipe that absorbs solar radiation reflected from the stainless-steel sheet surfaces of the SPTC. In order to reduce the heat losses, the pipe was linked through a flexible, thermally insulated cross-linked polyethene pipe to the copper tubes inside the drying chamber. The heat transfer analysis of the SPTC is essential to understand the thermal behavior and its performance during the drying process. This paper examined the heat exchanges developed in the designed concentrated-type solar dryer, and the heat transfer rates in the receiver tube and the drying chamber, as well as the heat transfer coefficients for the solar drying of ginger, were determined. The thermal analysis of the convective heat exchanges within the receiver tube and the drying chamber is presented. The heat transfer coefficients hRec and hDC for the convective heat transfer process in the receiver tube and the drying chamber were 1372.48W/m.K and 17.60W/m.K, respectively. The dryer’s thermal efficiency was 30%, showing considerable moisture removal from the ginger samples. The mean temperature difference between the drying chamber and the ambient showed a considerable increase of about +11oC. This resulted in considerable moisture removal, and the final moisture content achieved by the concentrated solar dryer for the ginger samples was 11.1%, compared to the 23.74% achieved by the open-air solar (OAS) drying method
INVESTIGATION OF MECHANICAL PROPERTIES OF POLYPROPYLENE FILM AS VACUUM PACKAGING MATERIAL FOR DRIED FISH
(ARID ZONE JOURNAL OF ENGINEERING, TECHNOLOGY & ENVIRONMENT (AZOJETE), 2023-09) I. A. Mohammed; O. Adedipe; J. Y. Jiya; A. B. Ayuba; K. T. Obanimomo; K. C. Bala
This study investigated the mechanical properties of three sets of polypropylene packaging films and existing dried fish packaging films and the quality of dried fish packaging in Nigeria... The polypropylene packaging films were produced in three batches A, B and C with thicknesses of 130μm, 150μm and 180μm respectively. The results showed that samples A, B and C had tensile strengths of 48N/mm2, 51.8N/mm2 and 61N/mm2 with Elongation at Break of 690.2%, 729.8% and 760% respectively. Also, the Dart Impact Strength of the samples were observed to be 191g/130μm, 208g/150μm and 231g/180μm respectively. Additionally, samples N and K (existing fish packaging films) had tensile strengths of 34.6N/mm2 and 31.2N/mm2 and Elongation at Break of 279.2% and 267.2% respectively. Furthermore, it was revealed that sample N exhibited better mechanical properties than sample K, while the produced polypropylene packaging films had the best mechanical properties among the samples tested. Using modern systems such as vacuum packaging and modified atmosphere packaging (MAP) techniques, fish packaging and storage was improved. This research is important in light of the significant increase in aquaculture activities in Nigeria due to increased fish production and government intervention in developing the sector, since it offers good moisture barrier properties, transparency and sealability with good cost efficiency and recyclability. It helps to preserve and protect the product’s quality, flavor and shelf life while providing a visually appealing package for consumers.
Investigation of Mechanical Properties of Polypropylene Film as Vacuum Packaging Material for Dried Fish
(Faculty of Engineering, University of Maiduguri, Maiduguri, Nigeria., 2023-09-01) I. A. Mohammed; O. Adedipe; J. Y. Jiya; A. B. Ayuba; K. T. Obanimomo; K. C. Bala
This study investigated the mechanical properties of three sets of polypropylene packaging films and existing dried fish packaging films and the quality of dried fish packaging in Nigeria... The polypropylene packaging films were produced in three batches A, B and C with thicknesses of 130μm, 150μm and 180μm respectively. The results showed that samples A, B and C had tensile strengths of 48N/mm2, 51.8N/mm2and 61N/mm2with Elongation at Break of 690.2%, 729.8% and 760% respectively. Also, the Dart Impact Strength of the samples were observed to be 191g/130μm, 208g/150μm and 231g/180μm respectively. Additionally, samples N and K (existing fish packaging films) had tensile strengths of 34.6N/mm2and 31.2N/mm2and Elongation at Break of 279.2% and 267.2% respectively. Furthermore, it was revealed that sample N exhibited better mechanical properties than sample K, while the produced polypropylene packaging films had the best mechanical properties among the samples tested. Using modern systems such as vacuum packaging and modified atmosphere packaging (MAP) techniques, fish packaging and storage was improved. This research is important in light of the significant increase in aquaculture activities in Nigeria due to increased fish production and government intervention in developing the sector, since it offers good moisture barrier properties, transparency and sealability with good cost efficiency and recyclability. It helps to preserve and protect the product’s quality, flavor and shelf life while providing a visually appealing package for consumers
PERFORMANCE ASSESSMENT OF HYDROPOWER GENERATING PLANTS
(International Engineering Conference (IEC), 2015) J. Y. Jiya; A. Nasir; H. U. Ogboo; A. Salihu
This paper studies the performance of ahydropower scheme in Nigeria which contributes to an acute electricity supplyand has effects on the country’s development. This does not only restrict the socioeconomic activities to basic human needs, but also adversely affecting the quality of life too.The expected full load installed capacity for the hydropower scheme is 522.74MW but the generated capacity for the period under review is 305.147MW. Only about 40% of the installed capacity was available. Average Capacity factor for this hydropower scheme is 47%, min. of 25% in 2014 and max. of 83% in 2013 as against the industrial best practice of 50 – 80%.Total generation reduction due to downtime of the hydropower scheme is 28165773MWh amounting to 53% of the total installed capacity. Based on Power generation reduction of 53% the loss of revenue in naira was about 186 Billion naira.To improve the annual power generation, a complete overhauling of all the generators and adequate water management practice must be in place so that the available water can sustain generation throughout the year.
