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Incomplete data represents a major challenge for a successful prediction and subsequent removal of multiples. In this paper, a new method will be represented that tackles this challenge in a two-step approach. During the first step, the recenly developed curvelet-based recovery by sparsity-promoting inversion (CRSI) is applied to the data, followed by a prediction of the primaries. During the second high-resolution step, the estimated primaries are used to improve the frequency content of the recovered data by combining the focal transform, defined in terms of the estimated primaries, with the curvelet transform. This focused curvelet transform leads to an improved recovery, which can subsequently be used as input for a second stage of multiple prediction and primary-multiple separation.

n this paper, two different applications of phase transitions to exploration seismology will be discussed. The first application concerns a phase diagram ruling the recovery conditions for seismic data volumes from incomplete and noisy data while the second phase transition describes the behavior of bi-compositional mixtures as a function of the volume fraction. In both cases, the phase transitions are the result of randomness in large system of equations in combination with nonlinearity. The seismic recovery problem from incomplete data involves the inversion of a rectangular matrix. Recent results from the field of "compressive sensing" provide the conditions for a successful recovery of functions that are sparse in some basis (wavelet) or frame (curvelet) representation, by means of a sparsity ($\ell_1$-norm) promoting nonlinear program. The conditions for a successful recovery depend on a certain randomness of the matrix and on two parameters that express the matrix' aspect ratio and the ratio of the number of nonzero entries in the coefficient vector for the sparse signal representation over the number of measurements. It appears that the ensemble average for the success rate for the recovery of the sparse transformed data vector by a nonlinear sparsity promoting program, can be described by a phase transition, demarcating the regions for the two ratios for which recovery of the sparse entries is likely to be successful or likely to fail. Consistent with other phase transition phenomena, the larger the system the sharper the transition. The randomness in this example is related to the construction of the matrix, which for the recovery of spike trains corresponds to the randomly restricted Fourier matrix. It is shown, that these ideas can be extended to the curvelet recovery by sparsity-promoting inversion (CRSI) . The second application of phase transitions in exploration seismology concerns the upscaling problem. To counter the intrinsic smoothing of singularities by conventional equivalent medium upscaling theory, a percolation-based nonlinear switch model is proposed. In this model, the transport properties of bi-compositional mixture models for rocks undergo a sudden change in the macroscopic transport properties as soon as the volume fraction of the stronger material reaches a critical point. At this critical point, the stronger material forms a connected cluster, which leads to the creation of a cusp-like singularity in the elastic moduli, which in turn give rise to specular reflections. In this model, the reflectivity is no longer explicitly due to singularities in the rocks composition. Instead, singularities are created whenever the volume fraction exceeds the critical point. We will show that this concept can be used for a singularity-preserved lithological upscaling.

Soybean (Glycine max (L.) Merr.) is a subtropical legume that requires root zone temperatures (RZTs) in the 25 to 30$ sp circ$C range for optimal symbiotic activity. The inability of soybean to adapt to cool soil conditions limits its development and yield in short season areas. In particular, nodulation and N$ sb2$ fixation by this subtropical crop species is sensitive to cool (RZT). The objectives of this thesis were to determine whether or not PGPR could be used to help overcome the low RZT inhibition of soybean nodulation, to improve soybean nitrogen fixation and yield under field conditions and to determine the methods by which such increases occurred. The work reported in this thesis has demonstrated that PGPR can increase early season nodulation and total seasonal nitrogen fixation and yield of soybean growing in an area with cool spring soils. The ability of PGPR to stimulate soybean nodulation and growth was shown to be related to their ability to colonize soybean roots, and this was shown to be related to RZT. All steps in early nodulation were stimulated by the presence of PGPR. The beneficial effects of PGPR are exerted through a diffusible molecule excreted into the growth medium. The addition of genistein, a plant-to-bacteria signal molecule already shown to stimulate soybean N$ sb2$ fixation at low RZT, plus PGPR causes increases in soybean nodulation, N$ sb2$ fixation, and growth that were greater than those caused by the addition of PGPR alone, but only at 25 and 17.5$ sp circ$C, and not at 15$ sp circ$C RZT.

