Table of contents

One of the ways to combat food insecurity as world population rises is the reduction of food losses. Drying is one of the oldest methods of food preservation and hence reduces food losses. Solar drying uses energy from the sun and an absorber material to carry out drying of produce. In this project, a solar dryer was designed, constructed and its performance was evaluated. The dryer has overall dimensions of 1000mm by 410mm by 700mm. The inner part of the dryer compartment was lagged with aluminum foil to act as an insulator. The solar collector made of galvanized sheet and the glass on top of it have an area of 800mm by 380mm. Fresh scotch bonnet pepper was used as the produce of choice. The pepper was dried in 2 experiments for 3 weeks each. 200g of pepper was used and weighed to measure weight loss periodically. Temperature and humidity of the drying chamber and the surrounding were measured with data loggers throughout the periods of the experiments. The results showed that the ambient temperature during the experiments was higher than the temperature of the drying chamber in the early hours of the morning between 4am and 10am. During every other period, the temperature in the drying chambers was higher than the ambient temperature. An average moisture content of 81.3% w.b. was removed from the pepper during the experiments. The average efficiency of the dryer was 28.4%.

Due to the aspirations of various institutional stakeholders clamoring for improvement in the quality of education in their various institutions, the concept of total quality management has gained so much attention to this regard. In the recent time, several emphases have been made on the need for quality improvement and efforts are been put in place on the possible ways of increasing the standard of education globally. The productivity of any tertiary institution, especially the Engineering colleges is centered on the quality culture of such institutions, also, the customer's satisfaction is another thing to put into consideration, to achieve the desired productivity. Generally, there are some constructs which are the major critical success factors that enhances quality improvement in any organization, customer satisfaction has been identified as another important factor to put into consideration to achieve optimum quality of products as well as services. This paper gives an insight on how the implementation of Total Quality Management in an Engineering educational system can aid the Quality of Engineering Education.

In traditional irrigation approach where water is irrigated on the land without adequate control measures, crops sometimes undergo increased stress with disparities in the soil moisture which consequently reduce the crop performance and output. In this paper, we come up with a prototype to increase crop yield while considering adequate agricultural water management and labour reduction, by adequate control measures in the irrigation process. An automatic irrigation system is designed and developed by integrating several hardware and software features. The system is designed to determine when exactly the soil of crops need water and deliver a controlled amount of water to the root zone of the crops based on the soil moisture state. With the microcontroller, the data obtained from the soil at the roots of the crops will determined how much water for irrigation is needed at a point in time, and supplies it, thereby incorporating good water management practice. The system is designed to run 24/7 on renewable solar energy.

The Schmidt rebound hammer is principally a surface hardness tester with an apparent theoretical relationship between the strength of hardened concrete block and the rebound number of the hammer. This study analysed compressive strength of some selected concrete columns of Civil Engineering block at Covenant University Ota, using the Schmidt rebound hammer. It is aimed at determining variation in the concrete column strength of the HEI building in relation to standard compressive strength required of a concrete column. Data for the study was collected by carrying our Schmidt rebound hammer test (non-destructive test) on the concrete column within the study area and the rebound value (R) was measured to determine the present compressive strength of the concrete column. In carrying out this experiment, the standard experiment procedure of the Schmidt hammer test was followed. The analysis of the performed nondestructive test on the HEI concrete column was presented through tables and figures. The result of the study shows that there is variation in the compressive strength of the HEI concrete columns sampled using Schmidt rebound hammer test. The result indicated that the average compressive strength gotten through the rebound values of the sampled concrete columns compressive strength falls within the minimum required strength between 25N/mm² and 30N/mm² expected of a concrete column of an existing structure. The study therefore, concluded that the concrete columns of the HEI building sampled is safe, stable and it can satisfy the need for which it was built. Furthermore, because of it stability it can resist the load coming to it and this make it habitable for learning.

The manufacturing sectors of nation's economies have without doubt been noted as the chief driver of economic growth the world over. The connection between the Nigerian manufacturing sector and foreign direct investment (FDI) was assessed in this work. The study, in order to empirically examine how the variables are related in the long term and short term, utilised time series data spanning 36 years, while the autoregressive distributed lag (ARDL) and co-integration technique were used. From the result, it is seen that the dependent variables explained R² of 97% of the variations in manufacturing sector indicators (MFI), while Foreign direct investment, (FDI), Inflation rate (INF), government expenditure (GOE), and money supply (MSP) represent the independent variables. One of the recommendations of the study is that the federal government should consciously increase amount of foreign direct investments (FDI) made available to this all-important sector-manufacturing sector to boost its efficiency especially with respect to percentage impact on GDP and employment generation in Nigeria.

Mechatronics has found quite a number of useful applications in agriculture. Agriculture as one of the oldest industries, dating as far back as the nomadic age originally depended solely on human effort, then apprehended animal labour, and then came mechanical advances such as diesel/steam-engine tractors and mechanical tools with hydrostatic power which needed control. The answer to unresolved problems relies on more advances that necessitate the replacement of human intellect to meet the requirements for superior autonomy in more indefinite and unstructured environments. Promising disciplines in this framework include Mechatronics, Large-scale optimization and Complex system automation, and our focus is on the advancement of irrigation system. Some of the applications of mechatronics in agriculture and their processes are discussed to gain insight on the state of the art, advantages and weaknesses of several methods employed.

This research work assessed wood and plastic in building construction. The study was a descriptive survey design and as such made use of questionnaire with 42 items. The Population of the study was 110 respondent which include 40 building professional and 70 non-building professional. The data were analyzed using mean and standard deviation. T-test was used to test the null hypothesis at 0.05 level of significant. The finding of the study shows that plastic work form can be used for casting slab, concrete wall among others. The finding also revealed some factors that determines the selection of form work such as climatic condition, labour efficiency and that plastic formwork saves cost as a result of long reuse period. It is therefore recommended that; plastic and wooden formwork should be integrated often in the casting of slabs, beam and columns without discrimination, proper adherence to standards and specifications for use of any type of formwork, there should be large scale production of plastic formwork to conserve forest and wood, factors to be considered in the selection of formwork should not be ignored, there should be proper weighing of the advantages and disadvantages of each type of formwork relating to the scale of construction before the choice of any formwork.

The quest for energy from renewable and sustainable sources has led to the investment on exploration and installations of wind energy systems to harness energy from wind for use by mankind. Various wind energy systems exist and they are quite expensive. Selections of appropriate systems for installation are dependent on the wind power available in a location. It is therefore important that proper wind assessment is done before investments on infrastructures for harnessing wind power are put in place. Wind data between 2014 and 2018 were obtained from the Landmark University Weather Station in Omu Aran and the pattern of wind speed distribution in the location over the years in focus were determined by the Weibull function. The power law was used to estimate the wind speeds at heights of 10 and 20 metres respectively. Recommendations on appropriate wind energy systems suitable for Omu Aran region were made based on the wind speed pattern.

The sensible storage system utilizing a hot and cold tank is the current commercial technology for solar parabolic trough thermal plants. This technology is very expensive, because of its large storage material requirement, two tanks and heat exchanger. It also has high parasitics. The use of phase change material (PCM) offer higher storage capacity per unit mass. The wide operating temperature range (about 100°C) in parabolic trough plants meant that many PCMs with different melting points in series must be used. Investigation of using five PCMs with different melting point resulted into a storage system with storage material inventory higher than that of the two-tank system due to slow discharging rates. In this study, a multistage finned latent heat storage system model was developed and performance analysis was conducted. A model was developed for a four (NaNO3, KNO3/KCl, KNO3 and KOH PCMs) and five (NaNO3, KNO3/KCl, KNO3, KOH and MgCl₂/KCl PCMs) stage cascaded storage system. Various charging and discharging mass flow rates were simulated and for each mass flow rate, the length of the storage system that will satisfy the boundary conditions of the plant at a periodically balanced state was determined. Results showed that using A HTF charging and discharging mass flow rate of 0.025kg/s and 0.03kg/s respectively has the highest percentage phase change of 70% meaning better utilization of storage material. Also the four stage cascade was found to have a percentage phase change of 56% which is lower than that of the five stage cascade. Considering a capacity of 875MWh_th, which is the capacity suitable for the 6 hours operation of a 50MW_e parabolic trough plant, a storage material inventory of about 25, 000 tonnes is required corresponding to a net volumetric specific capacity of 72.8 kWh/m³ which is about 2.5 times that of the existing two tank system. This clearly shows the higher storage density of the multi-stage finned LHS system. The LHS system is passive and thus has very low parasitics compared to the two-tank system.

Carcinoma of the Lung is one of the most common cancers in the world and the leading cause of tumor-related deaths. Less than 15% of patients survive 5 years post diagnosis due to its relatively poor prognosis. This has been ascribed to lack of effective diagnostic methods for early detection. Different medical imaging techniques such as chest radiography, Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) are used in routine clinical practice for tumor detection. These techniques are medically unsatisfactory and inconvenient for patients due to poor diagnostic accuracy. Endobronchial biopsies are the gold standard for diagnosis but have the inherent risk of full or partial invasive procedures. Thus, diagnostic technology that uses data mining algorithms with medical image analysis, generally known as radiomics emerged. Radiomics extracts complex information from conventional radiographic images and quantitatively correlates image features with diagnostic and therapeutic outcomes. In spite of the benefits, radiomics is prone to high false positives and there is no established standard for acquisition of parameters. Further efforts towards outcome improvement led to the proteomic and genomic (proteogenomic) approach to lung cancer detection. Although proteogenomic has a diagnostic edge over traditional techniques, variations in bio-specimen and heterogeneity of lung cancer still possess a major challenge. Recent findings have established that changes normally occur in the gene or protein due to tumor growth in the lungs and this often leads to peroxidation of cell membrane that releases Volatile Organic Compounds (VOCs) through the breath of Lung Cancer patients. The comprehensive analysis of breath VOCs, which is tagged Breathomics in the literature, unveils opportunities for noninvasive biomarker discovery towards early detection. Breathomics has therefore become the current pace-setter in medical diagnostics research because of its non-invasiveness and cost effectiveness. This paper presents a mini survey of trends in early lung cancer detection from radiomics, through proteogenomic to breathomics.

One of the goals of Word Bank's Identification for Development (ID4D) is the realization of robust digital identification systems as a means of sustainable development priority. ID4D's most recent report shows about 1.1 billion of the world's population are yet to be identified for development. Africa represents about half of that number while Nigeria represents about a quarter of Africa's share. Biometrics is the state-of-the-art approach for identification using human behavioral and/or physiological digitally calibrated traits and one such trait is the voice. The backbone of biometric research is the database employed in the design of biometric systems. Although many voice databases are publicly available such as the THCHS-30 for Chinese and Microsoft Indian language Speech Corpus for Indians, none is currently publicly available or free for Nigerians. The creation of such an indigenous database (or corpus) can open doors to Nigerian automatic speaker recognition as well as for indigenous language, ethnicity, gender, age group and emotion classification amongst others. This work is a first step in the direction of creating a Nigerian Voice Corpus (NVC) to aid indigenous voice biometric research. A voice corpus of popular Nigerians was created by curation of audio samples of 14 women and 23 men from YouTube. The corpus contains 10 different samples of 5 seconds duration for each individual resulting in a total of 370 samples. The created corpus was used to carry out speaker recognition experiment by dividing the audio samples into 25ms non-overlapping frame durations. Silent frames were excluded using short-term spectral energy threshold for Voice Activity Detection (VAD). This was followed by extraction of Mel Frequency Cepstral Coefficient (MFCC) as descriptors to discriminate different speakers using Support Vector Machine (SVM) with median Gaussian function. An overall recognition accuracy of 93.24% was achieved demonstrating the feasibility and research potential in this direction.

In the construction industry, an aggregate is an important material used in the production of concrete. The strength of any building component, constructed using concrete will depend on the type and texture of aggregates used. It is on this base that this study analysed two different types of coarse aggregate (crushed granite and washed gravel) used in the production of concrete for higher educational institution (HEI) buildings. The following experimental procedures such as silt content, water absorption, specific gravity, sieve analysis, were conducted on the aggregates sampled to determine the property quality of the aggregates when used with other adhesive. Concrete of ratio 1:2:4 were produced using crushed granite and the washed gravel sampled and its strength was tested with the compressive strength testing machine. The 28 days average compressive test of concrete produced with crushed granite and washed gravel are 23.36 N/mm² and 20.44N/mm² respectively. The study suggests that locally sourced gravel should be washed before use to reduced silt content and impurities in the coarse aggregate. The study concludes that base on the compressive strength result of the study both crushed granite and washed gravel can be used for concrete work in construction work or project, but their selection for usage should be based on expected imposed load.

