bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of Monetary Challenges Affecting Operations of Private Tertiary Colleges in Nakuru Town, Kenya
Authors: Mugo A. N. 
Published: February 2022

Tertiary colleges are the institution in between the secondary and the universities. They are set aside for those students who fail to join universities due to failure of meeting entry points or lack of requisite fees. Most of these institutions are run by private sectors while a small percentage is run by public sectors. Due to various challenges here have been instances of monetary constraints in these institutions. This facilitated this study which hunted to evaluate the monetary challenges affecting operations of the private tertiary colleges. The study sought to establish the access of funds and credit facilities on operations of the aforestated private tertiary colleges. The pecking order theory guided the study. The study was conducted amongst private tertiary colleges in Nakuru town, Kenya. The study adopted descriptive research design with target population of 109 employees of these institutions. A census survey was conducted. The study employed a questionnaire to collect primary data. Data was processed and analyzed with the aid of the Statistical Package for Social Sciences software. Descriptive and inferential analyses were duly conducted. The findings indicated that access of funds and credit facilities affect operations of private tertiary colleges positively and that the relationship between the two constructs is statistically significant (r = 0.665; p < 0.01). The study concluded that the role played by funds and credit facilities in the Operations of private tertiary colleges cannot be understated. It is recommended that the management of private tertiary colleges should devise various sources of funding such as initiating income-generating projects and liaise with corporate entities for sponsorship of needy students.
Thermo-economic Analysis of a Retrofit Small Scale Municipal Solid Waste Power Plant
Authors: Nkoi Barinyima , Koate Confidence , Hart Howells Idaerefagha 
Published: February 2022

This paper evaluates the thermo-economics of a retrofit small scale municipal solid waste (MSW)-fueled power plant in Port Harcourt, Rivers State, Nigeria. The design parameters for the combustion chamber which utilizes mass combustion in stoker crate furnace is operated at steam saturation pressure of 38.2bar, with fuel consumption rate of 41.3tonnes/hr (11.88kg/s) and was selected for the amount of MSW generated in Port Harcourt metropolis. The data used to assess the availability of the fuel (MSW) were obtained from waste dumpsites controlled by Rivers State Waste Management Agency (RIWAMA). MATLAB Software modeling was used for the thermodynamic analysis to appropriately retrofit a steam turbine to the selected combustor and the result show that the optimal performance of the proposed MSW plant gives a net power output of 5.23MW. The result further shows that heat in the steam entering the turbine is equivalent to 0.71MWh per tonnes of waste. Therefore, at 17.3% thermal efficiency of the proposed MSW plant, 0.13 MWh of electricity will be produced per tonnes of waste combusted. However, it is estimated that the plant may consume 15% of the electricity, which implies that 0.11MWh/tonne will be exported to the grid. Thus, as the plant is expected to process 340770.3tonnes/yr of MSW, the net electricity output of the proposed plant is estimated at 37.48GWh per year. The economic evaluations have shown that the Net present worth of the plant is $6395107.07 with a payback period of 7years for a 20years life cycle. This work thus indicates huge potentials in generating electrical energy and wealth from MSW in Port Harcourt and beyond with the use of cheap and readily available fuel from municipal solid waste.
Design and Fabrication of a Modified Portable Biogas Digester for Renewable Cooking-Gas Production
Authors: Nkoi Barinyima , Lebele-Alawa Barinadaa Thaddeus , Odobeatu Benedict 
Published: February 2022