Globally there is a serious need to equip children and young people with knowledge, attitudes, skills and values to assist them in making healthy lifestyle choices. Life skills education is possibly among the most important answers to the problems and challenges many young people are faced with. Life skills programs are being developed to address the alarming increase in high risk health behaviours among adolescents. According to international research, Health promotion is a critical life skill to acquire, since health impacts on almost every facet of a person and their society. The South African Department of Education introduced Life Orientation as a Learning Area as part of Outcomes Based Education. The paramount role of Life Orientation within the context of the Health Promoting School is increasingly being recognised by educational planners, policy makers, school managers, teachers, parents and even learners themselves. Health promotion as part of Life Orientation aspires to promote a healthy lifestyle and equip learners with the knowledge and skills to attain and maintain a healthy lifestyle. It further aims to reduce risk behaviours and equip learners with social skills. Empirical research was done in the Gauteng Province of South Africa. In order to give voice to teachers and health co-ordinators in terms of their views and comments on Life Orientation, questionnaires and focus group interviews were utilised. Based on the evidence gathered in questionnaires, discussions and observations in the selected Health Promoting Schools, it emerged that Life Orientation has a major role to play in instilling knowledge and skills to promote health and well-being. However, even though Health promotion is included in the Life Orientation curriculum, there seems to be a lack of energy and motivation to progress to Health Promoting Schools. It emerged that Life Orientation teachers viewed a healthy lifestyle as the link between Life Orientation and Health promotion, which is a positive indication that schools are making progress towards becoming Health Promoting Schools. Furthermore, the quantitative research revealed key issues that need be dealt with, especially proper water and sanitation, policies on tobacco and substance use, the enhancement of physical well-being of the learners and an integrated nutrition program. Schools need an effective safety and security plan to ensure a safe school environment conducive to teaching-and-learning. Learners should receive basic health screening with appropriate referrals from school nurses. Also, trained health promoters should oversee and manage the health promoting program in the Health Promoting School. The qualitative research indicated that healthy lifestyles are promoted, with particular focus on balanced diets, clean and hygienic environments and adequate physical activity. It emerged that stakeholders play an important role, including the community, school nurses, private companies and governmental departments. Community involvement is particularly important, since community members assist the school by cleaning, cooking, gardening and participating in health promoting awareness. It can be concluded that Life Orientation has a prominent role to play in the Health Promoting School. A successful initiative requires the involvement of the entire school, changes to the schools’ psychosocial environment and participation from the parents and wider community. / Thesis (PhD (Educational Psychology))--North-West University, Potchefstroom Campus, 2013.

The introduction of training and skills development legislation, such as the Skills Development Act No. 97 of 1998, and the Skills Development Levies Act No. 9 of 1999, has forced organisations to invest in the development of skills of its employees in South Africa. The National Skills Development Strategy, the Human Resource Development Strategy for South Africa and the Accelerated and Shared Growth Initiative for South Africa (ASGISA) are other legislative measures introduced by the South African government to contribute to the importance of training and skills development in organisations. It is necessary for the public sector organisations to train and develop the skills of its personnel in order to improve organisational, team and individual performance. Training and skills development should also assist in forming the basis for lifelong learning and to increase productivity and quality of work. A comprehensive human resource training and development strategy should be linked to the business strategy and the human resource management strategy in organisations. The primary objective of this study was to analyse the views of employees and to determine their level of awareness regarding training and skills development and how these can improve performance in the Free State Province municipalities. To reach this primary objective, a number of secondary objectives were considered as relevant. These included exploring the concepts of training, skills development and performance management. An analysis of statutory and regulatory guidelines pertaining to training and skills development and the assessment of structures, procedures and processes that exist in municipalities for the promotion of training and skills development were also highlighted. The effects of adequate training and skills development on performance in the Free State Province municipalities were analysed. Lastly, guidelines and recommendations regarding training, skills development and performance management were developed for municipalities in the Free State Province. The research was conducted in the Free State Province municipalities. It comprised of a literature study and an empirical survey using questionnaires and interviews to obtain information from managers, supervisors and frontline staff in the Free State Province municipalities. The respondents were tested on their views regarding the impact of training and skills development programmes in improving performance in their workplace. The findings of this research demonstrated that training and skills development enhances performance of personnel in specific functional areas in the Free State Province municipalities, and for this to be more effective on performance in municipalities, it should be provided adequately in specific areas of the Local Government Five Year Strategic Agenda, particularly to the Free State Province municipalities. Some of the most important findings of this research are the following: •that most of the managers and frontline staff in Free State Province municipalities received adequate training and skills development programmes; •that most of the trainings and skills development programmes received by managers in the Free State Province municipalities were related to their job tasks; •that managers and frontline staff in Free State Province municipalities felt motivated to do their job tasks after they were provided with training and skills development programmes; •that managers in Free State Province municipalities still find it difficult to ensure public participation by their communities even after training and skills development programmes were provided to them; and •that adequate training and skills development of personnel improves performance in many functional areas in municipalities in Free State Province. The study ends with recommendations for management actions on training needs, and for further research on this topic. / PhD (Public Management and Governance), North-West University, Vaal Triangle Campus, 2013