The fabrication of a rapid compression machine (RCM) is in its early phase of design. The machine is designed to enhance the study of ignition delay and validation of detailed kinetics models of fuels. The machine compresses fuel/air mixtures isentropically within 25 to 52 ms with a varying stroke. The combustion chamber design is not fixed and can be adjusted through the threaded shaft lock and within chamber slots. The originality of the facility is the inclusion of a pneumatic piston release mechanism (PPRM), which is pneumatically operated. The current test facility has been characterised by conducting a nonreactive and reactive experiment, the result showed that an obtainable compressed pressure of 21 bar and end gas temperature of approximately 1000 K was achievable within the present facility. The fidelity of the facility was performed with a non-reactive experiment, which experimental pressure profile was seen to follow each other closely showing that the data are highly repeatable within the test condition, the result was free from any form of rebound or disturbance, which would have adversely distort the result. The experiment data was simulated implementing the effective volume approach and was seen to perfectly match with the experiment at both stages of compression. The reactive experiment was demonstrated with heptane/air mixture at stoichiometric condition, T_C = 625 ⩽ 689 K. The results show that the experimental pressure traces overlay each other thus signifying a repeatable pressure trace and this demonstrates that the Shef-RCM is operable and ready at its first stage of design for studying the ignition delay time of liquid fuels operating within an engine like conditions and for validating chemical kinetics models.

Estimating human gender from faces in images is an important area of research as many applications rely on it. Facial recognition is a branch of biometrics that uses the face which is a physical trait to uniquely identify individuals. Gender recognition using face analysis is also an important task in computer vision as it helps in visual surveillance, intelligent user interfaces, demographic studies etc. The fundamental of gender recognition and other similar classification problem is broken into four stages i.e. the image to be examined to the pre – processing of the image, feature extraction and lastly classification. Several approaches including the deep learning approach which is a representation of the learning procedure that discover multiple levels of representations using neural network has been explored for gender recognition. This work is essential in creating a face-based recognition for gender analysis for Nigerians. The face database consists of over 6000 images of Nigerians with different variations. The created database was used to analyze gender by pre-processing the images, extracting necessary features and classification using the Convolutional Neural Network (CNN). An overall recognition accuracy of 98.72% was achieved demonstrating the feasibility and research potential in such direction.

The concept of big data though relatively new has brought a lot of solutions to modern day challenges. Many authors, particularly in developed countries, have adopted the concept in tackling the numerous challenges unfolding in the real estate profession. However, most of the findings from these authors are on individual bases and as such, there is a need to reach a general consensus on the relevance of big data to the real estate profession. The review shows the impact of big data to include digitization of records, information on user preferences, sensor information on the urban environment and sensor information on movement. The paper concludes that the relevance of big data to the real estate profession cannot be over-emphasised.

Zeolites are important industrial materials of unique chemical structure that are utilized in various industrial plants as adsorbent for gases, liquid, solids or even as catalysts. The use of synthetic chemicals as starting materials for commercial production of Zeolite-A is cost intensive. However, low-cost raw materials such as clay minerals, coal ashes, natural zeolites, municipal solid wastes and industrial sludge have been widely used. In this study, the synthesis and characterization of Zeolite-A from natural raw Kaolin (Elefun) clay using hydrothermal treatment technique was investigated. The raw and beneficiated kaolin were experimentally studied and comparison was made based on material characterization and application. Metakaolinization was achieved by thermal activation of the beneficiated kaolin at 850 oC for 2 hours. Thereafter, Sodium Aluminosilicate gel was prepared with the molar ratio SiO₂/Al₂O₃ = 2.6, Na₂O/SiO₂ = 3.0, and H₂O/Na₂O = 40 by mixing calculated amounts of metakaolin with sodium hydroxide solution of analytical grade. The gelled samples were aged for 24 hours at ambient temperature and subsequently crystallized for 24 hours at 100 °C. The starting kaolin, beneficiated kaolin, calcined kaolin and final product were characterized using X- Ray Fluorescence (XRF) and results were corroborated by X-Ray Diffractometer (XRD) and Scanning Electronic Microscope (SEM). The results showed that Zeolite-A can be synthesized from Elefun kaolin by ageing at room temperature for 24 hours and crystallization at 100 ° C for 24 hours.

The need for a sustainable energy has given rise to the search for a renewable source of energy. This research study presents the production of soybean oil biodiesel using synthesized guinea fowl eggshell catalyst (renewable catalyst). The catalyst preparation involves calcination at 850 °C for 3 hours in a muffle furnace. It was characterized using X-Ray Flourescence (XRF) and Scanning Electron Microscopy (SEM). Biodiesel was produced using 3-8 wt % of calcined catalyst within a time range of 1-2 hour, methanol/oil ratio of 0.25-0.5 w/w%. The highest biodiesel yield was 87.6% at optimum conditions of 8 wt%, 1.5 hours and 0.25 w/w% for catalyst amount, reaction time and methanol/oil ratio respectively. The biodiesel produced validates the successful synthesis of the guinea fowl eggshell into CaO. Biodiesel was then characterized to determine the acid value, flash point, cetane number, specific gravity, density, iodine value and kinematic viscosity. The characterization result of the biodiesel synthesized by using the guinea fowl eggshell catalyst produced showed that the biodiesel produced compares favorably with ASTMD standards.

Deforestation remains a serious concern for Africa's economic development and global climatic stability. This paper analyzed the effect of exposure to climate-related hazards on tree planting among smallholder farmers in nine selected African countries. The data were from baseline surveys which were conducted by the CGIAR's research programme on Climate Change, Agriculture and Food Security (CCAFS). The included countries were Burkina Faso, Ethiopia, Ghana, Kenya, Mali, Niger, Senegal, Tanzania and Uganda. Data were analyzed with Endogenous Switching regression considering the endogeneity potentials of climate-hazard exposure. The results showed that Uganda and Ethiopia had the highest average numbers of tree planting with 1.082 and 1.000 respectively, while Senegal (89.86%), Kenya (87.77%), Burkina Faso (82.86%) and Ethiopia (82.86%) had the highest exposure to climate-related hazards. Endogenous Switching regression results showed that climate hazard exposure was truly endogenous going by statistical significance of the Wald Chi Square test (p<0.05) and it was significantly influenced by female household headship, perception of more droughts, floods and low ground water. The number of tree that were planted increased significantly (p<0.05) with climate hazard exposure, degraded land areas, asset indices and residence in East Africa, while it reduced with female household headship. In addition, Average Treatment Effect (ATE) result indicated that an average household will plant 0.745 trees more when it had been previously exposed to climate shocks while Average Treatment Effect on the Treated (ATET) revealed that an average household that was exposed to climate hazards would plant 0.54 more trees than it would if it had not been exposed to hazards. It was concluded that many farmers had been affected by climate-related shocks and efforts to safeguard future climate through tree planting should be gender sensitive and concentrated among previously affected farmers.

Mobile phone users both for voice and data have increased tremendously in the last decade thereby making it necessary for service providers in the telecommunication industry maintain quality of service as much as possible. The huge complaint from indoor mobile users concerning signal coverage and capacity has made it a necessity to conduct this research. The aim of this research is to minimize interference among indoor phone subscribers in long term evolution (LTE) based heterogeneous networks using fast frequency reuse technique. Femtocells are deployed in varying number within the macrocell coverage area. For communication between femto and macro users within the network, a fast frequency response technique was proposed and parameters such as path loss, SINR and channel capacities were determined to ascertain the level of performance of the system when compared with a situation with random and unplanned deployment. Results show that a high SINR results when the bit error rate is low, this consequently improves communication and throughput in the network. The high values of throughputs for edge macro-femto users compared to inner edge-macro users are due to distance of macro and femto users from the macrocell. As femtocells increase for edge macro-femto users within the coverage area, throughputs reduced gradually

The rapid integrations of wireless controls in mechatronics, the broadening applications of wireless radio communications in aviation, and the exponential increase in the growth of mobile phone users in the last decade have made it necessary to expand the capacity of GSM users and ultimately increase the system performance. It has also become imperative for service providers to ensure adequate coverage is provided for all mobile users in areas with poor or no service. Even though many solutions such as distributed antenna system, relays, macrocells, and picocells were developed but they could not proffer the needed solution to indoor users. In this perspective, researchers were of the opinion that femtocells have a gifted technology to enhance indoor coverage because of properties such as short power, short coverage area, reduced distance between device and user and being a plug and play device. It was however discovered that research findings on large deployment of femtocells does not corroborate when a handful is deployed. This study therefore examines the influence of femtocells network on a small size indoor environment using ITU-R and WINNER II path loss models. To accomplish this, femtocells were modeled in six apartments of a building and parameters such as path loss, received power and signal to interference plus noise ratio were determined to ascertain the performance of a particular femtocell under the influence of co-tier interference. Results show that the ITU-R model was found to experience lower path losses which produced higher received powers than WINNER II (-57.0445dBm on the average).

The security and reliability of supply is often affected due to fault occurrence in electrical power Distribution Networks (DN). In the conventional DN, faults location takes more than the expected time, which results in economic losses to power utility companies as well as consumers. However, the advent of Intelligent Electronic Devices (IEDs) and recent advances in Information and Communication Technology (ICT) has made DN better, safer and smarter. In this paper, we present the outcome of simulation experiments carried out to locate faults in a DN. The IEEE 13 Node Test Feeder was simulated in SIMULINK with different fault conditions and the fault data acquired were utilized to develop an ANN classification model. The outcome of the experiments shows that the ANN based classification model is effective in locating faults on distribution lines with satisfactory performances.

The aim of this paper is to study the effect of welding current on the microstructure and the mechanical properties. Material characterizations were conducted on a 6 mm thick plates of type-304 austenite stainless steel, welded by TIG welding process at two different welding currents of 150 A (Sample F3) and 170 A (Sample F4). The tensile strength and the elongation obtained from sample F4 weld were approximately 584 MPa and 19.3 %; which were higher than sample F3 weld. The average micro hardness value of sample F4 weld was found to be 235.7 HV, while that of sample F3 weld was 233.4 HV respectively. Homogenous distribution of iron (Fe), chromium (Cr) and nickel (Ni) were observed at the welded joint of the two samples. The EDS analysis revealed that Fe, Cr, and Ni made up the composition formed at the weld zone. The optimum welding current of 170 A for TIG welding of type-304 austenite stainless steel can be recommended for high-tech industrial applications.

The principle of design by analysis was adopted for the design of this project. The methodology used was to scrutinize the common critical defects of conventional hammer mills and proffer possible solutions. The foremost components of the new blender-hammer mill were enumerated. The initial tests carried out on the new blender- hammer mill revealed that the mill is capable of performing same function that industrial huge hammer mills and the conventional hammer mills can perform in production of course, medium and fine particles.The results obtained after testing, showed that the crushing efficiency was between 83% to 96%, for dry maize and wheat respectively, which is quite satisfactory. Production of fine grains was achieved but coarse, medium and fine particles were still produced for further re-run for finer particle.

Few problems that have been identified with most of the existing developed blending and hammering machines/mills was strengthening on to achieved better performance. The aim of this project is to develop a blender-hammer crushing machine suitable for domestic and laboratory use for production of fine paste and coarse aggregates. The design was based on elimination of metal to metal contact, contamination of grinded material and excessive vibration. The blender-hammer mill consists of the following components; inlet hopper, grinding chamber, a combined crushing hammer blades vertically set and blending blade that are horizontally fixed. The mill was constructed from locally sourced martensitic stainless steel 420 series. A sieve was introduced beneath the hammer chamber to sieve the ground mass. The main shaft was mounted on two sealed ball bearings, and it rotates at speed of 2880 rpm transmitted by two 'B'V belt driven from a 3.75-kilowatt electric motor. The results showed that better efficiency for both dry corn and cassava. We conclude that a blender hammer machine developed is capable of grinding grains legumes, dry cassava, and yams into fine and coarse aggregates.

