The aims of this research were to investigate, by means of both literature review and empirical research, the incidence and manifestation of conduct disorders among adolescents growing up in the Vaal Triangle townships, with a view to suggesting a psycho-social intervention programme to help them learn life-skills which will decrease their susceptibility to depression and anxiety. According to the literature findings, depression and anxiety co-occur with conduct disorders during adolescence. An intervention progamme can therefore help these learner adolescents develop effective coping skills to help them deal with environmental factors that cause stress, depression and anxiety. The findings from the literature review revealed that adolescence is the highest risk period for the onset of conduct disorders such as, inter alia, substance use disorders, aggressiveness, destruction of property, defiance of authority, frightening and disturbing of adults, fighting, bullying, lying, destructiveness and defiance. The conduct problems also include the more or less troublesome and involuntary behaviours commonly associated with adolescence such as tempertantrums, bouts of screaming and crying, surliness and episodes of commanding or pestering behaviour. The co-occurrence of depression, anxiety and conduct disorders in adolescents was, according to various researchers, also associated with more severe alcohol and drug-related problems, more prolonged depressive and anxiety episodes and increased frequency of behavioural problems, more severe impairment in interpersonal and academic competencies, increased utilization of mental health services, as well as elevated risk of suicide. The literature also revealed that the period of adolescence is also marked by conflicting feelings about security and independence, rapid physical changes, developing sexuality, peer pressure and self-consciousness. This becomes a time of rapid physiological and psychological changes, of intensive re -adjustment to the family, school, work and social life and of preparation for adult roles. These changes are noticeable for their conduct disorders and behavioural accompaniments, and problems arising at this time may attract attention because the adolescent"s conduct and behaviour become obtrusive in the school and the home or elsewhere and evoke a sense of urgency for response. Effective support programmes such as individual educational support and group educational support were regarded by the literature as having the efficacy to prevent the development of conduct disorders. The empirical research findings revealed that adolescent participants who formed the population sample of this research were aggressive; characterized by risky behaviour such as staying with friends until very late at night and coming to school carrying a knife and bullying other children in class; deceitfulness or theft which manifested in the form of stealing from other children's schoolbags, stealing food and pens, and lying; serious violation of rules such as being disruptive in class, bunking school, and not coming to school regularly, conflict with parents, educators and others which manifests in the form of always being in trouble for beating up other learners in class, especially those that are younger, and being rebellious at home, mood disruptions such as bursting in anger, aggressive, being happy one moment and then angry and sad the next, and poor performance at school resulting in failing grades. Recommendations for educational practice and further research were made. / Thesis (M.Ed.)--North-West University, Vaal Triangle Campus, 2006.

The aim of this research were to investigate by means of both the literature review and empirical research, the nature of externalising and internalising of AIDS orphan learners, to investigate the ideas of Ubuntu, Bathe, Vumunhu communitarianism in the context of AIDS orphans suffering as a result of the death of their parents, to investigate the nature what kind of the death of their parents, physical and social problems, to determine which social systems are available in communities to render psychological, physical and social support to AIDS orphan learners, to determine the nature and extent of the educator's knowledge about psychological, physical and social difficulties that AIDS orphan learners experience; and to develop a program with Ubuntu, Bathe and Vumunhu communitarian ideas for supporting AIDS orphan learners in various communities. Findings from the empirical research revealed among others, that orphans in most cases are not aware of the parents' status before they pass away, orphans after they had heard their parents' status, tend to get affected psychologically, socially and emotionally. Orphans are usually not coping with the circumstances they find themselves in, orphans tend to have fear of disclosing causes of death of their relatives, orphans of HIV/AIDS are normally stigmatised and discriminated against by their relatives and members of the community. Orphans usually blame themselves or are blamed by their relatives and community members for being affected and infected with HIV/AIDS. Orphans normally do not have support from their communities, orphans in most cases do not cope financially and materially and they need financial and materialistic support. Most of the orphans do not receive grants from Social Development because they do not have the necessary documentation. Most of the orphans, teachers are usually aware of their situations at homes as well as their parents. Caregivers in most cases are aware of what causes the death of their relatives, caregivers usually know the status of their relatives before they pass away. Caregivers usually do not tell their family members that they are staying with HIV/AIDS orphans, caregivers are normally devoid of family support as well as community and caregivers tend to struggle to survive with financial support. Educators in most cases know the orphans in their classes. Educators usually are aware of the orphan's social problems and orphans usually have a lot of problems that educators do not get help for, because educators have a lot of work to do. Social workers usually have challenges when working with HIV/AIDS orphaned learners. The recommend future research is that it should consist of a larger sample, including participants form different provinces in South Africa. This will help to provide more exact information about the nature and extent of lived experiences of HIV/AIDS orphan learners. There is a need to investigate ways in which educators can be trained by the Department of Education to support learners in the inclusive classroom setting. / Thesis (Ph.D. (Education Management))--North-West University, Vaal Triangle Campus, 2010.

