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Ladysmith is a major economic hub in the uThukela District Municipality. However, it has been experiencing floods almost every year which has resulted in the loss of lives and disruption of business activity within the Ladysmith Central Business District. The main objective of this study was to quantify the land use/cover changes before and after…

In devices using Windows operating system based on x86 system, the real-time performance is not guaranteed by Windows. It is because Windows is not a real-time operating system. Users who develop applications in such a Windows environment generally use commercial solutions such as the RTX or the INtime to provide real-time performance to the system.…

To effectively implement the social distancing or digital contact tracing in epidemic using an RSSI-based localization approach through Bluetooth beacon is one of the most widely used technologies, but simply using RSSI measurement is not more relevant because the RF signal is affected by several factors and the environment of usage. Traditional distance or positioning…

This paper presents the designs and the simulations of proposed structures of electronically frequency reconfigurable planar bow-tie antenna. In the first part, a modified wide band self-complementary bow-tie antenna is designed and implemented. In the second part, varactor and PIN diodes are integrated in top side to adjust electronically the modified structure of bow-tie antenna…

In this investigation, an integrated physics-informed deep learning and topology optimization approach for solving density-based topology designs is presented to accomplish efficiency and flexibility. In every iteration, the neural network generates feasible topology designs, and then the topology performance is evaluated using the finite element method. Unlike the data-driven methods where the loss functions are…

Transformers are habitually designed and manufactured for operation at a fundamental frequency of 50Hz and sinusoidal load current. Transformers are susceptible to non-linear loads. The inception of switching action characterises Non-linear loads and consequently nonsinusoidal load current which brings about higher transformer service losses, hotspot temperature rise, and degradation of cellulosic and liquid insulation, and…

Classical clustering algorithms often require an a-priori number of expected clusters and the presence of all documents beforehand. From practical point of view, the use of these algorithms especially in more dynamic environments dealing with growing or shrinking corpora therefore is not applicable. Within the last years, graph-based representations of knowledge such as co-occurrence graphs…

The Present work is to investigate effect of dry sliding wear behaviour of ZA27 base alloy, after reinforcing it with Molybdenum Di Sulphide (MoS2) particles from 0% to 4% in five steps. To examine the wear behaviour of both reinforced and un-reinforced material, dry or unlubricated pin on disc tests were conducted. These tests were…

Distributed Solar Photovoltaic (DSP) Plants are one of the fastest growing renewable energy systems in South Africa. The primary components forming an integral part of the point of common coupling (PCC) are, the inverter used to convert dc voltage to ac voltage and step-up transformers which step-up low voltage input to the desired output level.…

A new approach for designing RF energy harvester with a single stage converter circuit is presented in this paper. The proposed converter configuration is integrated with an antenna that is based on the coplanar waveguide (CPW) transmission line with improved gain resonated at 2.45 frequency ISM band. The CPW patch antenna as a harvester antenna…

Depth prediction plays a key role in understanding a 3D scene. Several techniques have been developed throughout the years, among which Convolutional Neural Network has recently achieved state-of-the-art performance on estimating depth from a single image. However, traditional CNNs suffer from the lower resolution and information loss caused by the pooling layers. And oversized parameters…

The ecosystems and landscape patterns in Lake Victoria basin are increasingly being modified by changes in land use/land cover. Understanding dynamics of these changes is essential for appropriate planning. This study evaluated changes in landscape environment, of the lakeside counties of the Kenyan Lake Victoria basin, which have occurred over a forty-year period (1978-2018) and…

To this extent, the delineation of techno-economic evaluations for transformers becomes more intricate through a lens of Distributed Solar Photovoltaic (DSPV) market in South Africa. Essentially, the transformer price and loss evaluation techniques should be tailored for calculating the Total Ownership Cost (TOC) of transformers facilitating decentralized energy systems. In South Africa, the traditional coal…

Integration of Distributed Generation (DG) on distribution networks has a positive impact which includes the following: low power losses, improved utility system reliability and voltage improvement at buses. A real distribution network is radial in which energy flow is unidirectional from generation to transmission and from distribution to the load. However, when a DG is…

The optimum performance of power plants has major technical and economic benefits. A case study in one of the Malaysian power plants reveals an escalating harmonic failure trend in their Continuous Ship Unloader (CSU) machines. This has led to a harmonic filter failure causing performance loss leading to costly interventions and safety concerns. Analysis of…

Higher efficiency and lower losses are widely considered as the best metrics to optimize, in a high-power converter performance context. To provide a solution to the ever-increase of high switching frequencies challenges, we must explore soft-switching technologies to resolve interface issues and reduce the switching losses. This manuscript describes a comparative analysis between the fixed-bandwidth…

In this paper, we investigate and analyze parameters degradation in a typical photovoltaic (PV) cell, which lead to power loss under dark as well as light condition using measured current-voltage (I-V) data. A nonlinear least squares method to extract the parameters such as the reverse saturation currents, the ideality factors, the series and shunt resistances…

The article presents some results of the research of the LoRa module. These modules can be the basis of possible IoT technologies are implementing, providing enough good range of receiving and transmitting messages. The SX1276 transceiver has been testing to determine the signal loss in the propagation channel. These experiments took in a highly-populated Kyiv…

The angle of attack is a critical flight parameter for commercial aviation aircraft, because automatic envelope protection systems rely on it to keep the aircraft within its safe flight envelope. Faulty measurements of the angle of attack could have catastrophic effects, leading to aircraft loss of control in flight and fatalities, as demonstrated by the…

The paper treats a problem for detection and recognition objects in computer vision sector, where researchers recommended OpenCV software and development tool, it’s several and better-remembered library resource for isolating, detecting, and recognition of particular objects, what we would find an appropriate system for detecting and recognition traffic roads signs. The robustness with optimization is…

The article describes the concept and architecture of a decentralized control system for a solid-state voltage regulator (SSVR). The SSVR is a universal device for controlling the mode and operation parameters of medium voltage electrical networks. SSVR manage the amount of current in line using the vector voltage control method. The SSVR control system consists…

In this study, we study on the downlink indoor coverage performance of unmanned air vehicle (UAV) base stations. We consider a probabilistic expression for air-to-ground (ATG) path loss, and a deterministic one for additional indoor losses in order to provide a practical model. One of our important assumptions is that the UAV base station operates…

Growing adoption of cryptocurrencies by institutional investors coupled with recurring incidents of loss of access to digital wallets have resulted in emergence of custodial services for high net worth individuals and institutions. However, such services are not economically feasible for the wider community of crypto owners who are left with no recourse for recovery of…

The pressing and most urgent challenge for most of the Posts in Southern Africa is to transit from its historical reputation of being a snail-paced, inefficient, loss-making and ineffective service provider to an agile, innovative, solution-driven and highly competitive service provider that strive for excellence. In this context, adoption, and diffusion of technology and digital…

This paper presents the results of the research conducted with the help of cognitive cybernetics about the “mass” factor from the theory of totalitarianism. According to the expert system model, “big data” analysis sought to discover knowledge for assessing the future status of digital social connectivity. Originally developed models and methods of cognitive and computer…