This research examined various factors that affect successful FDM-type 3D printing. Specifically diameters of the nozzles, extrusion width, and layer thickness were varied to create several print patterns and fills. These print patterns were tested for appearance/surface finish, strength, speed and stiffness of composite materials and then the best print parameters and methodologies were recorded. The solid interior pattern fill showed the highest volume fill available, representing fewer voids and thus better strengths and more durable parts. The solid interior pattern fill also had the best surface finish for all types of fill. Also, printing with small layer thickness produced stronger prints albeit at higher build times.

Today, agricultural waste is one of the most common resources in Nigeria that could solve environmental, fuel and energy issues. However, it has some limitations such as low bulk densities, loose and irregular sizes, handling and storage problems, low energy density, reduced fixed carbon, low calorific value, high volatile matter and high moisture content etc. making it difficult to be utilized for fuel. One of the viable and promising technologies to upgrade the properties of raw biomass is through torrefaction technique which is capable of upgrading the combustion and fuel characteristics of biomass, demonstrated from behaviours that are similar to coal during combustion. During this process, about 70% of the initial biomass weight and about 90% of the original biomass energy is obtained as torrefied biomass while the remaining 30% biomass weight and 10% biomass energy is given off. In addition, the presence of moisture content in raw biomass that could aid biological degradation is reduced (< 3% w.b.) while combustion efficiency is being enhanced through upgraded fixed carbon and calorific value (15-25% wt) and reduced volatiles. These upgraded properties makes torrefied Nigerian biomass suitable to be used independently or co-fired in power plants and as an upgraded feedstock for domestic and industrial applications in a developing country like Nigeria. Unfortunately, there is scarce research materials on biomass torrefaction in Nigeria which could be attributed to the cost of acquiring torrefaction plant and other resources for torrefaction characterization which are on the high side. This paper therefore explores and reviews the property upgrades of raw biomass through torrefaction technique. The challenges of biomass energy in Nigeria, torrefaction effects on some Nigerian biomass, equipment used for the analysis of torrefied samples, alongside the torrefaction properties, combustibility indices and their products were examined. The review study concluded that torrefaction technology is a promising technique in Nigeria which is capable of improving and upgrading the quality, energy value and other properties of raw Nigerian biomass and could at the same time serve as an alternative source of energy asides hydropower energy if embraced by the concerned bodies.

Several studies have been carried out to measure the concentrations of dimethylsulphide (DMS) and dimethylsulphoniopropionate (DMSP) in coastal and open marine ecosystems. The present study attempted the fabrication of a cost-effective, highly sensitive and portable detection system based on vapour generation and chemiluminescence for a pilot assessment and determination of DMS and DMSP concentrations in tropical Atlantic seawater samples. The Sultan Beach and Badagry parts of the Atlantic Ocean were chosen as designated locations for this study. Vapour generation chemiluminescence (VG-CL) detection system is a device that can measure the concentration (nM) of DMS and DMSP by allowing DMS vapour which in turn reacts with ozone to produce chemiluminescence which can be detected by a photomultiplier (PMT). The mean concentrations of DMS and DMSP in the surface seawater at the sampling location were 5.80±0.71 to 19.40±0.57 nM and 11.00±0.42 to 34.70±1.13 nM, respectively. The average minimum and maximum concentrations of DMS and DMSP across the location were between 0 and 40.91 nM, respectively. This study serves as a baseline measurement of DMS concentrations in the tropical Atlantic Ocean (Lagos).

Water borne diseases have continued to linger and has remained a major challenge facing most developing nations today. This has been caused mainly by lack of access to clean water. The rapid industrialization has led to the discharge of effluents loaded with pollutants into our water bodies that have greatly affected humans, aquatic life and the environment. This work looks into the possibility of improving the quality water through the elimination of (i) inherent contaminants in water using filters made from cheap locally available red clay and biomass (300 microns sawdust) materials and (ii) chemical treatment of industrial and domestic effluents which in itself is a source of environmental pollution. The sawdust-clay materials were first thoroughly dry mixed in four different weight ratios, 6/80 (sample A), 5/80 (sample B) 4/80 (sample C) and 2/80 (sample D) before water was then added gradually and mixed until the clay clumped together completely, softened and workable. It was then wedged by pressing firmly in order to remove bubbles from the inside of the clay and molded into cup--like shape. It was first sun dried then oven dried at 110 °C and then fired in a Muffle furnace at 850 °C to burnout the sawdust biomass and thus create fine pores within the clay matrix. Performance of the sawdust-clay filters for the purification of waste water obtained from two different sources, industrial and kitchen effluents, was investigated. Results obtained from the study showed that the four filters (A, B, C and D) proved to be moderately effective for the treatment of the two effluents. All the filters reduced the total dissolved solids (TDS) to 120 and 110 mg/L of the industrial and kitchen waste water respectively, to acceptable levels which is less than 500mg/L, set by the World Health Organization (WHO). Conductivity values obtained after the treatment of the water samples were lower than the 1000 µs/cm limit set by WHO. And with the exception of filter D, others greatly reduced the turbidity of water samples as values less than 5 NTU as set by WHO were obtained. The pH values or acidity reduced for the industrial waste water from 4.5 to 7.02 and for kitchen waste water from 5.1 to 7.02 which met the specification set by WHO. Some of the heavy metals detected in the water samples were effectively reduced to acceptable levels. The filtration rates were 140, 100, 50 and 20 ml/min for filters B, A, C and D respectively. The rates rapidly reduced to about 2.7, 1.7, 1.0 and 0.7 ml/min for A, B, C and D respectively after 30 minutes of filtration. This implies that the filters were effective and should thus be developed for industrial and domestic waste water treatment applications.

There is still an increase in the demand for engineering innovations in designing cassava peeling attrition machines which will limit drudgery which its operators are being subject to. However, one major factor that has limited all existing designs is the fact that cassava tubers have irregular geometries. Hence, the emphases of this thesis is to design based on modifications, fabricate test and performance evaluation of a cassava tuber peeling machine using standard available materials by basically inculcating two contra-rotating shafts with brushes as deflectable knife edges and an auger that is inclined at an angle thus being powered by an electric motor and gravitational energy of the earth. The components of this machine include a main frame, feeding hopper, cylindrical peeling chamber, auger conveyor, belt and pulley transmission system, chain and sprocket transmission system, waste outlet, manual handle bearings and 1hp electric motor. By operation, cassava tubers are introduced into the feeding hopper which is then collected by the auger into the extracting compartment at an angle of 10 degrees, the auger conveyor which is well fitted inside the peeling chamber then translates the cassava tubers, and then presses the cassava tubers against the brushes. Each brush acts as a knife edge and also deflects to create an opening to accommodate the variable irregular cross sections along the length of any cassava tuber. The minimum and maximum mass of cassava tubers that are loaded into the peeling chamber from the introductory sector in different time intervals are 4.5kg and 5.0kg respectively. The Throughput Capacity of the machine is 47.9kg/h. The minimum and maximum force exerted per unit length of cassava tuber by each brush is 1.02Nmm-1 and 1.85Nmm-1 respectively. The machine was evaluated at stepwise speed of 50rpm from 50rpm to 250rpm. The minimum moisture content of each cassava tuber was 45% and a maximum of 70%. The maximum peeling efficiency was obtained at the minimum speed of 50rpm and a maximum moisture content of 70%.

The study was conducted to investigate the causes, effects and controls of Boiler rupture in Egbin Steam. Thermal power plant, Lagos State. Three classes of boiler rupture were investigated for twenty-nine cases of boiler rupture. The cases were grouped into classes through stratified sampling technique. Analysis of Variance (ANOVA) at 95% level of significance was used to test the two research questions set for the study. The results of the study indicate that the various classes of boiler rupture are not equally significant, one class more prevalent and responsible for incessant forced power outages than the others. With respect to tube failure, the findings indicate that each of the various factors responsible is uniformly significant. Recommendations for proper maintenance planning, in order to prevent boiler rupture which could lead to forced power outage, were made. The effects of boiler rupture include reduction in load factor, plant utilization factor, profit, plant generation factor, plant efficiency and increase in down time, operation and maintenance costs.

Early detection of diseases is key to better disease management and higher survival rates. It aims at discovering conditions that have already produced biochemical changes in body fluids, but have not yet reached a stage of apparent physical symptoms or medical emergency. Therefore, early disease detection relies majorly on biochemical testing of biological fluids such as serum, in the body. The laboratories for these tests require biochemical-based instrumentations that are bulky and not commonly available especially in developing countries. Moreover, the tests are expensive and require trained personnel to conduct and interpret results. On the other hand, Lab-on-a-Chip (LOC) biosensors have a potential to miniaturize the entire biochemical/laboratory methods of diagnostics into versatile, inexpensive and portable devices with great potential for low-cost Point-of-Care (POC) applications. They are capable of providing accurate and precise information on the measured health indices for sub-clinical level of diseases. Nanotechnology-inspired biosensors have further advantages of low limit of detection (required for early diagnosis), real-time analysis and lesser sample volume requirement. Of all other nanomaterials, graphene is said to be the most promising, suitable for biosensing due to its biocompatibility and consistent signal amplification even under the conditions of harsh ionic solutions found in the human body. This paper reviews the potentials, fundamental concepts and related works in using Graphene-based Field Effect Transistors (GFETs) as biosensors for early disease diagnosis. This paper also highlights a low-cost patterning mechanism for preparing SiO2/Si substrate for metal deposition (of the source and drain electrodes of FETs).

In this review paper the use of agro waste as a sustainable source for steel reinforcing steel was investigated. Agro waste is said to have certain amount of carbon which can be useful for steel reinforcement, as stated by different authors the carbon derived from agro waste is said to be of high quality. From literature it was observed that there is an increase in demand of agricultural produce which mean automatic increase in agricultural waste and this threat on humans, plants and the environment, this alone shows that agro waste is sustainable as it is currently been underutilized in the steel or iron making industry. In this review different agro waste such as macadamia nut shell, potato peel, husk from cereal, rice husk etc, and it was observed that macadamia nut shell has the highest carbon content which is about 92%. Agro waste is a sustainable source of obtaining carbon and should considered by steel producing companies as the carbon content is high and its environmentally friendly.

Banking sectors have perpetual queues owing to the significance of the services they render to humanity and this poses a merging challenge of queue management in the execution their jobs and in the effective delivery of services to their customers. The study focuses on the role of queuing theory in the banking sectors thus far from pedigree of queuing theory till date. This study used the historical approach to juxtapose the likelihood of the impact of queuing in the various activities in the banking as seen in the regular applications to established areas of telecommunications systems and engineering. The outcome of this review espouses that a few approaches have been applied to sort the problems encountered in the banking sectors for needful improvement. Some of these approaches are ANN (Artificial Neural Network), BPR (Business Process Reengineering) M/M/1, M/G/1 and the Erlang B&C formulas for the management of excessive bank reserves and customer queues in terms of waiting times and economic cost. These approaches have been able to improve the performance of the banking sector to an extent, however there is still a couple of limitation regarded as external factors that varies from one banking system to another and lots of works are needed to further combat the problems faced by the banking sectors.

The use of metals in this present age has increased greatly, the metals that were used in the past in different industries such as the automobile or construction industry were metals that are heavy and expensive but there's been a rapid shift from that to lightweight metals that are less expensive and also have super strength due to the increased material properties such as ductility, hardness, wear resistance etc. Increasing the properties of metal is achievable by subjecting it to heat treatment, which helps in obtaining desirable properties. Quenching is known to be rapid cooling process for heated metals and it has significant effects on mechanical property, phase crystals location and structural analysis. This overview revealed the significant index control in heat treatment of a metal.