The quality of education in especially the Further Education and Training phase (FET) is recognised as one of the most significant challenges facing the South African government. Low teacher morale, lack of parental involvement, learners' ignorance in taking responsibility for their own learning and other educational problems are all identified as contributing factors. This study was undertaken to investigate how critical thinking skills can contribute to promoting quality teaching and learning in secondary schools with specific reference to the FET phase. The study also sought to make recommendations that will assist teachers to integrate critical thinking skills into the teaching and learning experiences in the FET phase. The nature of quality teaching and learning, the nature of critical thinking skills and the correlation between the concepts to improve the quality of education were researched by means of a literature study. A quantitative research design followed, using questionnaires as research instrument. From the research conducted it was found that learners in the FET phase do not take responsibility for their learning and therefore many of these learners still do not perceive learning as important. However, effective learning could take place if learners are confident, independent, active participants and explore a variety of learning strategies. Teachers, on the other hand, should adopt particular forms of behaviour to foster certain types of learning. The ability to teach critical thinking skills to learners poses a great challenge as many teachers are not trained to do so. This has a great influence on the exposure of an integrated constructivist method of teaching and learning and therefore inflicts on the delivery of quality teaching and learning in the FET phase of secondary schools in South Africa. / MEd, North-West University, Vaal Triangle Campus, 2011

Globally there is a serious need to equip children and young people with knowledge, attitudes, skills and values to assist them in making healthy lifestyle choices. Life skills education is possibly among the most important answers to the problems and challenges many young people are faced with. Life skills programs are being developed to address the alarming increase in high risk health behaviours among adolescents. According to international research, Health promotion is a critical life skill to acquire, since health impacts on almost every facet of a person and their society. The South African Department of Education introduced Life Orientation as a Learning Area as part of Outcomes Based Education. The paramount role of Life Orientation within the context of the Health Promoting School is increasingly being recognised by educational planners, policy makers, school managers, teachers, parents and even learners themselves. Health promotion as part of Life Orientation aspires to promote a healthy lifestyle and equip learners with the knowledge and skills to attain and maintain a healthy lifestyle. It further aims to reduce risk behaviours and equip learners with social skills. Empirical research was done in the Gauteng Province of South Africa. In order to give voice to teachers and health co-ordinators in terms of their views and comments on Life Orientation, questionnaires and focus group interviews were utilised. Based on the evidence gathered in questionnaires, discussions and observations in the selected Health Promoting Schools, it emerged that Life Orientation has a major role to play in instilling knowledge and skills to promote health and well-being. However, even though Health promotion is included in the Life Orientation curriculum, there seems to be a lack of energy and motivation to progress to Health Promoting Schools. It emerged that Life Orientation teachers viewed a healthy lifestyle as the link between Life Orientation and Health promotion, which is a positive indication that schools are making progress towards becoming Health Promoting Schools. Furthermore, the quantitative research revealed key issues that need be dealt with, especially proper water and sanitation, policies on tobacco and substance use, the enhancement of physical well-being of the learners and an integrated nutrition program. Schools need an effective safety and security plan to ensure a safe school environment conducive to teaching-and-learning. Learners should receive basic health screening with appropriate referrals from school nurses. Also, trained health promoters should oversee and manage the health promoting program in the Health Promoting School. The qualitative research indicated that healthy lifestyles are promoted, with particular focus on balanced diets, clean and hygienic environments and adequate physical activity. It emerged that stakeholders play an important role, including the community, school nurses, private companies and governmental departments. Community involvement is particularly important, since community members assist the school by cleaning, cooking, gardening and participating in health promoting awareness. It can be concluded that Life Orientation has a prominent role to play in the Health Promoting School. A successful initiative requires the involvement of the entire school, changes to the schools’ psychosocial environment and participation from the parents and wider community. / Thesis (PhD (Educational Psychology))--North-West University, Potchefstroom Campus, 2013.

