Abstract: This research is aimed at developing a Setswana grammar checker for Setswana declarative sentences using Long Short-Term Memory Recurrent neural networks (LSTM-RNNs). The research was motivated by the fact that Setswana is recognized as one of the under-resourced languages in the world and the language lacks Natural language processing (NLP) tools such as grammar checkers; this delays the language’s technological progress. A Setswana grammar checker is a pre-requisite to th...
Abstract: The presence of harmonics in solar Photo Voltaic (PV) energy conversion system results in deterioration of power quality. To address such issue, this paper aims to investigate the elimination of harmonics in a solar fed cascaded fifteen level inverter with aid of Proportional Integral (PI), Artificial Neural Network (ANN) and Fuzzy Logic (FL) based controllers. Unlike other techniques, the proposed FLC based approach helps in obtaining reduced harmonic distortions that intend to an...
Abstract: It is anticipated that laser cladding assisted with preheat (LCAP)-deposited Tribaloy (T-800) composite coatings enhances resistance to structural degradation upon exposure to elevated-temperature oxidation service environments. The oxidation kinetics of LCAP T-800 composite coatings deposited on EN8 substrate and its mechanisms have not been explored in severe conditions that are similar to operational parameters. The isothermal oxidation behaviour of the T-800 composite coating d...
Abstract: Fossil fuels, particularly crude oil, have proven to be a source of energy to households, transportation and power industries over the past decades. This natural reserve is diminishing at an alarming rate with crude oil having reserves to last the earth for the next half a century. As a result, researchers are constantly seeking remedial technologies to close this gap. Thermochemical conversion processes such as pyrolysis, gasification and liquefaction (PGL) offer an alternative so...
Abstract: Al2O3.TiO2 ceramic composites exhibit versatile properties such as high hardness and excellent wear, chemical, thermal and corrosion resistance. As such, they have been used in various applications such as optical and electronic, gas separation, biomedical processes, and support for transition metal catalysts, wear resistant coatings in machinery, textile and printing industries. However, alumina and alumina-based composites often exhibit high brittleness which limits their potenti...
Abstract: Coal due to its relatively large quantities and wide distribution worldwide has generated renewed interest in research and development with the aim of establishing coal conversion technologies that are technically reliable, environmentally and economically feasible. It has proved to be a prominent energy source in emerging markets with increasing energy demand by accounting for the largest increase in the demand of energy amongst all other energy sources. Furthermore, with its high...
Abstract: Before disposal of any metallurgical waste to the environment, it is the responsibility of mining institutes to adhere to the permissible metal content limits. Base metals, especially iron and copper, have adverse effects of reducing the soil pH and excessive concentrations of these in the disposed waste may result in soil pollution and toxicity, with adverse effects on plant growth and animal health. Copper slag is a metallurgical waste that is disposed by way of stockpiling at de...
Abstract: The research presents a comparative study on the effectiveness of blending plant based natural coagulants (Cactus Opuntia and Moringa Oleifera extracts) and a synthetic coagulant (aluminium sulphate or alum) in treatment of raw water. The low production rates of natural coagulants has derailed their commercialization this has driven the idea of blending synthetic coagulants which is envisaged to be the more appropriate means of application in this study. To measure the effectivenes...
Abstract: In this review, the role of surface modification of nanoparticles to enhance their performance as adsorbents was explored. Performance was assessed by comparisons on adsorption capacities of differently modified nanoparticles (silica, iron, and alumina based nanoparticles) on different heavy metal ions (Cu, Cd, Co, Ni, Pb, As, Cr, Zn, Mn, and Hg). A comparison of pure and modified materials revealed that the modified materials gave superior adsorption capacities. A close relationsh...
Abstract: The disposal of sludge processes accounts for 60% of the total operation and 40% of total emissions of greenhouse gas from wastewater treatment plants operations. Moreover, sludge contains pathogenic microorganisms, organics, inorganics, trace metals and emerging micropollutants, which can be a public health menace. To comply with the Environmental Protection Agency standards, sludge must be stabilized and detoxified before being disposed or reused. This study focuses on the use of...
Abstract: Surface structure determines the performance of materials in service. Enhancing the surface topography of materials with a refractory ceramic coating such as Titanium carbide has gained unprecedented development of recent due to the increase in applications of these functionally graded materials. Radio frequency (RF) magnetron sputtering exhibits a lot of potential in depositing and growing thin film thin. One of the major advantages of RF magnetron sputtering is the ability to be ...
Abstract: In this article, alternative forms of optimizing the milling efficiency of a laboratory scale ball mill by varying the grinding media size distribution and the feed material particle size distribution were investigated. Silica ore was used as the test material. The experimental parameters that were kept constant in this investigation was the grinding media filling, powder filling and the mill rotational speed. The data obtained from these batch tests was then analyzed using a model...
Abstract: The mobile demands and future business context are anticipated to be resolved by the fifth-generation (5G) of mobile communication systems. It is expected to provide an utterly mobile device, connected society, and support the demanding services of various use cases (UCs). This is intended to meet the demand requirement by providing services at tens of Gbps in terms of data rates, higher mobility range, lower latencies, and massive connectivity density devices per square kilometer....
Abstract: In this work, a small activation chamber was specially designed to facilitate the irradiation of selected samples with secondary neutrons behind a radionuclide production target in the vertical-beam target station (VBTS) at iThemba LABS. The main aim was to assay the radionuclides formed in the samples, with a special interest in those of medical importance. The experiment was performed simultaneously with a routine radionuclide production run, during which the target was bombarded...
Abstract: Long Range (LoRa) is a leading low power wide area network under the IEEE802.15.4 designation. The technology has been used extensively in wireless sensor network applications (WSN) and studies are shifting to investigate the technology’s viability when used for navigation. However, the problem of planning and deployment of LoRa in navigation as well as the repeatable accuracy of such a system based on known timing errors has not been done. The first chapter of this thesis prese...