A concern over the toxicity of chemicals used during the activation stage in the preparation of activated carbon is beginning to gain attention. The study therefore looked into the possibility of using bio-activators (lemon juice and potash leached from the peel of unripe plantain) as activating chemicals, for environmentally friendly activated carbon. Coconut shell and the peel from unripe plantain were used as feedstock and pyrolyzed at 400 and 450 °c. An impregnation ratio of 0.25:1 was used while laboratory grade potassium hydroxide was used as a base activating agent as a control setup. Characterization of the activated carbon was carried out using parameters like bulk density and yield which were obtained using standard procedures. Results showed that activating carbon using bio-activators as activating agents had very good characteristics when compared with the control. Bio-activators are therefore recommended for the production of bio based activated carbon especially in the fields of medicine, food and pharmaceuticals. The effect of carbonization temperature on adsorption efficiency and pore structure were investigated using methylene blue as adsorbate and SEM respectively

Interest in glycerol oxidation to more useful products has risen significantly over the years. This has led to the development of several catalysts some of which are scarce, uneconomical and environmentally unfriendly. In this research, two catalysts prepared from red earth - 'A1' (calcined at 500°c) and 'A2' (calcined at 500°c and dealuminated) were characterized using x-ray fluorescence (XRF) and used to oxidize glycerol with O2 molecules for 240 mins. The XRF results showed that Al₂O₃ (31.3%), SiO₂ (47.9%) and Fe₂O₃ (16.05%) were the predominant components in 'A1' while 'A2' showed a marked significant difference in Al₂O₃ (19.4%), SiO₂ (72.1 %) and Fe₂O₃ (0 %). The selectivities of the oxidation products with A1 were 18.8 % glyceric acid (GLA), 13.1 % lactic acid (LCA), 1.66 % oxalic acid (OXA) and 1.24 % formic acid (FMA), while for A2 they were (20.4%) GLA and (17%) LCA. 88.1% glycerol was converted but selectivity towards any of the products was low.

Energy efficiency, which is a key factor of sustainable building design is very beneficial to building occupants. This has made the focus on sustainability in the design, to be highly desirable. Studies show that two third of the energy used in existing residential buildings in Nigeria is generated via electricity, however; due to epileptic power supply, high cost of energy and high carbon emission, there is a need to minimize energy demand in the facility. This research evaluated sustainable design strategies and their effects on energy efficiency in warm humid climate of Nigeria. The climate, building envelope, heating, ventilation and air conditioning and lighting systems constitute are the main factors responsible for energy intake of a building. The research was based on case study of Covenant University Health Centre and data was collected through visual survey. The case study revealed that the building, at the time of construction did not consider sustainable design strategies in terms of materials of the building envelope, wall and window shading as well as natural means of cooling. Only lighting was considered.

Several negative environmental issues are attributed to the activities of the construction industry (CI) globally with South Africa as no exception. Hence, the introduction of sustainability concepts in other to address these challenges which continually threaten the health and existence of both the human and natural environment. Green building (GB) as a sustainable concept aims to address the social and economic concerns and not only the environmental issues in the built environment. The paper, therefore, evaluates the beneficial factors and ways of promoting the implementation of GB projects in South Africa. The study employs a structured questionnaire survey as an instrument for data collection. The study gathered data from construction professionals (architects, civil engineers, quantity surveyors, project managers, construction managers, and construction project managers) who are sustainability proponents. A quantitative approach to data analysis was utilised using percentage, standard deviation, and mean item score. From the data analysed, the results revealed improved indoor air quality, ecosystem protection, increased energy efficiency, enhanced health and well-being of occupants, and minimised CO₂ emissions as the top five benefits of GB projects implementation. Availability of more financing options, improved market for green products/materials, education and training on GB technologies, provision of economic incentives, and affordability of GB materials are identified as the top drivers of GB projects implementation. The findings from this study will help create awareness and encourage the adoption and implementation of GB projects which in turn has the potential to combat the severe environmental challenges caused by the activities of the CI.

Engineering is increasingly becoming a more popular career for women globally. This study aims at examining the performances of female students in comparison to their male counterparts. This is then used to determine if there is any correlation in their performances. The sample population for this research is the engineering students in Covenant University, a leading University in Nigeria. The performance of the graduating students in this school over 11 years, from 2006 to 2017, was analysed and studied. The research suggests that more percentage of female students now graduate with first class and the percentage of female students graduating with third class between these periods has reduced to almost nothing over years. Thus, it is recommended that more women should be encouraged to enrol in engineering courses, as they tend to thrive in courses such as Electrical and Electronics Engineering and Mechanical Engineering.

Electricity is an integral part of every society for which demand is growing continuously, whereas the production is still based on limited sources of energy derived mainly from steam and gas turbines, the turbomachinery. This paper presents an overview for preliminary study on the optimization of the design of the steam turbine. This was done with a special focus on the last stage low pressure turbine blades, for the reason that the design parameters of this component exhibit influence on the efficiency of power generation from the steam turbine electric power generating system. For supporting the study, a practical overview of the Egbin thermal power station, Nigeria, was included in the study with the parameters from the last stage low pressure turbine blade for this energy generation installation. By these, suggestions that could be undertaken for improving efficiency of the steam power plant for enhancing sustainability of electric power generation were also detailed in the paper.

This study was carried out to design and construct a cost-effective and efficient solar-powered phototherapy device which can be implemented in areas where there are inadequate electricity and rural environment. Neonatal jaundice is the yellowish condition due to high-level bilirubin in a new born baby. This condition must be treated if the bilirubin level above 12 mg/dL. One of the common treatments is by using red and blue light phototherapy to convert bilirubin become more soluble in the water then easily excreted from the body. A microcontroller was used to regulate the radiation of light in the device and make it safe for the treatment of jaundice in a new baby. The device is powered by solar energy generated from the 24-volt monocrystalline solar panel, for charging deep cycle batteries via a charge controller. The wavelength of light is 460-490 nm with a minimum intensity of 30 μW/cm2. In this study, the phototherapy device is designed and tested. The red and blue light source consisted of thirty-six (36) high power Light emitting diode LED. Heat sink and fan are employed for the LED package cooling system. Solar power meter and spectrometer are used to analyze the intensity and wavelength produced by the LED.

Glazing materials have been found to greatly influence the performance of trombe wall systems. this is due to its role in determining the quantity of thermal energy that reaches the massive wall. in this article, a multi-criteria decision-making analysis for proper glazing selection for trombe wall system was considered, the location of interest is johannesburg metropolis. four different glazing types and four criteria were considered using the entropy method for weight determination. the four criteria considered were the solar heat gain coefficient (shgc), the u-value, visible transmittance and cost respectively. the result showed that the u-value is of utmost importance vis-a-vis other performance criteria for the glazing material. decreasing order of weights assigned was as follows; 71.2% weight factor for the u-value, 16% weight factor to cost, 10.2% weight factor to shgc and 2.6% weight factor to the visible transmittance respectively.

Automation technology is a new area of technology that requires proper selection of variables to minimize cost and maximize profit. This paper is aim at developing a mathematical model that will be able to solve all automation cost estimating systems (ACES), be it full automation, partial automation, manufacturing automation or service automation as well as fixed, flexible or programmable automation. Extensive research has gone into cost modeling over the years and many commercial, as well as free software solutions, have been widely exploited to proffer solutions to cost modeling especially in ACES. Hence, a lasting solution to the problem of ACES, its implementation, and application in automated manufacturing and process industries is demonstrated in this paper.

The AA8011 reinforced with 5 to 20 weight percent of zirconium diboride (ZrB₂) were developed via stir casting route. In this current research work, characterization evaluation was conducted on the AA8011 alloy and its composites with the varying composition to investigate the physical and mechanical properties. The results of the mechanical properties obtained revealed an enhanced hardness and strengthening mechanism propagation of the composite in comparison to the base alloy AA8011. The experimental studies show that the addition of ceramic particles into the molten metal alloy resulted in improved properties. Also, an increase in the percentage composition of the particles leads to an increase in the strength value of the composite. Generally, the improvement in the hardening mechanical behavior of the composites can be attributed to the intrinsic properties of the incorporated particulates.

Glazing are functional components of Trombe walls, they determine to a great extent the performance of the system. selection of optimal glazing for trombe wall application was considered in this article and the TOPSIS methodology was employed. TOPSIS is a multi-criteria decision-making algorithm which means a technique for order preference by similarity to ideal solution. considered in this article were four different glazing types and four criteria. the single glazing was the closest to the ideal solution followed by the double pane glazing with low emissivity coating, double pane glazing with high emissivity coating and the triple pane glazing respectively

Mild steel is the most common type of metal used in large industries due to its acceptable material properties and low cost. However, a growing concern of its use has been limited as a result of its low resistance to corrosion especially in acidic and alkaline environments. The use of corrosion inhibitors has been encouraged by various researchers as a means slow down the corrosion rate and thus reduce monetary losses to industrial vessels, surfaces and equipment. This paper presents the types of inhibitors employed by different researchers on various mediums. It also seek to consider the limitation processes caused by some factors such as temperature of the media and concentration of the inhibitors and the media. Although the use of green inhibitors has been greatly encouraged due to its low cost but the combination of it with other kinds of inhibitors can prove to boost its effectiveness in corrosion inhibition process. Other organic materials such as animal discharge, and biomaterial should also be considered in future research works. These will further provide more literature to corrosion inhibition of mild steel which in essence promotes the life span of the metal.

The universal water scarceness and the extensive ordeals with energy cost in conjunction with the undesirable ecological effects have advanced the improvement of novel osmotically driven membrane processes. Membrane processes which are osmotically driven are developing type of membrane separation procedures that apply concentrated brines to separate liquid streams. They are adaptable in various applications; hence, allow them to be an attractive substitute for drug release, wastewater treatment and the production and recovery of energy. Although, internal concentration polarization (ICP) occurs in membrane practises which are osmotically driven as a consequence of hindered diffusion of solute in a porous stratum, their interest has even increased. Here we review two natural membrane processes that are osmotically driven; Forward osmosis (FO) and Pressure retarded osmosis (PRO). Thus, the major points are as follows: 1) it was highlighted in this review, that the major developments in FO process, important for the process efficiency is to choose a suitable membrane and draw solution. 2) The recent evaluation, understanding and optimizing the activities of fouling throughout the osmotic dilution of seawater employing FO was discussed. 3) Recent advancements of FO in the application of food processing was reviewed. 4) It was highlighted that the main concept of PRO for power generation is the energy of mixing that offers great assessment of the non-expansion work which could be generated from mixing; nonetheless, the development of effective membranes with appropriate arrangement and performance is needed for the advancement of PRO process for power generation. 5) One major challenge of osmotically driven membrane processes, most recent developments and model development to predict their performances were discussed.

This paper accords the likelihood of applying Donnan and Steric Partitioning Pore Model (DSPM) together with extended Nernst-Planck model to elucidate the capacity of charge and Donnan exclusion mechanisms in removing ions from simulated wastewater in Nano-Pro-3012 membrane filtration process. The extended Nernst-Planck model reports the transportation of cations across Nano-Pro-3012 with respect to electrical potential gradient, movement of solutes and pressure difference through the membrane. The working principle of these two equations is dependent on the adsorption of the charged surface, diffusion and convective transport. This principle was established with a software called Comsol multi-physic 4.3b to explain the capacity of charge and Donnan exclusion mechanism of Nano-Pro-3012. The extended Nernst-Planck model and the Darcy law model were applied to evaluate the physical interrelationship amidst NanoPro-3012 and ionic solutions with the aim of having a good understanding of the transport and rejection working operation of the ions. The principle of these equations was first used to envisage the capability of Nano-Pro-3012. The data obtained were validated with the laboratory data. There was an establishment that movement of solutes across the membrane bring about diffusion transport. The total flux in solution increases due to the working operation of the diffusion which in turns reduces the electrical potential, as a result, reduces the flux in the membrane. Ions smaller than pore sizes are rejected and the theoretical data is in conformity with the experimental data.

Failures in aerospace structural components have catastrophic consequences, which results in loss of lives and of the aircraft. Failure occurs when a component or structure is no longer able to withstand the stresses imposed on it during operation. Application requirements of aerospace components involves high durability in order to withstand high temperature and pressure environments (such as leaving the earth's atmosphere or exposure to burning rocket fuel) and must be light weight for easy lifting and fuel efficiency for rockets. Compressor blades in aero-engines are designed for many distinct functions and are required to withstand high temperatures imposed on them by high rotational speed in the form of large centrifugal load and aerodynamic force applied as a function of pressure rise through each stage of the compressor. The paper reviews the advancement in the application of alloys and composites in the manufacture of aircraft component.

The present study investigated the degradation of total petroleum hydrocarbons (TPH) in crude oil polluted water using sodium persulphate as a chemical oxidant. Laboratory-scale contaminations of water and degradation experiments using 0.1 M oxidant were carried out with contact time ranging from 1 to 15 days. The TPH extraction was carried out and analyzed using gas chromatography flame ionization detector (GC-FID) (Agilent 7890A). 72% of ETPH was degraded within 15 days from an initial concentration of ∼137 mg/L. Results indicated 99% efficiency in TPH degradation achieved within the first 10 days after initial contamination. Remediation technique on laboratory- and field-scale is promising and could potentially address major oil pollution contamination issues.

