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URBAN GOVERNANCE AND THE ENVIRONMENT IN ABA AND ONITSHA
Get PDFGovernance capacity determines the effectiveness of urban environments and systems. Thus, unplanned landscapes and poor land management as commonly observed in Nigeria’s cities, are a reflection of poor governance. This has led many researchers to conclude that these spaces are characterised by the “absence” of public sector governance. Following the 2016 World Health Organisation declaration of Aba and Onitsha amongst the world’s 20 worst cities by air quality, this paper reviews environmental problems in thesefunctionally similar locations to ascertain the “presence” or “absence” of governance in their respective environments. Data for the study was obtained from secondary sources: published literature, substantive news articles, the archives and from the authors’ field observations. 
AN ENHANCED SPATIAL PULSE POSITION MODULATION FOR ULTRA-WIDE BAND (UWB) COMMUNICATION LINK
Get PDFTransmission rate and bit error rate (BER) performance are two important parameters for ultra-wideband (UWB) communication system. Among the widely used modulation schemes, pulse position modulation (PPM) is attractive for its high energy efficiency. However, PPM scheme suffers low data rate and poor bit error rate performance due to the symbol pattern (duration) required for high number of M bits. The study employed combination of Spatial Pulse Position Modulation (SPPM) and On-Off-Keying (OOK) in order to improve the BER performance. While SPPM results in high bit error rate performance, the OOK is predicted to improvethe BER at low signal to noise Ratio (SNR). The enhanced scheme combined SPPM and OOK, results has an improved BER by an order of two and an increase in the data rate by two orders of magnitude relative to the standard PPM. The study revealed that two schemes could be combined to enhanced transmission rate and low SNR. The scheme could be recommended optical communication system (OCS). 
Free Vibrational Effect of Foot Bridge with Compressive Forces
Get PDFThis paper examines the free vibrational effect of a footbridge with compressive forces. The governing partial differential equation were analysed to determine the behaviour of the system under consideration. The methods of series solution and numerical method were used to solve the governing equation. Result revealed there is no noticeable effect of damping in the system as the motion of deflection remains constant for all values of the damping coefficient. Also, the lateral displacement increases for various values of spring constant
SOLVABILITY OF THE THIRD-ORDER KORTEWEG-DE VRIES (KDV) EQUATION BY VARIATIONAL ITERATION AND NEW ITERATIVE METHODS
Get PDFThis paper examined the approximate solution of the third-order Kortewed-de Vries (KdV) equations is obtained by the Variational Iteration Method (VIM) developed by Ji-Huan He and the New Iterative Method (NIM) developed by Daftardar Gejji and Jafari. These methods provide the solution in the form of a convergent series.which illustrate the ability and the effectiveness of the methods, some examples were provided. The results showed that the methods are very simple, effective, powerful and can easily be applied to other linear and nonlinear PDEs
REGULARIZATION TECHNIQUES IN MULTIPLE LINEAR REGRESSION IN THE PESENCE OF MULTICOLLINEARITY
Get PDFMulticollinearity has been a serious problem in regression analysis. Ordinary least square (OLS) regression may result in high variability in the estimates of the regression coefficients in the presence of multicollinearity. Least Absolute Shrinkage and Selection Operator (LASSO), Ridge Regression (RR), and Partial Least Squares (PLS) methods are well established methods that reduce the variability of the estimates by shrinking the coefficients and at the same time produce interpretable models by shrinking some coefficients. The performances of LASSO, Ridge Regression, PLS and OLS estimators were evaluated using Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC) in the presence of multicolinearity using Monte Carlo Simulation. The simulations were done for different sample sizes: n (10, 50, 100, 150) and levels of multicollinearity: Mild (0.1 – 0.3), Low (0.4 – 0.6) and High (0.7 - 0.9). OLS had poor parameters estimate and produced wrong inferences, LASSO estimator is the best, while PLS is most efficient when the number of variable is greater than sample size. 
