Thesis (Doctoral)--Universiteit van Amsterdam, 1982.

Progischrift--Amsterdam. / Bibliographical foot-notes.

This research project examines the acculturation process in order to predict the perceived work success and health (psychological and physical) of mineworkers in a mine in the North–West Province.1 Work success can also be described as that which is achieved when an employee enjoys his career for reasons of psychological experience of success and personal growth and development within both his/her current occupation and working environment. Health is defined as a condition of complete physical, mental and social well–being and not merely the absence of disease or frailty. Health is therefore about completeness, contentment and well–being at a physical, cultural, psychosocial, economic and spiritual level. Employees’ success and health is evaluated from an acculturation perspective, and therefore considered a result of the acculturation process. This proposition was explored by investigating the relationship between the acculturation context and individual intervening factors, mapped into variables, and acculturation outcomes (work success and health). A convenient sample of participants from the mine examined was taken (n = 288). English questionnaires using a cross–sectional survey design were used to gather the data. Modified measuring instruments and others developed for the project, which follow a five–point Likert format (‘strongly agree’ to ‘strongly disagree’) were used to investigate the mainstream domain (perceived mainstream segregation demands, perceived pressure to conform to management ideologies and practices, perceived racism at work, perceived discrimination at work, and relationships with mainstream members at work), an individual intervening factor (individual separation acculturation strategy practices), the ethnocultural domain (perceived pressure to conform to own culture, ethnic separation demands at work, and relationships with co–ethnics at work), psychological acculturation outcomes (health), and sociocultural acculturation outcomes (work success). The data was captured in a spreadsheet, controlled for errors, and statistically analysed using regression in SPSS. Descriptive statistics, Cronbach alpha coefficients, and Pearson product-moment correlation coefficients were inspected, and effect sizes were used to determine the findings’ practical significance. The results did indicate practical and statistically significant relationships exist between acculturation context, individual and acculturation outcomes variables. Perceived pressure to conform to management ideologies and practices, perceived racism at work, perceived discrimination at work, and relationships with co–ethnics at work proved to be statistically significant predictors of meeting deadlines at work. Perceived pressure to conform to management ideologies and practices, perceived racism at work, perceived discrimination at work, and relationships with co–ethnics at work was statistically significant predictors of reputation and respect at work. Perceived mainstream segregation demands, perceived pressure to conform to management ideologies and practices, perceived racism at work, and relationships with mainstream members at work were statistically significant predictors of training and development opportunities at work. Individual separation acculturation strategy practices and ethnic separation demands at work were statistically significant predictors of psychological health. Perceived racism at work and ethnic separation demands at work proved to be statistically significant predictors of physical health. These findings demonstrate that success and health can be viewed from an acculturation perspective, and that the acculturation context and individual intervening factors, can be used to predict psychological and sociocultural acculturation outcomes. / Thesis (M.A. (Human Resource Management))--North-West University, Potchefstroom Campus, 2010.