Improving energy efficiency requires detailed information on energy utilization. Many a times, institutional buildings across developing countries are not energy efficient. Thus, they require quantitative energy consumption audit information. This study outlines daily, weekly and annually projected energy consumption in an academic building within Nigeria. Measurements of the energy utilizations of the building were in accordance to ASHRAE Standard 22, ASHRAE/IES Standard 100-2015 and BCA Health Check report guidelines. Results showed that HVAC appliances and electrical motors driven gadgets consumed 36% and 61.9% of the total energy supplied. In conclusion, improving energy efficiency of similar facilities requires energy conservation practice in terms operating motors and other HVAC devices off idle-time and non-occupancy period respectively.

The way shopping malls have sprawled every nook and cranny particularly in the developing economy is evident from major cities to even sub-urban areas. The expansion evident in the various locations of these shopping malls can be attributed to its patronage. Earlier researchers have linked the patronage of these malls to influences resulting from location, gender, image, type of shoppers amongst other. Even though studies on facilities and how it influences patronage are evident particularly in the developed economies such work also studied other factors thereby not giving a detailed finding on the linkage between facilities provided in such malls and the level of patronage from shoppers. This present study thereby focuses on influence of facilities provided on patronage of the five (5) identified shopping malls in Ibadan, Oyo State Nigeria. The study being a cross-sectional research survey entailed the distribution of questionnaires to 143, 126, 127, 145 and 126 shoppers of Cocoa Mall; Heritage Mall; Jericho Mall; Palms Mall and Ventura Mall, respectively all located in the study area, Ibadan. A cumulative response rate of 80.3% was attained. Data collected was analysed using descriptive statistics of weighted mean and substantiated with factor analysis. It was revealed that most identified facilities in the malls have a great influence on patronage of the malls. However, in order to avoid superfluity of investment, investors could commence provision of Eatery / Food court (Co-V1, 0.72) as recreation facility; Kids play center (Co-V1, 0.79) as children's facility; Toilet/Restroom (Co-V1, 0.84) as service facility; POS (Co-V1, 0.91) as banking facility and free medical checkup (CoV1, 0.91) as health facility as these have most remarkable influence on patronage of the malls. The researchers hereby advocated that investors can be guided in the provision of the relevant facilities to prevent superfluity while the keen sustenance of these specific facilities can sustain patronage of the various malls in the study area.

An important component of environmental sustainability is how we can continue improving human welfare within the limits of the earth's natural resources. With recent research showing that carbondioxide levels in the air are at their highest in 650, 000 years and thus an alarming depletion of the ozone layer, the challenge currently facing many countries is how to respond to the issue of climate change. Steel, reinforced concrete and timber are the most commonly used structural materials worldwide. However, carbondioxide emissions from steel and cement production have been found to be the first and second largest sources of industrial CO₂ emissions worldwide and this has prompted the inclination towards timber as a structural material. Timber is decomposable or biodegradable as well as renewable and its production does not require the use of high energy fossil fuels as in the production of some other building materials such as steel or even brick. Nigeria is blessed with several timber species in different wood classes but despite the environmentally sustainable and obvious advantages of timber, it is being grossly underutilized as a structural material in Nigeria because there is limited information on the reliability of timber considering the wide property variability between and even within, timber species. This paper addresses the need for reliability analysis of various Nigerian timber species with a view to determining and establishing their structural strength to encourage the use of the Nigerian Timber as a structural material. The need to revise the Nigerian Code of Practice for the structural design of Timber is also emphasized in this paper.

The quick exhausting of traditional energy sources and the present consistently expanding energy request with regards to ecological issues have supported concentrated research on solar energy innovation. Apprehending most extreme energy from the sun by utilizing solar PV technology is impenetrable. A few features that influence the solar energy yield of this technology comprise the material of the photovoltaic, solar irradiances topographical area, the orientation of the panel, the angle of sun and surrounding climate. This present work reviews the ideologies and contrivances of solar PV tracking systems to decide the greatest solar panel tilt-angle, both isotopic and ant isotopic solar models and uses of numerous procedures for outlining solar panel tilt- angle by means of dissimilar optimization techniques. The work displays that sun-tracking systems are quite expensive than the opposing fixed mounted variety. This is mostly due to having motor-powered and moving portions. More also, having all these moving and mechanical parts means that there will be some amount of regular inspection, adjustments or even replacements required which leads way to another disadvantage. For greatest energy harvest, the optimum tilt angle for solar PV systems must be resolved definitely for every territory as it is basic for most extreme power generation by the system.

The mitigation of corrosion is a major problem for many industries all over the world as it is costly to maintain metals especially in all energy sectors. There are different methods been used such as painting, coating and galvanizing; but, all these solutions are relatively expensive and cause harmful effect to the environment. it is pertinent to develop and apply emerging technology that will yield high resistance to corrosion, as a way of controlling corrosion in order to reduce corrosion cost, lower the risk of failure, accidents and extend the useful lives of equipment and building. This foster the search of natural plants with green inhibitors which are eco-friendly and relatively inexpensive. This paper investigates the corrosion mechanism process and possible mitigation in steel application.

Heat treatment of gears are fundamental to efficient and reliable gear production because of its contribution to the overall cost of manufacturing. Different heat treatment techniques are targeted to improving hardness, ductility and strength to minimize material degradation or wear. However, several heat treatment methods had led to gear tooth distortion such as shrinkage of tooth thickness which eventually affects the contact angle. The study therefore focused on some selected heat treatment on gears and their effects on gear applications. from the reviewed heat treatment techniques, distortion is a common occurrence that result to gear fatigue. Also, it was noted that most times, the medium for quenching and most importantly, variation in the concentration affects the gear accuracy. Thus, local fracture and material loss ensue. Nevertheless, the study further suggested the use of empirical model and simulation approach for stress prediction.

Medicinal plant research is a highly diversified topic of interest owing to applications of their phytoconstituents in drug discovery, human dietary intake, corrosion inhibition, material science research among others. The study revealed the phytochemical composition and proximate determination of Pentaclethra macrophylla benth (African oil bean) seed. The dried seeds of Pentaclethra macrophylla benth were pulverized into fine powder and a portion of it was extracted with n-hexane. The result of the phytochemical screening of the extract from Pentaclethra macrophylla showed that the oil seeds contained terpenoids, cardiac glycosides and saponin while steroids, alkaloids, flavonoids, tannins, phlabotannins and anthraquinones were not detected. Proximate analysis indicated low moisture content (1.895 %), while other parameter determined include ash (2.033%), crude fibre (17.227%), acid value (8.182), iodine value (101.235), peroxide value (20.06), and free fatty acid (4.091). This extract is a candidate with potential for further study regarding unveiling of their mechanical properties for technological advances.

Biogas is produced from anaerobic digestion of biodegradable solid wastes in bio-digesters. Agricultural residues, comprising of animal manure and waste biomass, can constitute unfavourable environmental issues if not properly disposed. Studies aimed at converting these residues to energy need serious attention due to fast depleting rate of fossil fuel and its environmental hazard. Four cylindrical biogas digesters (A, B, C and D) of 0.052m³ capacity each were constructed and fed with cattle dung, sunflower leaves, pawpaw and potato peels at different percentage composition. The experimental set-up was left for a retention period of 40 days, after which biogas production stopped. Results revealed that the percentage Organic Dry Matter (%ODM) of cattle dung, sunflower leaves, pawpaw and potato peels were 94.91, 95.92, 97.75 and 96.60 respectively. The total volume and methane contents of biogas produced from digester a, b, c and d were 46.64, 45.80, 39.55 and 38.02 m³, and 71.82 %, 53.71 %, 66.80 % and 52.70 %, respectively. Analysis also revealed that digesters A had the highest Fresh Mass Biogas Yield (FMBY), Organic Dry Matter Biogas Yield (ODMBY), Fresh Mass Methane Yield (FMMY), and Organic Dry Matter Methane Yield (ODMMY). The Higher Heating Values (HHV) of biogas obtained from digesters A, B, C and D were 6.931, 5.680, 6.679 and 5.549 kcal/kg, respectively.

This paper presents the results of a numerical synthesis and characterization of vibrations of low-pressure steam turbine last stage rotating blades. A Fluid Structure Interaction (FSI) study is carried out using ANSYS Fluent 18.1 and ANSYS Mechanical 18.1. Using a one way coupling between ANSYS Fluent and ANSYS Mechanical, it was possible to link the two systems and allow pressure force calculations from Fluent to be used for the blade excitation in ANSYS Mechanical. The result of simulation shows that the blade exhibits vibrations which are characterized by amplitude modulation. An approximation for the equation of motion along the axial, radial and tangential direction was uncovered and fit. The three approximations for the blade vibration show a good agreement with results from ANSYS Mechanical. The effect of liquid mass (droplets) in the flow in the blade vibration was also investigated numerically. It is shown that increase in liquid mass is directly correlated with increase in the amplitude of the vibrations but has no effect on the frequency of the vibrations.

Anaerobic co-digestion requires the digestion of two or more homogenous substrates to produce biogas. The superlative participated condition is when principal amount of most important substrate (example manure or sewage sludge) is combined and fermented with each other with lesser quantities of single, or a variety of additional substrate. The co-digestion of one or more substrates commonly improves the biogas output from anaerobic digesters owing to positive improvement brought about in the digestion medium and the furnishing of missing nutrients in one substrate by another. Anaerobic co-digestion of cow dung and jatropha cake for biogas production was carried out in the batch digester in the absence of oxygen at ambient temperature with different mixing ratios for 40 days. The result indicated that treatment with 75% jatropha 25% cow dung had the highest volume of biogas at the rate of 24.41% and treatment with 100% jatropha released has the highest percentage quality of biogas produced (methane) at the rate of 59.6%. Treatment with 50% cow dung 50% jatropha cake was found to be the appropriate mix ratio, since it was rank 2^nd in both qualitative and quantitative analytical point of view from the experiment performed.

The thermal performance of a heat exchanger can be enhanced by adding carbon nanostructured materials such as carbon nanotubes and graphene to the conventional working fluid. When nanomaterials are suspended in the working fluid, the fluid is known as Nanofluid. The enhancement in the thermal and rheological properties of the fluid is responsible for the augmentation in heat transfer performance. The influence of carbon nanomaterial on the thermophysical properties, heat transfer characteristics and flow properties are reviewed. The current trends on the utilization of carbon-based nanofluids in heat exchangers were reported. The study shows that carbon-based nanofluids have the potential to improve the performance of heat exchanger and reduce the cost of fabrication by reducing heat exchange area. The study identifies the scope for future study.

Tranquility is one of the healthy environment factors on the residential areas which elevate the standard of living of the people and their psychological well-being. On the contrary, when there is a high level of noise intrusion at home, it might deprive one of these benefits. This study measured the industrial noise intrusion level in the residential area with respect to distance. A total of 40 residences, with 8 each around 5 food and drug processing factory sites in three local government areas (Idemili North, Onitsha North, and South) of Anambra state, Nigeria were selected as study site locations. Benetech Model GM 1352 digital sound level meter was used for the measurement of environmental outdoor noise levels at a height of 1.5 m and 3 m from any reflecting surfaces. The distance between the factory sites and the residences assessed was calculated using the coordinates of the study site points obtained with A Garmin GPS 72H on the CDXzipdistance2WP function on Microsoft Office Excel. All measurements were carried out during the daytime between 6:00 am – 10:00 pm. Three categories of environmental outdoor samples of noise levels were obtained; off work-hour, and work hour which comprises of generator usage and the national grid connection hours. The computed L_Aeq noise intensity level obtained at the residences assessed showed that 12(30.0) and 28(70.0) of the residences assessed were quiet and moderately loud during national grid connection hours which was; quiet 32(80) and moderately loud 8(20) during off work-hours. It, however, translated to moderately loud 24(60.0) and very loud 16(40.0) during the engagement of the services of electricity generator. The Pearson correlation analysis showed that there was a strong negative correlation between the distances of the residences assessed from the factory sites and the noise level which were significant at p < 0.01 for values of r = -0.976 during generator use and 0.981 when compared with the national grid. This implies that the closer factory sites are on the residential area the higher the noise intrusion level which is not healthy.

