This research is focused on the acquisition of electronic safety equipment for mines and was conducted within the design science research (DSR) framework. Design science research ensured a directed research process was followed. The existing acquisition process and risk management methods used in the South African mining environment were analysed by means of observations, a case study, technical documentation and literature. It was evident from this analysis that a discontinuity existed between the acquisition and operations phases in terms of the management of safety risk in the acquisition of electronic safety equipment when viewed from a full life cycle perspective. This discontinuity could be addressed by defining a risk perspective on acquisition, as such a perspective would draw together engineering and mining operations in terms of safety and productivity. Research topics in this literature study include risk definition and terminologies, risk management frameworks, risk analysis methodologies and characterization, existing risk assessment tools and techniques, human error and operational modelling, and systems engineering. A literature study showed that similar challenges existed in other disciplines, with proposed solutions, but the discontinuity between the acquisition and operational phases had not been addressed. A specific approach of this research was to derive individualised research challenges aligned with the main research challenge, and then to translate each research challenge into one or more research solutions. The discontinuity between the acquisition and operational phases (engineering and mining) is addressed by an activity-based risk (ABR) acquisition process. The activity-based risk method forms part of preliminary design of a systems engineering life cycle, as this phase is of critical importance to the ABR acquisition process. The focus of the ABR acquisition process is to find the functional definition and configuration of safety equipment that addresses both safety and productivity when taking into account human performance variability. In doing so, a balance between productivity and safety is found in a relativistic sense. The effectiveness of the ABR process was verified in a real-world case study, where a safety system was analysed, fully developed, and evaluated in an operational environment to address safety risks associated with winch scraper operations. Characteristics of the ABR process were demonstrated in this case study, which also showed in detail how to develop risk- and cost-reduced equipment from a risk perspective. Feedback obtained from evaluation of the resulting safety equipment in operation was found to be consistent with the ABR model simulation results, and assisted with the validation of the winch signalling system operational model. Details of the ABR acquisition process are presented for functional analyses, simulation model construction, human performance variability modelling, risk-related performance measurement, simulation model evaluation, trade-off analyses, and physical realisation of winch signalling system artefacts. Finally, the advantages of using an ABR acquisition process are shown to underline the effectiveness of using a risk perspective for the acquisition of electronic safety equipment on South African mines. / PhD (Development and Management Engineering), North-West University, Potchefstroom Campus, 2015

This research is focused on the acquisition of electronic safety equipment for mines and was conducted within the design science research (DSR) framework. Design science research ensured a directed research process was followed. The existing acquisition process and risk management methods used in the South African mining environment were analysed by means of observations, a case study, technical documentation and literature. It was evident from this analysis that a discontinuity existed between the acquisition and operations phases in terms of the management of safety risk in the acquisition of electronic safety equipment when viewed from a full life cycle perspective. This discontinuity could be addressed by defining a risk perspective on acquisition, as such a perspective would draw together engineering and mining operations in terms of safety and productivity. Research topics in this literature study include risk definition and terminologies, risk management frameworks, risk analysis methodologies and characterization, existing risk assessment tools and techniques, human error and operational modelling, and systems engineering. A literature study showed that similar challenges existed in other disciplines, with proposed solutions, but the discontinuity between the acquisition and operational phases had not been addressed. A specific approach of this research was to derive individualised research challenges aligned with the main research challenge, and then to translate each research challenge into one or more research solutions. The discontinuity between the acquisition and operational phases (engineering and mining) is addressed by an activity-based risk (ABR) acquisition process. The activity-based risk method forms part of preliminary design of a systems engineering life cycle, as this phase is of critical importance to the ABR acquisition process. The focus of the ABR acquisition process is to find the functional definition and configuration of safety equipment that addresses both safety and productivity when taking into account human performance variability. In doing so, a balance between productivity and safety is found in a relativistic sense. The effectiveness of the ABR process was verified in a real-world case study, where a safety system was analysed, fully developed, and evaluated in an operational environment to address safety risks associated with winch scraper operations. Characteristics of the ABR process were demonstrated in this case study, which also showed in detail how to develop risk- and cost-reduced equipment from a risk perspective. Feedback obtained from evaluation of the resulting safety equipment in operation was found to be consistent with the ABR model simulation results, and assisted with the validation of the winch signalling system operational model. Details of the ABR acquisition process are presented for functional analyses, simulation model construction, human performance variability modelling, risk-related performance measurement, simulation model evaluation, trade-off analyses, and physical realisation of winch signalling system artefacts. Finally, the advantages of using an ABR acquisition process are shown to underline the effectiveness of using a risk perspective for the acquisition of electronic safety equipment on South African mines. / PhD (Development and Management Engineering), North-West University, Potchefstroom Campus, 2015

Informed economic decisions are made on the basis of accounting data. It is therefore crucial to have rigorous and scientific approaches for measuring, modelling and forecasting accounting numbers. Dr Falta's research was motivated by two observations. Firstly, in accounting practice, decision-making often relies on subjective quantifications and forecasts of business activities and, thus, does not account for uncertainty in a rational way. Secondly, there are some academic foundations for statistical approaches to accounting, yet none has been developed carefully enough for results to penetrate and to contribute to practitioners' needs. Dr Falta applied components of mathematics, statistics, econometrics, finance and computing to aspects of accounting and auditing. He developed an enhanced framework for scientific measurement of business process costing and recording accounting transaction data. This has enabled a better understanding of risk in accounting-based decision-making. His research is being incorporated in projects with the Royal Australian Navy and SunWater.