No abstract available / Dissertation (MA)--University of Pretoria, 1963. / gm2013 / Psychology / unrestricted

The global energy sector is facing a crisis caused by the increasing demand for energy. Non-renewable energy sources, such as fossil fuels produce greenhouse gases that are largely blamed for climate change. The Kyoto protocol requires industrialised nations to reduce their collective greenhouse gas emissions. Hydrogen as an alternative fuel can serve as a substitute. Hydrogen production is expensive and the gas is largely derived from fossil fuels by a process that releases large quantities of greenhouse gases. In South Africa work on hydrogen production was first done on the Hybrid Sulphur cycle. The high operating temperature and highly corrosive environment involved in the process makes this cycle difficult to work with. The copper-chloride cycle has a lower operating temperature and uses less corrosive materials, making the cycle potentially more economical. Evaluation of the cycle started with the development of four models: the Base model, the Canadian model (developed in Canada) the Kemp model and the Excess model. The Kemp model has the best overall efficiency of 40.89 %, producing hydrogen at a cost of US$4.48/kg. The model does not however provide the excess steam required for the cycle. The Excess model which is based on the Kemp model does provide the excess steam and produces an overall efficiency of 39 % and hydrogen at a cost of US$4.60/kg. The copper-chloride cycle has an improved efficiency and produces hydrogen at a lower cost when compared to the hybrid sulphur cycle. The final conclusion of this thesis is that the copper-chloride cycle should be investigated further and an expected capital and operational costs estimate should be developed to obtain more accurate figures. / Thesis (M.Ing. (Nuclear Engineering))--North-West University, Potchefstroom Campus, 2012.

The global energy sector is facing a crisis caused by the increasing demand for energy. Non-renewable energy sources, such as fossil fuels produce greenhouse gases that are largely blamed for climate change. The Kyoto protocol requires industrialised nations to reduce their collective greenhouse gas emissions. Hydrogen as an alternative fuel can serve as a substitute. Hydrogen production is expensive and the gas is largely derived from fossil fuels by a process that releases large quantities of greenhouse gases. In South Africa work on hydrogen production was first done on the Hybrid Sulphur cycle. The high operating temperature and highly corrosive environment involved in the process makes this cycle difficult to work with. The copper-chloride cycle has a lower operating temperature and uses less corrosive materials, making the cycle potentially more economical. Evaluation of the cycle started with the development of four models: the Base model, the Canadian model (developed in Canada) the Kemp model and the Excess model. The Kemp model has the best overall efficiency of 40.89 %, producing hydrogen at a cost of US$4.48/kg. The model does not however provide the excess steam required for the cycle. The Excess model which is based on the Kemp model does provide the excess steam and produces an overall efficiency of 39 % and hydrogen at a cost of US$4.60/kg. The copper-chloride cycle has an improved efficiency and produces hydrogen at a lower cost when compared to the hybrid sulphur cycle. The final conclusion of this thesis is that the copper-chloride cycle should be investigated further and an expected capital and operational costs estimate should be developed to obtain more accurate figures. / Thesis (M.Ing. (Nuclear Engineering))--North-West University, Potchefstroom Campus, 2012.