This research paper focuses on re-engineering design and fabrication of a modified potable biogas digester for the production of biogas as a renewable energy source for domestic use. Digesters used around the world are commonly big in size. There is need to modify and re-engineer an existing biogas digester to fit in to modern day design for better efficiency, portability and safety. Floating drum and Flexible balloon are digesters to be modified as a thin walled pressure vessel with radius-thickness ratio greater than 10. ASME codes and standards were used to carry out the sizing calculations, thickness and pressure calculations for the cylindrical pressure vessel shells and also calculations for the storage tank hemisphere shell. AISI 304 (Chromium-Nickel steel) is used for the vessel shell and the maximum allowable stress is 137 MPa. Weld efficiency (85%), corrosion allowance (0.02mm), of 24 (for digester), of 18 (for collector) and of 20 (storage tank). 17 kg of cow dung and 34 kg of water with temperature of 32oC were the raw materials used for this research to produce a cumulative gas volume of 0.1243 m3 for 30 days. Furthermore, a bike pump is modified and used to increase methane gas pressure from 4.903 kPa to 345 kPa to suit the modern day gas cookers design and storage tank. Unlike other biogas plant, an electronic smoke alarm detector (model: Ei100) is placed 300 mm below the digester top for effective fire protection. Series of tests were performed to ensure that the constructed prototype met the specifications/standards. Such test include, smoke detector test, pressure testing, gas leak test, and a unit test run also confirmed that the aim of research was achieved.
Case Study of building Storage Strategy in the Logistics Distribution Center—Logistics Company A as an Example
Authors: Kao Ching-Kuei , Xu Guo-Xia , Fang Xiao-Er , Zheng Mei-Chun 
Published: February 2022

Storage and maintenance are essential in warehouse operation management. Accordingly, this study takes a logistics distribution center as the case. In this case, Logistics Company A and X Beverage Company establish a logistics partnership in the supply chain. Logistics Company A is responsible for designing and handling X Beverage Company’s cargo storage, transportation, and distribution businesses in big and small retail shops in Y region. Reducing the goods overstock, stock, and stock-out rate and improving the goods’ freshness are important because beverages are classified as fast-moving consumer goods. This study develops the storage strategy for goods in X Beverage Company through classified management of goods by activity-based classification (ABC) with the primary aim of increasing the efficiency of storage management. Second, goods stock and management strategies are developed with the aid of EIQ (entry, item, and quantity) analysis and in accordance with results of the ABC classification. Finally, the EOQ (economic ordering quantity) stock control model is established for large retailers and small retail stores.
Corrosion Effects on Residual Structural Capacity of Resins / Exudates Inhibited Steel Reinforcement Flexural Beam
Authors: Kennedy Charles , Paulinus Akpan Paul , Kabari Gbinu Samuel 
Published: February 2022

The study investigated the effects of corrosion on the residual structural steel bar capacity of resins/exudates inhibited and non-inhibited reinforced concrete beam members. Steel reinforcements were coated with moringa oleifera lam resins/exudates from trees extract (Inorganic inhibitors), embedded into concrete beam members and exposed to sodium chloride medium representing laboratory harsh saline marine environment. Corrosion acceleration potential test was conducted on 27 samples of non-corroded, uncoated and coated resins/exudates paste thicknesses of steel bar and simulated for 60 days, after 30 days, initial concrete cured. Results obtained showed corrosion potential presence on uncoated members with cracks and spalling. Further recorded results on non-corroded flexural strength test of failure load 29.09%, midspan deflection 28.30%, tensile strength 12.03% and elongation 31.50%, for coated beam members, failure load 29.42%, midspan deflection 27.42%, tensile strength 12.09% and elongation 31.80%, for corroded beam members, failure load decreased by 22.50%, midspan deflection increased by 39.30%, tensile strength decreased to 10.17% and elongation by increased 46.30%. The entire experimental results showed that corroded specimens has lower flexural load, higher midspan deflection, lower tensile strength and higher elongation due to loss of steel bar fibre from degradation effect from corrosion, inhibitors served as protective coating against corrosion, but no strength was added to steel members.
Comparative Analysis of Free Natural Convection Heat Transfer on Rectangular and Triangular Fins with and without Perforation
Authors: Andrew Ogie Nosa , Oyejide Joel Oluwayomi 
Published: February 2022