The aims of this research were to investigate, by means of both literature review and empirical research, the incidence and manifestation of conduct disorders among adolescents growing up in the Vaal Triangle townships, with a view to suggesting a psycho-social intervention programme to help them learn life-skills which will decrease their susceptibility to depression and anxiety. According to the literature findings, depression and anxiety co-occur with conduct disorders during adolescence. An intervention progamme can therefore help these learner adolescents develop effective coping skills to help them deal with environmental factors that cause stress, depression and anxiety. The findings from the literature review revealed that adolescence is the highest risk period for the onset of conduct disorders such as, inter alia, substance use disorders, aggressiveness, destruction of property, defiance of authority, frightening and disturbing of adults, fighting, bullying, lying, destructiveness and defiance. The conduct problems also include the more or less troublesome and involuntary behaviours commonly associated with adolescence such as tempertantrums, bouts of screaming and crying, surliness and episodes of commanding or pestering behaviour. The co-occurrence of depression, anxiety and conduct disorders in adolescents was, according to various researchers, also associated with more severe alcohol and drug-related problems, more prolonged depressive and anxiety episodes and increased frequency of behavioural problems, more severe impairment in interpersonal and academic competencies, increased utilization of mental health services, as well as elevated risk of suicide. The literature also revealed that the period of adolescence is also marked by conflicting feelings about security and independence, rapid physical changes, developing sexuality, peer pressure and self-consciousness. This becomes a time of rapid physiological and psychological changes, of intensive re -adjustment to the family, school, work and social life and of preparation for adult roles. These changes are noticeable for their conduct disorders and behavioural accompaniments, and problems arising at this time may attract attention because the adolescent"s conduct and behaviour become obtrusive in the school and the home or elsewhere and evoke a sense of urgency for response. Effective support programmes such as individual educational support and group educational support were regarded by the literature as having the efficacy to prevent the development of conduct disorders. The empirical research findings revealed that adolescent participants who formed the population sample of this research were aggressive; characterized by risky behaviour such as staying with friends until very late at night and coming to school carrying a knife and bullying other children in class; deceitfulness or theft which manifested in the form of stealing from other children's schoolbags, stealing food and pens, and lying; serious violation of rules such as being disruptive in class, bunking school, and not coming to school regularly, conflict with parents, educators and others which manifests in the form of always being in trouble for beating up other learners in class, especially those that are younger, and being rebellious at home, mood disruptions such as bursting in anger, aggressive, being happy one moment and then angry and sad the next, and poor performance at school resulting in failing grades. Recommendations for educational practice and further research were made. / Thesis (M.Ed.)--North-West University, Vaal Triangle Campus, 2006.