The Constitution of the Republic of South Africa 108 of 1996 (SA, 1996) makes provision for all citizens to receive quality health care. Legislation such as the White Paper on the Transformation of the Public Service of 1995, (SA, 1995a), the White Paper on Transforming Public Service Delivery (Batho Pele) (SA, 1997b), the Public Service Act 103 of 1994, as amended (SA, 1994), the Labour Relations Act 66 of 1995 (SA, 1995b) and the Employment Equity Act 55 of 1998 (SA, 1998) enshrines this right for all citizens by ensuring that health authorities put measures in place to improve the performance of nurse employee (NE), and thus ensuring quality health care. NE are only able to improve the quality of their performance, if their performance is systematically appraised and their potential for development is identified. However, researchers, for instance Du Plessis (2002:116), Nkosi (2002:37–44), Narcisse and Harcourt (2008:1154), Thompson et al. (1999:139), Fletcher (2001:473) studied the perceptions and experiences of employees and managers of performance appraisal (PA) and these studies indicated that there is a gap in the implementation of PA. The Performance Management and Development System (PMDS) policy (Policy no. NWPG 13) was implemented in the North West public health sector in clinics and hospitals in 2004 to provide guidelines for the implementation of PA. This policy is reviewed annually since it was first drafted. However the researcher’s personal experience with PA in practice was that there is a gap between the process provided by the PMDS policy (Policy no. NWPG 13) and the implementation thereof in the North West public health sector. This led to the following research questions: how is PA implemented from the perspectives of nurse line managers (NLM) and NE in clinics in the Dr Kenneth Kaunda District (KKD) and what guidelines can be developed to improve the implementation of PA in clinics in the KKD? The study aimed to develop guidelines to improve the implementation of PA in clinics in the KKD. The study had a cross–sectional quantitative design with exploratory, descriptive and contextual research strategies. Two questionnaires: one for NLM and the other for NE were developed from section 13.4.4 and 13.4.5 of the PMDS policy (Policy no. NWPG 13 amendment approved for 2008–2009 performance cycle) (SA, 2007), to explore and describe the perceptions of NLM and NE on the implementation of PA in clinics in the KKD. Twenty–three problems were identified from the empirical research with regard to communication, feedback and participation in PA, which served as the evidence base towards developing guidelines to improve the implementation of PA in clinics in the KKD. The guidelines were developed using inductive and deductive reasoning and were based on the ten–point plan of Juran. Finally the research was evaluated, limitations were identified and recommendations were formulated for practice, education, management, research and policy. / Thesis (M.Cur.)--North-West University, Potchefstroom Campus, 2012.

The Constitution of the Republic of South Africa 108 of 1996 (SA, 1996) makes provision for all citizens to receive quality health care. Legislation such as the White Paper on the Transformation of the Public Service of 1995, (SA, 1995a), the White Paper on Transforming Public Service Delivery (Batho Pele) (SA, 1997b), the Public Service Act 103 of 1994, as amended (SA, 1994), the Labour Relations Act 66 of 1995 (SA, 1995b) and the Employment Equity Act 55 of 1998 (SA, 1998) enshrines this right for all citizens by ensuring that health authorities put measures in place to improve the performance of nurse employee (NE), and thus ensuring quality health care. NE are only able to improve the quality of their performance, if their performance is systematically appraised and their potential for development is identified. However, researchers, for instance Du Plessis (2002:116), Nkosi (2002:37–44), Narcisse and Harcourt (2008:1154), Thompson et al. (1999:139), Fletcher (2001:473) studied the perceptions and experiences of employees and managers of performance appraisal (PA) and these studies indicated that there is a gap in the implementation of PA. The Performance Management and Development System (PMDS) policy (Policy no. NWPG 13) was implemented in the North West public health sector in clinics and hospitals in 2004 to provide guidelines for the implementation of PA. This policy is reviewed annually since it was first drafted. However the researcher’s personal experience with PA in practice was that there is a gap between the process provided by the PMDS policy (Policy no. NWPG 13) and the implementation thereof in the North West public health sector. This led to the following research questions: how is PA implemented from the perspectives of nurse line managers (NLM) and NE in clinics in the Dr Kenneth Kaunda District (KKD) and what guidelines can be developed to improve the implementation of PA in clinics in the KKD? The study aimed to develop guidelines to improve the implementation of PA in clinics in the KKD. The study had a cross–sectional quantitative design with exploratory, descriptive and contextual research strategies. Two questionnaires: one for NLM and the other for NE were developed from section 13.4.4 and 13.4.5 of the PMDS policy (Policy no. NWPG 13 amendment approved for 2008–2009 performance cycle) (SA, 2007), to explore and describe the perceptions of NLM and NE on the implementation of PA in clinics in the KKD. Twenty–three problems were identified from the empirical research with regard to communication, feedback and participation in PA, which served as the evidence base towards developing guidelines to improve the implementation of PA in clinics in the KKD. The guidelines were developed using inductive and deductive reasoning and were based on the ten–point plan of Juran. Finally the research was evaluated, limitations were identified and recommendations were formulated for practice, education, management, research and policy. / Thesis (M.Cur.)--North-West University, Potchefstroom Campus, 2012.