The importance of heat transfer by free natural convection can be found in many engineering application such as energy transfer in buildings, solar collectors, nuclear reactors and electronic packaging. In this research work, we carried out the investigation and comparative analysis of heat transfer by natural convection on rectangular and triangular fins with and without circular perforation. A total of six (6) specimens were used. Other materials that were used in this research work include four digital thermometers, one heating element, four thermocouple K-type and a power source. The fins used in this research work were welded to a cylindrical pipe which served as the heat sink. The heat supplied was maintained at 2500C and the temperature drop through the fin was recorded for duration of 30minutes with intervals of 5minutes. It was observed that the temperature dropped more rapidly with the triangular fins than the rectangular fin. Also, the rate of heat dissipation increase with a corresponding increase in the number of perforation.
Enhancement of Heat Transfer in a Rouletted Copper Tube Employing Delta Winglet Twirled Type Insert
Authors: Hossain Mohammad Taukir , Ali Nesar , Karim Muhammad Sadekul 
Published: February 2022

Heat transfer is a process or a system of thermal engineering that concerns the generation, use, conversion, transfer, internal or external molecular formation and exchange of thermal energy (heat) between physical systems. The research work has been experimented for the turbulent flow heat transfer in a tube having delta winglet twisted tape and then separately with water as working fluid. The test section consisted of a circular copper tube of 26.6 mm inner diameter, 900 mm length with five K-type thermocouples. Bulk temperature and pressure drops have been measured. Material of both the delta winglet twisted tape insert was stainless steel. Delta winglet twisted tape insert had a length of 795mm, width of 20mm, thickness of 2mm, pitch length of 120mm, twist ratio of 6 while wire coil insert had the same length as that of delta winglet twisted tape insert, wire diameter of 1mm, mean coil diameter of 22mm and pitch length of 30mm. Heat transfer rate, convective heat transfer coefficient, Nusselt’s number, friction factor and heat transfer efficiency have been calculated to analyze heat transfer performance of circular copper tube fitted with or without inserts in turbulent regimes (4000<Re<15000). Nusselt’s numbers for combination of delta winglet twisted tape and wire coil insert, wire coil insert only, delta winglet twisted tape insert only increased by 1.29 to 1.47, 1.19 to 1.34 and 1.10 to 1.15 times respectively than the plain tube. They increased by 17.95% to 27.61%, 15.97% to 20.20%, 8.90% to 12.02% and average of 21.65%, 17.44%, 8.95% respectively than the plain tube. Heat transfer rates also increased by 1.12 to 1.20, 1.06 to 1.09 and 1.03 to 1.05 times respectively compared to the plain tube. Heat transfer efficiencies increased by 1.36% to 1.62%, 1.24% to 1.47% and 1.14% to 1.34% respectively compared to the plain tube. Friction factors increased by 1.44 to 1.62, 1.34 to 1.43, 1.22 to 1.27 times respectively compared to the plain tube. The delta winglet twisted tape was the best arrangement for the enhancement of heat transfer rate as compared to the other inserts.
Comparative Energy and Exergy Analysis of a Thermal Power Plant With/Without Retrofitted Inlet Air Cooler: A Case Study
Authors: Aliu Sufianu Adeiza , Ochornma Promise Ijeoma 
Published: February 2022

The result of this study shows the performance of Ihovbor Gas Power Plant in Benin, Edo State Nigeria using first and second law of thermodynamics. Analysing the efficiency of the plant using first law of thermodynamics showed that with increase in inlet air temperature, the energy conversion efficiency of the plant reduces. The exergy efficiency of the plant also confirmed that increase in inlet air temperature results in decrease of the exergetic efficiency of the plant. Analysis of each of the components showed the greatest destruction of exergy was in the combustion chamber while the least is the Gas turbine section. Using numerical method in analyzing the gas turbine plant when retrofitting with an evaporative inlet air cooler showed better performance in energy conversion as power generation increased with an average of 1% per 1oC degree fall in temperature, the work ratio and thermal efficiency of the plant also increased. The analysis of the modified plant using second law of thermodynamics showed an increase in magnitude of both the exergy destroyed and the efficiency of the plant. Analysis showed that integrating evaporative cooler as component of the inlet air cooler increases the efficiency of the Air compressor by over 0.8% thus increasing the plant’s exergetic efficiency.
A Hybrid Model of Artificial Neural Network and Genetic Algorithm in Forecasting Gold Price
Authors: Khamis Azme bin , Yee Phang Hou 
Published: February 2022