The article aims at investigating the performance of diesel engine and emission properties of non-eatable oils methyl esters of J. Curcas L. and Spirulina Platensis microalgae based biodiesel in diesel engines (DE). Kirloskar Six cylinder diesel engine was the test engine used to ascertain the level of Break Power (BP) and BSFC and the Emissions of Carbon (IV) Oxide (CO2), Hydrocarbons (HC), Carbon monoxide (CO) and Nitrogen Dioxide (NOX). Different ratios of biodiesel were mixed with diesel fuels using 10.0 and 20.0 percent by volume of methyl esters with the diesel fuels for example AB10 (10% by vol. Biodiesel and 90% by vol. Diesel fuels), JB10, AB20 and JB20 respectively. However, the procedures of the experiment was in agreement with EN 14214 and ASTM D6751 procedures. The biodiesel fuel samples used decreases the brake power (BP) and increase brake-specific fuel consumption (BSFC) when compared to conventional oils. Results from emission indicates that the blended biodiesel reduces CO, CO2 and HC Emission and causes an increase in NOX emission. Since AB10 gives lesser emissions, it is a better option for diesel fuels in engines that are not modified to minimize exhaust releases in the environment.

This study analyzed the gravimetric and electrochemical effects of C₁₆H₁₃N₃O₃ (methyl-5-benzoyl-2-benzimidazole carbamate: Mebendazole) on mild steel corrosion in 0.5 M H₂SO₄, for gaining insights on correlation and significance of differences between the two corrosion-monitoring techniques. For the gravimetric method, weight loss of mild steel specimens immersed in different C₁₆H₁₃N₃O₃ concentrations mixed in the 0.5 M H₂SO₄ were obtained for corrosion rates and inhibition efficiencies estimations. For the electrochemical approach, mild steel samples were subjected to potentiodynamic polarization experiments in the different C₁₆H₁₃N₃O₃ concentrations in 0.5 M H₂SO₄ that were employed for the gravimetric technique for obtaining instrumental readout of corrosion rate. Results showed that the corrosion rate from the electrochemical experiments exhibited excellent linear correlation (R = 99.91; Nash-Sutcliffe Efficiency = 99.83) with the dataset obtained from the gravimetric corrosion assessments. Both the gravimetric and electrochemical monitoring of mild steel corrosion gave inhibition efficiencies, η > 90%, by the different C₁₆H₁₃N₃O₃ concentrations for the study. Also, homeoscedastic and heteroscedastic student's t-test statistics indicated that the differences between the corrosion inhibition efficiencies from the electrochemical and gravimetric techniques were not significant, p-value = 0.9729, but significant for their corrosion rates: 1.52 × 10^–6 > p-value > 8.15 × 10^–9.

Just like other solar cookers, the solar box cooker needs energy gotten from the sun to operate without producing emissions. In this research, a solar box is fabricated to reduce over-dependence on fossil fuel for energy generation. This reduces the environmental degradation caused by the use of other sources of energy. The ASHRAE empirical model was used to obtain the solar irradiance present in Omu-Aran metropolis. Thereafter, the no-load and load test was conducted to determine the cooker's thermal performance. The tests were conducted between January 2018 and January 2019 in Landmark University, Omu-Aran, Kwara State, Nigeria with geographical coordinates 8° 8' 0" North, 5° 6' 0" East. The average energy and exergy efficiency of the cooker were 32°C and 28°C respectively. A decrease in the efficiency of the cooker was observed. This was because the reflector, which is made from aluminium foil, was degrading. As a result of this degradation caused the sun rays (radiation) to be reflected poorly into the absorber and also caused a myth of overcast sky. Meanwhile, the variation in solar radiation during the sensible heating test resulted in the fluctuation inefficiency. The ratio of water to absorber temperature which was above 0.80 during the pre-boiling heating process indicates that the cooker can be recommended for sterilization.

Continued development of the minimum invasive interventional technology in recent years has proven ablation therapy to be a safe and effective local treatment for cancers and has become increasingly important in the medicine. This is the reason for its preference for treating larger tumors than for radiofrequency ablation. The authors studied the influence of the geometry of the antenna used on the efficiency of the procedure to obtain a thermal lesion at the site of the tumor. The influence of the position of the coaxial antenna on the extent of the thermal lesion at the site of the tumor was investigated numerically by varying the distance from the position of the end of the antenna with COMSOL Multiphysics as the modeling tool. The coaxial antenna investigated has a 1.79 mm diameter range with a center conductor of 0.29 mm diameter and Tefzel ETFE as the material of the catheter. The power of the coaxial antenna was optimized with a slot spacing of 6 mm from the tip of the antenna. The total power dissipation density, and thus the degree of thermal damage generated during the process was found to depend on the position of the slots of the coaxial antenna.

The paper attempted to examine the impact of manufacturing sector output on economic growth in Nigeria from 1981 to 2016. The study employed secondary data sourced from the Central Bank of Nigeria statistical bulletin for Autoregressive Distributed Lag (ARDL) model and the Granger causality techniques on RGDP, manufacturing capacity utilization (MCU), manufacturing output (LMO), government investment expenditure (GINVEXP), money supply (LM2) and interest rate (INR). Evidence of long-run and short-run relationships among the variables was established. The results showed that MCU has positive influence on RGDP while LMO also affects RGDP positively. It also showed that GINVEXP has negative effects on RGDP whereas LM2 influenced RGDP positively. Moreover, the result indicated a unidirectional causality between RGDP and MCU, LMO and LM2. Based on the above, the study suggest government should intensify efforts to promote socio-economic infrastructural, macroeconomic and institutional framework in Nigeria to provide favourable environment for external and domestic institutions interactions; so harnessed mobilized funds effectively towards productive manufacturing sector.

The optimum conditions for the fermentation of a local legume known as African locust bean (Parkia biglobosa) into a vegetable protein based food condiment or spice (Iru) were developed using Levenberg-Marquardt (or Powell) method (using PSI software) with three (3) variables namely; inoculum concentration (bacillus subtilis), temperature and the fermentation duration. P. biglobosa seeds were fermented at various temperature of 40 - 70 °C for five days (120 hours) with different concentrations of Inoculum. The proximate analysis shows that fermentation increased the percentage protein. Protein had the highest composition with about 51 % after 72 hours at the lowest fermentation temperature of 40°C.

This research work presents the use of statistical method (regression analysis) to predict early age strength of concrete. Freshly prepared concrete samples were poured into cube moulds and exposed to pond curing for 7 and 14 days. NDT was carried out using Schmidt rebound hammer before subjecting the concrete cubes to DT method using compression machine. Mathematical models were developed to obtain the early age strength of concrete for different days. From the results, concrete cured for 14 days had higher strength values than those cured for 7 days. Also, the rebound hammer in the horizontal position yields a better representation of compressive strength than when placed vertically downwards. The cubic regression (0.0198) analysis is best for the prediction of the concrete strength for the 14 days curing.

Computational Fluid Dynamics has been used for optimisation of industrial applications with some level of success. The modest accuracy provided by some of the combustion models in use has left some room for research and improvement. Coal is presented as a fuel with complex chemical properties due to its fossil fuel nature. The devolatilization process of coal is investigated with special attention to the best models that can handle heavy and light volatiles found in coal. The heterogenous char combustion is also presented paying attention to the nature of the char particle whilst it is in the process of combustion. The other processes such as drying, homogenous volatile combustion, radiation models, particle tracking models and turbulent models are investigated in a general manner as they rarely vary with the type of fuel being investigated. A summary of the industrial applications that have successfully utilised the CFD models for optimisation of coal combustion are presented thus helping in drawing the final conclusion.

The effect of Zirconium dioxide (ZrO₂) as additive to Zn-MgO electrolytic chemical bath coating by co-deposition on carbon steel was investigated. Weight loss was conducted on the electrodeposited mild steel and it was inspected. The anti corrosion properties were assessed by linear polarization procedure in 1 mole of HCl medium. From the results gotten, all deposited coatings displayed significant improvement. An amazing improvement was accomplished in every one of the coatings as against the as-received sample. Zn-MgO-ZrO₂ (0.8V) with the best performing coating showing an upgrade indicates enhanced anti-wear and friction qualities displaying wear resistance improvement.

Inventory management is central to production planning and control particularly in multi-stage production environment where production output is stochastic and customer demand is also stochastic. Surplus inventory ties down money and stock-out situation result in loss of value and goodwill. Therefore, it is necessary determine optimal inventory policies for different manufacturing scenarios to maintain a balance between safety stock inventory and customer demand satisfaction at all time. Consequently, this review attempts to identify and document the underlying trends and most recent methods of inventory replenishment under stochastic demand with emphasis on multi-stage production setting. Prominent in literature among the models used to treat inventory problem in stochastic demand situation is "Approximation by Probabilistic Distribution". Other models used include, Genetic Algorithm (GA), Just-in-time with Kanban simulation, Markov Process Decision, Fuzzy Inventory Model, Multi-stage inventory-queue model and Demand forecasting among others. It appears that there exist only approximate solutions than exact solutions in solving stochastic demand inventory problem suggesting that there is need for more work to be done in the area toward achieving exact solutions to the problem than approximation.

Prediction of elastic behaviour of polymer-based nanocomposite using finite element method (FEM) has attracted the attention of many researchers in the past few years. In this study, ANSYS 19.2 software was used to predict the elastic modulus of high-density polyethylene (HDPE) reinforced with single-walled carbon nanotubes (SWCNTs) at different weight fractions. Three-dimensional (3-D) representative volume element (RVE) was created by FEM using ANSYS software to estimate the elastic modulus of HDPE based nanocomposite reinforced with SWCNTs nanoparticles at 0.2 wt%, 0.4 wt%, 0.6 wt%, 0.8 wt%, and 1 wt% weight fractions. To present the FEM model for predicting the elastic modulus of HDPE/SWCNT nanocomposite, the results from atomic modelling were extracted and used for properties of matrix and fibre interface. The interfacial region was used in the model to separate the conditions of load transfer between the HDPE matrix and SWCNT fibre. Two density fractions of HDPE/SWCNTs nanocomposite were also used in terms of two different densities for both HDPE and SWCNT to investigate their effect on the elastic modulus. The modelling results showed that the increase of weight fraction of single-walled carbon nanotubes (SWCNTs) results with the increase of relative elastic modulus of the nanocomposite. The results also showed that the elastic modulus of low-density fraction HDPE/SWCNTs nanocomposite improves more compared to one of the high-density fractions at the same SWCNTs weight fraction. Rule of the mixture was also used to predict the elastic behaviour of HDPE/SWCNT nanocomposite and the results were compared to those of the FEM model for validation.

The subject of nanofluid have been a major topic of research due to its numerous thermo-physical properties and several breakthroughs that have been recorded. Despite this, other challenges have also ensued. In this work, efforts were made to review the breakthrough, challenges that have been recorded in nanofluid applications as regards thermal conductivity. Thermal conductivity is a significant criterion to consider when dealing with heat transfer related works and several factors affect the performance of this systems; factors such as temperature, nanoparticle size, the method of preparation of nanofluid, volumetric loading, nanoparticle shape and base-fluid used. The result of the review showed that despite the success recorded in enhancing of these systems; by employing nanofluid to improve these systems there are still challenges that portends from the use of nanoparticle. Hence the need for further researches to done in order to address these issues

This study assessed the effects of the varying ratio of alkaline activators on the short-term mechanical property of slag-based geopolymer concrete (GPC) incorporated with corncob ash (CCA). Consequently, the study harnessed the waste products, eco-friendly and low-carbon footprint materials, ground granulated blast furnace slag (GGBFS) and corncob ash (CCA) as binding agents in a bid to design and develop a sustainable product. Moreover, sodium hydroxide (NaOH) solution and sodium silicate (Na₂SiO₃) gel were used as a catalytic liquid system (CLS) for the activation of the concrete products at the varying ratio of 1.5: 1, 2: 1, 2.5: 1 and 3: 1 for Na₂SiO₃ gel: NaOH solution respectively. Furthermore, GGBFS was replaced by CCA in 20, 40, 60, 80, and 100% volume using grade 30 MPa concrete (M 30) as a mix design proportion. The mix was activated with 14 molar concentrations of CLS. Subsequently, the concrete samples were cured under the ambient conditions and tested for compressive strength at 7, 28, 56 and 90 days. The experimental finding revealed that the optimum strength performance of slag-based GPC incorporated with CCA is achieved at a ratio of 2.5: 1 for Na₂SiO₃ gel: NaOH solution respectively when compared with 1.5: 1, 2: 1 and 3: 1 for the concrete. Therefore, the strength performance of GPC depends on the varying ratio of alkaline liquid and must be properly experimented to ascertain its best performance on the strength properties of GPC.