In this thesis, ammonia (NH3) decomposition was assessed as a fuel processing technology for producing on-demand hydrogen (H2) for portable and distributed fuel cell applications. This study was motivated by the present lack of infrastructure to generate H2 for proton exchange membrane (PEM) fuel cells. An overview of past and recent worldwide research activities in the development of reactor technologies for portable and distributed hydrogen generation via NH3 decomposition was presented in Chapter 2. The objective was to uncover the principal challenges relating to the state-of-the-art in reactor technology and obtain a basis for future improvements. Several important aspects such as reactor design, operability, power generation capacity and efficiency (conversion and energy) were appraised for innovative reactor technologies vis-à-vis microreactors, monolithic reactors, membrane reactors, and electrochemical reactors (electrolyzers). It was observed that substantial research effort is required to progress the innovative reactors to commercialization on a wide basis. The use of integrated experimental-mathematical modelling approach (useful in attaining accurately optimized designs) was notably non-existent for all reactors throughout the surveyed openliterature. Microchannel reactors were however identified as a transformative reactor technology for producing on-demand H2 for PEM cell applications. Against this background, miniaturized H2 production in a stand-alone ammonia-fuelled microchannel reactor (reformer) washcoated with a commercial Ni-Pt/Al2O3 catalyst (ActiSorb® O6) was demonstrated successfully in Chapter 3. The reformer performance was evaluated by investigating the effect of reaction temperature (450–700 °C) and gas-hourly-space-velocity (6 520–32 600 Nml gcat -1 h-1) on key performance parameters including NH3 conversion, residual NH3 concentration, H2 production rate, and pressure drop. Particular attention was devoted to defining operating conditions that minimised residual NH3 in reformate gas, while producing H2 at a satisfactory rate. The reformer operated in a daily start-up and shut-down (DSS)-like mode for a total 750 h comprising of 125 cycles, all to mimic frequent intermittent operation envisaged for fuel cell systems. The reformer exhibited remarkable operation demonstrating 98.7% NH3 conversion at 32 600 Nml gcat -1 h-1 and 700 °C to generate an estimated fuel cell power output of 5.7 We and power density of 16 kWe L-1 (based on effective reactor volume). At the same time, reformer operation yielded low pressure drop (<10 Pa mm-1) for all conditions considered. Overall, the microchannel reformer performed sufficiently exceptional to warrant serious consideration in supplying H2 to low-power fuel cell systems. In Chapter 4, hydrogen production from the Ni-Pt-washcoated ammonia-fuelled microchannel reactor was mathematically simulated in a three-dimensional (3D) CFD model implemented via Comsol Multiphysics™. The objective was to obtain an understanding of reaction-coupled transport phenomena as well as a fundamental explanation of the observed microchannel reactor performance. The transport processes and reactor performance were elucidated in terms of velocity, temperature, and species concentration distributions, as well as local reaction rate and NH3 conversion profiles. The baseline case was first investigated to comprehend the behavior of the microchannel reactor, then microstructural design and operating parameters were methodically altered around the baseline conditions to explore the optimum values (case-study optimization). The modelling results revealed that an optimum NH3 space velocity (GHSV) of 65.2 Nl gcat -1 h-1 yields 99.1% NH3 conversion and a power density of 32 kWe L-1 at the highest operating temperature of 973 K. It was also shown that a 40-μm-thick porous washcoat was most desirable at these conditions. Finally, a low channel hydraulic diameter (225 μm) was observed to contribute to high NH3 conversion. Most importantly, mass transport limitations in the porouswashcoat and gas-phase were found to be negligible as depicted by the Damköhler and Fourier numbers, respectively. The experimental microchannel reactor produced 98.2% NH3 conversion and a power density of 30.8 kWe L-1 when tested at the optimum operating conditions established by the model. Good agreement with experimental data was observed, so the integrated experimental-modeling approach used here may well provide an incisive step toward the efficient design of ammonia-fuelled microchannel reformers. In Chapter 5, the prospect of producing H2 via ammonia (NH3) decomposition was evaluated in