The aim of this research were to investigate by means of both the literature review and empirical research, the nature of externalising and internalising of AIDS orphan learners, to investigate the ideas of Ubuntu, Bathe, Vumunhu communitarianism in the context of AIDS orphans suffering as a result of the death of their parents, to investigate the nature what kind of the death of their parents, physical and social problems, to determine which social systems are available in communities to render psychological, physical and social support to AIDS orphan learners, to determine the nature and extent of the educator's knowledge about psychological, physical and social difficulties that AIDS orphan learners experience; and to develop a program with Ubuntu, Bathe and Vumunhu communitarian ideas for supporting AIDS orphan learners in various communities. Findings from the empirical research revealed among others, that orphans in most cases are not aware of the parents' status before they pass away, orphans after they had heard their parents' status, tend to get affected psychologically, socially and emotionally. Orphans are usually not coping with the circumstances they find themselves in, orphans tend to have fear of disclosing causes of death of their relatives, orphans of HIV/AIDS are normally stigmatised and discriminated against by their relatives and members of the community. Orphans usually blame themselves or are blamed by their relatives and community members for being affected and infected with HIV/AIDS. Orphans normally do not have support from their communities, orphans in most cases do not cope financially and materially and they need financial and materialistic support. Most of the orphans do not receive grants from Social Development because they do not have the necessary documentation. Most of the orphans, teachers are usually aware of their situations at homes as well as their parents. Caregivers in most cases are aware of what causes the death of their relatives, caregivers usually know the status of their relatives before they pass away. Caregivers usually do not tell their family members that they are staying with HIV/AIDS orphans, caregivers are normally devoid of family support as well as community and caregivers tend to struggle to survive with financial support. Educators in most cases know the orphans in their classes. Educators usually are aware of the orphan's social problems and orphans usually have a lot of problems that educators do not get help for, because educators have a lot of work to do. Social workers usually have challenges when working with HIV/AIDS orphaned learners. The recommend future research is that it should consist of a larger sample, including participants form different provinces in South Africa. This will help to provide more exact information about the nature and extent of lived experiences of HIV/AIDS orphan learners. There is a need to investigate ways in which educators can be trained by the Department of Education to support learners in the inclusive classroom setting. / Thesis (Ph.D. (Education Management))--North-West University, Vaal Triangle Campus, 2010.

Darbo tyrimų objektas yra duomenų tyrybos empiriniai Bajeso metodai ir algoritmai, taikomi didelio matavimų skaičiaus didelių populiacijų duomenų analizei. Darbo tyrimų tikslas yra sudaryti metodus ir algoritmus didelių populiacijų neparametrinių hipotezių tikrinimui ir duomenų modelių parametrų vertinimui. Šiam tikslui pasiekti yra sprendžiami tokie uždaviniai: 1. Sudaryti didelio matavimo duomenų skaidymo algoritmą. 2. Pritaikyti didelio matavimo duomenų skaidymo algoritmą neparametrinėms hipotezėms tikrinti. 3. Pritaikyti empirinį Bajeso metodą daugiamačių duomenų komponenčių nepriklausomumo hipotezei tikrinti su skirtingais matematiniais modeliais, nustatant optimalų modelį ir atitinkamą empirinį Bajeso įvertinį. 4. Sudaryti didelių populiacijų retų įvykių dažnių vertinimo algoritmą panaudojant empirinį Bajeso metodą palyginant Puasono-gama ir Puasono-Gauso matematinius modelius. 5. Sudaryti retų įvykių logistinės regresijos algoritmą panaudojant empirinį Bajeso metodą. Darbo metu gauti nauji rezultatai įgalina atlikti didelio matavimo duomenų skaidymą; atlikti didelio matavimo nekoreliuotų duomenų pasirinktų komponenčių nepriklausomumo tikrinimą; parinkti didelių populiacijų retų įvykių optimalų modelį ir atitinkamą empirinį Bajeso įvertinį. Pateikta nesinguliarumo sąlyga Puasono-gama modelio atveju. / The research object is data mining empirical Bayes methods and algorithms applied in the analysis of large populations of large dimensions. The aim and objectives of the research are to create methods and algorithms for testing nonparametric hypotheses for large populations and for estimating the parameters of data models. The following problems are solved to reach these objectives: 1. To create an efficient data partitioning algorithm of large dimensional data. 2. To apply the data partitioning algorithm of large dimensional data in testing nonparametric hypotheses. 3. To apply the empirical Bayes method in testing the independence of components of large dimensional data vectors. 4. To develop an algorithm for estimating probabilities of rare events in large populations, using the empirical Bayes method and comparing Poisson-gamma and Poisson-Gaussian mathematical models, by selecting an optimal model and a respective empirical Bayes estimator. 5. To create an algorithm for logistic regression of rare events using the empirical Bayes method. The results obtained enables us to perform very fast and efficient partitioning of large dimensional data; testing the independence of selected components of large dimensional data; selecting the optimal model in the estimation of probabilities of rare events, using the Poisson-gamma and Poisson-Gaussian mathematical models and empirical Bayes estimators. The nonsingularity condition in the case of the Poisson-gamma model is presented.