One of the variables that significantly affect the joint integrity of welds carried out with friction stir welding (FSW) is the tool pin geometry. This particular factor considerably affects the mechanical properties, joint size and microstructural evolution of the weld. The extent to which tool geometry affects the mechanical behaviour of welds under different processing parameters needs to be fully understood in order to achieve highly reliable joints for various industrial applications. This work is, therefore, an attempt at, investigating tool pin geometry and processing parameters effects on the mechanical behaviour and stability of friction stir welds through joining of 6101-T6 and 7075-T651 aluminium alloys via FSW. Two pin designs named tapered unthreaded and tapered threaded were used for this study. The result obtained shows that low rotational speed and high welding speed promote the tensile strength of the welded alloys and that welds carried out with the tapered threaded tool gave higher tensile values than the tapered unthreaded.

This paper outlines the unique role of Crateva adansonii (CA) leaf extract on low carbon steel in corrosive media. The defensive ability of Crateva adansonii extract was evaluated by gravimetric and gasometric techniques. The result of the experiment indicated that extract of Crateva adansonii exhibit perfectly well on the steel due photochemical species containing in the inhibitive extract thereby blocking both the anodic and cathodic site. The mixed Inhibitive effect of Crateva adansonii were investigated by the kinetic state. The adsorption studies of CA leaf extract obeyed the Langmuir, Freundlich, temkin isotherm but best fitted into Langmuir adsorption isotherm which characterised by physisorption. The range of E_a values (from 46.09 kJ/mol to 60.58 kJ / mol) in the presence of the extract being higher than the free solution. Which suggests strong physical adsorption (physisorption).

The research work investigated the production of adhesive from cassava starch. Cassava tubers were processed into starch-based adhesives, using two different gelatinization enhancers (that is HCl and NaOH) which were introduced separately. The adhesives were produced by considering two varied process parameters, namely percentage weight of borax in starch solution (8 – 20%) and reaction temperature (65 – 85°C). Comparative analysis of the adhesive obtained (using HCl and NaOH as gelatinization enhancers) include the determination of its bond strength, viscosity, drying time, pH and density. As the borax weight percent increases up to 14 % and reaction temperature reduces (using NaOH) the drying time increases, while the drying time reduces as both the borax weight percent and temperature reduce (using HCl). The results of the adhesive physical properties fall within the standard range for each of the properties and this implied that the adhesive produced was of high quality.

This study used Artificial Neural Network (ANN) for the prediction of power required to inflate different tyre sizes and inflation times. ANN is a widely accepted machine learning method that uses past data to predict future trend. An existing database obtained experimentally from a tyre pressure control test rig was optimized using genetic algorithm(GA) which is an optimization tool that can find better subsets of input variables for importing into ANN. The ANN results were compared with the results obtained experimentally. The results show that the model can be implemented in modern day tyre pressure control designs and be used to predict inflation times and power required to inflate different tyre sizes.

Kinetic studies of heterogeneous catalytic reactions form a crucial step necessary for the understanding of catalytic behaviour of a catalyst towards designing, controlling and optimizing a reactor. This study reports kinetics of waste animal fat oil (AFO) transesterification to biodiesel using waste-derived heterogeneous catalyst, hydroxy sodalite (HSOD) in a batch reactor. The catalyst was synthesized from coal fly ash and waste industrial brine via hydrothermal treatment. At a temperature range of 49 - 62 °C and a time range of 30 -120 minutes, the transesterification of animal fat oil to biodiesel was conducted at a fixed methanol/oil mass proportion 9:1, percent mass weight of catalyst 3 (based on the AFO) and stirring intensity of 300-500 rpm. Experimental findings reveal that reaction rate, which is first-order, was anticipated to increase with increasing temperature, resulted in an activation energy and a pre-exponential factor of 58554.65 J mol^-1 and 2.83 min^-1, respectively. The value of the activation energy suggests that the reaction is endothermic and a minimum energy of 58.55 kJ is required to achieve an effective collision at a frequency of 2.83 min^-1. The highest biodiesel yield was 90 % at 62 °C and this corresponds to a highest AFO conversion of 93 % at a reaction time of 120 minutes.

The study of heat transfer is crucial for its proper implementation in engineering design process. The Shrinking Boundary Monte Carlo Method was applied to evaluate temperature distribution in a Spiral, vertically up and vertically down running direction. The outcome was equated to normal Monte Carlo Method. The results revealed that increasing the size of the rectangular slab will increase the running time to compute temperature distribution. In a given direction of running, it has different temperature distribution for the different sizes of the slab. The computational run time for a rectangular slab in a portrait shape is greater than rectangular slab in a landscape pattern. The study proved that the average of the run time for various direction of movement indicates that spiral is shorter. It is the best ways of computing temperature dispersal in a rectangular slab of fixed boundary condition. The utilization of the shrinking boundary to analyse heat transfer was successful.

Most papers are made from virgin wood-based pulp of hardwood sources but recently, softwood have received enormous attention as alternative to hard wood because the hardwood takes a significant number of years to mature enough for use in the pulp and paper industry unlike softwood which are majorly annual plants. The annual crop in focus in this work is the yellow open-pollinated variety of corn which generates tons of waste at harvest. A novel attempt is made to ascertain the viability of corn sheaths as raw material for the pulp and paper industry by carrying out a comprehensive analysis on the pulp and paper made from the pulp. The sheaths were dried, shred and cut into pieces suitable for the digester and the pulps obtained were analysed for physico-chemical properties. Hand sheets were also made using the generated pulp and its physico-mechanical properties were analysed. Results obtained were compared with pulp from corn husks from other parts of the country, three Nigerian fibre sources – silk cotton, bagasse and rice straw and other foreign non-wood sources and found to be of competitive properties. Pulp properties of Lignin content, ash content, cellulose, hot and cold water solubility of the fibres were 13.72 ± 1.21%, 1.27 ± 0.23%, 53.26 ± 1.11%, 15.20 ± 2.11 and 6.14 ± 2.43 respectively while the mechanical properties of paper from the pulp were Bursting strength (282.163 KPa m²/g), Tear strength (146.119), Tensile strength (257.6N/m) and Tensile Index (3.9Nm/g). It was found that in all properties, the corn sheath was better than the rice straw fibers but not as good as the silk cotton and bagasse fibers. However, the corn sheath has been identified, as a viable raw material for the pulp and paper industry in Nigeria.

This work aimed to study the aluminosilicate ore contents at Lafarge Ogun State environ as a means of identification of background variation of smectite in the ore-bodied environment. Smectite clay samples (bentonite) were collected from Larfarge Ewekoro environ, while zeolite used as a standard in this work was obtained from Petroleum Department of Covenant University for comparism purpose. The samples were digested with nitric acid, HNO₃ and hydrochloric acid, HCl, after which the digested samples were characterized with, ultraviolet visible (UV-VIS), scanning, absorbance; and % transmittances. The results revealed similarity in ultraviolet visible for bentonite and zeolite with predominance of iron in bentonite samples. The colouration of bentonite due to the presence of transition metals in the environment under study could be of industrial uses in the manufacture of coloured wares and tiles, and magnetic ceramic, though further pre-application specific investigations are recommended. Also, the observed properties favour many aspects of industrial applications such as in pharmaceuticals, refractories, adhesives and porcelain wares. These will help in setting up small and medium-sized enterprise in this area resulting in employment creation and revenue generation.

This research lays emphasis on predominant corruption stories in popular Nigerian newspapers, by means of fantasy-theme analysis in reviewing issues that concern corruption within the Nigerian political sphere. Particularly, this analysis compares stories about Nigerian politicians who have been reported at various points in time by Nigerian newspapers as corrupt individuals, who in one way or the other were found guilty of syphoning funds and falsifying relevant information. Through a thorough examination of fantasy themes roles on these accounts and recognizing which parts of reality are significant, we conceive what the messages are able to achieve with regards to the creation of rhetorical visions within contexts of symbolic convergence theory. In this study, fantasy themes analysed disclose meanings regarding morality, personal decisions, and class privilege. This study also highlights how stories on corruption cases by political leaders could help in the establishment of proper, honourable societies that punish or reprimand certain corrupt behaviours via normative impact on audiences. Fundamentally, rhetorical visions derived in this paper suggest that decision to be corrupt or not, as a politician lies with the politician himself.

Theory of chatter-suppressing wave attenuation effects in high-speed metal cutting process is presented in this work. Analysis shows that rise in natural frequency of cutting tool leads to rise in the wave attenuating forces. This result leads to the postulation that rise in natural frequency suppresses high-speed chatter instability. The theory is based on the assumption of very short free-flight of cutting tool, and shown to fail when this assumption is violated. The concluding opinion becomes that the resistance of a high-speed tool to chatter stems from both structural damping and wave attenuation effects.

This paper presents the result of experimental comparison of the video quality of streamed videos using streaming devices and streaming platforms. The objective metrics considered for the comparison of these media are the Peak Signal-to-Noise Ratio (PSNR), Structural Similarity (SSIM), Visual Information Fidelity (VIF), Information Fidelity Criterion (IFC), and Visual Signal-to-Noise Ratio (VSNR). To determine the better platform for effective multimedia applications especially for educational purposes, videos were obtained and streamed via Data video, YouTube and Facebook. In the first two scenarios, Data video at two different settings were engaged at the encoding end and PotPlayer was used for decoding and recording of the transmitted videos. In the third and fourth scenarios, Videos were streamed via YouTube and Facebook. The aforementioned objective metrics were implemented in MATLAB R2017b for the experimental analyses and our results showed that YouTube produced streamed videos of the best quality with PNSR of 37.98, SIMM of 0.98 and VSNR of 33.12.

Over the years, there has been increasing interest in exploitation of renewable energy source (RES) as a result of fast depletion of fossil fuel based conventional power generation with attendant negative environmental impact. However, renewable energy sources such as solar, wind, biomass etc are not always available because of their fluctuating nature. In view of this, it has become imperative to have an efficient energy storage system (ESS) for sustained energy availability. Batteries storage often suffers early failure due to irregular charge and discharge cycle which could eventually shorten its life span. Therefore, this research focuses on investigation of the influence of meteorological parameters on battery storage in solar PV system as well as evaluating the influence of these factors on the performance characteristics of solar PV storage system. The work examines particularly the effect of varying solar temperature and irradiance on the system output charging current and overall efficiency. A modified mathematical model of a solar PV was developed to show the relationship between meteorological parameters (irradiance and temperature), and PV output short circuit current. Analysis of meteorological data obtained for determination of state of charge (SOC) of battery storage based on the six geographical areas in Nigeria revealed that, in Bornu state (North-east) the battery attained 100% (hundred percent) state of charge in1Hr (one hour), while in Plateau state (north-central), the battery attained 60% (sixty percent) state of charge in 8hrs (eight hours), being the least in terms of charging rate. In Kaduna (North-west) region, the battery attained 88% state of charge in one hour and 96% SOC after duration of eight hours. This is quite different from Lagos (Southwest), where the battery SOC in one hour was 38% and 78% SOC in eight hours. This phenomenon therefore, revealed that solar PV system implementation should be site specific and it also account for the life span of the storage and the system efficiency.

Carbon black (CB) is a very important material useful for various modern applications. There are a lot of attention currently on the extraction of a form of CB obtainable from waste tyres which is usually referred to as pyrolytic Carbon black (CBp). The authors investigated the pyrolysis process of a pyrolytic furnace built for the production of CBp using the thermal numerical principles to standardise the application. SolidWorks@ Flow Simulation software was used to replicate the process by supplying the initial conditions, the boundary conditions and the operating conditions guided by the numerical analysis. The simulated behaviour of the furnace was validated by the real-life experiments performed to produce CBp from the waste tyre.