an experimental stand-alone microchannel reactor wash-coated with a commercial Cs-promoted Ru/Al2O3 catalyst (ACTA Hypermec 10010). The reactor performance was investigated under atmospheric pressure as a function of reaction temperature (723–873 K) and gas-hourly-space-velocity (65.2–326.1 Nl gcat -1 h-1). Ammonia conversion of 99.8% was demonstrated at 326.1 Nl gcat -1 h-1 and 873 K. The H2 produced at this operating condition was sufficient to yield an estimated fuel cell power output of 60 We and power density of 164 kWe L-1. Overall, the Ru-based microchannel reactor outperformed other NH3 microstructured reformers reported in literature including the Ni-based system used in Chapter 3. Furthermore, the microchannel reactor showed a superior performance against a fixed-bed tubular microreactor with the same Ru-based catalyst. Overall, the high H2 throughput exhibited may promote widespread use of the Ru-based micro-reaction system in high-power applications. Four peer-reviewed journal publications and six conference publications resulted from this work. / PhD (Chemical Engineering), North-West University, Potchefstroom Campus, 2015

In this thesis, ammonia (NH3) decomposition was assessed as a fuel processing technology for producing on-demand hydrogen (H2) for portable and distributed fuel cell applications. This study was motivated by the present lack of infrastructure to generate H2 for proton exchange membrane (PEM) fuel cells. An overview of past and recent worldwide research activities in the development of reactor technologies for portable and distributed hydrogen generation via NH3 decomposition was presented in Chapter 2. The objective was to uncover the principal challenges relating to the state-of-the-art in reactor technology and obtain a basis for future improvements. Several important aspects such as reactor design, operability, power generation capacity and efficiency (conversion and energy) were appraised for innovative reactor technologies vis-à-vis microreactors, monolithic reactors, membrane reactors, and electrochemical reactors (electrolyzers). It was observed that substantial research effort is required to progress the innovative reactors to commercialization on a wide basis. The use of integrated experimental-mathematical modelling approach (useful in attaining accurately optimized designs) was notably non-existent for all reactors throughout the surveyed openliterature. Microchannel reactors were however identified as a transformative reactor technology for producing on-demand H2 for PEM cell applications. Against this background, miniaturized H2 production in a stand-alone ammonia-fuelled microchannel reactor (reformer) washcoated with a commercial Ni-Pt/Al2O3 catalyst (ActiSorb® O6) was demonstrated successfully in Chapter 3. The reformer performance was evaluated by investigating the effect of reaction temperature (450–700 °C) and gas-hourly-space-velocity (6 520–32 600 Nml gcat -1 h-1) on key performance parameters including NH3 conversion, residual NH3 concentration, H2 production rate, and pressure drop. Particular attention was devoted to defining operating conditions that minimised residual NH3 in reformate gas, while producing H2 at a satisfactory rate. The reformer operated in a daily start-up and shut-down (DSS)-like mode for a total 750 h comprising of 125 cycles, all to mimic frequent intermittent operation envisaged for fuel cell systems. The reformer exhibited remarkable operation demonstrating 98.7% NH3 conversion at 32 600 Nml gcat -1 h-1 and 700 °C to generate an estimated fuel cell power output of 5.7 We and power density of 16 kWe L-1 (based on effective reactor volume). At the same time, reformer operation yielded low pressure drop (<10 Pa mm-1) for all conditions considered. Overall, the microchannel reformer performed sufficiently exceptional to warrant serious consideration in supplying H2 to low-power fuel cell systems. In Chapter 4, hydrogen production from the Ni-Pt-washcoated ammonia-fuelled microchannel reactor was mathematically simulated in a three-dimensional (3D) CFD model implemented via Comsol Multiphysics™. The objective was to obtain an understanding of reaction-coupled transport phenomena as well as a fundamental explanation of the observed microchannel reactor performance. The transport processes and reactor performance were elucidated in terms of velocity, temperature, and species concentration distributions, as well as local reaction rate and NH3 conversion profiles. The baseline case was first investigated to comprehend the behavior of the microchannel reactor, then microstructural design and operating parameters were methodically