ABSTRACT In this study, the use of purely inorganic filler materials to influence the mechanical properties of flexible polyurethane foam has been investigated. The fillers were calcite (CaCO3), dolomite (CaMg(CO))), and kaolin (ALSO(OH)) of volume fractions ranging from 0 - 40 wt%. Each of the filler content ranges was investigated at the following average particle size distributions: 0.06, 0.5, 3.5, 10, 20, and 841 um. The experiment was performed in a discontinuous foaming process based on...
ABSTRACT The focus of this research work is the unraveling of the microbial dynamics of the biodegradation of a mixture of polycyclic aromatic hydrocarbons (PAH), naphthalene, anthracene and pyrone in an aqueous- soil matrix. The soil used in these studies was characterized as highly porous with a sandy-clay ratio of 85-14%. The microbial growth study was characterized by an initial lag phase, a rapid and an exponential increase in cell biomass, a stationary phase and finally a death phase. T...
Abstract The threat of slugging to production facilities has been known since the 70’s. This undesirable flow phenomenon continues to attract the attention of researchers and operators alike. The most common method for slug mitigation is by choking the valve at the exit of the riser which unfortunately could negatively affect production. The focus therefore is to satisfy the need for system stability and to maximize production simultaneously. Active feedback control is a promising way to ac...
ABSTRACT In Nigeria, a large number of jacket platforms installed in the Niger Delta have been operating beyond design life of 25 years due to the exorbitant cost of replacement with new ones. These Jacket structures often undergo corrosion and fatigue damages due to hostile offshore conditions and accidental release of corrosive agents from crude oil production activities. Therefore, there is a growing need to closely monitor the structures to protect unexpected failures. Applications of ap...
ABSTRACT Graphene nanoribbons (GNRs), titanium dioxide (TiO2), and their composites Graphene nanoribbons/titanium dioxide (GNRs/TiO2) were employed towards the simultaneous detection of nevirapine (NVP) and glucose (GLC). The nanomaterials were characterized Fourier-transform infrared spectroscopy (FTIR), UV-vis and thermogravimetric analysis (TGA), cyclic voltammetry, electrochemical impedance spectroscopy, linear sweep voltammetry, differential pulse voltammetry, and chronoamperometry were ...
ABSTRACT The purpose of the study was to implement a frequency reuse in 3GPP-LTE downlink cellular system which was to be used as the main measurement and as analysis tool for interference mitigation and to evaluate the performance for various conditions enabling the efficient deployment and optimization of femto cells on multi-tier networks. The Mat Lab Vienna LTE simulator was used to analyses the degrading impact of interference on channel capacity when Femto-cells are deployed over a Macr...
ABSTRACT The present study designed, constructed and undertook the performance evaluation of a post harvest passive solar crop dryer for drying agricultural produce. The solar crop dryer consists of a solar collector with dimensions 110 x 61 x 10cm, a drying chamber measuring 102 x54cm, a movable heat storage unit with the dimensions 40 x 35 x 13cm and drying trays each having an area of 1806cm2. The performance evaluation was conducted using three cropstomatoes, pepper and okra which are loc...
ABSTRACT For accurate and high rate of lung cancer detection using image processing, an effective preprocessing technique is required. A quality preprocessing technique is necessary to ensure effective removal of noise that interferes with the features of the image and hence improves lung cancer detection rate and accuracy. In this research, an Improved Gaussian Filter (IGF) technique was developed for effective lung image preprocessing. For image segmentation, Otsu thresholding method was us...
ABSTRACT Simulation of complex hydrological responses in large watersheds over years has prompted the need for procedures for autocalibration. The commonly available models of watershed hydrology are of the event type applicable on a basin scale or continuous models applicable on a field scale. The Watershed Resources Management (WRM) model is a basin-scale model for continuous simulation. It is generally applicable in planning, forecasting and operational hydrology, to the study of environme...
ABSTRACT Energy benchmarking and carbon footprint reduction opportunities in Portland cement manufacturing processes in Nigeria are presented. Life Cycle Assessment (LCA) is used to estimate the environmental impact of three cement manufacturing processes in Nigeria. The energy consumption of the cement manufacturing processes are evaluated using energy Benchmarking and Energy Savings Tool for cement (BEST-Cement). BEST-Cement evaluates and compares the energy consumption of the cement manufa...
ABSTRACT Telecommunications companies, over the last decade, have undergone major change in terms of the manner in which they do business. The objective of this study was to investigate the impact of change implementation on staff turnover in telecommunications industry by reviewing the following key issues, the effect of change implementation on staff turnover, the implementation of change within the industry, the communication of change initiatives by management in the industry, and the eff...
ABSTRACT Multiphase induction machine offers numerous advantages compared to the conventional three phase induction machine. It is an upgrade from the conventional three phase induction machine. By splitting the phase belt of a three phase, a sixphase machine is realised. The areas of application of multiphase machines are enormous, mostly where reliability is paramount. This research presents the modelling and implementation of a split phase induction machine with Saturation and skin effects...
ABSTRACT Abakpa-Nike is notorious for chaotic traffic due to driver's indiscipline and poor road nehvork. This study was therefore undertaken to determine the level of traffic congestion at four major intersections: The Abakpa-Nike- Trans-Ekulu T-Junction; Abakpa-Nike Liberty Junction; Afia Abakpa Junction and Nowas Roundabout Intersection in Abakpa-Nike area of Enugu, Enugu State. These intersections are notorious for high traffic volumes. Vehicular traffic volume were measured to quantify o...
Abstract Pedestrian visitors at Gweru General Hospital are facing challenges crossing the Shurugwi road into the hospital premises due to high vehicular traffic influx to and from town. Thus this Arduino based pedestrian crossing control system has been designed to give priority to these pedestrians so that they can safely cross this perilous main road. The system incorporates the concept of passive pedestrian detection to sense the presence of pedestrians and in turn automatically controls t...
ABSTRACT This work presents the synthesis of a motor with hysteresis motor torque-speed characteristic. The machine is synthesized from a conventional squirrel cage induction motor (SCIM) with high rotor resistance to leakage reactance ratio and a polyphase transfer field (TF) reluctance effect machine with an inverted torque-speed characteristics about the speed axis. Both motors are mechanically coupled and are connected in parallel to the supply. It is shown that the resultant torque which...