This research project examines the acculturation process in order to predict the perceived work success and health (psychological and physical) of mineworkers in a mine in the North–West Province.1 Work success can also be described as that which is achieved when an employee enjoys his career for reasons of psychological experience of success and personal growth and development within both his/her current occupation and working environment. Health is defined as a condition of complete physical, mental and social well–being and not merely the absence of disease or frailty. Health is therefore about completeness, contentment and well–being at a physical, cultural, psychosocial, economic and spiritual level. Employees’ success and health is evaluated from an acculturation perspective, and therefore considered a result of the acculturation process. This proposition was explored by investigating the relationship between the acculturation context and individual intervening factors, mapped into variables, and acculturation outcomes (work success and health). A convenient sample of participants from the mine examined was taken (n = 288). English questionnaires using a cross–sectional survey design were used to gather the data. Modified measuring instruments and others developed for the project, which follow a five–point Likert format (‘strongly agree’ to ‘strongly disagree’) were used to investigate the mainstream domain (perceived mainstream segregation demands, perceived pressure to conform to management ideologies and practices, perceived racism at work, perceived discrimination at work, and relationships with mainstream members at work), an individual intervening factor (individual separation acculturation strategy practices), the ethnocultural domain (perceived pressure to conform to own culture, ethnic separation demands at work, and relationships with co–ethnics at work), psychological acculturation outcomes (health), and sociocultural acculturation outcomes (work success). The data was captured in a spreadsheet, controlled for errors, and statistically analysed using regression in SPSS. Descriptive statistics, Cronbach alpha coefficients, and Pearson product-moment correlation coefficients were inspected, and effect sizes were used to determine the findings’ practical significance. The results did indicate practical and statistically significant relationships exist between acculturation context, individual and acculturation outcomes variables. Perceived pressure to conform to management ideologies and practices, perceived racism at work, perceived discrimination at work, and relationships with co–ethnics at work proved to be statistically significant predictors of meeting deadlines at work. Perceived pressure to conform to management ideologies and practices, perceived racism at work, perceived discrimination at work, and relationships with co–ethnics at work was statistically significant predictors of reputation and respect at work. Perceived mainstream segregation demands, perceived pressure to conform to management ideologies and practices, perceived racism at work, and relationships with mainstream members at work were statistically significant predictors of training and development opportunities at work. Individual separation acculturation strategy practices and ethnic separation demands at work were statistically significant predictors of psychological health. Perceived racism at work and ethnic separation demands at work proved to be statistically significant predictors of physical health. These findings demonstrate that success and health can be viewed from an acculturation perspective, and that the acculturation context and individual intervening factors, can be used to predict psychological and sociocultural acculturation outcomes. / Thesis (M.A. (Human Resource Management))--North-West University, Potchefstroom Campus, 2010.

In many occupations, exposure to hand-transmitted vibration (HTV) over a prolonged period causes various disorders involving the vascular, neural and musculoskeletal systems, collectively known as the hand-arm vibration syndrome (HAVS). It is a complex and potentially disabling chronic disorder of the upper extremities, especially of the hands. Numbness, tingling, reduced tactile discrimination, and impaired manipulative dexterity are often reported by workers exposed to HTV. The precise pathophysiological mechanism responsible for vascular injuries in HAVS has not yet been fully clarified; it seems to be multifactorial and highly complex. Interaction of neural signals, hormones, mediators and changes in the blood vessel itself appear to contribute to the development of such vascular injuries. This study aims to assess the risk of the hand-transmitted vibration exposure during pneumatic impact wrench operation in a rock drill repair and maintenance workshop at a South African platinum mine. A total of 8 workers working on a day to day basis with impact wrenches were available for this study. For each of the workers a control (not exposed to vibration) was selected on the basis of gender, ethnic group, smoking habits, age and body mass index (BMI). Grip force, dexterity and hand-eye co-ordination were tested on the workers and control group before and after work. Finger systolic blood pressure (FSBP) was also measured after cold provocation of the worker and control groups. Results have shown astatistically significant difference between the two groups with respect coordination, dexterity and FSBP after cold provocation. Vibration measurements shows three workers had values above the suggested ELV of 5 m/s² for an eight hour A (8) workday. With regards to dexterity, workers were capable to manipulate small objects better with their dominant right (vibration exposed) hand after work than before work. In contrast, it seems that the number of pegs correctly inserted by the controls is not uniformly affected by their 8 hour workday. The worker group showed a greater grip force than that of the control group, both before and after work.There was a statistically significant difference between the control and worker group with respect to the number of mistakes during the mirror trace and the time to complete this test only for the right hand. The difference in FSBP after cold provocation between the control and worker group observed is of medium importance when compared with effect sizes, however, there was no statistical significant difference. In this study, it was very difficult to make valid conclusions due to the limitations of a small sample size. A longitudinal study should be conducted preferably using newly appointed workers with no prior exposure to vibration and a sufficient control group to eliminate the effect other confounding variables such as general working conditions. / Thesis (MSc (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2013.