altered around the baseline conditions to explore the optimum values (case-study optimization). The modelling results revealed that an optimum NH3 space velocity (GHSV) of 65.2 Nl gcat -1 h-1 yields 99.1% NH3 conversion and a power density of 32 kWe L-1 at the highest operating temperature of 973 K. It was also shown that a 40-μm-thick porous washcoat was most desirable at these conditions. Finally, a low channel hydraulic diameter (225 μm) was observed to contribute to high NH3 conversion. Most importantly, mass transport limitations in the porouswashcoat and gas-phase were found to be negligible as depicted by the Damköhler and Fourier numbers, respectively. The experimental microchannel reactor produced 98.2% NH3 conversion and a power density of 30.8 kWe L-1 when tested at the optimum operating conditions established by the model. Good agreement with experimental data was observed, so the integrated experimental-modeling approach used here may well provide an incisive step toward the efficient design of ammonia-fuelled microchannel reformers. In Chapter 5, the prospect of producing H2 via ammonia (NH3) decomposition was evaluated in an experimental stand-alone microchannel reactor wash-coated with a commercial Cs-promoted Ru/Al2O3 catalyst (ACTA Hypermec 10010). The reactor performance was investigated under atmospheric pressure as a function of reaction temperature (723–873 K) and gas-hourly-space-velocity (65.2–326.1 Nl gcat -1 h-1). Ammonia conversion of 99.8% was demonstrated at 326.1 Nl gcat -1 h-1 and 873 K. The H2 produced at this operating condition was sufficient to yield an estimated fuel cell power output of 60 We and power density of 164 kWe L-1. Overall, the Ru-based microchannel reactor outperformed other NH3 microstructured reformers reported in literature including the Ni-based system used in Chapter 3. Furthermore, the microchannel reactor showed a superior performance against a fixed-bed tubular microreactor with the same Ru-based catalyst. Overall, the high H2 throughput exhibited may promote widespread use of the Ru-based micro-reaction system in high-power applications. Four peer-reviewed journal publications and six conference publications resulted from this work. / PhD (Chemical Engineering), North-West University, Potchefstroom Campus, 2015

The purpose of this study was to explore nurse educators‟ perception of Objective Structured Clinical Evaluation (OSCE) as summative assessment for students‟ clinical competence ,with the aim of recommending alternatives to the current situation. The rationale behind the study is that the researcher became aware of concerns raised by nurse educators regarding the appropriateness of OSCE as summative assessment of students clinical competence and differences of opinion on the matter. An explorative, descriptive, contextual, qualitative research design was chosen. The sample included nurse educators actively involved in OSCE as summative assessment of nursing students in the provincial nursing college for at least 5 years or more. Data was collected by means of two (2) focus group interview sessions with fourteen (14) participants. During data analysis it became clear that data saturation had not been reached and a third focus group interview was conducted with seven (7) participants from the original sample who were available. The focus of the interviews was to explore participants‟ perception of Objective Structured Clinical Evaluation as summative assessment for students‟ clinical competence. The data was independently analyzed by the researcher as well as an independent co-coder according to the principles for content analysis as described by Creswell (2008:251). Three (3) themes and nine (9) sub-themes emerged from the data collected from participants. The first theme described the value of OSCE as summative assessment method for students‟ clinical competence. Theme two described the obstacles in using OSCE as summative assessment for students‟ clinical competence. Theme three described the suggested alternatives. The collected data was discussed and integrated with relevant national and international literature to culminate in three (3) conclusive statements. The conclusive statements served as basis for recommending alternatives to the nursing educators and managers in order to enhance the value of OSCE as summative assessment forstudents‟ clinical competence. / Thesis (MCur)--North-West University, Potchefstroom Campus, 2013

