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...
Abstract: The field of microelectronics experienced a huge shift from the traditional planar MOSFET to 3D multi-gated structures, most noticeable being the FinFET. FinFET is regarded the most favourable for progressing CMOS downscalling in the nanometer scale due to its ability to suppress short channel effects due to its better gate control, enabling it to achieve performance of high quality and low power. The fin dimen sions play a huge role in the design of a FinFET. Looking at the gadget...
Abstract: Due to human influence and its negative impacts on the world’s environment, the world ischanging into a cleaner and more sustainable energy system. In both private and public buildings, there isa desire to reduce electricity usage, automate appliances, and optimize the electricity usage of a building.This paper presents the design and implementation of a secured smart home switching system based onwireless communications and self-energy harvesting. The proposed secured smart home...
Abstract: This study describes a DC to DC voltage multiplier using the 555 Integrated Circuit (IC) timer in an astable state. The major motivation of the design is to be able to produce an inexpensive and light form of generating high DC voltage to power devises that would normal need a really large and heavy battery to be operated. The study also briefly touch on the negative aspects of large DC voltage, heat dissipation and general battery life. With the help of the astable state of the mu...
Abstract: This paper presents the design and simulation of an Automatic Room Heater Control system. This system allows the user to set a desired temperature which is then compared to the room temperature measured by a temperature sensor.With the help of a micro controller, the system responds by turning ON any of the two (2) loads (Fan or a heater) automatically depending on the temperature difference. The Fan is triggered ON when the room temperature is higher than the set temperature and t...
Abstract: Improving Available Transfer Capability is an important issue in the deregulated power systems. The Available Transfer Capability of a transmission network is the transfer capabilities of a transmission network for the transfer of power for further commercial activity, over and above already committed usage. It is a proven fact that Flexible Alternating Current Transmission System technology can control voltage magnitude, phase angle, and circuit reactance. Therefore, it is importa...
Abstract: The reactive power compensation in power system is done by using different Flexible AC Transmission Controllers (FACTS). Unified Power Flow Controller (UPFC) is simulated and analyzed to observe its overall functions when integrated into a transmission line. It is installed in electric transmission lines hence assisting in the controlling and manipulating of the power flowing in the lines to give out reliable, controlled and efficient electricity to an ordinary consumer. The modell...
Abstract: Global Navigation Satellite System Reflectometry (GNSSR) can be used to derive information about the composition or the properties of ground surfaces, by analyzing signals emitted by GNSS satellites and reflected from the ground. If the received power is measured with linearly polarized antennas, under the condition of smooth surface, the reflected signal is proportional to the modulus of the perpendicular and parallel polarization Fresnel coefficients, which depend on the incidenc...
Abstract: The use of the millimeter wave (mmWave) spectrum and further exploration of sub mmWave has led to a new era in wireless communication, as the need for higher data rates grows. High frequencies, on one hand, incur a higher path loss, requiring an increase in antenna gain requirements. Metasurfaces, which emerge as a promising technology for mitigating path loss effects by utilizing 2D arrays of engineered meta-atoms resembling metamaterials that control the surface’s electromagnet...
Abstract: Amidst escalating data traffic demands, the fifth generation (5G) of mobile communication has been launched to curb these demands by providing high data rates, decreased latency, increased network capacity and large bandwidth. The ambitious performance expected from the 5G cellular communication network is enabled by different key technologies including shifting towards the millimeter wave frequency band. However, the millimeter wave band is accompanied by limitations of signal pat...
Abstract: This paper presents the design and implementation of Modular Multilevel Inverter (MMI) to control the Induction Motor (IM) drive using intelligent techniques towards marine water pumping applications. The proposed inverter is of eleven levels and has the ability to control the speed of an IM drive which is fed from solar photovoltaics. It is estimated that the energy consumed by pumping schemes in an onboard ship is nearly 50% of the total energy. Considering this fact, this paper ...
Abstract: This paper reports the experimental investigation of the corona discharge activity of punga oil under the influence of a local magnetic field and different voltage profiles (AC and DC voltages) using fluorescent fiber sensor as well as UHF sensor technique. The corona inception voltage (CIV) of punga oil is higher under negative DC voltage followed by positive DC and AC voltage, with a marginal reduction in its CIV magnitude observed on the impact of external magnetic field. The do...
Abstract: In visible light communication(VLC),arrays consisting of a single or multi-colour light sources are employed for a dual purpose being: the provision of illumination and data transmission. Therefore, it is substantial to come up with efficient techniques for resource allocation. The aim of this thesis is to design and develop a multi-user colour-based optical spatial modulation VLC framework using a line-of-sight (LoS) model. An optimisation problem with the intention of minimising...
Abstract: Solar energy is an abundant and clean resource. However, solar energy applications face challenges of low efficiency and high capital investments. To mitigate low efficiencies, electro-mechanical trackers that follow the sun path to enhance reception of solar energy are used. Usually these devices are complex in design. In this study, a simpler and less energy consuming dual axis solar tracker concept is designed and evaluated. A design process model consisting of the three main ph...