In many occupations, exposure to hand-transmitted vibration (HTV) over a prolonged period causes various disorders involving the vascular, neural and musculoskeletal systems, collectively known as the hand-arm vibration syndrome (HAVS). It is a complex and potentially disabling chronic disorder of the upper extremities, especially of the hands. Numbness, tingling, reduced tactile discrimination, and impaired manipulative dexterity are often reported by workers exposed to HTV. The precise pathophysiological mechanism responsible for vascular injuries in HAVS has not yet been fully clarified; it seems to be multifactorial and highly complex. Interaction of neural signals, hormones, mediators and changes in the blood vessel itself appear to contribute to the development of such vascular injuries. This study aims to assess the risk of the hand-transmitted vibration exposure during pneumatic impact wrench operation in a rock drill repair and maintenance workshop at a South African platinum mine. A total of 8 workers working on a day to day basis with impact wrenches were available for this study. For each of the workers a control (not exposed to vibration) was selected on the basis of gender, ethnic group, smoking habits, age and body mass index (BMI). Grip force, dexterity and hand-eye co-ordination were tested on the workers and control group before and after work. Finger systolic blood pressure (FSBP) was also measured after cold provocation of the worker and control groups. Results have shown astatistically significant difference between the two groups with respect coordination, dexterity and FSBP after cold provocation. Vibration measurements shows three workers had values above the suggested ELV of 5 m/s² for an eight hour A (8) workday. With regards to dexterity, workers were capable to manipulate small objects better with their dominant right (vibration exposed) hand after work than before work. In contrast, it seems that the number of pegs correctly inserted by the controls is not uniformly affected by their 8 hour workday. The worker group showed a greater grip force than that of the control group, both before and after work.There was a statistically significant difference between the control and worker group with respect to the number of mistakes during the mirror trace and the time to complete this test only for the right hand. The difference in FSBP after cold provocation between the control and worker group observed is of medium importance when compared with effect sizes, however, there was no statistical significant difference. In this study, it was very difficult to make valid conclusions due to the limitations of a small sample size. A longitudinal study should be conducted preferably using newly appointed workers with no prior exposure to vibration and a sufficient control group to eliminate the effect other confounding variables such as general working conditions. / Thesis (MSc (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2013.

Hydrogen production via the electrolysis of water has gained a lot of attention in the last couple of years. Research related to electrolysers is mostly aimed towards decreasing the noble–metal catalyst content. In this study the presently used catalyst application techniques were reviewed and critically examined to find commercially applicable and effective methods. Selected methods were then practically applied to determine their feasibility and to gain “know–how” related to the practical application of these techniques. The selected techniques were the hand paint, inkjet print, screen print and spray paint techniques. Meaningful comparisons were made between the methods in terms of parameters such as practicality, waste of catalyst and microstructure. The results point out that the hand paint and spray paint methods are feasible methods although there are improvements to be made. The hand paint method was improved by applying a carbon micro porous layer to the gas diffusion layer before the painting is carried out. The addition of the carbon layer reduced the soaking of the catalyst–containing ink through the gas diffusion layer. A method not initially investigated was identified an evaluated and showed promising results in lowering the mass of catalyst applied. This method comprised of sputtering a layer of catalyst material onto a prepared gas diffusion layer. It also came to light from the results that electrodes, and therefore membrane electrode assemblies, can be produced at a much lower cost than the commercial available membrane electrode assemblies. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2012.

Hydrogen production via the electrolysis of water has gained a lot of attention in the last couple of years. Research related to electrolysers is mostly aimed towards decreasing the noble–metal catalyst content. In this study the presently used catalyst application techniques were reviewed and critically examined to find commercially applicable and effective methods. Selected methods were then practically applied to determine their feasibility and to gain “know–how” related to the practical application of these techniques. The selected techniques were the hand paint, inkjet print, screen print and spray paint techniques. Meaningful comparisons were made between the methods in terms of parameters such as practicality, waste of catalyst and microstructure. The results point out that the hand paint and spray paint methods are feasible methods although there are improvements to be made. The hand paint method was improved by applying a carbon micro porous layer to the gas diffusion layer before the painting is carried out. The addition of the carbon layer reduced the soaking of the catalyst–containing ink through the gas diffusion layer. A method not initially investigated was identified an evaluated and showed promising results in lowering the mass of catalyst applied. This method comprised of sputtering a layer of catalyst material onto a prepared gas diffusion layer. It also came to light from the results that electrodes, and therefore membrane electrode assemblies, can be produced at a much lower cost than the commercial available membrane electrode assemblies. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2012.