The purpose of this study was to explore nurse educators‟ perception of Objective Structured Clinical Evaluation (OSCE) as summative assessment for students‟ clinical competence ,with the aim of recommending alternatives to the current situation. The rationale behind the study is that the researcher became aware of concerns raised by nurse educators regarding the appropriateness of OSCE as summative assessment of students clinical competence and differences of opinion on the matter. An explorative, descriptive, contextual, qualitative research design was chosen. The sample included nurse educators actively involved in OSCE as summative assessment of nursing students in the provincial nursing college for at least 5 years or more. Data was collected by means of two (2) focus group interview sessions with fourteen (14) participants. During data analysis it became clear that data saturation had not been reached and a third focus group interview was conducted with seven (7) participants from the original sample who were available. The focus of the interviews was to explore participants‟ perception of Objective Structured Clinical Evaluation as summative assessment for students‟ clinical competence. The data was independently analyzed by the researcher as well as an independent co-coder according to the principles for content analysis as described by Creswell (2008:251). Three (3) themes and nine (9) sub-themes emerged from the data collected from participants. The first theme described the value of OSCE as summative assessment method for students‟ clinical competence. Theme two described the obstacles in using OSCE as summative assessment for students‟ clinical competence. Theme three described the suggested alternatives. The collected data was discussed and integrated with relevant national and international literature to culminate in three (3) conclusive statements. The conclusive statements served as basis for recommending alternatives to the nursing educators and managers in order to enhance the value of OSCE as summative assessment forstudents‟ clinical competence. / Thesis (MCur)--North-West University, Potchefstroom Campus, 2013

In this study it is argued that organisations can contribute to development through their Corporate Social Responsibility Initiatives (CSR). Therefore one should consider CSR programmes similar to development programmes and should be managed accordingly. When one communicates in a development context it happens within the extensive field of development communication. In this field the participatory approach to development communication is regarded as the normative approach. In view of this, this study argues that communication in CSR programmes should conform to the principles of the participatory approach. Participatory evaluation is one of the elements of the participatory approach; therefore the evaluation of programmes should adhere to the principles of the participatory approach to contribute to sustainable development. For this reason this study is informed by the relevant principles of the participatory approach to evaluation: dialogue; participation; empowerment and diversity. These principles of participatory evaluation are rooted in the mentioned principles and they are: partnership; participation in evaluation; acknowledgement of local knowledge; empowerment and change. The financial sector in South Africa is one of the largest financial contributors towards CSR. As a result, two financial organisations were chosen to be studied. The research question of this study is: What is the nature of the communication during evaluation of CSR programmes in the financial sector? A qualitative approach is used in this study to obtain the relevant information. Qualitative content analysis, semi-structured interviews and focus groups were used as research methods. The conclusion is made that none of the five programmes in this study use participatory evaluation to evaluate their CSR programmes. In two of the programmes a limited partnership is identified between the organisation and/or the program leader and the beneficiaries, while no partnership was found in the other three programmes. Limited participation from the beneficiaries of the two programmes during evaluation was observed; hence limited local knowledge is recognised in these two programmes. It was also found that only two programmes' beneficiaries are empowered through evaluation and only these two programmes changed according to the beneficiaries’ input. These findings that were made through an empirical study indicate that in spite of the limited presence of some principles of participatory evaluation in two of the five programmes, neither of the organisations uses participatory evaluation methods to evaluate their CSR programmes. / Thesis (MA (Communication Studies))--North-West University, Potchefstroom Campus, 2013