A series of acts which were passed during the apartheid era have undoubtedly deprived the marginalized groups, namely, the so called Coloureds, Indians and the black majority their political rights. Apartheid policies enshrined in the then constitution, ill-considered the wellbeing and wellness of these groups, while at the same time, a white minority was solely privileged. Being the victims of segregation, the deprived groups continuously suffered from the political, and socio-economic setbacks, which disabled them to lead healthy lifestyles. Racial division which was prevalent in many workplaces, particularly in the mining sector, disadvantaged many of them, blacks in particular, to perform skilled labour. They were therefore destined to perform unskilled labour which classified them as cheap labourers, hence meagre wages. The results of segregation bore the fruits of abject poverty which impacted negatively on many. Problems of housing and infrastructure are still confronting many households to date since scores of them are 'shack dwellers' nationwide, living in squalid conditions which are a threat to their health. Overcrowding and poor teaching and learning were prime causes of learners to discontinue their education prematurely. High dropout rates became prevalent mostly in rural areas, where schooling accommodation was limited. Schools can only be safe places of teaching and learning when all horrifying acts of violence such as sexual abuse, rape, intimidation, assaults, bullying and murder are urgently eliminated. All the stakeholders in education should collectively work together to ensure that health promotion in schools is maintained. Against the abovementioned background the primary aim of this research was to determine what health promotion entails within the context of a selected group of 10 primary schools in the Southern Region of the North West Province. A qualitative research methodology was selected to achieve this outcome. Data was gathered by means of focus group interviews. The transcriptions were analysed generating items that were labeled as main categories and subcategories. Pertaining the main categories it was evident that are several aspects that can determine the health and well-being in a school. These include: the leadership of the school, the role of the parents, the duties of the educators, the existence of plans and the policy concerning HIV/Aids. / Thesis (M.Ed.)--North-West University, Potchefstroom Campus, 2007.

The main focus of this study was to explore how personal constructions, consisting of latent and conscious schema, and obtained from a culturally sensitive interpretation of the RCS, informed the transactional resilience of Black South African adolescents. This study was motivated in view of limited knowledge available about the (i) processes that are generic to the resilience-promoting transactions of Black South African adolescents and (ii) to potentiate insight into an adolescent’s construction of personal meaning of her conscious and unconscious experiences that may not always be easily recognised in her overt behaviour or by self-report measures often used in South African resilience research. Six Black South African adolescents aged 14 to 16 years volunteered to take part in this multiple case study. The participants were identified as resilient by an advisory panel consisting of learners and educators at an English-medium school in the Vaal Triangle area. In this essentially qualitative study, qualitative data obtained from an unstructured individual interview, unstructured observations, and a follow-up interview were integrated with the data obtained from a culturally sensitive, conceptual interpretation of these Black adolescents’ Rorschach protocols. The structural, quantitative data obtained from specific indicators in Exner’s Comprehensive System were interpreted in a culturally sensitive manner and integrated with the qualitative data obtained from the Rorschach protocols. A culturally sensitive, conceptual framework for interpreting Rorschach indicators associated with adolescents’ transactional resilience was provided. These findings indicated individual and ecological protective resources well known within South African resilience research. Findings that contributed new understanding of the transactional processes associated with Black South African adolescent resilience were also obtained. Four case-specific self-reflective strategies were identified, namely, emotional stoicism, frequent introspection, honouring the past, and adopting a new identity. These selfreflective strategies served as the participants’ unique ways of compensating for their adversity-informed schema as well as encouraging them to navigate towards the sustained support of specific significant others and resilience-promoting ecological resources. The participants indicated that attachment challenges brought about repressed feelings and specific security needs, which shaped their resilience-promoting navigation and enabled them to self-knit in a resilient way. / Thesis (Ph.D. (Education))--North-West University, Vaal Triangle Campus, 2011