In energy recovery technology, via municipal solid waste (MSW) as an energy resource; the capacity of the power plant required can be designed, if the potentials of the heat and electrical energy of the waste to be combusted has been established. Conversely, in this research, the amount of power potential of the waste required as fuel, is determined through the design for the capacity of the steam power plant that will utilize municipal solid waste as an energy resource. The capacity of the power plant is designed, using single reheat Rankine cycle. The pressure and temperature selected for the design of the boiler is 30 bar and 400 °C, the pressure at the reheat tube is 6 bar, and the pressure at the condenser is 0.032 bar. The heat supplied to the boiler is calculated to be 3639.2 kJ/kg, the total work-output of the turbine is 1451.4 kJ/kg and the heat rejected at the condenser is 2187.6 kJ/kg. The quantity of MSW required is predicted to be 418 MJ/kg based on the calorific value of 20 MJ/kg, and its heat energy and electrical power potentials is predicted to be 2.3 GWh and 29 MW respectively while the grid to power is 20 MW.

Material testing machines are necessities in structural metal industries and engineering training institutions. Cost of importations had however made acquisition of the equipment difficult in most developing countries. This research aims at developing a hardness testing machine with 100% locally sourced components with a level of accuracy comparable with globally recognized manufacturers of similar equipment. A 5-Ton capacity Brinell-type hardness machine was designed, developed and tested. The machine has dimension specification: Base (602mm × 602mm); Height (1219.2mm). Total weight is 135kg. The cubical frame is made of two structural I-channel of depth (600mm) ×width (65mm) ×web (5mm). The horizontal I-channel that absorbs the bending load is of specification 600mm Depth ×65mm width×5mmWeb. Design indentation load of 50000N transmitted at the centre of I-channel was used resulting in maximum stress of 48.5N/mm². A 5-Ton hydraulic jack, with attachments for workpiece support is placed rigidly on the lower I-channel. Sperical steel ball from ball bearings was used as indenter ball, positioned in a casing and rigidly fixed to the upper channel of machine in inverted position. Hydraulic jack pressure was monitored through a oil pressure meter connected through an orifice at the base. An upward movement of the ram lifts workpiece against stationary indenter. Indentation diameter on workpiece is measured with a micrometer travelling microscope. Repeated tests carried out on Aluminium, Copper and plastic gave diameters 2.9, 3.2, 7.5mm coressponding to 74.098, 60.56, 9.5BHN. Similar tests carried out on Brinell Hardness Tester Model (EEDB) and serial number (EEDB/13) give 79.6, 69.1, 9.5BHN percentage variation of locally developed machine from the standard machine used were 6.91, 12.36 and 0%. The effect of applied indenter force on hardness value was examined and results showed a maximum range of 1.428 BHN standard deviation. Test results indicated good reliability for use in basic material testing.

Cloud computing is a desirable paradigm that is providing services to users in a convenient manner and ensuring that Cloud service providers have value for their infrastructure. Applications designed to run explicitly on the Cloud are usually referred to as Cloud-native applications. Determining a research focus in a particular field of study is sometimes challenging. A systematic mapping study gives an insight into the research level that is being conducted in any field of interest. The results generated from such study are presented using a map. The method used in this study was analyzing three facets categories namely, topics, research and contribution. Topics were retrieved from primary studies, while type of research such as evaluation and contribution such as tool, were used in the analysis. The objective of this study is to conduct a systematic mapping study of Cloud-native applications designs and engineering. This will provide an insight into the frequency of work that has been done in cloud-native applications area. The results showed that from publications relating to security in the field of metric (1.94%), more articles in the topic of application in terms of tool (13.59%), more work done on architecture in terms of model (15.53%), more papers published on Cloud migration in the area of method (10.68%). Furthermore, 11.82% publications were identified on applications in terms of evaluation research, more publication on implementation in the area of validation research (1.82%), more publications on implementation in solution research (6.36%), more publications on security and application with respect to philosophical research (1.82%) and more work done on applications in terms of experience research (6.36%). From the study, several gaps were identified which would be beneficial to researchers, practitioners and providers.

In this work, aluminum thin films were sputtered on steel substrates at a varying substrate temperature ranging between 40 and 100 degrees Celsius. The films were characterized for microstructure by field emission scanning electron microscope, topography by atomic force microscope, mechanical properties by nanoindentation and the results related to the wear behavior of the films under very high sliding load of 30 N. The mechanism of failure of such films were observed and the relationship between the substrate temperature and sliding failure discussed. The study is important in understanding the failure mechanisms and improvement of the surface properties of sputtered aluminum thin films.

Forging is one of the conventional shaping technologies that is widely used for the manufacture of quality products for various industrial applications. The process involves the mechanical application of a punching force to deform a material to the desired shape and improved properties. In most cases, the manufacture of quality products depends on the experience of the designer and trial and error method thus making the process wasteful and costly. The present study reports on the application of finite element method (FEM) for the analysis of the effect of punch force on the stress/strain distribution during the deformation process as a step towards the reduction of trial and error methods in practice. The results show that increase in the punch force leads to inhomogeneity in the strain/stress distribution due to change in the deformation temperature resulting from the internal heat generated during plastic deformation stage and the frictional force at the punch-workpiece interface. It is also observed that the maximum effective strain occurs at the center of the deformed sample and the maximum effective stress occurs at the low effective strain regions. Moreover, the friction parameter increases as the punch force increases.

Foundry practice have existed in Nigeria for centuries. However, for the development of the practice, know-how and skills must be developed. Personnel must be trained at all levels. In this study, the practices in foundries of research and academic institutions involved in foundry within Lagos state were investigated. Investigations were carried out by on-site study of the foundries and also by means of questionnaires investigating various aspects of foundry practice. From responses obtained, it was shown that the capacity of foundries to produce technically sound castings is very low. Simple steps capable of increasing the quality and reproducibility of the castings were suggested. It was concluded that students' learning and local foundry practice can be enhanced by upgrading foundries in research and educational institutions to current global best practices.

One of the most important concrete properties for structural concrete design or redesign is the compressive strength, it gives information on the characteristics of concrete. This strength measure is obtained through standardized crushing tests on cast cubes, the cubes are produced alongside the construction of concrete elements on site however they are not available for strength testing of existing buildings henc3e the need for non-destructive test methods. Schmidt's Rebound Hammer is a nondestructive test which is used to assess the compressive strength of concrete using rebound index. Surface hardness test was done on different concrete mix and compared with cube compressive strength tests. The changes in one variable explained by the change in a related variable as given by the R-squared are 93.79%, 99.42%, 86.8%, 1% and 98.5% for Mix 1, 2, 3, 4 and 5 respectively. It is noted that for proper result from non-destructive tests, more than one should be implored and the model calibration should be based on actual compressive strength.

The focus of this work is to develop a flexible ORC design procedure that compares thermo-economic performances of simple and recuperative ORCs for both subcritical and supercritical cycles through a multi-objective optimization that relates the economic parameters to the network output for waste heat-to-power conversion of exhaust gases. Few researches have proposed rather simpler methods by modifications to the Jacob number (Ja) but these are insufficient to make technical and economic decisions on the subject matter as Ja is only appropriate for comparing performances of different working fluids at the same operating condition. Coupled with the barrier on the minimum temperature the exhaust gases from power plants may attain, the use of Ja as the only criteria is not sufficient for varying operating condition presented by Gas Turbine power plants. Hence, this review presents follow-through numerical methodology for designing adapted ORC for waste heat-to-power energy conversion.

This paper presents a new approach to using artificial neural networks (ANNs) in improving the protection of transmission lines. The proposed method uses instantaneous values of voltages and currents during normal and fault conditions on a transmission line as inputs to four different neural network structures. The structures are then aptly combined to yield a system that can detect and classify shunt faults with improved efficiency. The details of the design procedure as well as various simulations carried out are provided in the paper. The performance of the developed system is evaluated using two performance indices, viz., accuracy and mean square error (MSE), and the results show that this approach is capable of detecting and classifying all possible shunt faults on the 33-kV Nigeria power lines in less than 1ms with high level of accuracy.

We obtained the analytical solutions of the two-body Salpeter equation via the methodology of supersymmetric quantum mechanics under a combination of Coulomb and Hulthén potentials for unequal masses. We clearly examined the energy eigenvalues for the ground state and excited states. The behaviour of energy with the sum of the masses and the screening parameter respectively, were also studied. The results showed that two bodies of unequal masses interacting within the system exhibit the same features.

Crude oil refinery is a significant manufacturing company in Nigeria, which when properly build in a good location, it will help to stable the economic instability in the country. As the end product of the crude oil process is used for different purposes such as, transportation, cooking, electricity generation and for industrial application, which will help to improve the daily living of the Nigerians. This work presents a multi-criteria analysis method for suitable selection of the refinery location in Niger Delta, Nigeria. The suggested location principle takes into consideration the technical aspect of the Environment. The four interest considered in this work are economy factor, nearness to other felicities, environment impact and traffic impact. These interest were examined for three locations alternative such as Delta state, Bayelsa state and Akwa-ibom state using Analytical Hierarchy Process (AHP) to assign weight through pair-wise comparison and Multi-criteria decision-making tool to make a suitable selection. The analytical results show that Akwa-ibom state has the highest aggregative value of the rated score of 539, Delta state of 482 and Bayelsa state of 438. The result derived from this study as proven that AHP method for selection decision making is reasonable and obtainable for refinery selection location.

Resistance spot welding (RSW) has been extensively used in the automotive and aerospace industries over the years. The weld quality of spot welds is affected by the welding parameters like electrode force, weld time, electrode current and workpiece size/shape parameters like workpiece thickness. This study focuses on the effect of electrode force, weld time and workpiece thickness on the weld quality of mild steel samples where the aim is to correlate the weld strength to welding parameters of a portable RSW machine installed at the Nigerian Liquefied Natural Gas (NLNG) laboratory of the Department of Mechanical Engineering, University of Nigeria, Nsukka. Lap shear weld samples are tested for strength, and the results are used to develop an empirical model. The developed model has a coefficient of determination of 0.6365 and a correlation coefficient of 0.7978. Hypothesis testing at 5% significance level discovered that the most significant predictor is the cross interaction of the workpiece thickness and electrode force with p-value of 0.02367 and that the model is significant with a p-value = 0.0453. The model is validated by further welding operations and tensile shear tests which gave a percentage error not exceeding 12.92% but was as low as 6.35%.

The aim of this paper is the presentation and verification of computer vision algorithms in order to measure the geometric parameters of soft robots. The materials from which soft robots are made from possess large deformations. Embedded sensors or visual processing algorithms are often used to obtain measurement performance data from these robots. Integration of embedded sensors with soft robots can be cumbersome and expensive, also limiting the performance of a soft actuator. In this paper, implemented visual processing algorithms (thresholding, SAD, SSD and ZNCC) to measure performance data such as angle of motion, degree of bending, radius of curvature in real-time implemented with OpenCV libraries and Webcam is described. Soft RGB colour markers were also produced and firmly glued into the body of the soft robot with no hindrance to movement. Some concepts of visual processing applied include colour tracking, template matching and camera calibration. The execution of vision based motion control to a variety of soft actuators such as bending and wedge-shaped soft actuators was described.

This is a review and overview of the trending researches in automobile brake pad production processes, formulations, materials, and properties. Most of the works attempt mainly on replacing asbestos found to be carcinogenic with base materials with other ingredients in various formulations and particle sizes. Though most of the replacements are non-hazardous with properties such mechanical and tribological cauterizations comparing well with the traditional asbestos based brake pad. The overview of these trends suggests the need to replace not only the asbestos but also the commonly used epoxy resins or phenolic resins or phenol formaldehyde binders that has been found to corrode outside plates of brake assembly. These reviews has thrust a new research direction of replacing the asbestos and inorganic resins with agro based materials of Cashew Nut Shell and Plant Gum binder respectively to obtain a substantially green based brake pads that are non-injurious to human health and does not corrode any parts of the brake pads assembly.

Voting is fundamental to any consensus-based society and is one of the most critical functions of democracy. Mobile voting (m-voting) was utilized as a means for voters to easily and conveniently cast their votes using their mobile devices which have been the most adopted means of communication but has a major problem which is safely securing the casted votes and avoiding any form of tampering. In this paper, we propose an m-voting framework that utilizes blockchain technology to securely store the casted votes and multi-factor authentication to authenticate the voters before they cast their votes while also providing an easily accessible, secure and transparent m-voting system.