LINEAR PROGRAMMING APPROACH TO MODELING FOUNDRY CUPOLA FURNACE CHARGE
Get PDFIn order to control the specifications of the cast iron produced by the cupola furnace, it is necessary to estimate the proportions of the contents of the furnace charge. Traditionally, knowing the percentage of elements present in each constituent of charge and the loss or gain of each element, the final analysis of cast iron can be estimated by trial and error approach - a common approach in most Nigerian foundry workshops. This study presents a programming model technique used to obtain the optimum cupola furnace charge. The objective function was to minimize total cost of raw material and processing costs. The model was developed and implemented using the hypothetical process data of a Foundry workshop. The model was analysed using MATLAB Software Version 7.0. The results obtained using the model is significantly superior to the conventional trial and error approach. It is faster and brings about satisfying a lot of requests at the most minimal expense. 
TEMPERATURE EFFECTS ON PV MODULE OPTIMAL PERFORMANCE
Get PDFThis research was carried out to study the effects of Photovoltaic (PV) module temperature on its performance. The relationship between Module temperature and other parameters that determine the optimal performance were evaluated using Pearson product correlation in built in Microsoft Excel. The research has shown that PV module temperature among other factors has a great effect on the PV optimal performance
ASSESSMENT OF HEAVY METAL CONTAMINATIONS OF SOILS FROM DUMP SITES IN JOS METROPOLIS, NORTH CENTRAL NIGERIA
Get PDFA study was carried out to determine the heavy metal contamination of the soils in three refuse dumpsites in Jos metropolis located in Rayfield Resort, Dariye Park and Farin Gada within the Jos-Bukuru Complex of Younger Granite Province of northcentral Nigeria. Six (6) soil samples were collected at depth of 40 cm from the three dumpsites. The soil samples were subjected to X-Ray fluorescence (XRF) analysis to determine the concentrations of heavy metals. The values of heavy metals in the soils from the three dumpsites were foundto be: zirconium (382.537-1045.734 ppm), strontium (54.584-185.030 ppm), uranium (8.496-12.055 ppm), rubidium (60.189-111.280 ppm), thorium (13.305-30.138 ppm), lead (26.790-277.342 ppm), arsenic (7.971- 27.819 ppm), zinc (129.790-734.643 ppm), copper (31.899-247.048 ppm), nickel (42.454-72.670 ppm), iron (22162.547-64319.262 ppm) and manganese (214.146-449.344 ppm). 
RELIABILITY ASSESSMENT OF POWER DISTRIBUTION FEEDERS
No full textThe study focuses on the analysis of 33kv distribution feeder network in Ibadan Electricity Company, Ota. The main aim of this research is to estimate the reliability of 33-KV feeders which are secondary distribution network of the system. The study determines the Failure Rate, the Mean Time between Failures (MTBF), Mean Time to Failure (MTTF), Availability and reliability of the network. This study uses statistical analytical method. Statistical analytical methods provide useful and higher accuracy of result since it provides high tolerance to uncertainties. The result shows that the mean reliability of the supply system was 74.41%, and thus for a developing nations like ours, the reliability is partly satisfactory. 
Evaluation of Rural Water Supply Schemes in Selected Communities in Orire local government, Oyo State, Nigeria
Get PDFOperation and maintenance of water supply scheme is one of the challenges militating against sustainable water provision in rural areas. This study focused on the evaluation of water supply scheme in selected communities in Oriire Local Government of Oyo State. The study involved assessment of the available water supply scheme, its sustainability level and the quality of the water facility. Field work involved the use of structured questionnaire to obtain information and data on socio-economic status, water use, accessibility,functionality while the water quality of the non water supply scheme (river water source) was determined at the laboratory. Chi square, T-test and Kruskal-Wallis test were used to analyse the data obtained from the field. The study revealed that there is irregular supply of water from the water supply scheme due to inadequate planning for maintenance and rural water supply scheme is not sustainable. It was observed that when local communities participate directly in planning their water supply systems, these systems are more likely to be sustainable than systems that are imposed by government or donor association. The tested drinking water quality was found to be adequate in term of pH, biochemical oxygen demand, chloride ion, total dissolved solid and total hardness. For the water sample tested, all these were generally good except turbidity which was higher than 5NTU. The stream water in the community can also be developed to be the part of water supply scheme.