The research object is data mining empirical Bayes methods and algorithms applied in the analysis of large populations of large dimensions. The aim and objectives of the research are to create methods and algorithms for testing nonparametric hypotheses for large populations and for estimating the parameters of data models. The following problems are solved to reach these objectives: 1. To create an efficient data partitioning algorithm of large dimensional data. 2. To apply the data partitioning algorithm of large dimensional data in testing nonparametric hypotheses. 3. To apply the empirical Bayes method in testing the independence of components of large dimensional data vectors. 4. To develop an algorithm for estimating probabilities of rare events in large populations, using the empirical Bayes method and comparing Poisson-gamma and Poisson-Gaussian mathematical models, by selecting an optimal model and a respective empirical Bayes estimator. 5. To create an algorithm for logistic regression of rare events using the empirical Bayes method. The results obtained enables us to perform very fast and efficient partitioning of large dimensional data; testing the independence of selected components of large dimensional data; selecting the optimal model in the estimation of probabilities of rare events, using the Poisson-gamma and Poisson-Gaussian mathematical models and empirical Bayes estimators. The nonsingularity condition in the case of the Poisson-gamma model is presented. / Darbo tyrimų objektas yra duomenų tyrybos empiriniai Bajeso metodai ir algoritmai, taikomi didelio matavimų skaičiaus didelių populiacijų duomenų analizei. Darbo tyrimų tikslas yra sudaryti metodus ir algoritmus didelių populiacijų neparametrinių hipotezių tikrinimui ir duomenų modelių parametrų vertinimui. Šiam tikslui pasiekti yra sprendžiami tokie uždaviniai: 1. Sudaryti didelio matavimo duomenų skaidymo algoritmą. 2. Pritaikyti didelio matavimo duomenų skaidymo algoritmą neparametrinėms hipotezėms tikrinti. 3. Pritaikyti empirinį Bajeso metodą daugiamačių duomenų komponenčių nepriklausomumo hipotezei tikrinti su skirtingais matematiniais modeliais, nustatant optimalų modelį ir atitinkamą empirinį Bajeso įvertinį. 4. Sudaryti didelių populiacijų retų įvykių dažnių vertinimo algoritmą panaudojant empirinį Bajeso metodą palyginant Puasono-gama ir Puasono-Gauso matematinius modelius. 5. Sudaryti retų įvykių logistinės regresijos algoritmą panaudojant empirinį Bajeso metodą. Darbo metu gauti nauji rezultatai įgalina atlikti didelio matavimo duomenų skaidymą; atlikti didelio matavimo nekoreliuotų duomenų pasirinktų komponenčių nepriklausomumo tikrinimą; parinkti didelių populiacijų retų įvykių optimalų modelį ir atitinkamą empirinį Bajeso įvertinį. Pateikta nesinguliarumo sąlyga Puasono-gama modelio atveju.