The goal of this study is to compare the forecasting performance of classical artificial neural network and the hybrid model of artificial neural network and genetic algorithm. The time series data used is the monthly gold price per troy ounce in USD from year 1987 to 2016. A conventional artificial neural network trained by back propagation algorithm and the hybrid forecasting model of artificial neural network and genetic algorithms are proposed. Genetic algorithm is used to optimize the of artificial neural network neurons. Three forecasting accuracy measures which are mean absolute error, root mean squared error and mean absolute percentage error are used to compare the accuracy of artificial neural network forecasting and hybrid of artificial neural network and genetic algorithm forecasting model. Fitness of the model is compared by using coefficient of determination. The hybrid model of artificial neural network is suggested to be used as it is outperformed the classical artificial neural network in the sense of forecasting accuracy because its coefficient of determination is higher than conventional artificial neural network by 1.14%. The hybrid model of artificial neural network and genetic algorithms has better forecasting accuracy as the mean absolute error, root mean squared error and mean absolute percentage error is lower than the artificial neural network forecasting model.
Comparative Assessment of Thermal Power Systems Performance Under Uncertainty
Authors: Kpegele Le-ol Anthony , Adumene Sidum , Israel Kenneth 
Published: February 2022

This work presents a comparative analysis of the thermo-economic performance of a simple, retrofitted and built-in combined cycle power plants within the Delta. The data were obtained from a 25MW gas turbine plant-based engine, retrofitted and MATLAB software was used to model the thermodynamic performance of the plants. The economic prediction of the plants was done using a developed net present value(NPV), internal rate of return (IRR), cost of investment (COR) and payback period (PBP). The economic concept for plants performance was analysed under uncertainty constraints of energy need, operating conditions, energy cost and energy supply variability. Three plants configuration; simple gas turbine (SGT), retrofitted combined cycle (RCC) and Built-in combined cycle (BCC) was analysed based on these economic performance indicators. The three configurations show a positive NPV, PBP and IRR, with the BCC showing the optimum return on investment. Although the RCC show minimum initial cost on investment compare to BCC, the BCC demonstrates greater overall return with an NPV of $30,755,454.18, IRR of 17.1% and PBP of 6.3years for the period of 20years. The analysis shows cash flow of 34.1% and 52.6% for the RCC and BCC respectively. The result also showed that the plant performs better at a lower ambient temperature and higher relative humidity with a higher return on investment. This research provides great insight into the thermo-economic analysis, and benefits of combined cycle power plant and will aid energy system investors on the choice of the power plant for power generation in the Niger Delta.
Economic Analysis of a Grid Connected PV Systems: A Case Study in Khulna
Authors: Podder Amit Kumer , Hasan Md. Rakibul , Roy Naruttam Kumar , Komol Md. Mostafizur Rahman 
Published: February 2022

This paper presents a detailed design of an on-grid PV system that meets the electrical needs of a typical domestic building in the southern corner (i.e. Khulna) of Bangladesh. The system comprising of the photovoltaic array to capture solar energy, a power converter to change over between AC and DC, grid connection and lead acid battery to store energy. The modelling is completed by assessing the required load, choosing and deciding the proper specifications of the components associated with the system. Different factors, for example, the geographic area, atmospheric condition, solar irradiance and load consumption upon which the whole work depends are all considered. The cost optimization of the system is performed as per the system’s net present cost, cost of energy, operating expense and initial capital. Additionally, an efficient algorithm to manage the system energy along with power flow is proposed. The techno-economic analysis of the proposed system is performed by using HOMER simulation software. Simulated results indicate that the proposed model meet the load demand and show tasteful execution.
Study on the Catalytic Effect of Nitric Acid Activated Myanmar Natural Clay for the Degradation of Plastic Wastes
Authors: Thant Amie , Hmwe Chaw Su Su 
Published: February 2022