Emotional home demands, cognitive home demands, home pressure, development possibilities, autonomy, social support, nonwork–work interference, spouse–work interference, parent–work interference, religion/spiritual–work interference, domestic–work interference, health, exhaustion, cognitive weariness, life satisfaction, dual earner parents Dual earner parents have become the norm in today’s workplace (Weigel, Weigel, Berger, Cook, & Delcampo, 1995). Dual earner parents face many challenging roles that they have to try to balance; these include being a parent, spouse, employee, being involved in religious practices and juggling domestic responsibilities. According to Duxbury and Higgins (1991), it is very difficult for such parents to balance their various roles and multiple demands. All these challenging demands (home characteristics) can cause nonwork–interference which can, in turn, lead to well–being problems (Magnus & Viswesvaran, 2005). The general objective of this study is to investigate the home characteristics, nonwork–work interference and well–being of a sample of dual earner parents. A convenience sample of dual earner parents (N=207) was taken in the Vaal Triangle area in Gauteng. The following scales was used within this study: the Home Demands Scale (Peeters et al., 2005), Home Resources Scale (Demerouti et al., 2010); the Work–nonwork Interference Scale (Koekemoer, Mostert, & Rothmann, 2010); the General Health Questionnaire (GHQ) (Goldberg, & Williams, 1988); and the OLBI (Oldenburg Burnout Inventory) Scale measuring exhaustion, Cognitive weariness (Van Horn et al., 2004); and life satisfaction (Diener et al., 1985). Descriptive statistics, Cronbach alpha coefficients, product moment correlations and multiple regression analyses were used to analyse the data. The results indicated that emotional home demands and lack of autonomy significantly predict physical ill health; emotional home demands and spouse–work interference significantly predict anxiety; and emotional home demands significantly predict depression. Gender, home pressure, developmental possibilities and parent–work interference were, in turn, significant predictors of exhaustion. Recommendations were made for future research and also, on a more practical level, for dual earner parents. One of the recommendations is that one needs to investigate the possible cross–over and spillover effects of work–nonwork interference between wives and husbands. Another is to investigate the positive side of work–nonwork interference. / Thesis (M.Com. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2012.

Emotional home demands, cognitive home demands, home pressure, development possibilities, autonomy, social support, nonwork–work interference, spouse–work interference, parent–work interference, religion/spiritual–work interference, domestic–work interference, health, exhaustion, cognitive weariness, life satisfaction, dual earner parents Dual earner parents have become the norm in today’s workplace (Weigel, Weigel, Berger, Cook, & Delcampo, 1995). Dual earner parents face many challenging roles that they have to try to balance; these include being a parent, spouse, employee, being involved in religious practices and juggling domestic responsibilities. According to Duxbury and Higgins (1991), it is very difficult for such parents to balance their various roles and multiple demands. All these challenging demands (home characteristics) can cause nonwork–interference which can, in turn, lead to well–being problems (Magnus & Viswesvaran, 2005). The general objective of this study is to investigate the home characteristics, nonwork–work interference and well–being of a sample of dual earner parents. A convenience sample of dual earner parents (N=207) was taken in the Vaal Triangle area in Gauteng. The following scales was used within this study: the Home Demands Scale (Peeters et al., 2005), Home Resources Scale (Demerouti et al., 2010); the Work–nonwork Interference Scale (Koekemoer, Mostert, & Rothmann, 2010); the General Health Questionnaire (GHQ) (Goldberg, & Williams, 1988); and the OLBI (Oldenburg Burnout Inventory) Scale measuring exhaustion, Cognitive weariness (Van Horn et al., 2004); and life satisfaction (Diener et al., 1985). Descriptive statistics, Cronbach alpha coefficients, product moment correlations and multiple regression analyses were used to analyse the data. The results indicated that emotional home demands and lack of autonomy significantly predict physical ill health; emotional home demands and spouse–work interference significantly predict anxiety; and emotional home demands significantly predict depression. Gender, home pressure, developmental possibilities and parent–work interference were, in turn, significant predictors of exhaustion. Recommendations were made for future research and also, on a more practical level, for dual earner parents. One of the recommendations is that one needs to investigate the possible cross–over and spillover effects of work–nonwork interference between wives and husbands. Another is to investigate the positive side of work–nonwork interference. / Thesis (M.Com. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2012.