Problem of calculating time delay between pulse arrivals
(American Journal of Engineering Research (AJER), 2015) O. A. Olugboji; J. Y. Jiya; C. K. Ajani
This work compares the performance of four different methods of estimating the time delay between pulse arrivals at the sensors subjected to different levels of attenuation, distortion and noise. The accuracy of the calculated time between the pulse arrivals at the sensors is determined and analysed for each of the methods based on the ideal attenuation (no change in shape), ideal attenuation with added noise to the pulse signal and ideal attenuation but with distortion. Based on the analysis carried out, it is clear the cross correlation method gives the best estimate of the delay in pulse arrival times irrespective of the signal to noise ratio and so is the preferred technique used in the remainder of this research.
Prototyping of a Robotic Fire Vehicle Using Radio Frequency Technology
(FUOYE Journal of Engineering and Technology,, 2019-03) O. A. Olugboji; J. Y. Jiya; I. D. Ogwuche
Fighting a raging fire is one of the toughest uphill battles in the public – safety world. Fire fighters try to put off fires with very little information, having no idea of the size and scope of the fire nor how many potential victims may be cut off from rescue (Na Gabbert, 2012). Fire losses throughout the world remain too high and firefighting too hazardous. This work aims to mitigate these losses via the prototyping of a robotic fire vehicle using radio frequency technology. The primary research method for this study is the literature review of the various types of limitation in existing firefighting systems and models, from the review carried out an improved firefighting robotic system was designed and built. The vehicle is loaded with a water carrying bottle. Two DC motors alongside a castor wheel are used for the locomotion and drive system of the robot, a DC water pump is used to spray jets of water through its suction action. These motors are controlled from a distance over a wireless communication between the Bluetooth HC-06 and a motor control app installed on an android phone. The Robot is programmed to stop and release sprinkles of water before the robot hits the target. An Arduino microcontroller is used for the overall desired operation. The entire system is powered by a 12V Lead – acid rechargeable battery. The robot has a dimension of 0.37 m by 0.28 m by 0.12 m and navigates through a modeled floor plan with an average velocity of 0.05 m/s to extinguish a simulated fire in 5 to 10 seconds. Experimental work has been carried out carefully and successfully, the proposed technique is confirmed to be very useful for engineering, research and safety purposes.
SECURITY MANAGEMENT: THE ENGINEERING PERSPECTIVE
(IEC, 2015) H. U. Ogboo; A. Nasir; J. Y. Jiya; H. T. Abdulkarim
Security management is a difficult task as everyone agrees that security is a problem. As such, this work aims at addressing the ever increasing security challenge confronting us as individuals from the engineering perspective. Throughout human history, engineering has driven the advance of civilization. This can be seen from the metallurgists who ended the Stone Age to the shipbuilders who united the world’s people through travels and trades; the past witnessed many marvels of engineering prowess. As civilization grew, it became pertinent that the world became confronted with the challenge of survival and relevance and hence, the desire not to be cut out from the basic necessities of life and existence gave rise to devices by humanity to remain relevance and hence, the field of engineering owes it a responsibility to the world to see that this issue is sorted out as usual as it has always provided respite to the world.
Statistical Optimization of Optical Property (Transparency) of Bleached, Oxidized Sucrose Cross-Linked Cassava Starch Film
(AFIT Journal of Science and Engineering Research, 2022) J. Y. Jiya; J. S. Enaburekhan; M. T. Jimoh; E. C. Egwim; I. A. Joseph
The present environmental pollution caused by non-degradable polymer films has prompted researches into the development of biodegradable polymer films. This study was able to develop a bleached, cross-linked film from native cassava starch. Hydrogen peroxide (H2O2) was added for bleaching to improve the transparency, oxidized sucrose was added for cross-linking and further oxidation while a moderated concentration of glycerol helps to improve the plasticity. In order to have a wider area of application of the film, the transparency was optimized using Box-Benkhen method under the response surface methodology (RSM) in Design Expert 11.0 software. UV-visible spectrophotometer analysis shows that the cassava starch film produced at the above process conditions retained 91.8 % of its transparency after 24 hours water immersion