During services of the Reformed Churches of South Africa (RCSA), certain psalms and Biblical hymns are used frequently, while others are almost never used. The objective of this study is to determine how the Psalter of 2003 can be used optimally. The model of Zerfass is used for the investigation. The final results of the study are presented in the form of a model that can enrich the optimal use of the Psalter 2003 as means of communication in the liturgy of the RCSA. In Chapters 2 and 3, a basic-theoretical investigation is conducted, with reference to perspectives from Scripture and history. The investigation reveals that music and songs had already played an important role in the church of the Old Testament, and that the Psalms had had a significant influence on the liturgy and the faith. In the New Testament, new hymns are found that supplement those from the Old Testament. The form in which these hymns were composed, was closely connected to the context whence these songs arose. The communication that a hymn effects, is achieved jointly by word and music, in the church of the New Testament and subsequently. Since the Reformation, a degree of separation arose between the songs used in the church and outside, but mutual influences are observed. In Chapters 4 and 5, attention is paid to metatheoretical perspectives, first in communication science, then in hymnology. It is in their singing that the congregation participates in the worship of a church service. Such singing is indeed the basic form of participation, which promotes communication among members of the congregation. In judging a metrical version of a Psalm, attention should especially be paid to the content, style of the text and the melody. In the empirical investigation, qualitative and quantitative methods are used. The investigation proceeds in three phases. In the first phase, information is obtained about the hymns that were sung in a number of congregations in the course of a year. In the second phase, a questionnaire was set and sent to ministers, organists and members of congregations. In the final phase, interviews were conducted with ministers and organists from five congregations. The data show that the hymn occupies an important place in the liturgy. However, the investigation reveals that this point of departure is not fully realised in practice, and some shortcomings are identified. In particular, there is a need for extension of the hymnody, especially by hymns from the New Testament. In Chapter 7, an indication is given of the factors that constrain the optimal use of the Psalter 2003 as means of worship in the church service. The most important problems are: • the incomplete utilisation of the full collection of hymns in the Psalter, • the underuse of the 2001 metrical version, • the repeated use of a small subset of hymns, • problems with the melodies and liturgical usefulness, • limitations in the training of ministers and organists, • resistance to the 2001 metrical version, • a lack of proper programmes to practice the new hymns, and • inadequate support and encouragement by church councils in respect of improving the skills of organists. In view of these problems, a model is proposed, which identifies the relationships among the role players / elements necessary to promote worshipping through singing: • the users of the Psalter 2001, viz. Ministers, organists and members of the congregations, together with the role of the church council, • the Psalter 2003 as hymn book, and • the possible extension of the current corpus of hymns. / Thesis (Ph.D. (Liturgics))--North-West University, Potchefstroom Campus, 2009.

Students enrolled for the Network Systems III module at the Vaal University of Technology are experiencing problems with passing this module. Many of them fail due to the fact that they do not understand the subnet masking part of it. In an attempt to increase the students' pass rate, this study will make additional study material available to them, complying with their learning style preferences. This material will be available as elearning material on the Internet. The usage and success of elearning material implies a holistic approach towards learning styles. Learning styles consist of different interrelated learning elements. This study will make use of an action research approach comprising four phases. In the first phase, different learning styles are diagnosed by means of a literature study. The information obtained is applied to compile an interpretive questionnaire for completion by students. This questionnaire will enable the researcher to do an empirical study with regard to their learning preferences. The data obtained from the questionnaires will be analysed and information obtained will be applied to make additional module related elearning material available on the Internet. During the second phase, results obtained from the empirical investigation will be used to develop elearning material on subnetting, while also addressing the identified learning styles of participants. The elearning material is provided on the Moodle learning management system, enabling students to use it according to their own preferences. In the third phase, the success of the intervention on the elearning material is investigated. In this phase, the activities of students using the elearning material are analysed and tests and examination results processed to determine whether there is any correlation between time spent on elearning material and these results. The usage of elearning material is tested by means of an interpretive questionnaire to the students. The last part of the action research approach deals with the question of whether the research was conducted successfully. A second iteration of the process proved the results to be satisfactory. The elearning material was positively received by students participating in the research, while a growing interest in this material was noticed from the last semester in 2007 to the first semester in 2008. / Thesis (M.Sc. (Computer Science))--North-West University, Potchefstroom Campus, 2011.