In this study, the performance of different acid treated Myanmar Natural Clay (Mabisian) was conducted the pyrolysis of mixed plastic wastes, 40% high density polyethylene, 30% polypropylene, 25% low density polyethylene and 5% polystyrene. Mabisian clay was refluxed with different concentration of nitric acid (2M, 4M, 6M, 8M, 10M, 12M and 14M) at 100ºC for 3hrs followed by calcination at 500ºC for 1hr. The physico-chemical characteristics of resulted leached clay were studied by X-Ray Fluoresence spectroscopy (XRF), X-Ray Diffraction (XRD) and Fourier Transformed Infrared Spectroscopy (FTIR). The pyrolytic oil was characterized by Gas Chromatography – mass spectopy (GC-MS). XRF and FTIR studies indicated that acid treatment under reflux condition lead to the removal of octahedral Al3+ cations along with other impurities. The chemical treatment increased the Si/Al ratio. The maximum liquid yield (75%) was obtained at 12 M nitric acid, 3hr reaction time and 100 º C reaction temperatures. In addition, the percent peak area of gasoline range hydrocarbon was obtained 55.6% at optimum condition. Thus, the treated clay can be used as promising as catalyst support.
Determination of Species Concentrations of Ti-6Al-4V Titanium Alloys using Calibration Free Laser Induced Breakdown Spectroscopy
Authors: Hamad Tagreed K. , Salloom Hussein Thamer 
Published: February 2022

In this study, Calibration-free Laser-induced breakdown spectroscopy (CF-LIBS) was applied to quantitatively analyze the elemental composition of Ti-6Al-4V titanium based alloy samples with no need for matrix-matched calibration procedure. Nd:YAG pulsed laser operating at a wavelength of 1064 nm was focused onto the sample to generate plasma. The spectrum of plasma was recorded using spectrophotometer then compared to NIST spectral lines to determine characteristic wavelengths, energy levels and other spectroscopic parameters. The values of plasma temperature obtained using Boltzmann plot for four examined samples ranged from 7439 to 6826 K while the electron density for each element was determined using Boltzmann-Saha equation. The concentration of Ti, Al, V and Fe has been determined and were within the samples nominal concentrations obtained from XRF analysis. The calculated average relative errors of Ti, Al, V and Fe were 0.39%, 4.38%, 4.94 % and 8.2 %, respectively. Finally, there was a direct proportionality relation between the ratio of ionic to neutral emission lines of Ti for four samples and the surface hardness values measured mechanically using Vickers hardness test. The ratio at had the best linear regression value (R2=0.95) which indicates the best correlation with surface hardness.
Vibration Protection of Mechanical Systems Consisting of Solid And Deformable Bodies
Authors: Safarov Ismail Ibrahimovich , Khudoyberdiyevich Teshaev Muhsin 
Published: February 2022

In this paper active vibration protection of mechanical systems consisting of solid and deformable bodies is considered. To actively control the oscillations of dissipative mechanical systems, a constructive method is used to determine the structure of the reaction forces of servo constraints. As an example, we consider the system with a finite number of degrees of freedom. Numerical results for various harmonic are also given.
Decentralized Control Technique Application for Effective Energy Management in Microgird Network
Authors: Omorogiuwa Eseosa , Enebieyi Martins William 
Published: February 2022

Micro-grid supplied by Renewable Energy Sources is characterized by randomness and intermittency due to varying weather conditions. Moreover, increasing demand for off-Grid electricity lead to uneven expansion of Micro-grid structures which may attract additional cost due to complex communication requirements in centralized Systems. In view of the above problems, decentralized control technique is employed in this work to effectively improve energy supplied to an inverter-Based Micro grid by Solar PV and Battery. Droop-based PWM control technique is applied to low Voltage Micro grid at a reference location for effective Energy Management Improvement. Simulations of various operating modes and weather conditions are done in MATLAB/Simulink to validate energy management improvement system. Results obtained showed that active and reactive power is shared between Inverter-connected Energy sources according to their Voltage ratings in Islanded Mode. Coordination technique of energy Management Improvement System supports true Plug and Play Functionalities as DGs can be added to the network with varying voltage Magnitude and location without pre-configuration.