A statistical downscaling approach based on multiple linear-regression is used to investigate the predictability of land surface winds over the Canadian prairies and Ontario. This study's model downscales mid-tropospheric predictors (wind components and speed, temperature, and geopotential height) from reanalysis products to predict historical wind observations at thirty-one airport-based weather surface stations in Canada. The model's performance is assessed as a function of: season; geographic location; averaging timescale of the wind statistics; and wind regime, as defined by how variable the vector wind is relative to its mean amplitude. Despite large differences in predictability characteristics between sites, several systematic results are observed. Consistent with recent studies, a strong anisotropy of predictability for vector quantities is observed, while some components are generally well predicted, others have no predictability. The predictability of mean quantities is greater on shorter averaging timescales. In general, the predictability of the surface wind speeds over the Canadian prairies and Ontario is poor; as is the predictability of sub-averaging timescale variability. These results and the relative predictability of vector and scalar wind quantities are interpreted with theoretically- and empirically-derived wind speed sensitivities to the resolved and unresolved variability in the vector winds. At most sites, and on longer averaging timescales, the scalar wind quantities are found to be highly sensitive to unresolved variability in the vector winds. These results demonstrate limitations to the statistical downscaling of wind speed and suggest that deterministic models which resolve the short-timescale variability may be necessary for successful predictions. / Graduate

Nanometer-scale silicon shows extraordinary electronic and optical properties that are not available for bulk silicon, and many investigations toward applications in optoelectronic devices are being pursued. Silicon nanoparticle films made from solution are a promising candidate for low-cost solar cells. However, controlling the properties of silicon nanoparticles is quite a challenge, in particular shape and size distribution, which effect device performance. At present, none of the solar cells made from silicon nanoparticle films have an efficiency exceeding the efficiency of those based on crystalline silicon. To address the challenge of controlling silicon nanoparticle properties, both theoretical and experimental investigations are needed. In this thesis, we investigate silicon nanoparticle properties via quantum mechanical modeling of silicon nanoparticles and synthesis of silicon nanoparticle films via colloidal grinding. Silicon nanoparticles with shapes including cubic, rectangular, ellipsoidal and flat disk are modeled using semi-empirical methods and configuration interaction. Their electronic properties with different surface passivation were also studied. The results showed that silicon nanoparticles with hydrogen passivation have higher HOMOLUMO gaps, and also the HOMO-LUMO gap depends on the size and the shape of the particle. In contrast, silicon nanoparticles with oxygen passivation have a lower HOMO-LUMO gap. Raman spectroscopy calculation of silicon nanoparticles show peak shift and asymmetric broadening similar to what has been observed in experiment. Silicon nanoparticle synthesis via colloidal grinding was demonstrated as a straightforward and inexpensive approach for thin film solar cells. Data analysis of silicon particles via SEM images demonstrated that colloidal grinding is effective in reducing the Si particle size to sub-micron in a short grinding time. Further increases in grinding time, followed by filtration demonstrated a narrowing of the Si particle size and size-distribution to an average size of 70 nm. Raman spectroscopy and EDS data demonstrated that the Si nanoparticles contain oxygen due to exposure to air during grinding. I-V characterization of the milled Si nanoparticles showed an ohmic behaviour with low current at low biases then Schottky diode behaviour or a symmetric curve at large biases. / Graduate / 0794 / 0544 / zahraalbu@hotmail.com